[Objective] This study aimed to compare the detection results of antibodies against infectious bursal disease virus with test strips and agar gel immunodiffusion method. [Method] Antibodies against infectious bursal d...[Objective] This study aimed to compare the detection results of antibodies against infectious bursal disease virus with test strips and agar gel immunodiffusion method. [Method] Antibodies against infectious bursal disease virus in chicken serum were detected using test strips developed in our laboratory, and the results were comparad^with that using traditional agar diffusion method. [Result] The comparative study of the two methods showed that the sensitivity of test strips was eight times over agar gel immunodiffusion; test strips showed higher detection rate in the deter- mination test of 216 clinical samples, with high specificity, easy preservation, and simple and rapid operation, thereby being more suitable for the monitoring of clinical antibodies. [Conclusion] Test strips could replace the existing serological methods, having great promotion and application value in antibody monitoring.展开更多
Surface notches lower the stiffness of laminated strips, so they lower the buckling loads of the laminated strips, too. In this paper a new method is proposed to predict the buckling loads of the laminated strips with...Surface notches lower the stiffness of laminated strips, so they lower the buckling loads of the laminated strips, too. In this paper a new method is proposed to predict the buckling loads of the laminated strips with a surface notch. The theoretical and experimental results show that the buckling loads decrease as the depth or width of the surface notches increase; when the stacking sequence of the laminated strips is [0°/0°/+ θ/-θ/0°/0°/+θ/-θ] s , the buckling load decrease as θ increases. It proves that the method is reliable and significant.展开更多
AIM To study the effect of cholecystokinin-octapeptide（CCK-8）and secretin on contractileactivity of isolated gastric muscle strips inguinea pigs.METHODS Each isolated gastric muscle stripwas suspended in a tissue ch...AIM To study the effect of cholecystokinin-octapeptide（CCK-8）and secretin on contractileactivity of isolated gastric muscle strips inguinea pigs.METHODS Each isolated gastric muscle stripwas suspended in a tissue chamber containing5 mL Krebs solution constantly warmed by waterjacked at 37℃ and supplied with a mixed gas of95% O<sub>2</sub> and 5% CO<sub>2</sub> After incubating for lhunder 1 g tension,varied concentrations of CCK-8 and secretin were added respectively in thetissue chamber and the contractile response wasmeasured isometrically on ink-writing recorders.RESULTS CCK-8 could increase①all regionalcircular and longitudinal muscular tension at rest（fundus LM 19.7%±2.1%,P【0.01;fundus CM16.7%±2.2%,P【0.01;gastric body LM 16.8%±2.3%,P【0.01;body CM 12.7%±2.6%,P【0.01;antrum LM 12.3%±1.3%,P【0.01;antrum CM 16.7%±4.5%,P【0.01;pylous CM12.7%±5.0%,P【0.05）;②contractilefrequencies of body LM,both LM and CM ofantrum and pylorus CM（5.1/min±0.2/min to5.6/min±0.2/min,5.9/min±0.2/min to 6.6/min±0.l/min,5.4/min±0.3/min to 6.3/min±0.4/rain,1.3/min±0.2/min to 2.3/min±0.3/min,respectively,P【0.05）;③the mean contractileamplitude of antral circular muscle（58.6%±18.4%,P【0.05）and ④the motility index ofpylorus CM（145.0%±23.8%,P【0.01）,butdecrease the mean contractile amplitude ofgastric body and antral LM（-10.3%±3.3%,-10.5%±4.6%,respectively,P【0.05）.All the CCK-8 effects were not blocked by atropine orindomethacin.Secretin had no effect on gastricsmooth muscle activity.CONCLUSION CCK-8 possessed bothexcitatory and inhibitory action on contractileactivity of different regions of stomach in guineapigs.Its action was not mediated via cholinergicM receptor and endogenous prostagiandinreceptor,展开更多
Ascites remain the commonest complication of decompensated cirrhosis. Spontaneous bacterial peritonitis (SBP) is defined as the infection of ascitic fluid (AF) in the absence of a contiguous source of infection and/or...Ascites remain the commonest complication of decompensated cirrhosis. Spontaneous bacterial peritonitis (SBP) is defined as the infection of ascitic fluid (AF) in the absence of a contiguous source of infection and/or an intraabdominal inflammatory focus. An AF polymorphonuclear (PMN) leucocyte count ≥ 250/mm 3 -irrespective of the AF culture resultis universally accepted nowadays as the best surrogate marker for diagnosing SBP. Frequently the results of the manual or automated PMN count do not reach the hands of the responsible medical personnel in a timely manner. However, this is a crucial step in SBP management. Since 2000, 26 studies (most of them published as full papers) have checked the validity of using leukocyte esterase reagent strips (LERS) in SBP diagnosis. LERS appear to have low sensitivity for SBP, some LERS types more than others. On the other hand, though, LERS have consistently given a high negative predictive value (> 95% in the majority of the studies) and this supports the use of LERS as a preliminary screening tool for SBP diagnosis. Finally, an AF-tailored dipstick has been developed. Within the proper setting, it is set to become the mainstream process for handling AF samples.展开更多
