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81.
采用模拟在人体中使用的实测超声剂量,对体外培养的L-929株细胞进行辐照,通过细胞回复能力试验,观察回复前后的细胞增殖与抑制。对体外培养的人胚肺纤维细胞经1次及5次辐照,观察了DNA及细胞核面积的影响。并通过电镜观察了细胞超微结构的变化。上述实验结果,均提示经辐照后细胞有增殖趋向  相似文献   
82.
为有效开展糖尿病基因治疗,作为第一步,本研究构建了人胰岛素原基因与表达载体PRC/CMV的重组体。首先,从质粒PBCA中酶切回收260bp的人胰岛素原基因片段,利用中间载体PBS.SK构建了含人胰岛素原基困片段的过渡质粒PBS.INS,在此基础上构建了真核细胞表达的人胰岛素基因重组体PRC/CMV.INS。  相似文献   
83.
84.
HBV-M定量检测与HBV-DNA含量水平关系的初步探讨   总被引:2,自引:0,他引:2  
目的 研究乙型肝炎病毒标志物定量检测结果与其HBV-DNA含量的临床关系。方法 采用时间分辨免疫定量和荧光定量-PCR技术,对HBV-DNA和HBV-DNA含量进行检测。结果 在HBsAg/HBeAg/HBcAb,HBsAg/HBcAb/HBcAb,HBeAg/IC及单纯HBcAb阳性的四个组别中,HBV-DNA阳性率分别是97.17%、30.56%、100%和25%;在HBsAg,HBeAg,HBeAb,HBcAb定量检测高,低值两组HBV-DNA含量对比中,HBV-DNA阳性率分别为76.92%、58.14%;100%、97.26%;20.00%、11.42%;64.62%、27.63%。结论 HBV-DNV比HBV-M更能及时准确反映乙型肝炎病毒感染者的病程情况。  相似文献   
85.
目的总结分析1%联苯苄唑凝胶治疗婴儿花斑癣的临床疗效及不良反应。方法对22例婴儿花斑癣患者采用外用1%联苯苄唑凝胶治疗2周,总结分析其临床资料。结果外用1%联苯苄唑凝胶2周后,总有效率达到90.91%,真菌清除率达到86.36%。结论联苯苄唑凝胶治疗婴儿花斑癣安全、有效,不良反应少。  相似文献   
86.
Hepatocyte regeneration has been widely investigated, with the mitotic index and the incorporation of [3H]thymidine being used as regeneration markers. We focused on the induction of DNA replication enzymes, particularly DNA polymerases (pol) α, δ, and ε. Using rat models, we have shown that the activity of pol α in crude liver extract well represents the regenerating capacity of hepatocytes. Using pol α as an indicator, we analyzed liver regeneration in rat models under various conditions: obstructive jaundice, external or internal biliary drainage, and the obstruction of portal vein branches. It has been revealed that the ligation of the common bile duct alone induces a certain amount of hepatocyte proliferation. It was striking that external biliary drainage suppressed regeneration capacity in cholestatic rat liver after partial hepatectomy. The strong regeneration in nonligated lobes induced by portal branch ligation was similar to the liver regeneration seen after partial hepatectomy with respect to the induction of DNA polymerases. Taken together, the aspects of DNA replication, particularly the induction of DNA polymerases, may contribute to shedding new light on the regeneration of human liver. This work was supported in part by a Grant-in-Aid for General Scientific Research and for Cancer Research from the Ministry of Education, Science and Culture, Japan, and by grants from the Uehara Memorial Foundation  相似文献   
87.
We have identified the A3243G heteroplasmic point mutation in mitochondrial DNA from a female patient with headache as the main clinical feature. The mitochondrial origin of her disease was only suspected because of her brother with MELAS syndrome. Morphological and biochemical studies failed to reveal mitochondrial respiratory chain dysfunction in her muscle which contained 65% of mutated mitochondrial DNA molecules. Molecular studies performed among four generations (in the blood of seven subjects) showed the variable transmission of mutated molecules and pointed out the difficulty in giving genetic counsel.  相似文献   
88.
We assessed the mechanics and morphology of the lung in 165 rats treated neonatally with either room air (RA), O2, RA + steroids, or O2, + steroids. Newborn Sprague-Dawley male rats were randomly assigned to these groups. O2,-exposure (0.96-1.0 FiO2 lasted 5 days, and dexamethasone treatment consisted of eight daily S.C. injections of drug or buffer in successive doses of 0.5,0.4.0.3,0.2,0.1, 0.1. 0.1. and 0.1 mg/kg. At 58 days, right ventricular systolic pressure (RVP) was measured. At 60 days, all rats were sacrificed for obtaining lung weight and DNA, saline pressure-volume (P-V) curves, and morphometry. We weighed right ventricles (RV) and left ventricles + septa (LV). Hyperoxia alone did not, but steroid decreased survival rate to 79.4% (95.3% in RA rats, P < 0.02). Only 21 of 40 (52%) O2 + steroids rats survived, less than in both RA groups (P < 0.001). RV weight, RVP and muscularization of alveolar duct arteries were significantly increased in O2 vs. RA rats. In RA + steroids rats, weight of the LV was decreased but RV, RVP, and lung vasculature were not affected. These effects were additive in the O2 + steroid group. Wet lung weights and DNA were increased for RA + steroid rats over all others. O2 and steroids shifted the P-V curve to the left and O2+ steroids still further. Maximal lung volume increased significantly with RA + steroids and still further in O2 + steroids but not in O2 alone. O2 and steroids significantly increased the mean linear intercept and O2 + steroids even more so. In O2- and steroid-treated rats, the parenchymal air space increased. In conclusion, both neonatal hyperoxia and steroid administration caused aberrations in the growth of lung and connective tissue. The effects of the two were additive. The vascular system, maximal lung volume, and DNA responded differently, presumably by different modes of action. Pediatr Pulmonol. 1993; 16:81–88. © 1993 Wiley-Liss, Inc.  相似文献   
89.
Recombinant fowlpox virus inducing protective immunity in non-avian species   总被引:22,自引:0,他引:22  
The natural host of fowlpox virus is limited to avian species. When inoculated into non-avian tissue culture cells, however, fowlpox virus can initiate an abortive infection. A fowlpox virus was engineered to express rabies virus glycoprotein. On inoculation of the recombinant virus into either avian (permissive) or non-avian (non-permissive) cells, the rabies glycoprotein was expressed as a membrane-associated antigen. Inoculation of the fowlpox virus recombinant into six different species of mammal resulted in specific immune responses to both fowlpox antigens and to rabies glycoprotein. In mice, cats and dogs the immune response was sufficient to protect against a live rabies virus challenge. The results demonstrate the utility of a fowlpox virus vector in immunizing non-avian species against rabies in the absence of productive viral replication of the fowlpox vector.  相似文献   
90.
1. Aldosterone levels in patients with unilateral aldosterone-producing adenomas may be responsive or unresponsive to the renin-angiotensin system, with the former often previously misdiagnosed as bilateral adrenal hyperplasia. 2. In tumours from patients in the responsive subgroup, renin mRNA is expressed in greater amounts than in tumours from patients in the unresponsive subgroup, or in normal adrenals. 3. We compared the frequency of four renin gene polymorphisms in peripheral blood DNA from the two subgroups and found significant associations between BglI, TaqI and HinfI restriction fragment length polymorphisms (RFLP) and aldosterone responsiveness. 4. Allelic variation in the constitutive renin gene was associated with a specific cause of hypertension.  相似文献   
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