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Design and Characterization of an Aerosol Test Chamber for Emergency Response Patient Contamination Control Simulation and Research
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作者 Megan L. Steele Emily M. Spatz +4 位作者 George P. Lemmer Jacob M. Denney Jeremy M. Slagley Casey W. Cooper Robert M. Eninger 《Occupational Diseases and Environmental Medicine》 2023年第1期78-96,共19页
Contaminated or infected patients present a risk of cross-contamination for emergency responders, attending medical personnel and medical facilities as they enter a treatment facility. The controlled conditions of an ... Contaminated or infected patients present a risk of cross-contamination for emergency responders, attending medical personnel and medical facilities as they enter a treatment facility. The controlled conditions of an aerosol test chamber are required to examine factors of contamination, decontamination, and cross-contamination. This study presents the design, construction, and a method for characterizing an aerosol test chamber for a full-sized manikin on a standard North Atlantic Treaty Organization litter. The methodology combined air velocity measurements, aerosol particle counts and size distributions, and computational fluid dynamics modeling to describe the chamber’s performance in three dimensions. This detailed characterization facilitates future experimental design by predicting chamber performance for a variety of patient-focused research. 展开更多
关键词 Test chamber Characterization Aerosol Generation Exposure chamber Design Air Velocity Mapping Spatial Variability CFD Modeling Patient Decontamination
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A heterogeneous double chamber electro-Fenton with high production of H_(2)O_(2) using La–CeO_(2) modified graphite felt as cathode 被引量:1
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作者 Suhang Jiang Lijuan Tan +2 位作者 Yujia Tong Lijian Shi Weixing Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期98-105,共8页
Hydrogen peroxide synthesis by electro-reduction of O_(2) to substitute the current anthraquinone process has attracted a great deal of attention. Low oxygen utilization rate and low hydrogen peroxide production remai... Hydrogen peroxide synthesis by electro-reduction of O_(2) to substitute the current anthraquinone process has attracted a great deal of attention. Low oxygen utilization rate and low hydrogen peroxide production remain obstacles to electro-Fenton application. In situ H_(2)O_(2) generated by electrochemical reaction depends on the electrochemical performance of the cathode and the structure of the reactor. Here, novel graphite felt(GF) modified by La-doped CeO_(2)(La-CeO_(2)) was developed as a cathode. A new double chamber electro-Fenton reactor was proposed, where an organic ultrafiltration membrane was used to prevent H_(2)O_(2) from spreading to the anode. The effects of hydrothermal temperature, time and urea concentration on the electrochemical properties of graphite felt were investigated. The accumulated concentration of H_(2)O_(2) on the modified cathode reached 218.4 mg·L^(-1)in 1 h when the optimal conditions of hydrothermal temperature 120 ℃ and urea concentration 0.55%(mass) in 24 h. The degradation rate of methyl orange reached 98.29%. The new electro-Fenton reactor can efficiently produce hydrogen peroxide to degrade various organic substances and has a high potential for treating wastewater in the chemical industry. 展开更多
关键词 Hydrogen peroxide Graphite felt modification Double chamber reactor Organic ultrafiltration membrane
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Axial length and anterior chamber indices in elderly population: Tehran Geriatric Eye Study
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作者 Hassan Hashemi Samira Heydarian +1 位作者 Alireza Hashemi Mehdi Khabazkhoob 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第11期1876-1882,共7页