AIM To study the effects of Dangshen [dried root of Codonopsis Pilosula (Franch) Nannf] on contractile activity of isolated gastric muscle strips in rats and its possible mechanism involved.METHODS Each isolated gastr...AIM To study the effects of Dangshen [dried root of Codonopsis Pilosula (Franch) Nannf] on contractile activity of isolated gastric muscle strips in rats and its possible mechanism involved.METHODS Each isolated gastric muscle strip was put in a tissue chamber containing 5ml Krebs solution, constantly warmed by water jacket at 37℃ and supplied with a mixed gas of 95% O2 and 5% CO2. After incubating for 1h with 1g tension, Dangshen of varied concentration was added cumulatively in the tissue chamber at intervals of 2 minutes. The isometrical response was measured on ink-writing recorders.RESULTS Dangshen dose dependence increased the resting tension of longitudinal muscle (LM) of fundus (r=0.96, P＜0.01), the mean contractile amplitude of circular muscle (CM) of the stomach body (r=0.87, P＜0.05) and CM of antrum (r=0.98, P＜0.01), and the motility index CM of pylorus (r=0.87, P＜0.05). Atropine (5×10-8mol/L) or Hexamethonium (10-5mol/L) or Indomethacin (5×10-7mol/L) was given 2 minutes before the administration of Dangshen, it did not abolish its dose related manner. Atropine apparently reduced the increasing action of 10% and 30% Dangshen on the resting tesion of LM of fundus (P＜0.05), 30%, 100% and 200% Dangshen on bodied strips (P＜0.05), 100% and 200% Dangshen on antral strips (P＜0.05). Hexamethonium reduced the increasing action of 10% and 30% Dangshen on the resting tesion of LM of fundus (P＜0.05 and P＜0.05), 30%, 100% and 200% Dangshen on bodied strips (P＜0.05), and 100% and 200% Dangshen on pyloric strips (P＜0.05). Indomethacin inhibited the effect of 10% Dangshen on the resting tesion of LM of fundus (P＜0.05), but did not affect the exciting action of Dangshen on strips of body, antrum and pylorus.CONCLUSION The results showed that Dangshen possessed exciting action on the isolated gastric smooth muscle strips of the rat. The exciting action of Dangshen was partially mediated via cholinergic M and N receptors.展开更多
AIM: To investigate the effect of rhubarb on contractile response of isolated gallbladder muscle strips from guinea pigs and its mechanism.METHODS: Guinea pigs were killed to remove the whole gallbladder. Two or three...AIM: To investigate the effect of rhubarb on contractile response of isolated gallbladder muscle strips from guinea pigs and its mechanism.METHODS: Guinea pigs were killed to remove the whole gallbladder. Two or three smooth muscle strips (8 mm×3mm) were cut along the longitudinal direction. The mucosa on each strip was carefully removed. Each longitudinal muscle strip was suspended in a tissue chamber containing 5 mL Krebs solution (37 ℃), bubbled continuously with 950 mL/L O2 and 50 mL/L CO2. The resting tension (g), mean contractile amplitude (mm),and contractile frequency (waves/min) were simultaneously recorded on recorders. After 2-h equilibration, rhubarb (10, 20, 70, 200, 700, 1 000 g/L) was added cumulatively to the tissue chamber in turns every 2 min to observe their effects on gallbladder.Antagonists were given 3 min before administration of rhubarb to investigate the possible mechanism.RESULTS: Rhubarb increased the resting tension (from 0 to 0.40±0.02, P＜0.001), and decreased the mean contractile amplitude (from 5.22±0.71 to 2.73±0.41,P＜0.001). It also increased the contractile frequency of the gallbladder muscle strips in guinea pigs (from 4.09±0.46to 6.08±0.35, P＜0.001). The stimulation of rhubarb on the resting tension decreased from 3.98±0.22 to 1.58±0.12by atropine (P＜0.001), from3.98±0.22 to 2.09±0.19 by verapamil (P＜0.001) and from 3.98±0.22 to 2.67±0.43by phentolamine (P＜0.005). But the effect was not inhibited by hexamethonium (P＞0.05). In addition, the action of mean amplitude and frequency was not inhibited by the above antagonists.CONCLUSION: Rhubarb can stimulate the motility of isolated gallbladder muscle strips from guinea pigs. The stimulation of rhubarb might be relevant with M receptor,Ca2+ channel and α receptor partly.展开更多
Double self-adaptive fuzzy PID algorithm-based control strategy was proposed to construct quasi-cascade control system to control the speed of the acid-pickling process of titanium plates and strips. It is very useful...Double self-adaptive fuzzy PID algorithm-based control strategy was proposed to construct quasi-cascade control system to control the speed of the acid-pickling process of titanium plates and strips. It is very useful in overcoming non-linear dynamic behavior, uncertain and time-varying parameters, un-modeled dynamics, and couples between the automatic turbulence control (ATC) and the automatic acid temperature control (AATC) with varying parameters during the operation process. The quasi-cascade control system of inner and outer loop self-adaptive fuzzy PID controller was built, which could effectively control the pickling speed of plates and strips. The simulated results and real application indicate that the plates and strips acid pickling speed control system has good performances of adaptively tracking the parameter variations and anti-disturbances, which ensures the match of acid pickling temperature and turbulence of flowing with acid pickling speed, improving the surface quality of plates and strips acid pickling, and energy efficiency.展开更多
A gas detector 140×140×140 mm^(3)in size,termed the compact active target time projection chamber(CAT-TPC),was developed in this study to measure resonant scattering associated with cluster structures in uns...A gas detector 140×140×140 mm^(3)in size,termed the compact active target time projection chamber(CAT-TPC),was developed in this study to measure resonant scattering associated with cluster structures in unstable nuclei.The CAT-TPC consists of an electronic field cage,double-thick gas-electron-multiplier foils,a general-purpose digital data acquisition system,and a newly developed two-dimensional strip-readout structure.The CAT-TPC was operated using a^(4)He(96%)+CO_(2)(4%)gas mixture at 400 mbar.The working gas also serves as an active target for tracking charged particles.The overall performance of the CAT-TPC was evaluated using a collimated a-particle source.A time resolution of less than 20 ns and a position resolution of less than 0.2 mm were observed along the electron drift direction.Threedimensional images of incident trajectories and scattering events can be clearly reconstructed under an angular resolution of approximately 0.45 degree.展开更多
