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81.
Measurement of γ-enolase release, a new method for selective quantification of neurotoxicity independently from glial lysis 总被引:4,自引:0,他引:4
We have developed a sensitive enzymatic-immunoassay to quantify the level of gamma-enolase (a specific neuronal enzyme) which is released from cultured cells after exposure to various toxins. We show that this method can estimate selectively neuronal cell death without significantly interfering with glial cell death. Indeed, no gamma-enolase is released when glial cells are killed with free-radical producing agents. Experiments comparing the levels of neuronal cell death induced by NMDA or free-radical producing drugs, performed either by measuring gamma-enolase release or using the classical fluorescein diacetate method, yielded similar results. In addition to selectively follow neuronal death in a mixed population of neurons and glial cells, this method provides a way of determining the cell death kinetics from a single culture dish, since enolase can be measured on small samples taken from the culture medium. Finally, we propose these two methods as being complementary and useful neuronal and other cellular death indexes and also to understand the complex problem of glial influence on neuronal survival or death. 相似文献
82.
永瓣藤化学成分的研究 总被引:2,自引:1,他引:1
永瓣藤化学成分的研究陈玲,谢平,戚薇,曾菊珍(药学系中药化学教研室)关键词永瓣藤,化学成分,三萜,蒜盘子甾酮永瓣藤(MonimopetalnmChinenseRe-hd)系卫矛科永瓣藤属植物[1],为我国特有的珍稀二类保护植物[2],分布于江西东北部... 相似文献
83.
84.
Objective To investigate the role of inflammatory cytokines in the pathogenesis of chronic non-bacterial prostatitis/chronic pelvic pain syndrome (CAP/CPPS) patients. Methods The 38 cases with CAP/CPPS patients (18 cases of CAP and 20 cases of CPPS) and 20 cases of healthy controls were selected. The differential expressions of 40 kinds of inflammatory cytokines were detec-ted by antibody arrays in prostate fluid. Results The inflammatory cytokines which increased more than 1.5 times expression have been found. There were seven kinds in CAP including monocyte che-moattractant protein (MCP)-1, solution tumor necrosis factor receptor Ⅱ(s TNF R Ⅱ), platelet-de-rived growth faetor-BB (PDGF-BB), interleukin (IL)-β, IL-11、IL-6、MCP-2 and five kinds in CPPS groups including MCP-1、PDGF-BB、MCP-2、s TNF R Ⅱ、It-11 respectively, compared with healthy control group. The cluster analysis results showed that protein expression of Monocyte chemoattrac-tant protein 1 (MCP-1)and platelet-derived growth factor BB (PDGF-BB) were significantly increased in CAP (3.47 and 2.07 times) and CPPS (2.25 and 2.19 times) compared with healthy control group and were the final polymerization of inflammatory cytokines. The protein expression of interleukin 1 β (IL-1 β), MCP-1 and soluble tumor necrosis factor Ⅱ (s TNF R Ⅱ) in CAP group was increased more than 1.85,1.55,1.67 times compared with CPPS group. Conclusions Elevated expression of inflammatory cytokines may play an important role in the course of CAP/CPPS disease. The extent of the inflammatory response of CAP was higher than CPPS. The inflammatory factors of MCP-1 and PDGF-BB could serve as a novel diagnostic marker. 相似文献
85.
长、短链探针以链延伸反应提高基因传感器检测MRSA灵敏度的实验研究 总被引:16,自引:8,他引:8
目的:利用链延伸反应的原理延长引物链以提高石英谐振式基因传感器表面的质量负载,从而提高传感器检测MRSA的灵敏度。方法:以不对称PCR的反应产物做为长链探针,人工合成的寡核苷酸片段为短链探针,在基因传感器阵列表面分别固定上金黄色葡萄球菌mecA和femA的长链及短链探针共4种探针片段,与相应的靶序列杂交后,加入Klenow酶,37℃进行链延伸反应1h。结果:长、短链探针均有效地固定了传感器表面。mecA,femA短链探针在链延伸反应前的检测灵敏度为0.5nmol/L,但经链延伸反应后检测灵敏提高到了0.05nmol/L;而长链探针却无法与相应的基因组靶序列发生杂交。结论:短链探针链延伸反应有效地提高了石英谐振式基因传感器的灵敏度,但该法不适用于链探针。 相似文献
86.