AIM:To determine the normative distribution of axial length(AL),anterior chamber depth(ACD),anterior chamber volume(ACV),anterior chamber angle(ACA),and some of their associated factors in subjects aged 60 and over.ME... AIM:To determine the normative distribution of axial length(AL),anterior chamber depth(ACD),anterior chamber volume(ACV),anterior chamber angle(ACA),and some of their associated factors in subjects aged 60 and over.METHODS:In this cross-sectional study,160 clusters were sampled using multi-stage cluster sampling in Tehran,Iran.After a preliminary interview,the participants underwent optometric examinations including visual acuity and refraction measurement followed by slit lamp biomicroscopy.Finally,ocular imaging was done using the Pentacam AXL to measure AL,ACD,ACV,and ACA.RESULTS:A total of 4519 eyes of 2436 participants were evaluated,of whom 58.0%(n=1412)were female.The mean age of the subjects was 67.32±6.05y(range:60-95y).The mean AL,ACD,ACV,and ACA was 23.22 mm(23.18-23.27 mm),2.61 mm(2.59-2.62 mm),126.56 mm3(125.08-128.04 mm3),and 30.61°(30.3°-30.92°),respectively.In the multivariable model,after adjusting for the effect of both eyes,the longest and shortest AL was seen in myopic and hyperopic subjects,respectively.AL,ACD,ACV and ACA were significantly larger in men compared to women(P<0.001).Except ACA,other evaluated parameters showed an inverse correlation with age(P<0.001),however,this correlation was insignificant for AL(P=0.623).CONCLUSION:Normative value of AL,and other biometric parameters are specific for each ethnicity,age and sex group.Any alteration in these parameters and their effect on refraction should be considered in this age group,especially in case of cataract surgery. 展开更多
关键词 BIOMETRY ELDERLY axial length anterior chamber depth
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Measuring^(222)Rn in aquatic environment via Pulsed Ionization Chamber Radon Detector
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作者 Lijun Song Wen Liu +4 位作者 Shibin Zhao Chunqian Li Jinjia Guo Natasha Dimova Bochao Xu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期185-189,I0001-I0006,共11页
Radon(Rn)is a naturally occurring radioactive inert gas in nature,and^(222)Rn has been routinely used as a powerful tracer in various aquatic environmental research on timescales of hours to days,such as submarine gro... Radon(Rn)is a naturally occurring radioactive inert gas in nature,and^(222)Rn has been routinely used as a powerful tracer in various aquatic environmental research on timescales of hours to days,such as submarine groundwater discharge.Here we developed a new approach to measure^(222)Rn in discrete water samples with a wide range of^(222)Rn concentrations using a Pulsed Ionization Chamber(PIC)Radon Detector.The sensitivity of the new PIC system is evaluated at 6.06 counts per minute for 1 Bq/L when a 500 mL water sample volume is used.A robust logarithmic correlation between sample volumes,ranging from 250 mL to 5000 mL,and system sensitivity obtained in this study strongly suggests that this approach is suitable for measuring radon concentration levels in various natural waters.Compared to the currently available methods for measuring radon in grab samples,the PIC system is cheaper,easier to operate and does not require extra accessories(e.g.,drying tubes etc.)to maintain stable measurements throughout the counting procedure. 展开更多
关键词 ^(222)Rn radon measurement Pulsed Ionization chamber Radon Detector radon in discrete water samples submarine groundwater discharge
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Effect of low dose laser cycloplasty on deepening anterior chamber in chronic angle-closure glaucoma