The chemical compositions and microstructures of the armor strips excavated from the Emperor Qin Shi Huang's mausoleum were examined systematically by using optical microscopy and electron microscopy.It was found ...The chemical compositions and microstructures of the armor strips excavated from the Emperor Qin Shi Huang's mausoleum were examined systematically by using optical microscopy and electron microscopy.It was found that the armor strips were made of pure copper.Based on the morphology of α-Cu recrystal grain and copper sulphide(Cu2S) inclusions in the armor strips,the manufacturing techniques were proposed as follows:smelting pure copper,casting a lamellar plate,forming the cast ingots into sheets through repeated cold forging combined with annealing heat treatment,and finally cutting the sheets into filaments.Furthermore,through the deformation of copper sulphide(Cu2S) inclusions in the strips,the work rate during forging was evaluated and calculated to be close to 75%.展开更多
The two dimensional problem of simply supported laminated isotropic strips with viscoelastic interfaces and under static loading was studied. Exact solution was derived based on the exact elasticity equation and the K...The two dimensional problem of simply supported laminated isotropic strips with viscoelastic interfaces and under static loading was studied. Exact solution was derived based on the exact elasticity equation and the Kelvin-Voigt viscoelastic interfacial model. Numerical computations were performed for a strip consisting of three layers of equal thickness. Results indicated that the response of the laminate was very sensitive to the presence of viscoelastic interfaces.展开更多
Unequal diameter twin-roll casting(UDTRC)can improve the formability,surface conditions,and production efficiency during the fabrication of clad strips.Using Fluent software,a numerical simulation is used to study the...Unequal diameter twin-roll casting(UDTRC)can improve the formability,surface conditions,and production efficiency during the fabrication of clad strips.Using Fluent software,a numerical simulation is used to study the asymmetric heat transfer characteristics of Cu/Al clad strips fabricated by UDTRC.The effects of roller velocity ratio,Cu strip thickness,and inclination angle on the kissing point position,as well as the entire temperature distribution are obtained.The heat transfer model is established,and the mechanism is discussed.The Cu strip and rollers are found to be the main causes of asymmetric heat transfer,indicating that the roller velocity ratio changes the liquid zone proportion in the molten pool.The Cu strip thickness determines the heat absorption capacity and the variations in thermal resistance between the molten Al and the big roller.The inclination angle of the small roller changes the cooling time of big roller to molten Al.Moreover,the microstructure of Al cladding under different roller velocity ratios is examined.The results show significant grain refinement caused by the shear strain along the thickness direction of Al cladding and the intense heat transfer at the moment of contact between the metal Al cladding and Cu strip.展开更多
The following investigations were conducted to evaluate grassy strips of different age for organic arable fields. From September 2009 to October 2010, adult ground beetles were sampled by pitfall traps in three grassy...The following investigations were conducted to evaluate grassy strips of different age for organic arable fields. From September 2009 to October 2010, adult ground beetles were sampled by pitfall traps in three grassy strips (2, 4, and 9 years old), their adjacent cropping areas, their field edges, and a control field (age 0) in Schleswig-Holstein, northern Germany. Carabid assemblages were similar among the fields, strips and edges. Grassy strips and edges had higher species richness and lower activity density than the control field. Activity density increased with increasing distance from the field edge in grassy strips and in the adjacent fields. In cropping areas, species richness andShannon’s H increased with increasing age of strips, whereas evenness and activity density decreased with increasing distance from the field edges. Compared to carnivorous and phytophagous carbides, omnivorous species were affected less by age of strips and distance from field margins. In the strips, species richness of the dominant species increased with age and decreased with distance, but the effect of strip age on species richness was still found in more than150 mfrom the margin. A positive effect of the age of grassy strips on species richness was found for cropping fields, grassy strips and field edges. Old grassy strips also exerted greater influence on the species richness and biodiversity of the adjacent arable fields than the younger strips.展开更多
