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81.
We evaluated twenty renal transplant subjects at various stages of BKV nephritis (BKVN) for BKV-specific IgG and IgM antibodies using ELISA technique and BKV-DNA using PCR. They were divided as early onset (n = 7), stabilizing (n = 3), resolved (n = 8) and late onset (n = 2) BKVN. BKV-specific antibodies and BKV-DNA were simultaneously determined. The mean BKV-specific IgG level in early onset and stabilizing BKVN were 64 and 39 EIA units, and were significantly lower than 138 EIA units seen in resolved BKVN, P = 0.007, P = 0.008. The mean BKV-specific IgM levels in stabilizing BKVN was higher than resolved BKVN (130 vs 51 EIA units), P = 0.006. Mean plasma BKV loads for each group were 955,925, 5642 and 42 copies/mL of plasma, respectively. Prospective study in six BKVN cases revealed mean IgG, IgM levels and BKV-DNA at the time of diagnosis of BKVN as 39, 110 EIA units and 586,758 copies/mL of plasma, respectively. After a mean period of 5.2 months, IgG level increased to 120 EIA units (p = 0.0058) and had no detectable viral copies in circulation. Recovery from BKVN and elimination of BKV is associated with the development of BKV-specific IgG antibodies and this provides insight into the role of humoral immunity to BKV in the pathogenesis of BKVN.  相似文献   
82.
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   
83.
巢式PCR检测先天性心脏病心脏石蜡标本中B19病毒的感染   总被引:2,自引:0,他引:2  
王晓明  张国成 《医学争鸣》1998,19(3):271-273
目的:探讨微小病毒B19与先天性心脏病(CHD)的相关性及可能致畸机理。方法:采用病例对照研究,病例组为29例CHD尸解心脏组织,对照组为30例同期非先天性畸形尸解心脏组织,应用巢式PCR扩增B19-DNA,单纯疱疹病毒(HSV),兔弓形虫(TOX),巨细胞病毒(CMV),结果:29例CHDB19-DNA5例阳性,全瓿对照组为均阴性(P=0.0237),HSV,TOX两组中均阴性,CMV在两组中均  相似文献   
84.
ltiswellknownthattheskinofextensivelyburnedcasesthemselvesisinsufficienttoprovidecoverageforwounds.Thoughallogeneicskincancoverthewoundstemporari1y,itwillberejectedwithin2-3weeks.Thiscanthreatenthepatient'slifeifthereisnoenoughautogenousskintoreplacetherejectedoneontime.GreenetalL1]reportedthattheburnwoundsofpatientswithextensiveburnscouldbetreatedbytransplantingepidermalautograftsafterautologousepidermalcellsmulti-plyforthousandsoftimesinvltrowithinashortperiodoftime-Butittakesatleast2-3weeks…  相似文献   
85.
86.
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   
87.
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   
88.
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   
89.
90.
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   
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