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作者 Xuan-Li Zheng Hai-Shuang Lin +4 位作者 Xiao-Jie Wang Jia-Qian Li Yan-Qian Xie Shao-Dan Zhang Yuan-Bo Liang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第12期2011-2017,共7页
AIM:To describe the outcome of using low-dose laser cycloplasty(LCP)in chronic angle-closure glaucoma(CACG).METHODS:A retrospective case series.Medical charts of CACG patients who underwent LCP in the Eye Hospital of ... AIM:To describe the outcome of using low-dose laser cycloplasty(LCP)in chronic angle-closure glaucoma(CACG).METHODS:A retrospective case series.Medical charts of CACG patients who underwent LCP in the Eye Hospital of Wenzhou Medical University were reviewed.The main outcomes included intraocular pressure(IOP),the number of glaucoma medication,anterior segment parameters and surgery-related complications.RESULTS:A total of 7 eyes of 7 CACG patients(age 38.9±11.0y)underwent LCP with a mean follow-up of 27.1±13.7mo(range 16-48mo).Following LCP,mean IOP and glaucoma medications decreased from 26.1±6.1 mm Hg with 3.1±1.1 glaucoma medications pre-treatment to 14.9±3.1 mm Hg(P=0.027)with 0.4±1.1 glaucoma medications(P=0.001)at final follow-up.The anterior chamber depth(ACD),angle opening distance500 and trabecular-iris angle increased from 1.65±0.33 mm,0.05 mm(range 0-0.30 mm)and 5.1°(range,0-31.97°)at baseline to 1.98±0.43 mm(P=0.073),0.53 mm(range 0.42-0.91 mm,P=0.015),45.9°(range,40.2°-59.4°),(P=0.015)in the long-term follow-up,respectively.The deepening of ACD and reopening of anterior chamber angle(ACA)was observed in 6 eyes(85.7%).CONCLUSION:LCP is a promising treatment option for patients with CACG via reducing IOP and glaucoma medication without serious complications.In addition,LCP can bring a significant deepening in ACD and reopening of ACA. 展开更多
关键词 chronic angle-closure glaucoma low dose laser cycloplasty anterior chamber depth intraocular pressure
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Axial length,vitreoretinal pathology,and anterior chamber depth can predict postoperative refractive outcomes in phacovitrectomy/silicone oil removal
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作者 Xu Chen He Zhao +6 位作者 Jia-Yun Ren Lu Wang Jun-Li Wan Bo Liu Nan Wu Xi Liu Yong Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第4期554-562,共9页
AIM:To evaluate the postoperative refractive prediction error(PE)and determine the factors that af fect the refractive outcomes of combined pars plana vitrectomy(PPV)or silicone oil removal(SOR)with cataract surgery.M... AIM:To evaluate the postoperative refractive prediction error(PE)and determine the factors that af fect the refractive outcomes of combined pars plana vitrectomy(PPV)or silicone oil removal(SOR)with cataract surgery.METHODS:The study is a retrospective,case-series study.Totally 301 eyes of 301 patients undergoing combined PPV/SOR with cataract surgery were enrolled.Eligible individuals were separated into four groups according to their preoperative diagnoses:silicone oil-filled eyes after PPV(group 1),epiretinal membrane(group 2),macular hole(group 3),and primary retinal detachment(RD;group 4).The variables af fecting postoperative refractive outcomes were analyzed,including age,gender,preoperative best-corrected visual acuity(BCVA),axial length(AL),keratometry average,anterior chamber depth(ACD),intraocular tamponade,and vitreoretinal pathology.The outcome measurements include the mean refractive PE and the proportions of eyes with a PE within±0.50 diopter(D)and±1.00 D.RESULTS:For all patients,the mean PE was-0.04±1.17 D,and 50.17%of patients(eyes)had a PE within±0.50 D.There was a significant difference in refractive outcomes among the four groups(P=0.028),with RD(group 4)showing the least favorable refractive outcome.In multivariate regression analysis,only AL,vitreoretinal pathology,and ACD were strongly associated with PE(all P<0.01).Univariate analysis revealed that longer eyes(AL>26 mm)and a deeper ACD were correlated with hyperopic PE,and shorter eyes(AL<26 mm)and a shallower ACD were correlated with myopic PE.CONCLUSION:RD patients have the least favorable refractive outcome.AL,vitreoretinal pathology,and ACD are strongly associated with PE in the combined surgery.These three factors affect refractive outcomes and thus can be used to predict a better postoperative refractive outcome in clinical practice. 展开更多