Asphalt mow strips are typically used as vegetation barriers around guardrail posts in the design of roadside safety structures. Asphalt mow strips have historically been modeled as a rigid layer in simulations;this a...Asphalt mow strips are typically used as vegetation barriers around guardrail posts in the design of roadside safety structures. Asphalt mow strips have historically been modeled as a rigid layer in simulations;this assumption results in significant ground level restraint on the guardrail post. However, experiments have shown that asphalt rupture should be considered in the analysis of the response of guardrail posts embedded in mow strips. The present study investigates the effect of asphalt material properties and mow strip geometry on guardrail post performance using finite element simulations. Numerical simulations are performed and correlated with results from static experiments and material testing. The test simulations and experimental results are used to evaluate the response of guardrail posts with various mow strip designs to predict the level of restraint from the asphalt layer. The model is then used to investigate the effects of asphalt material properties and mow strip geometry on the overall performance of the system. The results demonstrate that including asphalt rupture in numerical simulations is essential in accurately predicting the behavior of guardrail posts installed in asphalt mow strips. In addition, mow strip geometry along with asphalt material properties significantly affect the guardrail post response.展开更多
Electron microscopy and X-ray Energy Dispersive Spectroscopy (XEDS) study on influence of Cu on low carbon hot strips produced by CSP (Compact Strip Production) process has been carried out. The results indicated that...Electron microscopy and X-ray Energy Dispersive Spectroscopy (XEDS) study on influence of Cu on low carbon hot strips produced by CSP (Compact Strip Production) process has been carried out. The results indicated that copper segregation and enrichment at interfacial layer between oxidized surface and steel matrix is the key factor, which results in microcracks and edge flaws on the strips. The primary considerations to prevent detrimental effects from Cu include controlling copper content in proper level, higher soaking temperature and non-oxidizable atmosphere during soaking. Copper sulfide precipitates with nanometers in size were observed, they may be beneficial to the properties of CSP products, and influence of Cu on quality of CSP hot strips is discussed.展开更多
Boiling of water, for purification, commonly practiced in the world, has many problems associated with it like danger of scalding, scaling in the vessels, removal of useful minerals and blandness of taste etc. Water c...Boiling of water, for purification, commonly practiced in the world, has many problems associated with it like danger of scalding, scaling in the vessels, removal of useful minerals and blandness of taste etc. Water can be made safe for drinking simply by heating at 65℃ for 6 minutes. A colour indicating strip was developed which changes colour from red to purple at 67℃. Use of this strip can help in pasteurizing water without the above problems and with considerable energy saving.展开更多
AIM： To observe the effect of Fructus Psoraleae on motility of isolated gallbladder muscle strips of guinea pigs and its mechanism. METHODS： Guinea pigs were hit to lose consciousness and the whole gallbladder was r...AIM： To observe the effect of Fructus Psoraleae on motility of isolated gallbladder muscle strips of guinea pigs and its mechanism. METHODS： Guinea pigs were hit to lose consciousness and the whole gallbladder was removed quickly. Two or three smooth muscle strips （8 mm×3mm） were cut along a longitudinal direction. The mucosa was gently removed. Every longitudinal muscle strip was suspended in a tissue chamber which was continuously perfused with 5 mL Krebs solution （37℃）, pH 7.4, and aerated with 950 mL/L 02 and 50 mL/L CO2. The isometric response was recorded with an ink-writing recorder. After 2 h equilibration under i g-load, 50 μL Fructus Psoraleae （10, 20, 70, 200, 700, 1000 g/L） was added cumulatively into the tissue chamber in turn every 2 rain to observe their effects on gallbladder muscle strips （cumulating final concentration of Fructus Psoraleae was 0.1, 0.3, 1.0, 3.0, 10.0, 20.0 g/L）. The antagonists, including 4-DAMP, benzhydramine, hexamethonium, phentolamine, verapamil and idomethine were given 2 min before Fructus Psoraleae respectively to investigate the mechanisms involved. RESULTS： Fructus Psoraleae dose-dependently increased the resting tension （r=0.992, P〈0.001）, decreased the mean contractile amplitude （r=0.970, P〈0.001） and meanwhile increased the contractile frequency of the gallbladder muscle strip in vitro （r=0.965, P〈0.001）. The exciting action of Fructus Psoraleae on the resting tension could be partially blocked by 4-DAMP （the resting tension decreased from 1.37 ± 0.41 to 0.70 ± 0.35, P〈0.001）, benzhydramine （from 1.37 ±0.41 to 0.45±0.38, P〈0.001）, hexamethonium （from 1.37 ± 0.41 to 0.94 ± 0.23, P〈0.05）, phentolamine （ from 1.37±0.41 to 0.89±0.22, P〈0.01） and verapamil （from 1.37±0.41 to 0.94±0.26, P〈0.05）. But the above antagonists had no significant effect on the action of Fructus Psoraleae-induced mean contractile amplitude （P〉0.05）. Moreover, the increase of the contractile frequency due to Fructus Psoraleae was inhibited by 4-DAMP （decreased from 8.3 ± 1.2 to 6.8 ± 0.5, P 〈 0.01） and hexamethonium （from 8.3 ±1.2 to 7.0 ± 0.9, P 〈 0.05）. Idomethine had no significant effect on the Fructus Psoraleae- induced responses （P〉 0.05）. CONCLUSION： Fructus Psoraleae enhances the motility of isolated gallbladder muscle strips from guinea pigs, in a dose-dependent manner. The effect of Fructus Psoraleae is partly related to M3, N receptor, α receptor, H1 receptor, Ca^2＋ channel, but not related to prostaglandin.展开更多
