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991.
R M Fujitani  J L Mills  L M Wang  S M Taylor 《Journal of vascular surgery》1992,16(3):459-67; discussion 467-8
To determine the influence of unilateral internal carotid arterial occlusion (ICO) on Doppler frequency spectral analysis (DFSA) of the patent contralateral carotid artery, a retrospective review of 154 patients between July 1987 and December 1991 with angiographically confirmed ICO was performed, correlating duplex and arteriographic findings in a blinded fashion. Biplane arteriograms and bilateral carotid artery duplex studies that used a 5.0 MHz Doppler probe with a 1.5 mm3 sample volume at a 60 degree angle of insonation were performed on all patients. Each carotid artery was categorized by the severity of stenosis as quantified by arteriography: 1% to 15% (n = 41); 16% to 49% (n = 48), 50% to 79% (n = 21), 80% to 99% (n = 34), and bilateral occlusion (n = 10). DFSA peak systolic frequencies were commonly exaggerated in the presence of contralateral ICO and use of standard criteria for DFSA interpretation overestimated bifurcation stenoses in 43 of 89 lesions (48.3%) when determining nonhemodynamically significant lesions (less than 50% diameter reduction) with a sensitivity of only 57.3% and specificity of 96.9%. Conversely, prediction of hemodynamically significant lesions (greater than 50% diameter reduction) with standard criteria had 96.9% sensitivity but only 57.3% specificity. Modification of these criteria to account for the velocity increase or "jet effect" in the ipsilateral carotid artery system increased the sensitivity and specificity to 97.8% in predicting nonhemodynamically and hemodynamically significant stenoses respectively. A Doppler frequency spectrum with a peak systolic frequency (PSF) greater than 4.0 kHz and end-diastolic frequency (EDF) less than 5 kHz with an "open window" distinguished lesions with less than 50% diameter reduction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
992.
雪旺氏细胞(Schwann cell,SC)在神经再生过程中起着重要作用。我们取人胚及兔之坐骨神经,采用“植块多次移出法”培养出纯净度达99%的人和兔的SC。对培养的SC进行了冻存和复苏处理,复苏后的细胞可保持原有的生长特性。  相似文献   
993.
We previously reported the discovery of 14 channels in the human body, which possessed the biophysical property of high emission of light. In this study we found the same property on the Ren and Du channels in healthy rats. Additionally, we discovered that the luminance of the related channels in rat models with different "syndromes" varied greatly. For instance, a markedly low luminance appeared on the Du channel in animals with experimental syndrome of Yang deficiency induced by hydrocortisone; while in animals with experimental syndrome of blood deficiency caused by bleeding, an apparently low luminance occurred on the Ren channel. The intensity of the emitted light on Du and Ren channels increased after acupuncture treatment, but not significantly. This phenomenon conforms to the theory in traditional Chinese medicine that the Du channel is the "sea of Yang channels", while the Ren channel is the "sea of Yin channels".  相似文献   
994.
995.
雷公藤对雄性大鼠脑垂体前叶黄体生成细胞的影响   总被引:1,自引:1,他引:0  
利用抗β-黄体生成素(β-LH)单克隆抗体,采用免疫组织化学方法,并结合电镜超微结构,观察雷公藤总甙(GTW)和单体T_4对雄性大鼠脑垂体前叶黄体生成细胞(LH细胞)的影响。结果表明,LH细胞出现一些形态改变。随着雷公藤剂量的增加,LH细胞胞浆内免疫酶反应增强,胞浆内出现空泡。超微结构也显示,LH细胞胞核皱缩,胞浆内高尔基复合体和内质网肿胀,在总甙组和T_4大剂量组,LH细胞类似“阉割细胞”样变。提示雷公藤的抗生育作用类似去性腺效应.  相似文献   
996.
运用单向混合淋巴细胞培养的方法分别检测了10例习惯性流产史船娠夫妇间、流产史孕妇和无关第三者(男性)间及9例正常妊娠夫妇间的HLA-D抗原的相容性。结果发现流产史夫妇间的HLA-D抗原相容性大于流产史孕妇和无关第三者(男性)之间及正常夫妇间的HLA-D抗原相容性(P<0.01)。提示夫妇间的HLA-D抗原相容性增大可能是导致习惯性流产的原因之一。同时,在反应体系中分别加入不同孕妇血浆以观察其对单向混合淋巴细胞培养(单向MLC)的影响时发现,流产史孕妇血浆对单向MLC不仅无抑制作用,反而有刺激作用,而正常孕妇血浆对单向MLC有抑制作用。推测正常孕妇血浆中存在特异和/或非特异的封闭因子,而流产史孕妇血浆中缺乏特异和/或非特异的封闭因子。  相似文献   
997.
Binding properties and localization of [3H]ohmefentanyl, a new ligand for mu opioid receptors, were investigated on normal human brain sections. Binding assays performed at the level of the basal ganglia revealed: (1) a steady-state binding reached after 60 min incubation at room temperature, (2) the presence, in saturation experiments, of an apparent single class of binding sites with a Kd = 1.68 +/- 0.45 nM and a Bmax = 162 +/- 9 fmol/mg protein, (3) an order of potency to inhibit [3H]ohmefentanyl binding as follows: ohmefentanyl greater than [D-Ala2, MePhe4, Gly-ol5] enkephalin (DAGO) greater than ethylketocyclazocine (EKC) much greater than Tyr-D-Ser(OtBu)-Gly-Phe-Leu-Thr(OtBu) (BUBU) and U-50,488H. Quantitative autoradiography showed an heterogeneous distribution of [3H]ohmefentanyl binding sites with the highest densities in amygdala, medical geniculate body, thalamus, and caudate nucleus. Binding characteristics and anatomical distribution also show that [3H]ohmefentanyl may bind to a small proportion of additional sites called "DAGO-inaccessible [3H]ohmefentanyl specific binding sites." [3H]Ohmefentanyl binding to these sites can be partly inhibited by sigma ligands such as 1,3-di-o-tolylguanidine (DTG) and haloperidol. However, unlabeled DAGO inhibited more than 80% of [3H]ohmefentanyl specific binding in most of the human brain regions studied, suggesting that the major population of sites labeled by [3H]ohmefentanyl represented mu opioid receptors.  相似文献   
998.
999.
报告14例大疱性表皮坏死松解型药疹的治疗。以磺胺类药和解热镇痛药引起者居多,各4例。皮损面积按九分法计算,皮损面积80%以上者9例,80%以上者5例,治愈9例,死亡5例,我们认为早期使用足够剂量皮质激素类药物是有效措施。病程中注意防治感染,给予足够的液体以防止水电解质失平衡,局部治疗使用本院中药“五黄油”。  相似文献   
1000.
According to our supposition that "humoral mechanism" plays an important role in the pathogenesis of portal hypertension due to cirrhosis, antagonists to some of humoral substances would lower the portal pressure in cirrhotic patients. Wedged hepatic venous pressure (WHVP) was used as an indicator for changes of portal pressure. Cimetidine was given intravenously to 8 cirrhotic patients, in whom an average lowering of 0.72 kPa (7.3 cm H2O) of WHVP was observed subsequently. This change was of clinical significance as compared with the previous results of splenorenal shunting operations.
  相似文献   
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