关键词 axial length vitreoretinal pathology anterior chamber depth intraocular lens pars plana vitrectomy silicone oil removal CATARACT combined surgery refractive error intraocular tamponade
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Design and Structure Optimization of Plenum Chamber with Airfoil Baffle to Improve Its Outlet Velocity Uniformity in Heat Setting Machines
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作者 钱淼 魏鹏郦 +2 位作者 林子杰 向忠 胡旭东 《Journal of Donghua University(English Edition)》 CAS 2023年第5期515-524,共10页
The plenum chamber of a heat setting machine is a key structure for distributing hot air to different air channels.Its outlet velocity uniformity directly determines the heating uniformity of textiles,significantly af... The plenum chamber of a heat setting machine is a key structure for distributing hot air to different air channels.Its outlet velocity uniformity directly determines the heating uniformity of textiles,significantly affecting the heat setting performance.In a traditional heat setting machine,the outlet airflow maldistribution of the plenum chamber still exists.In this study,a novel plenum chamber with an airfoil baffle was established to improve the uniformity of the velocity distribution at the outlet in a heat setting machine.The structural influence of the plenum chamber on the velocity distribution was investigated using a computational fluid dynamics program.It was found that a chamber with a smaller outlet partition thickness had a better outlet velocity uniformity.The structural optimization of the plenum chamber was conducted using the particle swarm optimization algorithm.The outlet partition thickness,the transverse distance and the longitudinal distance of the optimized plenum chamber were 20,686.2 and 274.6 mm,respectively.Experiments were carried out.The experimental and simulated results showed that the optimized plenum chamber with an airfoil baffle could improve the outlet velocity uniformity.The air outlet velocity uniformity index of the optimized plenum chamber with an airfoil baffle was 4.75%higher than that of the plenum chamber without an airfoil baffle and 5.98%higher than that of the conventional chamber with a square baffle in a commercial heat setting machine. 展开更多
关键词 velocity distribution uniformity structure optimization numerical simulation AIRFOIL plenum chamber heat setting
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Biophysical warming patterns of an open-top chamber and its short-term influence on a Phragmites wetland ecosystem in China
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作者 Xue-yang Yu Si-yuan Ye +4 位作者 Li-xin Pei Liu-juan Xie Ken W.Krauss Samantha K.Chapman Hans Brix 《China Geology》 CAS CSCD 2023年第4期594-610,共17页
Passive-warming, open-top chambers(OTCs) are widely applied for studying the effects of future climate warming on coastal wetlands. In this study, a set of six OTCs were established at a Phragmites wetland located in ... Passive-warming, open-top chambers(OTCs) are widely applied for studying the effects of future climate warming on coastal wetlands. In this study, a set of six OTCs were established at a Phragmites wetland located in the Yellow River Delta of Dongying City, China. With data collected through online transmission and in-situ sensors, the attributes and patterns of realized OTCs warming are demonstrated.The authors also quantified the preliminary influence of experimental chamber warming on plant traits.OTCs produced an