The piezomagnetic properties of rapidly quenched Fe73.5Cu1Nb3Si13.5B9 alloy strips were investigated in as-quenched state and after annealing for 2 h in vacuum in the temperature range of 100-300 ℃. The impedance of ...The piezomagnetic properties of rapidly quenched Fe73.5Cu1Nb3Si13.5B9 alloy strips were investigated in as-quenched state and after annealing for 2 h in vacuum in the temperature range of 100-300 ℃. The impedance of amorphous strips increases with frequency, and sensitively de-creases with stress increasing, especially in the frequency range of 10-100 MHz. The impedance in-creases approximately linearly with frequency below the critical frequency, but begins to decrease non-linearly with frequency above the critical frequency. The higher the point compressive stress is, the smaller the critical frequency will be. The stability of piezomagnetic properties is very excellent. The impedance of amorphous strips after annealing, especially at 300 ℃, decreases very strongly. The impedance and the absolute values of the sensitive degree of couple layers＇ amorphous strips are lower than those of single layer strips.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.60173039(国家自然科学基金)the Special Foundation of 985 Project of SUN YAT-SEN University of China (中山大学985工程专项资金)
文摘[Objective] This study aimed to compare the detection results of antibodies against infectious bursal disease virus with test strips and agar gel immunodiffusion method. [Method] Antibodies against infectious bursal disease virus in chicken serum were detected using test strips developed in our laboratory, and the results were comparad^with that using traditional agar diffusion method. [Result] The comparative study of the two methods showed that the sensitivity of test strips was eight times over agar gel immunodiffusion; test strips showed higher detection rate in the deter- mination test of 216 clinical samples, with high specificity, easy preservation, and simple and rapid operation, thereby being more suitable for the monitoring of clinical antibodies. [Conclusion] Test strips could replace the existing serological methods, having great promotion and application value in antibody monitoring.
文摘Surface notches lower the stiffness of laminated strips, so they lower the buckling loads of the laminated strips, too. In this paper a new method is proposed to predict the buckling loads of the laminated strips with a surface notch. The theoretical and experimental results show that the buckling loads decrease as the depth or width of the surface notches increase; when the stacking sequence of the laminated strips is [0°/0°/+ θ/-θ/0°/0°/+θ/-θ] s , the buckling load decrease as θ increases. It proves that the method is reliable and significant.
基金the Natural Science Foundation of Gansu Province,No.ZR-94-085.
文摘AIM To study the effect of cholecystokinin-octapeptide（CCK-8）and secretin on contractileactivity of isolated gastric muscle strips inguinea pigs.METHODS Each isolated gastric muscle stripwas suspended in a tissue chamber containing5 mL Krebs solution constantly warmed by waterjacked at 37℃ and supplied with a mixed gas of95% O<sub>2</sub> and 5% CO<sub>2</sub> After incubating for lhunder 1 g tension,varied concentrations of CCK-8 and secretin were added respectively in thetissue chamber and the contractile response wasmeasured isometrically on ink-writing recorders.RESULTS CCK-8 could increase①all regionalcircular and longitudinal muscular tension at rest（fundus LM 19.7%±2.1%,P【0.01;fundus CM16.7%±2.2%,P【0.01;gastric body LM 16.8%±2.3%,P【0.01;body CM 12.7%±2.6%,P【0.01;antrum LM 12.3%±1.3%,P【0.01;antrum CM 16.7%±4.5%,P【0.01;pylous CM12.7%±5.0%,P【0.05）;②contractilefrequencies of body LM,both LM and CM ofantrum and pylorus CM（5.1/min±0.2/min to5.6/min±0.2/min,5.9/min±0.2/min to 6.6/min±0.l/min,5.4/min±0.3/min to 6.3/min±0.4/rain,1.3/min±0.2/min to 2.3/min±0.3/min,respectively,P【0.05）;③the mean contractileamplitude of antral circular muscle（58.6%±18.4%,P【0.05）and ④the motility index ofpylorus CM（145.0%±23.8%,P【0.01）,butdecrease the mean contractile amplitude ofgastric body and antral LM（-10.3%±3.3%,-10.5%±4.6%,respectively,P【0.05）.All the CCK-8 effects were not blocked by atropine orindomethacin.Secretin had no effect on gastricsmooth muscle activity.CONCLUSION CCK-8 possessed bothexcitatory and inhibitory action on contractileactivity of different regions of stomach in guineapigs.Its action was not mediated via cholinergicM receptor and endogenous prostagiandinreceptor,
文摘Ascites remain the commonest complication of decompensated cirrhosis. Spontaneous bacterial peritonitis (SBP) is defined as the infection of ascitic fluid (AF) in the absence of a contiguous source of infection and/or an intraabdominal inflammatory focus. An AF polymorphonuclear (PMN) leucocyte count ≥ 250/mm 3 -irrespective of the AF culture resultis universally accepted nowadays as the best surrogate marker for diagnosing SBP. Frequently the results of the manual or automated PMN count do not reach the hands of the responsible medical personnel in a timely manner. However, this is a crucial step in SBP management. Since 2000, 26 studies (most of them published as full papers) have checked the validity of using leukocyte esterase reagent strips (LERS) in SBP diagnosis. LERS appear to have low sensitivity for SBP, some LERS types more than others. On the other hand, though, LERS have consistently given a high negative predictive value (> 95% in the majority of the studies) and this supports the use of LERS as a preliminary screening tool for SBP diagnosis. Finally, an AF-tailored dipstick has been developed. Within the proper setting, it is set to become the mainstream process for handling AF samples.
