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991.
常规染色体畸变分析法对AT细胞高辐射敏感性的研究   总被引:2,自引:0,他引:2  
目的 研究毛细血管扩张性共济失调症(ataxia-telangiectasia,AT)患者皮肤的成纤维细胞系AT5BIVA(AT细胞)的高辐射敏感性。方法 以源于正常人皮肤的成纤维细胞系GM0639(GM细胞)为对照,用常规染色体畸变分析法,在AT细胞和GM细咆经60COγ射线0、1、2、3、4 Gy照射后,观察比较AT细胞和GM细胞之间染色体畸变率(CAF)的差异,并分别进行曲线拟合。结果 在0、1、2、3、4 Gy剂量下,AT细胞染色体畸变率明显高于GM细胞(P<0.05);AT和GM细胞染色体畸变率与剂量成正相关,均可拟合成剂量效应直线方程Y=a+bX,且AT细胞剂量效应直线回归方程斜率明显大于GM细胞(P<0.05)。结论 AT患者AT细胞的辐射敏感性显著高于GM细胞,具有高辐射敏感性。  相似文献   
992.
益气化瘀法治疗糖尿病皮肤溃疡38例临床观察   总被引:10,自引:6,他引:4  
糖尿病皮肤溃疡是外科常见病、多发病,因其反复发作,长期不愈,形成顽固性难愈性溃疡,愈后又极易复发,少数尚有癌变可能,所以严重影响了患者的身心健康及生命质量。西医多集中在控制血糖、抗感染、外用生长因子、外科清创术及植皮术等治疗措施上,虽然有一定的疗效,但是却缺乏安全有效加速创面愈合的积极措施。我们采用益气化瘀法为主治疗糖尿病溃疡,可以明显促进与加速创面愈合,减少疤痕形成,提高愈合质量。1993年10月~2002年12月共收治38例糖尿病皮肤溃疡患者,取得了较好的疗效。现报道如下。  相似文献   
993.
对SARS抗体动态水平的系统观察   总被引:2,自引:1,他引:1  
目的应用化学发光光度分析法对SARS抗体(SARS-Ab)动态水平进行观察.方法对432例SARS病人在恢复期的不同阶段进行检测.结果显示SARS病人的抗体检出率为94.0%(404/432).病人SARS-Ab在2,3,4周和2个月时,抗体检出平均光子数值为3.79,7.71,12.31和24.17;3~8个月SARS-Ab下降率分别为92.9%,83.3%,40.0%,26.7%,13.3%和7.0%.结论病人在患病初期,SARS-Ab呈上升趋势,3个月后逐渐下降,并能动态观察不同年龄组SARS-Ab的明显差异.  相似文献   
994.
Objective:To investigate the relationship between antibiotic administration and the changes in bacteriological profile in a burn unit. Methods: The data of consumption of different kinds of antibiotics, including total antibiotic consumption [expressed as the number of defined daily doses (DDD)] as well as pathogen identification, were collected in a 8-year period. The constituent ratios of different kinds of antibiotics in total antibiotic consumption to isolation rates of various species of bacteria were calculated, and their correlation was analyzed. Results: Within this period, it was found that the aminoglycosides and first generation cephalosporins were used less frequently, while the polypeptides, carbopenem and macrolides were used proportionally more. At the same time, the isolation rates of Staphylococcus aureus, Acinetobacter sp, Enterobacter cloacae, Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus were gradually increased. The constituent ratios of predominant pathogens were correlated to the different kinds of antibiotics consumption in the burn unit. Conclusion: The results suggested that the consumption of different antibiotics was closely related to the trends of emergence of bacterial isolates from infected burn wounds. The result might imply that to regulate the administration of certain antibiotics might help decrease the emergence of certain pathogenic bacteria in burn infections.  相似文献   
995.
996.
血管紧张素Ⅱ作为肾素-血管紧张素系统的主要活性肽,根据其与肽类和非肽类的选择性亲和力可分为两个亚型,分别命名为AT1-R和AT2-R。AT1-R可被特异的非肽类拮抗剂所阻断,如沙坦类;AT2-R拮抗剂包括非肽类化合物PD 123317和PD 123319,还有一部分AT2-R的配体是肽类激动剂,如CGP 4221等,这些肽类配体在炎症过程中也可以和非血管紧张素位点结合〔1〕。AT1-R在调节心血管效应、体液和电解质的平衡、激素释放和饮水行为方面的作用已被确认,部分AT1-R拮抗剂已经用于高血压的治疗,而AT2-R的生理功能尚不清楚。1 AT2-R的结构AT2-R分子结…  相似文献   
997.
