AIM: To investigate which surgical techniques and perioperative regimens yielded the best survival rates for diabetic rats undergoing gastric bypass. METHODS: We performed Roux-en-Y gastric bypass with reserved gastri...AIM: To investigate which surgical techniques and perioperative regimens yielded the best survival rates for diabetic rats undergoing gastric bypass. METHODS: We performed Roux-en-Y gastric bypass with reserved gastric volume, a procedure in which gastrointestinal continuity was reestablished while excluding the entire duodenum and proximal jejunal loop. We observed the procedural success rate, long-term survival, and histopathological sequelae associated with a number of technical modifications. These included: use of anatomical markers to precisely identify Treitz's ligament; careful dissection along surgical planes; careful attention to the choice of regional transection sites; reconstruction using full-thickness anastomoses; use of a minimally invasive procedure with prohemostatic pretreatment and hemorrhage control; prevention of hypo-thermic damage; reduction in the length of the procedure; and accelerated surgical recovery using fast-track surgical modalities such as perioperative permissive underfeeding and goal-directed volume therapy. RESULTS: The series of modif ications we adopted reduced operation time from 110.02 ± 12.34 min to 78.39 ± 7.26 min (P < 0.01), and the procedural success rate increased from 43.3% (13/30) to 90% (18/20) (P < 0.01), with a long-term survival of 83.3% (15/18) (P < 0.01). CONCLUSION: Using a number of fast-track and damage control surgical techniques, we have successfully established a stable model of gastric bypass in diabetic rats.展开更多
Background and Objective Large randomized controlled trials have demonstrated that percutaneous coronary intervention （PCI） with the routine use of drug-eluting stents is safe and effective, however, the patients ol...Background and Objective Large randomized controlled trials have demonstrated that percutaneous coronary intervention （PCI） with the routine use of drug-eluting stents is safe and effective, however, the patients older than 75 years undergoing PCI are at increased risk for major adverse cardiac events, so that the patients are usually excluded from this trial. The aim of the present study was to assess the early clinical outcome and risk factors in old patients with acute ST elevation myocardial infarction （STEMI） following primary PCI. Methods We analyzed the outcome after stenting in 136 patients older than 60 years in our coronary care unit with acute STEMI, and the patients were further classified in 2 age groups： patients≥75 years and 〈75 years. Results Though the older group had a higher prevalence of adverse baseline characteristics and lower final TIMI flow than those of the younger, the procedural success had no difference between two groups. The main adverse clinical events （MACE） for the old group was a little higher comparing with the younger in 12-month following up. Conclusions Our study suggest that drug-eluting stent implantation in elderly patients with acute ST elevation myocardial infarction has high initial procedural success rates despite having more severe baseline risk characteristics, and to shorten the time form symptom onset to PCI and improve final TIMI flow strategy may decrease MACE among old patients following PCI（J Geriatr Cardio12009; 6：67-70）.展开更多
Objective: The aim of the present study was to assess the early clinical outcome and risk factors in old patients with acute ST elevation myocardial infarction (STEMI) following primary percutaneous coronary intervent...Objective: The aim of the present study was to assess the early clinical outcome and risk factors in old patients with acute ST elevation myocardial infarction (STEMI) following primary percutaneous coronary intervention (PCI). Methods: A total of 136 patients older than 60 years with STEMI who received successful PCI were included in this study. The patients were classified in 2 age groups: patients ≥75 years and <75 years of age. The extent of coronary artery lesions was measured by quantitative coronary artery angiography (QCA). Subjects were tracked for subsequent cardiovascular events: cardiac death, myocardial infarction, heart failure, percutaneous coronary intervention, coronary artery bypass and stroke. Results: Though the older group had a higher prevalence of adverse baseline characteristics and lower final TIMI flow than patients<75y (P<0.05), the procedural success did not make difference between the two groups. In 12 months follow-up of 136 study participants, there occurred 39 CV events : cardiac death (five patients), heart failure (nineteen patients), and stroke (six patients). Three patients received coronary bypass grafts and six patients underwent PCI. Heart failure and overall cardiovascular event rates were higher in older patients compared with those in patients<75y. The main adverse clinical events (MACE) for the old group were a little higher comparing with the younger in 12-month follow-up (P=0.029 6 and P=0.043 4). Multivariate cox analysis identified that a diagnosis of diabetes (HR 2.495, 95%CI 1.224 to 5.083, P= 0.011 8) and time from symptom(HR 1.450, 95%CI 1.143 to 1.841, P= 0.008 2) to PCI as independent predictors of CV events after adjustment of all entered baseline variables. Conclusion: Our study suggests that drug-eluting stent implantation in older patients with acute ST elevation myocardial infarction has high initial procedural success rates despite having more severe baseline risk characteristics, and to shorten the time from symptom onset to PCI may decrease cardiovascular events in old patients following PCI.展开更多