elevated average air temperature of 0.8°C(relative to controls) during the growing season(June to October) of 2018, and soil temperatures actually decreased by 0.54°C at a depth of 5 cm and 0.46°C at a depth of 30 cm in the OTCs. Variations in diel patterns of warming depend greatly on the heat sources of incoming radiation in the daytime versus soil heat flux at night. Warming effects were often larger during instantaneous analyses and influenced OTCs air temperatures from-2.5°C to 8.3°C dependent on various meteorological conditions at any given time, ranging from cooling influences from vertical heat exchange and vegetation to radiation-associated warming. Night-time temperature depressions in the OTCs were due to the low turbulence inside OTCs and changes in surface soilatmosphere heat transfer. Plant shoot density, basal diameter, and biomass of Phragmites decreased by23.2%, 6.3%, and 34.0%, respectively, under experimental warming versus controls, and plant height increased by 4.3%, reflecting less carbon allocation to stem structures as plants in the OTCs experienced simultaneous wind buffering. While these passive-warming OTCs created the desired warming effects both to the atmosphere and soils, pest damages on the plant leaves and lodging within the OTCs were extensive and serious, creating the need to consider control options for these chambers and the replicated OTCs studies underway in other Chinese Phragmites marshes(Panjin and Yancheng). 展开更多
关键词 Open-top chambers(OTCs)warming Phragmites australis wetland Short-term ecosystem impact Climate warming Soil heat flux Soil-atmosphere heat transfer Ecological geological engineering Hydrogeological engineering Yellow River Delta
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Anterior Chamber Depth Changes in Narrow Iridocorneal Angles after Phacoemulsification
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作者 Md. Ariful Islam Abir Bin Sajj +2 位作者 Tohura Sharmin Md. Sanwar Hossain Md. Shafiqul Islam 《Open Journal of Ophthalmology》 2023年第2期187-198,共12页
Background: The burden of cataract and glaucoma has been increasing. Primary angle closure occurs as a result of crowded anterior segment anatomy causing appositional contact between peripheral iris and trabecular mes... Background: The burden of cataract and glaucoma has been increasing. Primary angle closure occurs as a result of crowded anterior segment anatomy causing appositional contact between peripheral iris and trabecular meshwork. Lens extraction has been proposed as a method of deepening anterior chamber and managing intraocular pressure. Purpose: To assess changes in anterior chamber depth after phacoemulsification with intraocular lens implantation in narrow angle eyes. Design: Prospective controlled trial (before-after) study. Method: The study was conducted from March 2015 to August 2017 among the patients of department of Ophthalmology of BSMMU who were diagnosed as cataract with narrow angles. Anterior chamber angle grading of 2 or less (Shaffer grading) in 3 or more quadrants was considered narrow angle (NA). The purposive type sampling technique was applied to collect sample from the study population, as per inclusion and exclusion criteria. Complete clinical evaluation including history, physical examination, relevant ocular examinations and systemic examinations were performed. In this prospective study, subjects underwent phacoemulsification with foldable lens implantation. A scan ultrasonography was performed preoperatively and 10<sup>th</sup> and 30<sup>th</sup> postoperative days of surgery. Results: Thirty eyes of 29 patients included in the study, male: female ratio was 1:1, with an overall mean age of 62.03 ± 8.95 years. The mean preoperative central ACD was 2.95 ± 0.35 mm. At 10<sup>th</sup> and 30<sup>th</sup> POD mean central ACD were 3.94 ± 0.32, and 3.92 ± 0.28 mm respectively. Mean of increase in central ACD at final follow-up was 0.96 mm (p Conclusion: Phacoemulsification with posterior chamber in bag lens implantation can deepen the anterior chamber depth in patients with narrow angles. Based on these findings, it is concluded that phacoemulsification with foldable intraocular lens implantation is an effective tool in deepening the anterior chamber. 展开更多
