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1.
上肢骨干天鹅型记忆接骨器的设计与临床应用   总被引:85,自引:10,他引:75  
目的:研究应用于上肢骨干骨折与骨不连内固定的新型记忆合金接骨器。方法:利用镍钛合金与上肢骨干解剖生理的特性和特征,采用光弹,电测及三维有限元法研制天鹅型记忆接骨器(SMC),临床应用于锁骨、肱骨、尺桡骨干骨折与骨不连188例243根,平均随访2.25年。结果:SMC在轴向多点位抗剪、折、旋、持骨力98.40-125.05N;在纵向,将152-196N的记忆应力作用于骨断端。骨不连92例106例,平均术后3.8个月,不连处为类骨板样骨替代,骨折93例134根,平均术后2.6个月骨折处为骨板样愈合,全部病例无感染,无取出本器后再骨折和因本器所致的关节功能障碍,优良率98.76%,结论:SMC多点位轴向持骨,纵向加压、是治疗上肢骨干骨折与骨不连新而有效的技术与方法。  相似文献
2.
苦参碱对SMMC-7721细胞系的诱导分化作用   总被引:82,自引:2,他引:80  
张燕军  夏天  赵建斌 《医学争鸣》1998,19(3):340-343
目的:研究苦参碱对人肝癌细胞系SMMC-7721的诱导分化作用.方法:用细胞培养方法,观察细胞增殖、形态、功能和代谢等方面指标,研究苦参碱(Ma)对人肝癌细胞系SMMC-7721在体外的诱导分化作用.结果:各处理组细胞均出现细胞增殖抑制,亚细胞结构趋于正常,AFP分泌量明显低于培养天数相同的对照组细胞,γ-GT活力逐日下降,酪氨酸-α-酮戊二酸转移酶(TAT)活力始终高于对照组细胞.处理6d后,细胞DNA含量降低,S期细胞数增加.结论:Ma可使SMMC-7721细胞聚集于S期,诱导其向正常肝细胞分化  相似文献
3.
硫化氢作为心血管信号分子的研究   总被引:67,自引:10,他引:57  
To explore the possibility of hydrogen sulfide (H 2S) as a messenger molecule in cardiovascular system, the authors discovered that H 2S (5×10 -5 -5×10 -4 mol·L -1 )exerted an effect on inhibiting endothelin 1 induced proliferation of cultured vascular smooth muscle cells (VSMCs) of rats in vitro . The 3H TdR incorporation decreased by 16.8%~37.4% in H 2S treated VSMCs as compared with the controls ( P <0.01). The inhibitory effect was found to be associated with reduced activity of MAPK. The authors also observed that endogenous H 2S levels markedly increased in vessels of rats with either endotoxic shock or septic shock [H 2S level (pmol·min -1 ·mg -1 ):tail artery (16.18±2.06) vs (8.12±0.55);mesenteric artery (10.17±1.11) vs (6.19 ±0.55);pulmonary artery(11.38±1.24) vs (5.27±0.51); aorta(6.21±0.48) vs (4.10± 0.28), P < 0.01 ]. The above findings suggested that H 2S might play an important role in the regulation of cardiovascular pathophysiologic events.  相似文献
4.
我国戊型肝炎研究   总被引:65,自引:0,他引:65  
戊型肝炎既往被称为肠道传播的非甲非乙型肝炎.1989 年 Reyes 等[1]应用分子克隆技术获得本病毒的基因克隆,并正式将此型肝炎及其相关病毒分别命名为戊型肝炎( hepatitis E ) 和戊型肝炎病毒( hepatitis E virus, HEV ).  相似文献
5.