Objective The purpose of this study was to compare remote magnetic catheter navigation with manual navigation for the ablation of atrioventricular nodal reentry tachycardia （AVNRT）. Methods From November 2007 to Nov...Objective The purpose of this study was to compare remote magnetic catheter navigation with manual navigation for the ablation of atrioventricular nodal reentry tachycardia （AVNRT）. Methods From November 2007 to November 2009, 30 consecutive patients with AVNRT received radiofrequency ablation in the Institute of Geriatric Cardiology. Of them, 14 were treated with remote magnetic navigation （RMN） and 16 with manual catheter navigation （MCN）. Total fluoroscopic time,procedure time, procedural success rate, and complication rate were compared between the two groups. Results Total fluoroscopy time and precise orientation time were reduced in RMN group compared to MCN group （7.5＋0.3 min vs 13.9~5.3 rain, and 1.0-x-0.3 min vs 3.2：~0.6 min, respectively, both P〈0.05）. Procedural success rates in both groups were 100% and no AVNRT recurred in all patients during 3 months＇ follow-up. The number of lesions delivered was less for RMN group （3.4~1.1 vs 6.3＋2.2, P〈0.05）. Total procedure time （25.6~7.5 rain vs 27.5a：6.2 rain,/〉〉0.05） was similar between the 2 groups. No procedural complications occurred in both groups. Conclusions RMN for mapping and ablation of AVNRT significantly reduce precise orientation time, total fluoroscopy time and number of lesions delivered compared to the conventional technique of manual steering of deflectable catheters. Remote magnetic control mapping and ablation of AVNRT is more safe and feasible （J Geriatr Cardio12010; 7：7-9）.展开更多
Boiling structures on evaporation surface of red copper sheet with a diameter （D） of 10 mm and a wall thickness （h） of 1 mm were processed by the ploughing-extrusion （P-E） processing method, which is one part of...Boiling structures on evaporation surface of red copper sheet with a diameter （D） of 10 mm and a wall thickness （h） of 1 mm were processed by the ploughing-extrusion （P-E） processing method, which is one part of the phase-change heat sink for high power （HP） light emitting diode （LED）. The experimental results show that two different structures of rectangular- and triangular-shaped micro-grooves are formed in P-E process. When P-E depth （ap）, interval of helical grooves （dp） and rotation speed （n） are 0.12 ram, 0.2 mm and 100 r/min, respectively, the boiling structures of triangular-shaped grooves with the fin height of 0.15 mm that has good evaporation performance are obtained. The shapes of the boiling structures are restricted by dp and ap, and dp is determined by n and amount of feed （f）. The ploughing speed has an important influence on the formation of groove structure in P-E process.展开更多
Broadband phase shifters are mostly proposed and fabricated based on the scheme proposed by Shiffman, which uses a coupled line with far ends connected together and a uniform transmission line to give a differential p...Broadband phase shifters are mostly proposed and fabricated based on the scheme proposed by Shiffman, which uses a coupled line with far ends connected together and a uniform transmission line to give a differential phase shift. Based on the unique dispersion property of the composite right/left-handed (CRLH) metamaterial structure, a new configuration is presented in this paper for fabricating the broadband differential phase shifter, which employs a novel CRLH metamaterial structure as one of the differential phase-shift arms, instead of the conventional coupled line. The new circuit can achieve a phase shift of 90° in an operational bandwidth as broad as one octave and its phase deviations are quite small. An original design of the novel broadband phase shifter is presented, in which the artificial CRLH structure was implemented by microstrip quasi-lumped elements. Both the simulated and measured results of the 90° broadband differential phase shifter are presented.展开更多
基金Supported by Scientific Research Fund of Heilongjiang Provincial Education Department, No. 11541200Harbin Medical University First Affi liated Hospital, No. 2007098