关键词 Anterior chamber Depth PHACOEMULSIFICATION Iridocorneal Angles Open Angle Narrow Angle
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Current Status of Rn-220 Chamber Carrier Aerosol Modulation Research
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作者 Yanan Liu Yu Cheng 《Journal of Geoscience and Environment Protection》 2023年第4期30-36,共7页
Radon is the most important source of natural radiation to human beings and the second major causative agent of lung cancer other than smoking. In recent years, the hazards of human exposure to thoron (Rn-220), anothe... Radon is the most important source of natural radiation to human beings and the second major causative agent of lung cancer other than smoking. In recent years, the hazards of human exposure to thoron (Rn-220), another isotope of radon, and its progeny have gained consensus. To accurately evaluate the dose level and hazards of Rn-220 and its progeny, a standard Rn-220 chamber with strong regulation ability for Rn-220 and its progeny needs to be established for the scale or calibration of measurement instruments. This paper describes the hazards, sources, behavioral characteristics of Rn-220 and its progeny, and some representative Rn-220 chambers established in various countries. 展开更多
关键词 THORON Rn-220 chamber Aerosol Modulation
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罗丹明123经大鼠空肠黏膜的体外Ussing chamber渗透研究 被引量:4
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作者 黄蓓蓓 任非 +3 位作者 李国锋 王春霞 李亦蕾 孙亚彬 《中国医院药学杂志》 CAS CSCD 北大核心 2008年第17期1440-1442,共3页
目的:检测并评价罗丹明123(R123)经空肠黏膜渗透的特点,分析此法的可行性。方法:配制R123溶液,采用体外Ussing chamber实验法,考察R123经时经大鼠空肠黏膜吸收方向和分泌方向的累计透过量,并计算各自渗透系数。结果:R123吸收和分泌方向... 目的:检测并评价罗丹明123(R123)经空肠黏膜渗透的特点,分析此法的可行性。方法:配制R123溶液,采用体外Ussing chamber实验法,考察R123经时经大鼠空肠黏膜吸收方向和分泌方向的累计透过量,并计算各自渗透系数。结果:R123吸收和分泌方向的表观渗透系数Papp(×10-5,cm.s-1)分别为(1.9±1.3)和(7.4±5.2),差异具显著性。结论:R123作为P-糖蛋白的底物,其经肠黏膜渗透以分泌方向为主;Ussing chamber实验用于评价药物在肠道内转运具有易操作,简便等特点,值得推广使用。 展开更多
关键词 罗丹明123 体外Ussing chamber 回肠 表观渗透系数
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基于Ussing Chamber技术的红景天苷大鼠肠黏膜透过性研究 被引量:5
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作者 顾星 姚少姿 +3 位作者 皮佳鑫 刘博缨 韩煦 刘志东 《天津中医药》 CAS 2016年第11期689-693,共5页
[目的]研究红景天苷在大鼠离体肠黏膜中的透过情况。[方法]采用Ussing Chamber技术,考察不同浓度红景天苷于大鼠肠黏膜透过情况,并考察维拉帕米(Ver)和十二烷基硫酸钠(SDS)对红景天苷大鼠肠黏膜透过的影响。[结果]不同浓度红景天苷在大... [目的]研究红景天苷在大鼠离体肠黏膜中的透过情况。[方法]采用Ussing Chamber技术,考察不同浓度红景天苷于大鼠肠黏膜透过情况,并考察维拉帕米(Ver)和十二烷基硫酸钠(SDS)对红景天苷大鼠肠黏膜透过的影响。[结果]不同浓度红景天苷在大鼠不同肠段的单位时间转运速率(Flux)随浓度升高而增大,不同肠段表观渗透系数(P_(app))无统计学差异(P>0.05)。Ver加入一定量的SDS后,红景天苷在回肠和结肠的P_(app)显著增加(P<0.01或P<0.05),当SDS浓度为2 g/L时,回肠P_(app)增加为对照组的2.76倍。[结论]红景天苷在大鼠全肠段均有吸收,且吸收具有浓度依赖性,以被动吸收为主,Ver对红景天苷大鼠各肠吸收无影响,SDS促进了红景天苷回肠和结肠吸收。 展开更多
关键词 红景天苷 Ussing chamber技术 P-糖蛋白 紧密连接 维拉帕米 十二烷基硫酸钠
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地塞米松磷酸钠脂质体经兔结肠粘膜的体外Ussing chamber渗透研究 被引量:9
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作者 李国锋 陈建海 +4 位作者 杨静 郭丹 任非 王春霞 侯连兵 《第一军医大学学报》 CSCD 北大核心 2004年第1期11-14,共4页
目的观测并评价载药脂质体经结肠粘膜渗透的特点。方法制备地塞米松磷酸钠(DSP)脂质体,采用体外Uss-ing chamber 实验法,考察DSP经时经兔结肠粘膜的累积透过量及在粘膜内的分布量。结果和DSP溶液比较,DSP脂质体能延缓和减少DSP经结肠粘... 目的观测并评价载药脂质体经结肠粘膜渗透的特点。方法制备地塞米松磷酸钠(DSP)脂质体,采用体外Uss-ing chamber 实验法,考察DSP经时经兔结肠粘膜的累积透过量及在粘膜内的分布量。结果和DSP溶液比较,DSP脂质体能延缓和减少DSP经结肠粘膜的透过量。DSP脂质体的表观渗透系数(×10-6,cm/s)为31.95±7.65,和DSP溶液(88.61±18.61)比较,具有显著差异。透过实验120 min和300 min时,DSP脂质体在结肠粘膜中的分布量均明显高于DSP溶液。结论和DSP溶液比较,DSP 脂质体在治疗局部结肠炎时,可能具有更小的毒性,更高的疗效,值得进一步开发研究。 展开更多
关键词 地塞米松磷酸钠 脂质体 结肠粘膜 体外 Ussingchamber渗透 抗炎药
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全边壁条件下CASSON流体在Flow Chamber中流动特性的研究 被引量:5