文摘AIM To study the effects of Dangshen [dried root of Codonopsis Pilosula (Franch) Nannf] on contractile activity of isolated gastric muscle strips in rats and its possible mechanism involved.METHODS Each isolated gastric muscle strip was put in a tissue chamber containing 5ml Krebs solution, constantly warmed by water jacket at 37℃ and supplied with a mixed gas of 95% O2 and 5% CO2. After incubating for 1h with 1g tension, Dangshen of varied concentration was added cumulatively in the tissue chamber at intervals of 2 minutes. The isometrical response was measured on ink-writing recorders.RESULTS Dangshen dose dependence increased the resting tension of longitudinal muscle (LM) of fundus (r=0.96, P＜0.01), the mean contractile amplitude of circular muscle (CM) of the stomach body (r=0.87, P＜0.05) and CM of antrum (r=0.98, P＜0.01), and the motility index CM of pylorus (r=0.87, P＜0.05). Atropine (5×10-8mol/L) or Hexamethonium (10-5mol/L) or Indomethacin (5×10-7mol/L) was given 2 minutes before the administration of Dangshen, it did not abolish its dose related manner. Atropine apparently reduced the increasing action of 10% and 30% Dangshen on the resting tesion of LM of fundus (P＜0.05), 30%, 100% and 200% Dangshen on bodied strips (P＜0.05), 100% and 200% Dangshen on antral strips (P＜0.05). Hexamethonium reduced the increasing action of 10% and 30% Dangshen on the resting tesion of LM of fundus (P＜0.05 and P＜0.05), 30%, 100% and 200% Dangshen on bodied strips (P＜0.05), and 100% and 200% Dangshen on pyloric strips (P＜0.05). Indomethacin inhibited the effect of 10% Dangshen on the resting tesion of LM of fundus (P＜0.05), but did not affect the exciting action of Dangshen on strips of body, antrum and pylorus.CONCLUSION The results showed that Dangshen possessed exciting action on the isolated gastric smooth muscle strips of the rat. The exciting action of Dangshen was partially mediated via cholinergic M and N receptors.
基金Supported by the Key Laboratory of Pre-clinical Research for Chinese HerbsNew Drugs of Gansu Province and The Natural Scientific Foundation of Gansu Province, No. zs021-A25-059-Y
文摘AIM: To investigate the effect of rhubarb on contractile response of isolated gallbladder muscle strips from guinea pigs and its mechanism.METHODS: Guinea pigs were killed to remove the whole gallbladder. Two or three smooth muscle strips (8 mm×3mm) were cut along the longitudinal direction. The mucosa on each strip was carefully removed. Each longitudinal muscle strip was suspended in a tissue chamber containing 5 mL Krebs solution (37 ℃), bubbled continuously with 950 mL/L O2 and 50 mL/L CO2. The resting tension (g), mean contractile amplitude (mm),and contractile frequency (waves/min) were simultaneously recorded on recorders. After 2-h equilibration, rhubarb (10, 20, 70, 200, 700, 1 000 g/L) was added cumulatively to the tissue chamber in turns every 2 min to observe their effects on gallbladder.Antagonists were given 3 min before administration of rhubarb to investigate the possible mechanism.RESULTS: Rhubarb increased the resting tension (from 0 to 0.40±0.02, P＜0.001), and decreased the mean contractile amplitude (from 5.22±0.71 to 2.73±0.41,P＜0.001). It also increased the contractile frequency of the gallbladder muscle strips in guinea pigs (from 4.09±0.46to 6.08±0.35, P＜0.001). The stimulation of rhubarb on the resting tension decreased from 3.98±0.22 to 1.58±0.12by atropine (P＜0.001), from3.98±0.22 to 2.09±0.19 by verapamil (P＜0.001) and from 3.98±0.22 to 2.67±0.43by phentolamine (P＜0.005). But the effect was not inhibited by hexamethonium (P＞0.05). In addition, the action of mean amplitude and frequency was not inhibited by the above antagonists.CONCLUSION: Rhubarb can stimulate the motility of isolated gallbladder muscle strips from guinea pigs. The stimulation of rhubarb might be relevant with M receptor,Ca2+ channel and α receptor partly.
基金Project(51090385) supported by the National Natural Science Foundation of ChinaProject(2001IB001) supported by Yunnan Provincial Science and Technology Fund, China
文摘Double self-adaptive fuzzy PID algorithm-based control strategy was proposed to construct quasi-cascade control system to control the speed of the acid-pickling process of titanium plates and strips. It is very useful in overcoming non-linear dynamic behavior, uncertain and time-varying parameters, un-modeled dynamics, and couples between the automatic turbulence control (ATC) and the automatic acid temperature control (AATC) with varying parameters during the operation process. The quasi-cascade control system of inner and outer loop self-adaptive fuzzy PID controller was built, which could effectively control the pickling speed of plates and strips. The simulated results and real application indicate that the plates and strips acid pickling speed control system has good performances of adaptively tracking the parameter variations and anti-disturbances, which ensures the match of acid pickling temperature and turbulence of flowing with acid pickling speed, improving the surface quality of plates and strips acid pickling, and energy efficiency.