文摘AIM: To investigate which surgical techniques and perioperative regimens yielded the best survival rates for diabetic rats undergoing gastric bypass. METHODS: We performed Roux-en-Y gastric bypass with reserved gastric volume, a procedure in which gastrointestinal continuity was reestablished while excluding the entire duodenum and proximal jejunal loop. We observed the procedural success rate, long-term survival, and histopathological sequelae associated with a number of technical modifications. These included: use of anatomical markers to precisely identify Treitz's ligament; careful dissection along surgical planes; careful attention to the choice of regional transection sites; reconstruction using full-thickness anastomoses; use of a minimally invasive procedure with prohemostatic pretreatment and hemorrhage control; prevention of hypo-thermic damage; reduction in the length of the procedure; and accelerated surgical recovery using fast-track surgical modalities such as perioperative permissive underfeeding and goal-directed volume therapy. RESULTS: The series of modif ications we adopted reduced operation time from 110.02 ± 12.34 min to 78.39 ± 7.26 min (P < 0.01), and the procedural success rate increased from 43.3% (13/30) to 90% (18/20) (P < 0.01), with a long-term survival of 83.3% (15/18) (P < 0.01). CONCLUSION: Using a number of fast-track and damage control surgical techniques, we have successfully established a stable model of gastric bypass in diabetic rats.
文摘Background and Objective Large randomized controlled trials have demonstrated that percutaneous coronary intervention （PCI） with the routine use of drug-eluting stents is safe and effective, however, the patients older than 75 years undergoing PCI are at increased risk for major adverse cardiac events, so that the patients are usually excluded from this trial. The aim of the present study was to assess the early clinical outcome and risk factors in old patients with acute ST elevation myocardial infarction （STEMI） following primary PCI. Methods We analyzed the outcome after stenting in 136 patients older than 60 years in our coronary care unit with acute STEMI, and the patients were further classified in 2 age groups： patients≥75 years and 〈75 years. Results Though the older group had a higher prevalence of adverse baseline characteristics and lower final TIMI flow than those of the younger, the procedural success had no difference between two groups. The main adverse clinical events （MACE） for the old group was a little higher comparing with the younger in 12-month following up. Conclusions Our study suggest that drug-eluting stent implantation in elderly patients with acute ST elevation myocardial infarction has high initial procedural success rates despite having more severe baseline risk characteristics, and to shorten the time form symptom onset to PCI and improve final TIMI flow strategy may decrease MACE among old patients following PCI（J Geriatr Cardio12009; 6：67-70）.
文摘Objective: The aim of the present study was to assess the early clinical outcome and risk factors in old patients with acute ST elevation myocardial infarction (STEMI) following primary percutaneous coronary intervention (PCI). Methods: A total of 136 patients older than 60 years with STEMI who received successful PCI were included in this study. The patients were classified in 2 age groups: patients ≥75 years and <75 years of age. The extent of coronary artery lesions was measured by quantitative coronary artery angiography (QCA). Subjects were tracked for subsequent cardiovascular events: cardiac death, myocardial infarction, heart failure, percutaneous coronary intervention, coronary artery bypass and stroke. Results: Though the older group had a higher prevalence of adverse baseline characteristics and lower final TIMI flow than patients<75y (P<0.05), the procedural success did not make difference between the two groups. In 12 months follow-up of 136 study participants, there occurred 39 CV events : cardiac death (five patients), heart failure (nineteen patients), and stroke (six patients). Three patients received coronary bypass grafts and six patients underwent PCI. Heart failure and overall cardiovascular event rates were higher in older patients compared with those in patients<75y. The main adverse clinical events (MACE) for the old group were a little higher comparing with the younger in 12-month follow-up (P=0.029 6 and P=0.043 4). Multivariate cox analysis identified that a diagnosis of diabetes (HR 2.495, 95%CI 1.224 to 5.083, P= 0.011 8) and time from symptom(HR 1.450, 95%CI 1.143 to 1.841, P= 0.008 2) to PCI as independent predictors of CV events after adjustment of all entered baseline variables. Conclusion: Our study suggests that drug-eluting stent implantation in older patients with acute ST elevation myocardial infarction has high initial procedural success rates despite having more severe baseline risk characteristics, and to shorten the time from symptom onset to PCI may decrease cardiovascular events in old patients following PCI.
