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991.
捕捉法ELISA检测登革热病人血清IgM抗体用于快速诊断   总被引:1,自引:0,他引:1  
张大  赵蜀崖 《病毒学报》1992,8(4):349-353
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992.
The association between xeroderma pigmentosum group D (XPD) Lys751Gln polymorphism and bladder cancer (BC) susceptibility was investigated by two meta-analyses, however, their results were contrary. We conjecture the reason might be the sample size, thus we performed this updated and cumulative meta-analysis using the Comprehensive Meta-Analysis software. We searched PubMed up to August 25th, 2013 and yielded 20 published articles with 21 case–control trails including 6,836 BC patients and 8,251 controls. The meta-analysis results showed that XPD Lys751Gln polymorphism was borderline significantly associated with BC susceptibility for overall population [Gln vs. Lys: OR 1.07, 95 % CI 1.01–1.12, P = 0.01; Gln/Gln vs. Lys/Lys: OR 1.15, 95 % CI 1.03–1.29, P = 0.01; Gln/Gln vs. (Lys/Gln + Lys/Lys): OR 1.13, 95 % CI 1.02–1.26, P = 0.02]. The cumulative meta-analysis according to the publication year showed the CI became increasingly narrower and tended to have statistical significance for the studies incessantly accumulated. In the subgroup analysis according to ethnicity, there was a significant association in Asian population and no association in Caucasian population. There was no publication bias detected. However, due to the limitations and cumulative analysis result of this meta-analysis, more well-designed and larger studies with risk factors adjusted are suggested to be performed to obtain a conclusive result on this topic.  相似文献   
993.
994.
In addition to the classic genomic effects, it is well known that glucocorticoids also have rapid, nongenomic effects on neurons. In the present study, the effect of corticosterone (CORT) on ATP-induced Ca2+ mobilization in cultured dorsal root ganglion (DRG) neurons were detected with confocal laser scanning microscopy using fluo-4/AM as a calcium fluorescent indicator that could monitor real-time alterations of intracellular calcium concentration ([Ca2+]i). ATP, an algesic agent, caused [Ca2+]i increase in DRG neurons by activation of P2X receptor. Pretreatment with CORT (1 nM–1 μM for 5 min) inhibited ATP-induced [Ca2+]i increase in DRG neurons. The rapid inhibition of ATP-induced Ca2+ response by CORT was concentration-dependent, reversible and could be blocked by glucocorticoid receptor antagonist RU38486 (10 μM). Furthermore, the inhibitory effect of CORT was abolished by protein kinase A inhibitor H89 (10 μM), but was not influenced by protein kinase C inhibitor Chelerythrine chloride (10 μM). On the other hand, membrane-impermeable bovine serum albumin-conjugated corticosterone had no effect on ATP-induced [Ca2+]i transients. These observations suggest that a nongenomic pathways may be involved in the effect of CORT on ATP-induced [Ca2+]i transients in cultured DRG neurons.  相似文献   
995.

Objectives

To assess HIV incidence and its associated risk factors among young men who have sex with men (YMSM) in urban areas, China.

Design

The study used a prospective cohort study design and standard diagnostic tests.

Methods

A twelve-month prospective cohort study was conducted among YMSM (18–25 years old) in 8 large cities in China. The participants were recruited via snowball sampling. A total of 1102 HIV-negative YMSM completed baseline assessment, 878 YMSM participants completed 6-month follow-up, and 902 completed 12-month follow-up. HIV was screened by an enzyme-linked immunosorbent assay and confirmed with Western Blot. Syphilis was screened via rapid plasma reagent and confirmed by treponema pallidum particle agglutination assay.

Results

78 HIV seroconversions were identified within 1168.4 person-year observations yielding an incidence rate of 6.7 per 100 person-years. HIV seroconversion was associated with non-student status (RR = 2.61, 90% CI = 1.3–5.26), low HIV transmission knowledge (RR = 8.87, 90% CI = 2.16–36.43), and syphilis infection (RR = 5.04, 90% CI = 2.57–9.90).

