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91.
目的:研制皮肤发疱仪,并临床应用于自体表皮移植治疗白癜风,分析治疗效果。方法:根据局部皮肤双控发疱理论,应用负反馈原理,研制出皮肤双控发疱仪;该仪器应用于自体表皮移植治疗白癜风,通过控制局部发疱部位的压力和温度,实现发疱时需要的恒压和恒温。结果:皮肤发疱仪能恒定控制局部皮肤发疱时的压力和温度,使自体表皮移植治疗白癜风的总成活率达到98.01%。结论:皮肤发疱仪性能稳定,操作方便,临床应用效果好,值得推广。 相似文献
92.
为比较盐酸二甲双胍和糖适平对Ⅱ型糖尿病的治疗效果,通过33例Ⅱ型糖尿病患者服用二甲双胍和35例Ⅱ型糖尿病患者服用糖适平,观察4mo后发现二甲双胍在降低血糖、24h尿糖定量,降低血脂及逆转外周神经病变方面有显著疗效。但二甲双胍不能升高血浆C—肽水平,不能降低24h尿蛋白质定量。如能将二甲双胍和糖适平联合应用将会提高疗效,减轻副作用。 相似文献
93.
In 1985, previously unknown outbreaks of smallpox were uncovered which had occurred in Shanxi Province and Nei Monggol Autonomous Region in northern China during 1962-1965, several years after smallpox transmission was thought to have been interrupted. During field investigation, the authors learned that most of the cases were known to local health officials but had not been officially reported to national authorities. All were among persons who had been variolated or were their close contacts. Variolation is an ancient method of protection against naturally acquired smallpox that was officially proscribed in the early 1950s but was renewed in remote areas when smallpox vaccination activities were interrupted during the three-year famine of 1959-1962, following the "great leap forward" program of 1958. It was found that the variolators in Shanxi Province and Nei Monggol Autonomous Region inoculated persons with the use of powdered smallpox scabs mixed with human milk, and that they obtained fresh supplies of scabs every 6-12 months by variolating relatives and friends. The health authorities responded by capturing the variolators, confiscating their variolation material and equipment, and vaccinating the population. The last known cases occurred in 1965, and the practice of variolation is now believed to be extinct. 相似文献
94.
目的 探讨颈动脉管、颈静脉窝与下鼓室的变异关系 ,为此区域手术提供可靠的解剖学资料。方法 在XSQ~Ⅱ型手术显微镜下解剖观察了 2 0 0例颞骨标本的下鼓室 ,并用游标卡尺对有关结构进行了测量。结果 下鼓室纵径 0 2 8mm ,横径为 0 85mm ,深为 1 2 8mm。下鼓室底与颈静脉窝相毗邻者见 93 0 %。当颈静脉窝大而上隆时 ,窝顶与鼓室间以薄骨板分隔 ,骨板最薄时仅为 0 2 0mm。颈静脉窝顶突入鼓室腔者占 1 2 5 % ,窝顶有骨质缺损者见 4 0 %。鼓室底与颈动脉管关系随颈动脉位置变化而异 ,有 6 8 0 %的标本颈动脉管位于岬下缘前 1 / 3区 ,4 0 %的标本颈动脉管占据范围达岬下缘后 1 / 3区。结论 下鼓室与颈静脉窝及颈动脉管存在着多种变异关系 ,下鼓室手术及静脉窝区手术应避免损伤颈静脉球及颈内动脉等结构 相似文献
95.
将人白细胞介素2(hIL-2)cDNA克隆到逆转录病毒载体MNSM的PL位点 ,分别构建了转录受SV40早期启动子和人甲胎蛋白增强子调控的重组逆转录病毒载体MNSI和MNSIA。用脂质体转染法将MNSI和MNSIA分别转导PA317包装细胞,测质粒转染率为(5~20)×10~(-3)克隆/μgDNA·10~6细胞,病毒感染率为(5.4~450)×10~4CFU/ml。重组病毒在4μg/ml polybrene存在条件下感染人肝癌细胞、肾癌细胞和黑色素瘤细胞,Neo~R克隆经Southernblot分析证明hIL-2cDNA转入人肿瘤细胞并整合, R NA斑点杂交及IL-2活性表达分析证明,人甲胎蛋白增强子可促进异源启动子启动hIL-2cD-NA在合成甲胎蛋白的人肝癌细胞中高效特异转录和表达。该研究对肝癌特异性免疫增强基因治疗有重要意义。 相似文献
96.
Two putative cDNAs of acetylcholinesterase (AChE), one from Dermacentor variabilis, and the other from Rhipicephalus sanguineus, were amplified and sequenced. The deduced amino acid sequences have high amino acid identities (between 70 and 94%) to known tick AChE sequences deposited in GenBank. Furthermore, these two AChEs also possess common features in their primary AChE structure such as catalytic active sites. A 2,220-bp contiguous sequence, containing a 1,791-bp open reading frame encoding an AChE precursor with 596 amino acid residues, was obtained from D. variabilis. The deduced proteins of R. sanguineus are different in size by 6 amino acids because of alternative splicing at the 5' end. A gene tree deduced from phylogenetic analysis indicates that there are at least three lineages of AChE in arthropods. 相似文献
97.
