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64.
发育期大鼠高热惊厥前后海马γ-氨基丁酸B受体亚基表达的变化 总被引:9,自引:1,他引:8
目的:研究高热惊厥(febrile seizures,FS)对发育期大鼠脑内γ-氨基丁酸(γ-aminobutyric acid,GABA)B受体亚基GABABR1与GABARR2蛋白表达的影响。方法:采用热水浴诱导大鼠高热惊厥模型。隔日诱导惊厥1次,共诱导10次,末次惊厥后24h处死大鼠。发育期大鼠随机分为3组:对照组(n=24),1次高热处理组(n=28),10次高热处理组(n=40)。高热处理组根据是否出现惊厥再分为1次高热惊厥组(FS1,n=16)与1次高热未惊厥组(F1,n=12),10次高热惊厥组(FS10,n=15)与10次高热未惊厥组(F10,n=13)。采用免疫组化方法观察不同次数高热惊厥大鼠脑内GABABR1与GABABR2蛋白表达的变化。结果:FS10大鼠海马齿状回、CAl-CA3区GABABRl和GABABR2蛋白表达明显低于F10、F1、FSl和对照组;F10大鼠上述脑区GABABRl和GABABR2蛋白表达低于F1、FS1和对照组;F1及FS1大鼠与对照组相比差异无显著性;海马各区GABABR1与GABABR2表达的改变大部分平行,但10次高热惊厥后GABABR2在CA1—CA3区下降更明显,而GABABR1在齿状回下降更明显。结论:反复高热惊厥及反复高热均可使发育期大鼠脑内GABABR亚基蛋白表达降低,高热惊厥的影响较单纯高热更为明显,提示GABABR亚单位与发育期大鼠高热惊厥及其脑损伤密切相关。GABABR1与GABABR2改变的不平行可能与受体亚单位组合的可塑性改变有关,这种改变可能导致抑制功能的改变。 相似文献
65.
便携式多普勒血管探测仪在皮瓣移植中的应用 总被引:3,自引:0,他引:3
目的 :研究皮瓣移植前简单、可靠的血管探测的方法。方法 :在皮瓣移植前 ,以 HADECO ES-1 0 0 0 SPM多普勒血管探测仪对皮瓣血管蒂及皮动脉进行探测 ,与术中皮动脉探查结果进行比较 ,考察术前血管探测的准确性和意义。结果 :皮瓣血管蒂及皮动脉术前探测与术中探查结果完全一致。结论 :便携式血管多普勒仪是皮瓣移植前 ,简单、可靠的血管探测的仪器 ,根据探测结果进行皮瓣设计 ,有效地降低了手术失败的风险 相似文献
66.
nm23-H1基因转染对人胆管癌细胞系QBC939体外浸润能力的影响 总被引:1,自引:0,他引:1
目的:探讨nm23-H1基因转染对人胆管癌细胞系QBC939体外浸润能力的影响。方法:将含有全长nm23-H1 cDNA的真核表达载体通过脂腩体法转染人胆管癌细胞系。结果:转染成功的QBC939细胞,其nm23-Hl基因的mRNA、蛋白表达明显增加,转染nm23-H1基因的胆管癌细胞体外浸润能力下降,穿越matrigel的细胞数明显低于亲本QBC939细胞,代表浸润能力的IV型胶原酶(MMP-9)分泌量下降。结论:nm23-Hl基因可以抑制胆管癌细胞的体外浸润能力。 相似文献
67.
