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21.
为探讨新婚前后人群对避孕方法(特别是紧急避孕方法)的知识、态度和使用以及新婚前后人群对紧急避孕的需求及对推广EC的意愿的建议。采用描述性流行病学研究方法,以郑州市新婚学校为研究现场,直接收集第一手数据。采用EPI INF6.04软件包,和SPSS7.5 FOR WINDOW95软件包,进行数据处理、统计与分析。统计分析的主要指标有:频数分布,单因素分析,logistic多元回归分析等。结果平均年龄26.41岁,女性占49.4%。在第一次同房时,仅有46.4%的人使用过避孕方法。第一次同房时最常用的避孕方法是避孕套(76.1%)。在女性应答者中,25岁以下开始同房者占76.6%,有9.3%的人有过人工流产史。88.2%的人每周有1~6次同房。有43.2%的人听说过EC方法,有35.9%的人听说过紧急避孕片,有29.9%的人知道使用EC片有时间限制,有24.7%的人听说过上环可作为紧急避孕方法,有17.4%的人知道上环紧急避孕方法有时间限制。仅有12.9%的人使用过某种事后避孕方法,其中有事后3天内使用者占82.0%。92.6%的人赞成开展EC教育。73.7%的人认为,应在未婚青少年中开展EC教育。80.7%的人认为,在本单位进行EC教育是可行的。应答者认为,最易的接受的EC教育形式依次为:阅读材料(40.4%),录相(20.6%)和讲课(15.7%)。认为EC的最可靠的信息来源 相似文献
22.
Gamma delta T cells in rhesus monkeys and their response to simian immunodeficiency virus (SIV) infection. 总被引:1,自引:0,他引:1 下载免费PDF全文
The principal cause of IL-2 deficiency, a common feature of both murine lupus and human SLE, remains obscure. Recent studies of our own as well as others have shown that dehydroepiandrosterone (DHEA), an intermediate compound in testosterone synthesis, significantly up-regulates IL-2 production of T cells, and that administration of exogenous DHEA or IL-2 via a vaccinia construct to murine lupus dramatically reverses their clinical autoimmune diseases. Thus, we have examined serum levels of DHEA in patients with SLE to test whether abnormal DHEA activity is associated with IL-2 deficiency of the patients. We found that nearly all of the patients examined have very low levels of serum DHEA. The decreased DHEA levels were not simply a reflection of a long term corticosteroid treatment which may cause adrenal atrophy, since serum samples drawn at the onset of disease, which are devoid of corticosteroid treatment, also contained low levels of DHEA. In addition, exogenous DHEA restored impaired IL-2 production of T cells from patients with SLE in vitro. These results indicate that defects of IL-2 synthesis of patients with SLE are at least in part due to the low DHEA activity in the serum. 相似文献
23.
An affinity chromatography technique was utilized to isolate and purify the receptors of Escherichia coli K88ac(+) fimbriae from the mucus of the small intestines of newborn piglets. Purified K88ac+ fimbriae were covalently immobilized onto a beaded agarose matrix (Sepharose 4B). The immobilized fimbriae were used for the affinity purification of the K88ac+ receptors. Only two major proteins were tightly and specifically bound to the immobilized fimbriae after the column containing bound receptor was washed exhaustively with a buffer containing a high concentration of salt and a detergent. The receptors were eluted as a single component at a low pH. The isolated proteins were then subjected to enzyme-linked immunosorbent assay, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and Western blot (immunoblot) analyses. The two proteins were of high purity, were responsible for nearly all of the fimbrial binding capacity of the crude mucus, and had molecular masses of 26 and 41 kDa. The method for isolation of E. coli binding proteins is simple and yields purified intestinal receptors in a single chromatographic run. The intestinal mucus of different piglets has different proportions of the two receptor proteins. 相似文献
24.
Human macrophages acquire a hyporesponsive state of tumor necrosis factor alpha production in response to successive Mycobacterium avium serovar 4 stimulation. 下载免费PDF全文
Human macrophages (M phi) from most donors respond to inoculation with Mycobacterium avium serovar 4 (M. avium) by tumor necrosis factor alpha (TNF-alpha) production, which is of critical importance for proper defense against microorganisms. An initial infection of M phi with M. avium results in an incapacity to accumulate TNF-alpha mRNA after reinfection with M. avium, indicating adaptation to a hyporesponsive state by preexposure of the cells to M. avium. Adaptation to stimulation with M. avium is abrogated by the cyclooxygenase inhibitor indomethacin. In the presence of prostaglandin E2, indomethacin-exposed, M. avium-treated M phi remain unresponsive to a subsequent M. avium stimulus to increase steady-state TNF-alpha mRNA, suggesting that prostaglandin E2 is instrumental for the adaptation to an M. avium challenge. TNF-alpha mRNA accumulation induced by a second M. avium stimulus in the presence of indomethacin is blocked by the protein tyrosine kinase inhibitor herbimycin. In contrast, the initial M phi response to M. avium is inhibited by staurosporin, an inhibitor of phospholipid Ca(2+)-dependent protein kinases, indicating that the initial and the successive TNF-alpha responses to M. avium are dependent on different mechanisms. 相似文献
25.