基金supported by the National Key R&D Program of China(No.2018YFA0404403)the National Natural Science Foundation of China(Nos.U1967201,11875074,11875073,and 11961141003)the State Key Laboratory of Nuclear Physics and Technology,PKU(No.NPT2020KFY06)。
文摘A gas detector 140×140×140 mm^(3)in size,termed the compact active target time projection chamber(CAT-TPC),was developed in this study to measure resonant scattering associated with cluster structures in unstable nuclei.The CAT-TPC consists of an electronic field cage,double-thick gas-electron-multiplier foils,a general-purpose digital data acquisition system,and a newly developed two-dimensional strip-readout structure.The CAT-TPC was operated using a^(4)He(96%)+CO_(2)(4%)gas mixture at 400 mbar.The working gas also serves as an active target for tracking charged particles.The overall performance of the CAT-TPC was evaluated using a collimated a-particle source.A time resolution of less than 20 ns and a position resolution of less than 0.2 mm were observed along the electron drift direction.Threedimensional images of incident trajectories and scattering events can be clearly reconstructed under an angular resolution of approximately 0.45 degree.
文摘The chemical compositions and microstructures of the armor strips excavated from the Emperor Qin Shi Huang's mausoleum were examined systematically by using optical microscopy and electron microscopy.It was found that the armor strips were made of pure copper.Based on the morphology of α-Cu recrystal grain and copper sulphide(Cu2S) inclusions in the armor strips,the manufacturing techniques were proposed as follows:smelting pure copper,casting a lamellar plate,forming the cast ingots into sheets through repeated cold forging combined with annealing heat treatment,and finally cutting the sheets into filaments.Furthermore,through the deformation of copper sulphide(Cu2S) inclusions in the strips,the work rate during forging was evaluated and calculated to be close to 75%.
文摘The two dimensional problem of simply supported laminated isotropic strips with viscoelastic interfaces and under static loading was studied. Exact solution was derived based on the exact elasticity equation and the Kelvin-Voigt viscoelastic interfacial model. Numerical computations were performed for a strip consisting of three layers of equal thickness. Results indicated that the response of the laminate was very sensitive to the presence of viscoelastic interfaces.
基金Project(51974278)supported by the National Natural Science Foundation of ChinaProject(E2018203446)supported by the Natural Science Foundation of Hebei Province Distinguished Young Fund Project,ChinaProject(2018YFA0707303)supported by the National Key Research and Development Project of China。
文摘Unequal diameter twin-roll casting(UDTRC)can improve the formability,surface conditions,and production efficiency during the fabrication of clad strips.Using Fluent software,a numerical simulation is used to study the asymmetric heat transfer characteristics of Cu/Al clad strips fabricated by UDTRC.The effects of roller velocity ratio,Cu strip thickness,and inclination angle on the kissing point position,as well as the entire temperature distribution are obtained.The heat transfer model is established,and the mechanism is discussed.The Cu strip and rollers are found to be the main causes of asymmetric heat transfer,indicating that the roller velocity ratio changes the liquid zone proportion in the molten pool.The Cu strip thickness determines the heat absorption capacity and the variations in thermal resistance between the molten Al and the big roller.The inclination angle of the small roller changes the cooling time of big roller to molten Al.Moreover,the microstructure of Al cladding under different roller velocity ratios is examined.The results show significant grain refinement caused by the shear strain along the thickness direction of Al cladding and the intense heat transfer at the moment of contact between the metal Al cladding and Cu strip.
文摘The following investigations were conducted to evaluate grassy strips of different age for organic arable fields. From September 2009 to October 2010, adult ground beetles were sampled by pitfall traps in three grassy strips (2, 4, and 9 years old), their adjacent cropping areas, their field edges, and a control field (age 0) in Schleswig-Holstein, northern Germany. Carabid assemblages were similar among the fields, strips and edges. Grassy strips and edges had higher species richness and lower activity density than the control field. Activity density increased with increasing distance from the field edge in grassy strips and in the adjacent fields. In cropping areas, species richness andShannon’s H increased with increasing age of strips, whereas evenness and activity density decreased with increasing distance from the field edges. Compared to carnivorous and phytophagous carbides, omnivorous species were affected less by age of strips and distance from field margins. In the strips, species richness of the dominant species increased with age and decreased with distance, but the effect of strip age on species richness was still found in more than150 mfrom the margin. A positive effect of the age of grassy strips on species richness was found for cropping fields, grassy strips and field edges. Old grassy strips also exerted greater influence on the species richness and biodiversity of the adjacent arable fields than the younger strips.
文摘Asphalt mow strips are typically used as vegetation barriers around guardrail posts in the design of roadside safety structures. Asphalt mow strips have historically been modeled as a rigid layer in simulations;this assumption results in significant ground level restraint on the guardrail post. However, experiments have shown that asphalt rupture should be considered in the analysis of the response of guardrail posts embedded in mow strips. The present study investigates the effect of asphalt material properties and mow strip geometry on guardrail post performance using finite element simulations. Numerical simulations are performed and correlated with results from static experiments and material testing. The test simulations and experimental results are used to evaluate the response of guardrail posts with various mow strip designs to predict the level of restraint from the asphalt layer. The model is then used to investigate the effects of asphalt material properties and mow strip geometry on the overall performance of the system. The results demonstrate that including asphalt rupture in numerical simulations is essential in accurately predicting the behavior of guardrail posts installed in asphalt mow strips. In addition, mow strip geometry along with asphalt material properties significantly affect the guardrail post response.