Conclusions

Incidence of HIV among YMSM is high in urban areas of China. Interventions measures are required to contain the HIV epidemic within this population.  相似文献   
996.
附子多糖FⅠ的分离纯化及部分理化性质研究   总被引:1,自引:0,他引:1  
白附片经热水抽提、Sevag法脱蛋白、乙醇沉淀、DEAE-C32柱层析分离,再通过Sephadex G-200柱层析进一步纯化,得到一种纯白色粉末状多糖,糖含量为97%,平均分子量为2.6×105,熔点为270℃.经完全酸水解、薄层层析、红外光谱分析,证明为葡聚糖.  相似文献   
997.
The term leukopoiesis describes processes leading to the production and regulation of white blood cells. It is based on stem cells differentiation and may exhibit abnormalities resulting in severe diseases, such as cyclical neutropenia and leukemias. We consider a nonlinear system of two equations, describing the evolution of a stem cell population and the resulting white blood cell population. Two delays appear in this model to describe the cell cycle duration of the stem cell population and the time required to produce white blood cells. We establish sufficient conditions for the asymptotic stability of the unique nontrivial positive steady state of the model by analysing roots of a second degree exponential polynomial characteristic equation with delay-dependent coefficients. We also prove the existence of a Hopf bifurcation which leads to periodic solutions. Numerical simulations of the model with parameter values reported in the literature demonstrate that periodic oscillations (with short and long periods) agree with observations of cyclical neutropenia in patients.  相似文献   
998.
目的探讨卵巢肿瘤MVD与TP的关系。方法免疫组化检测101例卵巢肿瘤MVD、TP。结果101例卵巢肿瘤中,腺瘤、交界性肿瘤、卵巢癌三种不同性质卵巢肿瘤中MVD(个/0·03mm2)计数分别为12·87±6·11、25·96±7·09、33·01±10·21,各组间比较差异均有极显著性意义(P<0·01);TP阳性表达率分别为12%(3/25)、33%(7/21)、71%(39/55),卵巢癌与腺瘤、交界性肿瘤TP比较均有极显著性差异(P<0·01)。MVD≤21个/0·03mm2的卵巢癌中TP阳性表达率较低(58·8%,20/34),MVD>21个/0·03mm2的卵巢癌中TP阳性表达率较高(90·5%,19/21),两者比较差异有极显著性意义(P<0·01)。结论1.卵巢肿瘤组织中MVD增高、TP表达上调是反映卵巢肿瘤生物学行为恶性进展的有用指标。2.卵巢癌MVD与TP表达呈正相关,MVD>21个/0·03mm2或MVD与TP指数相应上调的卵巢癌可能生长速度较快,恶性程度较高,提示预后不良。这一发现对进一步探讨卵巢癌的发生发展提供了分子学基础。  相似文献   
999.
凋亡抑制基因livin与survivin在乳腺癌中的表达差异   总被引:4,自引:2,他引:4  
目的探讨凋亡抑制基因livin在乳腺癌发生、发展中的作用及其与survivin基因的表达和乳腺癌生物学行为之间的关系。方法采用逆转录聚合酶链反应(RT-PCR)检测44例乳腺癌组织、40例癌旁正常组织及4个乳腺癌细胞系中livinmRNA和survivin mRNA的表达,并用免疫组化(IHC)EnVision法检测上述组织和细胞中livin和survivin蛋白的表达。结果livin mRNA和survivin mRNA在乳腺癌组织中的阳性表达率分别为72.7%(32/44)和61.4%(27/44),在癌旁正常组织中的阳性率分别为7.50%(3/40)和5.00%(2/40),二者在癌组织中的表达均显著高于在正常组织中的表达(P<0.01)。livin和survivin蛋白表达情况与mRNA结果相似(P<0.01)。livin和survivin在乳腺癌组织中的表达无显著相关性(P>0.05)。4个乳腺癌细胞系中均有survivin mRNA和蛋白的表达,而MCF-7及MDA-MB-435细胞系中呈阴性表达。survivin基因在伴有淋巴结转移的乳腺癌组织中的表达明显高于无淋巴结转移的乳腺癌组织(P=0.0047),livin在雌激素受体(ER)阴性或者Her2/neu阳性表达的乳腺癌中的阳性率有升高的趋势,但并无显著性差异(P>0.05)。结论livin和survivin基因在人乳腺癌组织中表达上调,提示其可能在乳腺癌发生、发展中起重要促进作用,sur-vivin和淋巴结转移的密切关系表明它的高表达可能反映患者较差的预后。livin和survivin基因一样可能成为乳腺癌治疗中的一个靶基因。  相似文献   
1000.
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