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81.
报告手术证实小脑萎缩110例,主要CT表现为小脑半球及(或)蚓部脑沟增多,增宽及不同程度第四脑室、桥前池、桥小脑角池、环池及小脑上池扩大。建议采用后颅窝薄层扫描以减少或避免后颅窝伪影干扰。提出小脑半球或蚓部脑沟在2条以上,小脑半球脑沟宽度超过1mm,蚓部脑沟宽度超过2mm,并有相应的小脑症状及体征,即可诊为小脑萎缩。还讨论了小脑萎缩的原因及其CT表现。  相似文献   
82.
胆管癌相关抗原(CCRA)是我们从人胆管癌组织中提取的一种新的肿瘤标志物。建立了检测CCRA的ELISA方法,检测了40例正常人及268例良恶性疾病病人血清的CCRA浓度,后者包括胆管癌36例、原发性肝癌40例、胰腺癌26例、胃癌31例、结直肠癌34例、肺癌17例、肝硬变20例、胆石症40例及胃溃疡24例。结果显示:40例正常对照组的血清CCRA浓度为(14.38±7.34)μg/ml(x±s),正常上限为28.95μg/ml(x+2s);血清CCRA诊断胆管癌的敏感性是77.78%,明显高于其它肿瘤组(0~25)%(P<0.001),特异性是(75~100)%。认为对于胆管癌的诊断,CCRA可能是一种较特异的肿瘤相关抗原。  相似文献   
83.
对127例IgA肾病(IgAN)患者和25例非IgA系膜增殖性肾炎血清进行了抗内皮细胞抗体AECA的检测。结果表明:IgA肾病患者和非IgA系膜增殖性肾炎患者血清AECA-IgG较正常对照组高,而IgAN患者较非IgA系膜增殖性肾炎患者AECA-IgG的水平高,P〈0.05。IgAN患者的AECA-IgA水平较正常对照组高。IgAN患者按AECA水平分为阳性与阴性组,对两组硬化面积比进行比较,未见  相似文献   
84.
几种植物来源不同作用机制的抗癌药抗侵袭作用   总被引:4,自引:0,他引:4  
用细胞培养法和癌细胞侵袭实验,观察几种植物来源不同作用机理的抗癌药如紫杉醇、三尖杉酯碱、高三尖杉酯碱及喜树碱[1],对黑色素瘤高转移株B16-BL6细胞及人纤维肉瘤细胞HT-1080的细胞毒作用和抗侵袭作用。结果表明紫杉醇、三尖杉酯碱、高三尖杉酯碱及喜树碱对B16-BL6和HT-1080细胞增殖均有很强的抑制作用。紫杉醇、三尖杉酯碱及高三尖杉酯碱对B16-BL6细胞侵袭和运动也有明显的抑制作用,而喜树碱在同样浓度下对B16-BL6细胞侵袭和运动均无明显抑制。  相似文献   
85.
Z X Han 《中华外科杂志》1989,27(9):546-9, 574
From 1975 to 1987, 965 exudate cultures of burn wounds were done in 553 cases. 1205 colonies (28 species) of microorganisms were separated out from these patients. Among 1205 colonies, 1050 colonies (87.13%) were "common microorganism" included P. aeruginosa, E. coli, S. aureus, and P. vulgaris. There were mixed infection of P. aeruginosa and E. coli in 23.66-25.95% cases. In early stage P. aeruginosa (23.25%) was predominant and in late stage, S. aureus was predominant. The sensitivity of microorganisms to 18 kinds of antibiotics gradually decreased, year by year. The authors consider that reasonable use of antibiotics, early eschar excision and skin grafting play an important role in decreasing the occurrence of drug-fast bacteria and preventing cross infection.  相似文献   
86.
药根碱对肾上腺素alpha受体的阻断作用及部分激动作用   总被引:3,自引:0,他引:3  
  相似文献   
87.
C X Xu  R Han 《中国药理学报》1989,10(6):546-560
The proliferation of L 1210 cells ceased rapidly after they were exposed to homoharringtonine (HH) 1 microgram/ml during exponential growth phase. However, 25.3% of the cells were still able to form colonies in soft agar if HH was removed after 24 h of incubation (the colony-forming efficiency for control cells was 62.5%). The clonogenic cells survived from the treatment were still sensitive to HH-continuous exposure. The IC50 of the treated and control cells were 15 and 20 ng/ml, respectively. Yet, the sensitivity of the treated cells to cytarabine decreased enormously. For instance, the survival rate of HH-treated cells remained at 100% level after they were exposed to cytarabine 4-8 micrograms/ml for 1 h, but only 40% control cells survived from the same treatment. When cells were continuously exposed to HH 0.4 micrograms/ml, the colony-forming efficiency decreased exponentially as a function of exposure time. The T1/2 of the clonogenic cells was about 18 h. The DNA contents in L 1210 cells was measured with a flow-cytometer. The results showed that the cell-cycle progress in all cells was interrupted by HH, regardless which phase they belonged to. So the cells seemed to be in a "frozen" state and the histogram unchanged.  相似文献   
88.
89.
While attempting to find a suitable crosslinking reagent for biopolymers, a naturally occurring proanthocyanidin (PA) obtained from grape seeds was selected to fix biological tissues. The cytotoxicity and crosslinking rate, reflected by the in vitro and in vivo degradation of fixed matrices has been studied. The shrinkage temperature of the fixed bovine pericardium increased from 66 to 86 degrees C. A cytotoxicity assay using fibroblast cultures revealed that PA is approximately 120 times less toxic than glutaraldehyde (GA), a currently used tissue stabilizer. In vitro degradation studies showed that fixed tissue was resistant to digestion by bacterial collagenase. Crosslinks between PA and tissues can be stabilized by decreasing the dielectric constant of the solution during storage. After subcutaneous implantation for periods ranging between 3 and 6 weeks, we found no apparent degradation of the GA- or PA-fixed tissues, whereas fresh tissue controls rapidly disintegrated. Beyond 6 weeks PA crosslinks began to degrade. More fibroblasts migrated and proliferated inside the PA-fixed implants compared with GA counterparts. Tissues crosslinked with PA manifested an enhanced collagen expression and deposition and did not calcify after implantation. GA, on the other hand, even after thorough rinsing continued to be cytotoxic, inhibited collagen synthesis and encouraged dystrophic calcification. Collagen matrices crosslinked with PA are expected to be of value in the design of matrices that will encourage cell ingrowth and proliferation, which are temporary in nature, and that are intended to regenerate or replace missing tissues, which can delay the biogradation of collagen. As such they should be of significant value in the emerging field of tissue engineering.  相似文献   
90.
用精子头部银染法观察几种雄性抗生育因子的作用   总被引:1,自引:0,他引:1  
叶惟三  邓艳春 《解剖学报》1992,23(3):290-293
  相似文献   
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