目的 探讨肝脏移植后的免疫损伤与几种主要分子伴侣(热休克蛋白)表达状况之间的内在规律。方法 34份移植后肝脏穿刺标本和10份正常肝脏标本,分为A(无排斥反应)组、B(轻/中度急性排斥反应)组、C(重度急性排斥反应)组、D(慢性排斥反应/肝纤维化)组、E(对照)组。进行HSP60、HSP70、HSP90、HO—1等四种分子伴侣免疫组织化学分析和图像分析。结果 B和C组各指标间无统计学差异,A、D、E与B、C组间有统计学差异。HSP60在移植肝脏中表达降低,排斥反应发生时高;HSP70和HSP90在移植肝脏中升高。HO—1肝脏移植后升高。结论 不同种类的热休克蛋白依据自身表达的特点对移植后的免疫损伤作出反应,体现了细胞的自我保护机制。 相似文献
87.
内毒素血症时大鼠脂多糖结合蛋白的变化及其意义 总被引:2,自引:0,他引:2
目的 探讨内毒素血症时大鼠肝组织中脂多糖结合蛋白mRNA的表达、血浆中脂多糖结合蛋白 (LBP)含量的变化及其意义。方法 经大鼠尾静脉注入内毒素 (5mg/kg)建立内毒素血症动物模型 ,检测不同时点模型鼠肝组织中LBPmRNA的表达 ,同时检测血浆中LBP、内毒素、TNF α及IL 6含量的变化 ,并与对照组相比较。另取肝组织在电镜下观察其病理学改变。结果 随着内毒素血症时间的延长 ,内毒素组大鼠肝组织LBPmRNA的表达明显增强 ,血浆中LBP、TNF α和IL 6含量也明显增加 ,与对照组比较差异有高度显著性 (P<0 .0 1)。电镜观察见肝细胞脂肪变 ,线粒体空化 ,枯否氏细胞数量增多、体积增大、吞噬功能增强。结论 内毒素血症时 ,大鼠肝组织中LBPmRNA表达明显增强 ,血浆中LBP含量也明显增加。由此提示 ,增高的LBP可能在脂多糖介导的枯否氏细胞激活及产生、释放各种炎性介质中可能起了重要作用。 相似文献
88.
The Effects of Na~+/Ca~(2+) exchange (NCX) on the Repolarization of Canine Ventricular Myocyte-Potential Arrhythmogenic Effect of NCX during a Mis-matched Repolarization and Relaxation Xiamen Zhongshan Hospital, Xiamen Medical College, Xiamen University@巩燕$Visiting scholar of cardiac arrhythmia research institute,university hospital of Oklahoma!U.S.A
@王焱
@BELA Szabo$Basic cardiac research laboratory,cardiac arrhythmia research institute,university hospital of Oklahoma!… 相似文献
89.
我国古典精品小说《三言》,是明代冯梦龙编纂的《喻世明言》、《警世通言》、《醒世恒言》的总称。其内容揭露达官贵人的穷奢极欲的腐朽生活,歌颂男女青年纯真的爱情,语言诙谐讽刺,有较高的文学价值。书中还有涉及中医中药的情节,现撷析如下。《警世通言》第17回“钝秀才一朝交泰”有黄胜因嫖妓而患广疮及医治的情节:黄胜“终日穿花街,过柳巷,在院子里婊子家行乐。常言道‘乐极生悲’,嫖出一身广疮……将白金百两送太医,只求速愈。太医用轻粉劫药,数日之内,身体光鲜……不勾半年,疮毒大发,医治不痊,呜呼哀哉死了。”[1]太医用轻粉治广疮(即… 相似文献
90.
Management of chronic lunotriquetral ligament tears 总被引:1,自引:0,他引:1
Treatment of chronic disruptions of the lunotriquetral (LT) ligament is not well-defined. Eleven patients treated by LT fusion with use of a compression screw are reported. The injury frequently resulted from hyperextension of the wrist. Pain on the ulnar side of the wrist, limited motion, and tenderness over the LT joint exacerbated by ballottement were present. Standard radiographs were normal. Arthrography showed the ligamentous tear in all cases. After operation, immobilization was continued until fusion was apparent radiographically. Fusion was achieved in all cases between 2 and 5 months. Four patients were free of pain, four patients had pain only at the extremes of motion, and three patients had persistent pain. Mean wrist motion was as follows (preoperative/postoperative): flexion (53 degrees/45 degrees), extension (60 degrees/49 degrees), radial deviation (17 degrees/21 degrees), and ulnar deviation (25 degrees/18 degrees). Maximum grip strength as a percentage of the uninjured side was 73% preoperatively and 59% postoperatively. LT tears can exist de novo or as part of the ulnar impaction syndrome; a method for differentiation is presented. 相似文献