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161.
162.
Occlusion of varicoceles wih detachable balloons   总被引:1,自引:0,他引:1  
  相似文献   
163.
荧光分光光度法测定姜黄制剂中的姜黄素   总被引:11,自引:0,他引:11  
用荧光分光光度法测定姜黄胶囊制剂中的姜黄素。以四氢呋喃为溶剂,姜黄素的激发波长和发射波长分别为Ex=442nm,Em=475nm。姜黄素标准曲线的线性范围为0.010~0.40fg/ml。最低检测浓度5ng/ml;回收率100.00%±0.28%;RSD<1%。本法操作简便、快速、灵敏,适用于姜黄制剂中姜黄素的含量。  相似文献   
164.
BACKGROUND: The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1- infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described. STUDY DESIGN AND METHODS: Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing. RESULTS: Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+. CONCLUSION: The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high- risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts.  相似文献   
165.

Background and purpose:

K+ channels play a role in the proliferation of cancer cells. We have investigated the effects of specific K+ channel inhibitors on basal and oestrogen-stimulated proliferation of breast cancer cells.

Experimental approach:

Using the mammary adenocarcinoma cell line MCF-7 we assayed cell proliferation by radiolabelled thymidine incorporation in the absence or presence of various K+ channel inhibitors with or without 17β-oestradiol.

Key results:

Inhibitors of Kv10.1 and KCa3.1 K+ channels suppressed basal proliferation of MCF-7 cells, but not oestrogen-stimulated proliferation. TRAM-34, a specific inhibitor of KCa3.1 channels increased or decreased cell proliferation depending on the concentration. At intermediate concentrations (3–10 µM) TRAM-34 increased cell proliferation, whereas at higher concentrations (20–100 µM) TRAM-34 decreased cell proliferation. The enhancement of cell proliferation caused by TRAM-34 was blocked by the oestrogen receptor antagonists ICI182,780 and tamoxifen. TRAM-34 also increased progesterone receptor mRNA expression, decreased oestrogen receptor-α mRNA expression and reduced the binding of radiolabelled oestrogen to MCF-7 oestrogen receptor, in each case mimicking the effects of 17β-oestradiol.

Conclusions and implications:

Our results demonstrate that K+ channels Kv10.1 and KCa3.1 play a role in basal, but not oestrogen-stimulated MCF-7 cell proliferation. TRAM-34, as well as inhibiting KCa3.1, directly interacts with the oestrogen receptor and mimics the effects of 17β-oestradiol on MCF-7 cell proliferation and gene modulation. Our finding that TRAM-34 is able to activate the oestrogen receptor suggests a novel action of this supposedly specific K+ channel inhibitor and raises concerns of interpretation in its use.  相似文献   
166.
李会文  杨志伟  李建卫 《医学争鸣》2005,26(23):2148-2148
0引言在急性重度有机磷农药中毒(AOPP)救治过程中,早期的内科常规处理,结合抗胆碱药及复能剂的应用,并积极进行肠道水疗,血液灌流,后期营养支持等综合救治,能提高AOPP在基层医院的抢救成功率、存活率.我院2000-3/2005-03收治32例重度AOPP患者,获得满意治疗效果.  相似文献   
167.
目的利用4种不同支架材料构建复合式口腔黏膜,并比较其组织结构特点。方法体外培养人口腔黏膜的成纤维细胞和角质形成细胞,在4种支架材料中加入成纤维细胞,培养7d后,在支架表面加入角质形成细胞,培养4d后,移至气-液界面继续培养7d。苏木精-伊红染色镜下观察构建的复合式口腔黏膜的组织形态学特点。结果 4种支架均可构建形成复层上皮。其中,上皮层与脱细胞真皮基质材料(de-epidermised dermis,DED)结合紧密,形成的人工黏膜有明显的上皮钉突。不同于以往报道,上皮层与Alloderm结合并不十分紧密。以胶原凝胶为基质形成的人工口腔黏膜最厚,有明显分层。以胶原海绵-胶原凝胶为基质形成的复层上皮在部分区域长入至胶原海绵的空隙中。结论以DED和胶原凝胶为支架构建的口腔黏膜更接近于天然结构,而后者脆性较大,限制了其临床应用的可能。  相似文献   
168.
The alcohol industry have attempted to position themselves as collaborators in alcohol policy making as a way of influencing policies away from a focus on the drivers of the harmful use of alcohol (marketing, over availability and affordability). Their framings of alcohol consumption and harms allow them to argue for ineffective measures, largely targeting heavier consumers, and against population wide measures as the latter will affect moderate drinkers. The goal of their public relations organisations is to ‘promote responsible drinking’. However, analysis of data collected in the International Alcohol Control study and used to estimate how much heavier drinking occasions contribute to the alcohol market in five different countries shows the alcohol industry's reliance on the harmful use of alcohol. In higher income countries heavier drinking occasions make up approximately 50% of sales and in middle income countries it is closer to two‐thirds. It is this reliance on the harmful use of alcohol which underpins the conflicting interests between the transnational alcohol corporations and public health and which militates against their involvement in the alcohol policy arena. [Caswell S, Callinan S, Chaiyasong S, Cuong PV, Kazantseva E, Bayandorj T, Huckle T, Parker K, Railton R, Wall M. How the alcohol industry relies on harmful use of alcohol and works to protect its profits. Drug Alcohol Rev 2016;35:661–664]  相似文献   
169.
170.
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