Photodynamic therapy (PDT) is a clinical approach that utilizes light-activated drugs for the treatment of a variety of pathologic conditions. Human poorly (CNE2) and moderately differentiated (TW0-1) human nasopharyngeal carcinoma (NPC) cells undergo rapid apoptosis when treated with PDT sensitized with Hypocrellin A (HA) and Hypocrellin B (HB). It has been shown that these compounds have a strong photodynamic effect on tumors and viruses. The initiating events of PDT sensitized HA and HB-induced apoptosis are poorly defined. In the current study, we sought to determine whether Fas/FasL upregulation and involvement of mitochondrial events are an early event in HA and HB-treated PDT induced apoptosis. Loss of mitochondrial transmembrane potential, release of cytochrome c, involvement of caspases-8 and -3 and the status caspase-3 specific substrate PARP, were evaluated in PDT treated tumor cells. Photoactivation of HA and HB enhanced both CD95/CD95L expression and induced CD95-signaling dependent cell death in all tumor cell lines studied. CD95/ CD95L expression appeared within 2 h following light activation and appeared to be a primary event in PDT induced apoptosis. Furthermore, these results indicate that release of mitochondrial cytochrome c into the cytoplasm is a secondary event following the activation of initiator caspase-8 preceding caspase-3 activation, cleavage of PARP and DNA fragmentation. Cytochrome c appeared in the cytosol within 2-3 h post PDT. Cleavage of PARP was observed at 3-4 h following PDT and caspase-3 specific inhibitor DEVD-CHO and broad-spectrum caspases inhibitor z-VAD-fmk blocked caspase-3 activation and PARP cleavage suggesting that caspase-3 plays an important role in HA and HB-induced apoptosis. 相似文献
26.
酒客乐对酒精性肝损伤大鼠血清微量元素含量的影响 总被引:2,自引:0,他引:2
目的 :观察酒客乐对酒精性肝损伤大鼠血清微量元素含量的影响。方法 :用白酒、吡唑、橄榄油的混合液制成酒精性肝损伤模型 ,酒客乐冲剂为防治用药 ,观察血清微量元素Cu、Zn、Se及Mn含量的变化。结果 :与正常组比较 ,肝损伤组血清Se、Cu、Zn含量下降 (P <0 0 1或P <0 0 5 ) ;而防治组血清Se、Cu、Zn含量得以回升 ,其中Zn含量升至 3 2± 0 2 4ug ml,明显高于损伤组 (P <0 0 1)。结论 :酒客乐可通过补充酒精性肝损伤大鼠某些血清微量元素含量间接发挥清除自由基 ,稳定生物膜的作用 相似文献
27.
目的 :研究硅凝胶型乳房假体植入大鼠体内后凝胶外渗对机体的影响。方法 :取 40只健康SD雌性大鼠分成A、B、C、D 4组 ,A、B、C 3组分别植入实验用完整的硅凝胶型假体、刺破的硅凝胶型假体及生理盐水充注型假体于大鼠背侧皮下 ,D组为空白对照。术前测出血液中有机硅的浓度。 6个月后取出假体观察 ,进行假体包膜组织学检查及大鼠血液中术后有机硅的浓度测定。结果 :A、B、C 3组纤维包膜组织学特征无明显差异 ,B组纤维包膜中光镜下发现外渗的凝胶颗粒。术后与术前 4组大鼠间血液中有机硅的浓度比较 ,差异均无显著性。结论 :完整的硅凝胶假体、人为刺破外壳的硅凝胶假体与生理盐水充注型假体的组织学反应无明显差异 ,外渗的凝胶局限在纤维包膜的内层 ,也不会随血液或淋巴到机体其他部位。 相似文献
28.
目的 :探讨生长激素对糖尿病及其微血管病变的影响。方法 :采用放射免疫法测定 6 7例Ⅱ型糖尿病患者及 18例正常人的血清生长激素 (GH)及胰岛素 (INS)水平。结果 :糖尿病合并微血管病变组 ,空腹生长激素 (FGH)明显高于正常对照组 (P <0 .0 1)及糖尿病无微血管病变组 (P <0 .0 1)。糖尿病无微血管病变组的FGH与正常对照组的FGH相比未见明显差异 (P >0 .0 5 )。餐后 2h的生长激素 (PGH)在 3组之间均无显著差异 (P >0 .0 5 )。FGH与HbA1c、空腹血糖 (FBS)呈正相关 (r=0 .5 46 ,P <0 .0 1;r=0 .437,P <0 .0 1) ,与UAER呈正相关 (r=0 .486 ,P <0 .0 1) ;FGH与病程无相关 (r=0 .2 2 ,P >0 .0 5 ) ,与FINS无相关 (r =- 0 .0 2 9,P >0 .0 5 )。结论 :GH水平的增高 ,与糖代谢紊乱有关 ,参与了糖尿病微血管病变的发生。 相似文献
29.
30.
人类巨细胞病毒感染对人胚肺细胞HOXB1,HOXB5,HOXB6及HOXB9基因表达的影响 总被引:3,自引:0,他引:3
目的 :研究人胚肺 (HEL)细胞HOXB1,HOXB5 ,HOXB6及HOXB9基因的表达状态及人类巨细胞病毒(HCMV)感染对上述基因表达的影响。方法 :采用半定量逆转录 -聚合酶链反应 (RT -PCR)技术。结果 :①HEL细胞表达HOXB5和HOXB6 ,但不表达HOXB1和HOXB9;②HCMV感染后 ,HEL细胞HOXB6基因的表达上调 ,且被HCMV诱导表达HOXB9T ,而HOXB5基因的表达无明显改变 ,HOXB1基因仍旧不表达 ;③全反式维甲酸 (ATRA)能上调HCMV感染后HOXB9基因的表达 ,但对HCMV感染晚期HOXB6基因的表达有抑制作用。结论 :HCMV能诱导HOXB6和HOXB9基因表达异常 ,这可能在先天性HCMV感染导致胚胎发育畸形中起重要作用 相似文献