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作者 樊瑜波 蒋文涛 陈君楷 《生物医学工程学杂志》 EI CAS CSCD 北大核心 1997年第3期293-295,共3页
针对Casson流体在FlowChamber中的流动问题,考虑全边壁条件,用Galerkin有限元方法对流场进行了分析,并将结果与平面应力假设条件下的牛顿流体和Casson流体的情况进行了比较。
关键词 Flow-chamber Casson流体 生物流体力学
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Flow Chamber流动实验中非定常流动特性的研究 被引量:5
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作者 樊瑜波 蒋文涛 陈君楷 《生物医学工程学杂志》 EI CAS CSCD 北大核心 1998年第3期243-245,共3页
利用本征函数法得到了FlowChamber流动实验中非定常流动的速度表达式。它不仅满足任意激励形式下的速度变化过程,而且可以描述速度从初始时刻到任意时刻的变化过程。
关键词 Flowchamber 非定常流动 血液
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Ussing Chamber技术在家禽肠道营养物质转运研究中的应用 被引量:1
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作者 王建国 韩进诚 +1 位作者 王志祥 王筱霏 《中国家禽》 北大核心 2014年第22期43-46,共4页
本文简要介绍Ussing chamber(尤斯灌流)系统的基本构造和原理,总结Ussing chamber技术在家禽肠道营养物质转运中的应用,指出使用过程中可能存在的问题,并探讨解决问题的途径。
关键词 Ussing chamber 肠道 物质转运 家禽
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Assessment of anterior chamber angle changes after phacoemulsification with swept-source OCT 被引量:1
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作者 Qian Zheng Man Hu +2 位作者 Zhang-Liang Li Ping-Jun Chang Yun-E Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第10期1527-1532,共6页
AIM:To assess the changes of anterior chamber angle in patients with shallow anterior chamber after phacoemulsification combined with intraocular lens(IOL)implantation,based on anterior segment swept-source optical co... AIM:To assess the changes of anterior chamber angle in patients with shallow anterior chamber after phacoemulsification combined with intraocular lens(IOL)implantation,based on anterior segment swept-source optical coherence tomography(AS-SS-OCT)measurements.METHODS:This was a prospective case control study;sixty eyes of sixty case were scheduled for cataract surgery with normal intraocular pressure(IOP).Based on anterior chamber depth(ACD)and gonioscopy findings,the eyes were divided into two groups:group of shallow anterior chamber and narrow angle(SAC group,30 eyes);and group of normal anterior chamber group with wide angle(NAC group,30 eyes).Measurements of ACD,anterior chamber volume(ACV),iris volume(IV),lens vault(LV),angle opening distance(AOD),angle recess area(ARA),trabecular iris space area(TISA),and trabecular iris angle(TIA)were conducted in each group before and 3mo after surgery.RESULTS:There was no significant difference in age,axial length(AL),corneal curvature,corneal diameter,intraocular pressure,and IV between two groups before surgery,except for the LV(P=0.000).ACD and ACV were prominently larger in the NAC group than the SAC group 3mo after operation(3.69±0.38 vs 3.85±0.39 mm,P=0.025;161.37±19.47 vs 178.26±20.30 mm3,P=0.002).AOD750,ARA750 in nasal and inferior quadrants,TISA750 in all quadrants except temporal,and TIA750 in all quadrants in SAC group were significantly smaller than those in NAC group after operation(all P<0.05).CONCLUSION:Cataract surgery can deepen anterior chamber and increase the width of anterior chamber angle in Chinese subjects,but the angle related parameters including AOD750,ARA750,TISA750,TIA,TISA750,and ACV in patients with shallow anterior chamber and narrow angle do not reach the normal level. 展开更多
关键词 anterior chamber parameters PHACOEMULSIFICATION shallow anterior chamber anterior segment swept-source optical coherence tomography
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Flow Chamber流动腔高度的数值研究
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作者 张应迁 程春林 《西南民族大学学报(自然科学版)》 CAS 2005年第3期415-417,共3页
平行平板流动腔是当前研究不同切应力下细胞的变形特点的主要工具之一,通过ANSYS计算力学软件,对相同压力边界条件下不同高度的流动腔内的定常不可压粘性流体的流动进行了数值研究,发现FlowChamber流动腔底部切应力只有在离两端有一定... 平行平板流动腔是当前研究不同切应力下细胞的变形特点的主要工具之一,通过ANSYS计算力学软件,对相同压力边界条件下不同高度的流动腔内的定常不可压粘性流体的流动进行了数值研究,发现FlowChamber流动腔底部切应力只有在离两端有一定距离的中间部分才是均匀分布的,而在入口和出口都有比较大的跳跃,入口处的切应力值明显要大于出口处. 展开更多
关键词 FLOW chamber 定常流 切应力