Inhibition of platelet adherence to brain microvasculature protects against severe Plasmodium berghei malaria
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Sun G Chang WL Li J Berney SM Kimpel D van der Heyde HC 《Infection and immunity》2003,71(11):6553-6561
Some patients with Plasmodium falciparum infections develop cerebral malaria, acute respiratory distress, and shock and ultimately die even though drug therapy has eliminated the parasite from the blood, suggesting that a systemic inflammatory response contributes to malarial pathogenesis. Plasmodium berghei-infected mice are a well-recognized model of severe malaria (experimental severe malaria [ESM]), and infected mice exhibit a systemic inflammatory response. Because platelets are proposed to contribute to ESM and other systemic inflammatory responses, we determined whether platelet adherence contributes to experimental malarial pathogenesis. Indeed, a significant (P < 0.005) increase in the number of rolling and adherent platelets was observed by intravital microscopy in brain venules of P. berghei-infected mice compared with the number in uninfected controls. P-selectin- or ICAM-1-deficient mice exhibit increased survival after P. berghei infection. We observed a significant (P < 0.0001) reduction in the morbidity of mice injected with anti-CD41 (alpha(IIb) or gpIIb) monoclonal antibody on day 1 of P. berghei infection compared with the morbidity of infected controls injected with rat immunoglobulin G. Additionally, platelet rolling and adhesion in brain venules were reduced in P. berghei mice lacking either P-selectin or ICAM-1 or when the platelets were coated with anti-CD41 monoclonal antibody. Unlike other inflammatory conditions, we did not detect platelet-leukocyte interactions during P. berghei malaria. Because (i). leukocyte adhesion is not markedly altered in the absence of P-selectin or ICAM-1 and (ii). CD41 is not an adhesion molecule for parasitized erythrocytes, these findings support the hypothesis that inhibition of platelet adhesion to the brain microvasculature protects against development of malarial pathogenesis. 相似文献
98.
目的检测广东地区正常人群和鼻咽癌患者中细胞色素P450酶系CYP2F1基因的多态性,并分析该基因遗传多态性与鼻咽癌易感性的关联。方法采用直接测序法检测40例鼻咽癌患者全血标本中CYP2F1基因全部10个外显子的多态性变化。对于等位基因频率较高的多态性位点,进一步采用错配聚合酶链反应.限制性片段长度多态性检测368例鼻咽癌患者和344名正常对照人群中该位点的等位基因频率。结果在40例鼻咽癌样本中,共检测到CYP2F1基因的35个单核苷酸多态性。其中,10个单核甘酸引起编码的氨基酸改变,1个移码突变,15~16bp之间插入C引起移码突变(15-16ins C),该等位基因频率为25%。但病例-对照分析却未能显示该位点突变与鼻咽癌易感的相关性(P〉0.05)。结论中国广东人的CYP2F1基因遗传多态性位点较多,但暂未发现与鼻咽癌的易感性关联的单一多态位点,多个多态性位点或不同基因多态性位点的协同互补作用可能才是鼻咽癌发生发展的关键影响因素。 相似文献
99.
健脾补肾药对脾虚大鼠细胞因子水平的影响 总被引:18,自引:3,他引:18
目的 :观察健脾补肾方药对实验性脾虚证大鼠细胞因子的影响 ,探讨脾虚证与细胞因子的关系及脏腑相关的意义。方法 :选用SD雄性大鼠 ,随机分为 :正常对照组 ,脾虚模型组 ,健脾补肾方高、低剂量组 ,通过大黄复制脾虚证动物模型 ,并用健脾补肾方药进行防治。采用放射免疫分析观察各组动物血清肿瘤坏死因子(TNF)、白细胞介素 - 6 (IL - 6 )、白细胞介素 - 2 (IL - 2 )水平的变化。结果 :脾虚模型组大鼠血清TNF、IL - 6、IL - 2含量均比正常对照组显著降低 (p <0 0 1) ,而健脾补肾方药能明显升高TNF、IL - 6、IL - 2含量 ,使体重增加 ,脾脏和胸腺组织的重量增加。结论 :脾虚证的发生与细胞因子网络调节系统的失衡有关 ,而健脾补肾中药对实验性脾虚证有较好的防治作用 ,脾肾相关理论对实践有指导意义。 相似文献
100.
人类睾丸生精细胞凋亡相关基因TSARG3的克隆 总被引:2,自引:0,他引:2
目的:克隆人类睾丸生精细胞凋亡相关基因TSARG3。方法:从已获得的小鼠稳睾和正常睾丸对照中表达量有明显差异的表达序列标签片段(BE644537)入手,构建人同源表达序列标签重叠群,应用基因特异性引物和载体特异性引物,在睾丸cDNA文库的DN或进行巢式PCR扩增、测序,对测序结果进行生物信息学分析。结果:从睾丸cDNA文库中分离出人类睾丸凋亡相关基因的5’末端而获得全长cDNA,命名为TSARG3,GenBank登录号为AF419291(保密期为1年),同时应用相同方法克隆了该基因在小鼠中的同源基因,GenBank登录号为AF419292。结论:获得人类睾丸生精细胞凋亡相关基因TSARG3,该基因可能与人类睾丸生精细胞凋亡有关。 相似文献