文摘Electron microscopy and X-ray Energy Dispersive Spectroscopy (XEDS) study on influence of Cu on low carbon hot strips produced by CSP (Compact Strip Production) process has been carried out. The results indicated that copper segregation and enrichment at interfacial layer between oxidized surface and steel matrix is the key factor, which results in microcracks and edge flaws on the strips. The primary considerations to prevent detrimental effects from Cu include controlling copper content in proper level, higher soaking temperature and non-oxidizable atmosphere during soaking. Copper sulfide precipitates with nanometers in size were observed, they may be beneficial to the properties of CSP products, and influence of Cu on quality of CSP hot strips is discussed.
文摘Boiling of water, for purification, commonly practiced in the world, has many problems associated with it like danger of scalding, scaling in the vessels, removal of useful minerals and blandness of taste etc. Water can be made safe for drinking simply by heating at 65℃ for 6 minutes. A colour indicating strip was developed which changes colour from red to purple at 67℃. Use of this strip can help in pasteurizing water without the above problems and with considerable energy saving.
基金Supported by Key Laboratory of Pre-clinical Study for New Drugs of Gansu Province and the Natural Science Foundation of Gansu Province, No.ZS021-A25-059-Y
文摘AIM： To observe the effect of Fructus Psoraleae on motility of isolated gallbladder muscle strips of guinea pigs and its mechanism. METHODS： Guinea pigs were hit to lose consciousness and the whole gallbladder was removed quickly. Two or three smooth muscle strips （8 mm×3mm） were cut along a longitudinal direction. The mucosa was gently removed. Every longitudinal muscle strip was suspended in a tissue chamber which was continuously perfused with 5 mL Krebs solution （37℃）, pH 7.4, and aerated with 950 mL/L 02 and 50 mL/L CO2. The isometric response was recorded with an ink-writing recorder. After 2 h equilibration under i g-load, 50 μL Fructus Psoraleae （10, 20, 70, 200, 700, 1000 g/L） was added cumulatively into the tissue chamber in turn every 2 rain to observe their effects on gallbladder muscle strips （cumulating final concentration of Fructus Psoraleae was 0.1, 0.3, 1.0, 3.0, 10.0, 20.0 g/L）. The antagonists, including 4-DAMP, benzhydramine, hexamethonium, phentolamine, verapamil and idomethine were given 2 min before Fructus Psoraleae respectively to investigate the mechanisms involved. RESULTS： Fructus Psoraleae dose-dependently increased the resting tension （r=0.992, P〈0.001）, decreased the mean contractile amplitude （r=0.970, P〈0.001） and meanwhile increased the contractile frequency of the gallbladder muscle strip in vitro （r=0.965, P〈0.001）. The exciting action of Fructus Psoraleae on the resting tension could be partially blocked by 4-DAMP （the resting tension decreased from 1.37 ± 0.41 to 0.70 ± 0.35, P〈0.001）, benzhydramine （from 1.37 ±0.41 to 0.45±0.38, P〈0.001）, hexamethonium （from 1.37 ± 0.41 to 0.94 ± 0.23, P〈0.05）, phentolamine （ from 1.37±0.41 to 0.89±0.22, P〈0.01） and verapamil （from 1.37±0.41 to 0.94±0.26, P〈0.05）. But the above antagonists had no significant effect on the action of Fructus Psoraleae-induced mean contractile amplitude （P〉0.05）. Moreover, the increase of the contractile frequency due to Fructus Psoraleae was inhibited by 4-DAMP （decreased from 8.3 ± 1.2 to 6.8 ± 0.5, P 〈 0.01） and hexamethonium （from 8.3 ±1.2 to 7.0 ± 0.9, P 〈 0.05）. Idomethine had no significant effect on the Fructus Psoraleae- induced responses （P〉 0.05）. CONCLUSION： Fructus Psoraleae enhances the motility of isolated gallbladder muscle strips from guinea pigs, in a dose-dependent manner. The effect of Fructus Psoraleae is partly related to M3, N receptor, α receptor, H1 receptor, Ca^2＋ channel, but not related to prostaglandin.
基金Funded by the National Natural Science Foundation of China (No.0576014)
文摘The piezomagnetic properties of rapidly quenched Fe73.5Cu1Nb3Si13.5B9 alloy strips were investigated in as-quenched state and after annealing for 2 h in vacuum in the temperature range of 100-300 ℃. The impedance of amorphous strips increases with frequency, and sensitively de-creases with stress increasing, especially in the frequency range of 10-100 MHz. The impedance in-creases approximately linearly with frequency below the critical frequency, but begins to decrease non-linearly with frequency above the critical frequency. The higher the point compressive stress is, the smaller the critical frequency will be. The stability of piezomagnetic properties is very excellent. The impedance of amorphous strips after annealing, especially at 300 ℃, decreases very strongly. The impedance and the absolute values of the sensitive degree of couple layers＇ amorphous strips are lower than those of single layer strips.