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Measurement of the depths at different regions of the anterior chamber in healthy Chinese adults
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作者 Yuan Zong Qing-Chen Li +3 位作者 Huan Xu Jian Yu Chun-Hui Jiang Xing-Huai Sun 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第1期135-140,共6页
AIM: To measure the depths of different regions of the anterior chamber(AC) in healthy Chinese adults, and to explore possible correlations with age or gender.METHODS: The AC was imaged by swept-source optical coheren... AIM: To measure the depths of different regions of the anterior chamber(AC) in healthy Chinese adults, and to explore possible correlations with age or gender.METHODS: The AC was imaged by swept-source optical coherence tomography in healthy Chinese adults. The horizontal scan of the right eye was used to measure the anterior chamber depth(ACD) at 199 points.RESULTS: A total of 309 images from 309 subjects were analyzed. The ACD values at nearly all locations were negatively correlated with age(all P<0.05), except for ACD1, 2, 198, and 199(correspond to the iris roots). The mean annual decrease 0.013±0.005 mm/y for all ACDs combined, 0.008±0.004 mm/y for the peripheral region, 0.017±0.003 mm/y for the middle peripheral region, and 0.014±0.001 mm/y for the central region. The mean annual decrease was significantly different among these three regions(P<0.001). The ACD was greater in males than in females(P<0.05). The mean difference in ACD between males and females was 0.081±0.025 mm.CONCLUSION: This study showed that optical coherence tomography can be used to measure the ACD of different regions of the AC. We found reductions in ACD with age, although the reduction varied among different points, in healthy Chinese adults. 展开更多
关键词 optical coherence tomography anterior chamber depth age GENDER anterior chamber
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Impacts of ozone on the biomass and yield of rice in open top chambers 被引量:16
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作者 Jin, MB Feng, ZW Zhang, FZ 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第2期233-236,共4页
The impacts of different O 3 concentration on the biomass and yield of rice were studied by using OTC 1 open top chambers. Experimental treatments included the activated charcoal filtered air (CFA), 50 nl/L (CF50), 10... The impacts of different O 3 concentration on the biomass and yield of rice were studied by using OTC 1 open top chambers. Experimental treatments included the activated charcoal filtered air (CFA), 50 nl/L (CF50), 100 nl/L (CF100) and 200 nl/L (CF200) concentrations of O 3. The O 3 treatments significantly decreased the total biomass per plant. The elevated O 3 exposure resulted in a more decrease in the root growth than in the shoot growth. Assessments of yield characteristics at the final harvest revealed an O 3 induced decrease in the number of grains per plant, resulting from fewer ears per plant, fewer grains per ear and more unfilled grains per ear. The 1000 grain dry weight and the harvest index (HI) were not changed significantly under 50 nl/L or 100 nl/L O 3 exposure, but reduced by 17.0% and 4.8% by 200nl/L O 3 treatment, respectively. Compared to the CFA treatment, CF50, CF100 and CF200 treatments caused a 8.2%, 26.1%, 49.1% decrease of the grain yield per plant, and a 14 2%, 31 7%, 51 7% decrease of the total biomass per plant, respectively. Linear regression showed that the 7h-daily mean O 3 concentration exposure for 3 months (July September) and AOT40 (cumulative exposure accumulation over threshold 40 nl/L) were well correlated with the relative grain yield. A yield loss of 10% was estimated to be at 46 9 nl/L O 3 for 7h daily mean O 3 concentration exposure or at 12930 nl/(L·h) O 3 for AOT40. 展开更多
关键词 open TOP chamberS OZONE RICE BIOMASS YIELD
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