Background The infarct size determines the long-term prognosis of patients with acute myocardial infarction (AMI). There is a growing interest in repairing scar area by transplanting bone marrow stem cells. However, effectiveness of intracoronary injection of bone marrow mesenchymal stem cells (BMSCs) in patients with AMI still remains unclear.Methods Sixty-nine patients with AMI after percutaneous coronary intervention (PCI) were randomly divided into intracoronary injection of BMSCs (n=34) and saline (control group, n=35) groups. Serial single positron emission computer tomography (SPECT), cardiac echo and cardiac electromechanical mapping were done at the designed time intervals until six months after transplantation of BMSCs or injection of saline. Results The proportion with functional defect decreased significantly in the BMSCs patients after three months [(13±5)%] compared with that pre-transplantation [(32±11)%] and the control group [(28±10)%] at three month follow-up (P&lt;0.05, respectively). Wall movement velocity over the infracted region increased significantly in the BMSCs group [(4.2±2.5) cm/s vs (2.2±1.3) cm/s, P&lt;0.05], but not in the control group [(2.2±1.5) cm/s vs (2.7±1.7) cm/s, P&gt;0.05]. Left ventricular ejection fraction (LVEF) three months after transplantation in BMSCs group increased significantly compared with that pre-implantation and with that of the control group at three months post-injection [(67±11)% vs (49±9)% and (53±8)%, P&lt;0.05 respectively]. SPECT scan results showed that perfusion defect was improved significantly in BMSCs group at three-month follow-up compared with that in the control group [(134±66)cm2 vs (185±87)cm2, P&lt;0.01]. At the same time, left ventricular end-diastolic volume [(136±31) ml vs (162±27) ml, P&lt;0.05] and end-systolic volume [(63±20) ml vs (88±19) ml, P&lt;0.05] decreased synchronously. The ratio of end-systolic pressure to end-systolic volume [Psyst/ESV, (2.84±1.30) mmHg/ml vs (1.72±1.23) mmHg/ml, P&lt;0.05] increased significantly. Cardiac electromechnical mapping demonstrated significant improvement at three months after implantation of BMSCs compared with that pre-injection in both cardiac mechanical capability as left line local shorting [LLS, (11.29±1.64)% vs (7.32±1.86)%, P&lt;0.05] and electrical property as left ventricular endocardial unipolar voltage [UV, (10.38±1.12) mV vs (7.61±1.09) mV, P&lt;0.01]; perfusion defect decreased from (36.2±6.2) % to (20.3±5.31)% (P&lt;0.01). Twenty-four-hour electrocardiographic monitoring demonstrated no arrhythmias occurred at three-months follow-up.Conclusions The transplantation of BMSCs might improve the cardiac function and it is safe and feasible with no deaths or malignant arrhythmias.  相似文献
6.
高血压研究四十年   总被引:54,自引:0,他引:54  
为探讨我国高血压的发病情况,研究高血压的防治和发病机制,中国医学科学院阜外医院高血压研究室与流行病学研究室,基础医学研究所生理学系及药物研究所药理学研究室自1959年始陆续开展了全国高血压流行病学调查和人群防治试点、高血压治疗研究、高血压发病机制研究和中药降压作用研究。研究结果表明:(1)我国高血压的患病率逐年增高,自1959年的5.11%,上升至1979年的7.73%和1991年的11.26%。但患者的知晓率仅26.3%,治疗率仅12.1%,控制率仅2.8%。体重超重和经常饮酒是我国高血压的危险因素,高钠、低钾、低钙及低蛋白饮食是血压升高的因素。我国人群中血压升高是冠心病和脑卒中发病的最重要危险因素。(2)建立了我国高血压诊断和分期标准。发现在我国高血压患者中继发性高血压仅占1.1%。率先提出了大动脉炎的概念并发现大动脉炎是肾性高血压的主要原因。对患者进行身心教育调动其主观能动性,加以低剂量的复方降压制剂有效地促进了群防群治工作的开展。大样本多中心随机对照临床实验证实,对高血压性脑卒中和心肌梗死的治疗可明显降低其再发和死亡危险。(3)对实验性高血压大鼠阻力动脉平滑肌收缩机制研究证明,血管平滑肌细胞Ca2 转运、利用、代谢及其调控因素均发生一系列变化,并具有遗传因素,这是血液循环外周  相似文献
7.
考马斯亮蓝微盘比色法测定蛋白质含量   总被引:50,自引:5,他引:45  
目的 建立快速、灵敏的测定蛋白质的方法。方法 以考马斯亮蓝作为显色剂,用酶联免疫测定仪微盘比色测定牛血清白蛋白和小鼠肝组织匀浆的蛋白含量,并与常量比色法进行了比较,结果 考马斯亮蓝微盘比色法与常量法相比,对样品的测定结果相近,而前者样品用量少(只需几微升),简便、快速、检测极限低(0.63ug)。结论 考马斯亮蓝微盘比色法是一种简单、快速、灵敏的蛋白质测定方法,尤其适用于大批量、微量样品的蛋白质含量测定。  相似文献
8.