目的 探讨计算机体层成像多平面重建(CTMPR)在评价椎间融合中的作用,寻找定量评价椎间融合的新方法.方法 13例行腰椎间融合的患者术后1周、3个月、6个月行CTMPR,行椎间融合器(Cage)内植骨CT值定量测量.结果 术后1周Cage内植骨CT值为(619.52±26.97)Hu,术后3个月为(628.69±42.60)Hu,术后6个月为(657.77±37.43)Hu.术后1周与术后3个月相比无显著性差异,与术后6个月相比有显著性差异.结论 CT值的测量在椎间融合的判断中具有高准确性.  相似文献   
998.
目的研究Wnt信号中β-catenin基因第3外显子突变及蛋白异常表达在胰腺实性-假乳头状瘤(SPTs)发生中的作用。方法①对15例SPTs石蜡包埋组织进行DNA提取,PCR扩增,PCR产物纯化、测序,对β-catenin基因第3外显子进行突变分析。②采用免疫组化PV6000法检测SPTs组织中β-catenin蛋白的表达。结果①β-catenin基因第3外显子在15例SPTs组织中有12例发生了一个碱基的错义突变,突变率为80.0%,表现在密码子32位(5例)、33位(3例)和37位(4例)。②15例SPTs组织中有13例β-catenin蛋白呈细胞核表达,异常表达率为86.7%。结论Wnt信号中β-catenin基因突变及蛋白核内聚集在SPTs发生中起重要作用。  相似文献   
999.
Objective To investgate the effects of TGF β 3 on rat hepatic fibrosis. Methods The TGF β 3 cDNA was cloned into rAAV2 vector. Rats were randomly divided into four groups: normal control group, model group, negative control group and TGF β 3 group. Hepatic fibrosis was induced by hypodermic injection of 40% CCI4. Recombinant AAV2-TGF β 3 viral particles were injected via the vena caudalis one week before CCh treatment. Rats were executed 8 weeks after CCI4 treatment, global histological change was observed after HE staining, the distribution of the collagen fibers was observed after masson staining, his-tochemistry was done to observe the expression of collagen Ⅰ; The positive area rate of the collagen fibers and the average optical rate of collagen Ⅰ were quantified. Results HE staining indicated that collagen fibers were reduced in the TGF β 3 group. Masson staining shown that the collagen fibers were distributed around the blood vessel, in the portal area and disse space. Compared to the model group (13.2%±2.2%) and negative control group (12.3%±1.5%), the collagen fibers in liver tissues of TGF β3 group (7.7% ± 1.5%) were significantly decreased (q = 9.456, P < 0.01; q = 8.217, P < 0.01). Histochemistry indicated that the collagen fibers of liver tissues of TGF 15 3 group (0.185±0.033) were significantly higher than those in the model group (0.252±0.042) and the negative control group (0.230±0.029), (q = 6.228, P < 0.01; q = 4.346, P < 0.01). Conclusion TGF β 3 alleviates the damage to hepatic cell and the level offibrosis in CCI4 treated rats and inhibits the expression of collagen Ⅰ.  相似文献   
1000.
BACKGROUND: Preservation of hair follicle units for the purpose of delayed transplant will help us graft thousands of hair grafts at one session, even in a clinic with fewer assistants and less equipment. OBJECTIVE: This study was undertaken to evaluate and compare the viability of hair follicle units preserved at 0 and 4 degrees C for various periods. MATERIALS AND METHODS: Cell cultures and transplant of hair follicle units into athymic mice were performed. RESULTS: Outer root sheath cells could be cultivated in 96% (0 degrees C group) and 92% (4 degrees C group) of the hair follicles after 24 hours of preservation, whereas 85% (0 degrees C group) and 79% (4 degrees C group) of the follicles implanted into the mice regrew well after the same period of preservation. Then, in both the 0 degrees C and the 4 degrees C group, these rates decreased significantly with length of preservation in cell cultures and mice transplant; however, 0 degrees C seems better than 4 degrees C for preservation of grafts (p<.05). CONCLUSION: Grafts are better preserved at 0 degrees C instead of 4 degrees C. When delayed transplant is an option, it should be completed within 24 hours and no later than 48 hours.  相似文献   
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