A Decade of Change in Obesity Surgery 总被引:4,自引:0,他引:4
Edward E Mason MD PhD Shenghui Tang MS Kathleen E Renquist BS Dwight T Barnes Joseph J Cullen MD Cornelius Doherty MD James W Maher MD 《Obesity surgery》1997,7(3):189-197
Background: The International (formerly National) Bariatric Surgery Registry began collecting data in January 1986. The aim
of this study was to examine changes in the practice of surgical treatment of severe obesity that occurred during the decade
of 1986 through 1995, as observed in the IBSR data. Methods: All data submitted to the IBSR during the decade were transferred
to the IBM mainframe computer for analysis. Characteristics of operative type populations were compared over time using analysis
of variance (ANOVA) for age, body mass index (BMI), operative weight and Chi-square (χ2) test for gender. Results: There has been a steady increase over the decade in mean patient weight. The operations used have
changed from predominantly ‘simple’ operations to more frequent use of ‘complex’ operations. Within the categories of ‘simple’
and ‘complex’, an increase in the variety of operations occurred. As a group, patients with ‘simple’ operations have been
heavier, more often male and public pay patients than those who have undergone ‘complex’ operations. One year weight loss
was greater for Roux-en-Y gastric bypass (RGB) than vertical banded gastroplasty (VBG), but follow-up rates were too low to
study the relative merits of the operations used. The reported incidence of operative mortality and serious complications
(leak with peritonitis, abscess and pulmonary embolism) remained low. Conclusions: These observations and their implications
can be summarized in three statements which relate to action for improved patient care in the beginning of the new century:
(1) increasing weight of candidates for surgical treatment during this decade indicates the need for earlier use of operative
treatment before irreversible complications of obesity can develop; (2) low risk of obesity surgery, decreasing postoperative
hospital stay, and early weight control support the continued and increased use of surgical treatment; (3) continued widespread
use of both ‘simple’ and ‘complex’ operations with increased modifications of standard RGB and VBG procedures emphasizes the
need for standardized long-term data and analyses regarding both weight control and postoperative side-effects. 相似文献
68.
86对母婴血清标本用间接酶联免疫测定法(ELISA)测定了乙型脑炎抗体,118对用血凝抑制(血抑)试验测定了麻疹抗体。结果发现,脐血乙型脑炎抗体阳性率为79.1%,母血为74.4%,几何平均滴度在脐血显著高于母血(t=5.1857,P<0.01),比值为1.2∶1。脐血和母血的麻疹血抑抗体阳性率分别为86.4%及84.8%,几何均值也是前者高于后者(t=4.0349,P<0.01),比值为1.3∶1。 108份婴儿血清标本测定结果显示,0~3个月婴儿乙型脑炎抗体阳性率为35%,4~9个月仅为13%,10个月及以上的婴儿全部阴性。此结果与近年上海市小于1岁组乙型脑炎发病率最高相一致,提示应考虑提早乙型脑炎疫苗的接种年龄。 相似文献
69.
111例双黄连过敏反应文献分析 总被引:9,自引:0,他引:9
目的:分析临床应用双黄连引致的过敏反应的规律。方法:对2000年1月-2004年3月中国期刊网中收录的111例双黄连过敏反应在性别、年龄、发生时间、给药途径和临床表现进行分析。结果:双黄连过敏与年龄、性别无关,与给药途径有关,注射剂易发生过敏反应。该药过敏的临床表现有:过敏性休克67例(60%),皮肤黏膜症状61例(55%),其他类型过敏反应14例(13%)31例同时出现多种过敏症状。过敏发生时间最短为开始用药1m in以内,最长为用药后72h,97例(87%)在用药过程中发生过敏症状。结论:双黄连的过敏反应以速发型过敏反应(如过敏性休克)为主,应是临床关注的重点。 相似文献
70.
Tiziano Curti MD Gianandrea Pasquinelli MD Paola Preda BS Antonio Freyrie MD Renzo Laschi MD Massimo D’Addato MD 《Annals of vascular surgery》1989,3(4):351-363
Human adult endothelial cells were enzymatically harvested from adipose tissue. Cell viability was established by Trypan blue exclusion and transmission and scanning electron microscopy. Endothelial cells were identified by immunocytochemical investigation at light microscopy, transmission electron microscopy, and scanning electron microscopy. Isolated cells were positive for actin and vimentin, negative for desmin. Factor VIII RA was mainly expressed at cell surface and occasionally disclosed in the cytoplasm. Reactivity for UEA I and J15 was weak or undetectable. Human endothelial cells were seeded and left to adhere for one hour onto different nonvascular substrates (glass, poly-l-lysine, formvar-carbon, fibronectin, Teflon). Scanning electron microscopy defined surface features, suggesting tenacious cell adhesion on the substrate. Different vascular substrates were tested (preclotted Dacron, albumin Dacron, Hemashield Dacron, Gelseal Dacron, ePTFE, fibronectin-ePTFE). Commercially available coated grafts showed qualitative and quantitative differences in cell adhesion. In particular, Gelseal Dacron provided the best quantitative results, even though a wide variability was observed. In contrast, fibronectin-coated ePTFE gave more reliable results and high spreading efficiency. In the short term, coated grafts do not seem to offer greater advantages than fibronectin-coated ePTFE. However, specific incubation times for each coated graft should be selected and the long-term approach (graft culture) should also be attempted. 相似文献