Context  Prior intravascular ultrasound (IVUS) trials have demonstrated slowing or halting of atherosclerosis progression with statin therapy but have not shown convincing evidence of regression using percent atheroma volume (PAV), the most rigorous IVUS measure of disease progression and regression. Objective  To assess whether very intensive statin therapy could regress coronary atherosclerosis as determined by IVUS imaging. Design and Setting  Prospective, open-label blinded end-points trial (A Study to Evaluate the Effect of Rosuvastatin on Intravascular Ultrasound-Derived Coronary Atheroma Burden [ASTEROID]) was performed at 53 community and tertiary care centers in the United States, Canada, Europe, and Australia. A motorized IVUS pullback was used to assess coronary atheroma burden at baseline and after 24 months of treatment. Each pair of baseline and follow-up IVUS assessments was analyzed in a blinded fashion. Patients  Between November 2002 and October 2003, 507 patients had a baseline IVUS examination and received at least 1 dose of study drug. After 24 months, 349 patients had evaluable serial IVUS examinations. Intervention  All patients received intensive statin therapy with rosuvastatin, 40 mg/d. Main Outcome Measures  Two primary efficacy parameters were prespecified: the change in PAV and the change in nominal atheroma volume in the 10-mm subsegment with the greatest disease severity at baseline. A secondary efficacy variable, change in normalized total atheroma volume for the entire artery, was also prespecified. Results  The mean (SD) baseline low-density lipoprotein cholesterol (LDL-C) level of 130.4 (34.3) mg/dL declined to 60.8 (20.0) mg/dL, a mean reduction of 53.2% (P<.001). Mean (SD) high-density lipoprotein cholesterol (HDL-C) level at baseline was 43.1 (11.1) mg/dL, increasing to 49.0 (12.6) mg/dL, an increase of 14.7% (P<.001). The mean (SD) change in PAV for the entire vessel was –0.98% (3.15%), with a median of –0.79% (97.5% CI, –1.21% to –0.53%) (P<.001 vs baseline). The mean (SD) change in atheroma volume in the most diseased 10-mm subsegment was –6.1 (10.1) mm3, with a median of –5.6 mm3 (97.5% CI, –6.8 to –4.0 mm3) (P<.001 vs baseline). Change in total atheroma volume showed a 6.8% median reduction; with a mean (SD) reduction of –14.7 (25.7) mm3, with a median of –12.5 mm3 (95% CI, –15.1 to –10.5 mm3) (P<.001 vs baseline). Adverse events were infrequent and similar to other statin trials. Conclusions  Very high-intensity statin therapy using rosuvastatin 40 mg/d achieved an average LDL-C of 60.8 mg/dL and increased HDL-C by 14.7%, resulting in significant regression of atherosclerosis for all 3 prespecified IVUS measures of disease burden. Treatment to LDL-C levels below currently accepted guidelines, when accompanied by significant HDL-C increases, can regress atherosclerosis in coronary disease patients. Further studies are needed to determine the effect of the observed changes on clinical outcome. Trial Registration  ClinicalTrials.gov Identifier: NCT00240318   相似文献
9.
丹参酮ⅡA对大鼠局灶性脑缺血再灌注损伤的保护作用   总被引:47,自引:1,他引:46  
目的:观察丹参酮ⅡA对大鼠局灶性脑缺血再灌注损伤的保护作用.方法:采用线栓法制备大鼠局灶性脑缺血再灌注模型,以水溶性的丹参酮ⅡA纳米制剂灌胃给药,观测其对脑缺血大鼠的神经行为、脑梗塞范围和脑含水量以及脑组织SOD活力、MDA含量和NO水平的影响.结果:丹参酮ⅡA(25 mg/kg)能使脑缺血大鼠的神经行为明显改善,脑梗塞范围和脑含水量显著降低;丹参酮ⅡA亦能拮抗脑缺血再灌注引起的SOD活力的下降及MDA含量的升高,并使脑组织NO水平显著下降.结论:丹参酮ⅡA对大鼠局灶性脑缺血再灌注损伤具有很好的保护作用.  相似文献
10.
Preoperative radiotherapy for resectable rectal cancer: A meta-analysis   总被引:46,自引:0,他引:46  
CONTEXT: The benefit of adjuvant radiotherapy for resectable rectal cancer has been extensively studied, but data on survival are still equivocal despite a reduction in the rate of local recurrence. OBJECTIVE: To assess the effectiveness of preoperative radiotherapy followed by surgery in the reduction of overall and cancer-related mortality and in the prevention of local recurrence and distant metastases. DATA SOURCES: Computerized bibliographic searches of MEDLINE and CANCERLIT (1970 to December 1999), including non-English sources, were supplemented with hand searches of reference lists. The medical subject headings used were rectal cancer, radiotherapy, surgery, RCT, randomized, and clinical trial. STUDY SELECTION: Studies were included if they were randomized controlled trials (RCTs) comparing preoperative radiotherapy plus surgery with surgery alone and if they included patients with resectable histologically proven rectal adenocarcinoma, without metastatic disease. Fourteen RCTs were analyzed. DATA EXTRACTION: Data on population, intervention, and outcomes were extracted from each RCT according to the intention-to-treat method by 3 independent observers and combined using the DerSimonian and Laird method. DATA SYNTHESIS: Radiotherapy plus surgery compared with surgery alone significantly reduced the 5-year overall mortality rate (odds ratio [OR] 0.84; 95% confidence interval [CI], 0.72-0.98; P =.03), cancer-related mortality rate (OR, 0.71; 95% CI, 0.61-0.82; P<.001), and local recurrence rate (OR, 0.49; 95% CI, 0.38-0.62; P<.001). No reduction was observed in the occurrence of distant metastases (OR, 0.93; 95% CI, 0.73-1.18; P =.54). CONCLUSIONS: In patients with resectable rectal cancer, preoperative radiotherapy significantly improved overall and cancer-specific survival compared with surgery alone. The magnitude of the benefit is relatively small and criteria are needed to identify patients most likely to benefit from adjuvant radiotherapy. JAMA. 2000;284:1008-1015  相似文献
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