文摘Objective The purpose of this study was to compare remote magnetic catheter navigation with manual navigation for the ablation of atrioventricular nodal reentry tachycardia （AVNRT）. Methods From November 2007 to November 2009, 30 consecutive patients with AVNRT received radiofrequency ablation in the Institute of Geriatric Cardiology. Of them, 14 were treated with remote magnetic navigation （RMN） and 16 with manual catheter navigation （MCN）. Total fluoroscopic time,procedure time, procedural success rate, and complication rate were compared between the two groups. Results Total fluoroscopy time and precise orientation time were reduced in RMN group compared to MCN group （7.5＋0.3 min vs 13.9~5.3 rain, and 1.0-x-0.3 min vs 3.2：~0.6 min, respectively, both P〈0.05）. Procedural success rates in both groups were 100% and no AVNRT recurred in all patients during 3 months＇ follow-up. The number of lesions delivered was less for RMN group （3.4~1.1 vs 6.3＋2.2, P〈0.05）. Total procedure time （25.6~7.5 rain vs 27.5a：6.2 rain,/〉〉0.05） was similar between the 2 groups. No procedural complications occurred in both groups. Conclusions RMN for mapping and ablation of AVNRT significantly reduce precise orientation time, total fluoroscopy time and number of lesions delivered compared to the conventional technique of manual steering of deflectable catheters. Remote magnetic control mapping and ablation of AVNRT is more safe and feasible （J Geriatr Cardio12010; 7：7-9）.
基金Projects(50436010, 50675070) supported by the National Natural Science Foundation of China Project(07118064) supported by the Natural Science Foundation of Guangdong Province, China+1 种基金 Project(U0834002) supported by the Joint Fund of NSFC-Guangdong of ChinaProjects(SY200806300289A, JSA200903190981A) supported by Shenzhen Scientific Program, China
文摘Boiling structures on evaporation surface of red copper sheet with a diameter （D） of 10 mm and a wall thickness （h） of 1 mm were processed by the ploughing-extrusion （P-E） processing method, which is one part of the phase-change heat sink for high power （HP） light emitting diode （LED）. The experimental results show that two different structures of rectangular- and triangular-shaped micro-grooves are formed in P-E process. When P-E depth （ap）, interval of helical grooves （dp） and rotation speed （n） are 0.12 ram, 0.2 mm and 100 r/min, respectively, the boiling structures of triangular-shaped grooves with the fin height of 0.15 mm that has good evaporation performance are obtained. The shapes of the boiling structures are restricted by dp and ap, and dp is determined by n and amount of feed （f）. The ploughing speed has an important influence on the formation of groove structure in P-E process.
基金Project supported by the National Basic Research Program (973) of China (No. 2004CB719802)the National Natural Science Founda-tion of China (No. 60378037)the Science and Technology Department of Zhejiang Province, China (No. 2005C31004)
文摘Broadband phase shifters are mostly proposed and fabricated based on the scheme proposed by Shiffman, which uses a coupled line with far ends connected together and a uniform transmission line to give a differential phase shift. Based on the unique dispersion property of the composite right/left-handed (CRLH) metamaterial structure, a new configuration is presented in this paper for fabricating the broadband differential phase shifter, which employs a novel CRLH metamaterial structure as one of the differential phase-shift arms, instead of the conventional coupled line. The new circuit can achieve a phase shift of 90° in an operational bandwidth as broad as one octave and its phase deviations are quite small. An original design of the novel broadband phase shifter is presented, in which the artificial CRLH structure was implemented by microstrip quasi-lumped elements. Both the simulated and measured results of the 90° broadband differential phase shifter are presented.
