首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2346253篇
  免费   175125篇
  国内免费   3319篇
耳鼻咽喉   32048篇
儿科学   75914篇
妇产科学   62678篇
基础医学   348234篇
口腔科学   63626篇
临床医学   211162篇
内科学   457067篇
皮肤病学   51825篇
神经病学   185376篇
特种医学   88012篇
外国民族医学   489篇
外科学   354152篇
综合类   47472篇
现状与发展   12篇
一般理论   848篇
预防医学   182483篇
眼科学   54345篇
药学   175092篇
  10篇
中国医学   4577篇
肿瘤学   129275篇
  2021年   19009篇
  2019年   19557篇
  2018年   27073篇
  2017年   20375篇
  2016年   22773篇
  2015年   25667篇
  2014年   36138篇
  2013年   53993篇
  2012年   74757篇
  2011年   79496篇
  2010年   47120篇
  2009年   44606篇
  2008年   74697篇
  2007年   79571篇
  2006年   80397篇
  2005年   77884篇
  2004年   74463篇
  2003年   71814篇
  2002年   69462篇
  2001年   108814篇
  2000年   111514篇
  1999年   93554篇
  1998年   27012篇
  1997年   23678篇
  1996年   24075篇
  1995年   22734篇
  1994年   20906篇
  1993年   19719篇
  1992年   72043篇
  1991年   70112篇
  1990年   68421篇
  1989年   65704篇
  1988年   60342篇
  1987年   59159篇
  1986年   55252篇
  1985年   53026篇
  1984年   39324篇
  1983年   33409篇
  1982年   19862篇
  1979年   35885篇
  1978年   25659篇
  1977年   21239篇
  1976年   20334篇
  1975年   21818篇
  1974年   26149篇
  1973年   24803篇
  1972年   23200篇
  1971年   22039篇
  1970年   20252篇
  1969年   19319篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
Nevo  N.  Goldstein  A. L.  Staierman  M.  Eran  N.  Carmeli  I.  Rayman  S.  mnouskin  Y. 《Hernia》2022,26(6):1491-1499
Hernia - The minimally invasive surgical repair of combined inguinal and ventral hernias often requires shifting from one approach or plane to another. The traditional enhanced-view totally...  相似文献   
93.
BackgroundSecond-hand smoking or environmental tobacco smoke is a critical health risk. Children are the most vulnerable to second-hand smoking because of their small bronchial ducts, less developed immunity, and low-physical activity.ObjectivesThe purpose of this study was to ascertain the effects of second-hand smoking on lung functions in athlete and non-athlete school-aged children.MethodsThis observational study included forty-six school-aged children, their age was 8–15 years, assigned to three groups; 2 study groups and 1 control group (n=15). The study groups comprised of 16 football players, and of 15 cyclists. Lung functions were evaluated recording forced vital capacity, forced expiratory volume in 1 sec and peak expiratory flow using digital spirometer.ResultsAll measures were recorded in definite values and the children were also classified into second-hand smoking (SH), or non-exposed to tobacco smoking (NE). The findings presented a significant increase (p<0.05) of the study groups in forced vital capacity, forced expiratory volume in 1 sec and peak expiratory flow solely for the non-exposed children. However, there were non-significant differences between the cyclists and football players or between the passive smoking children and non-exposed children in any of the two study groups (p>0.05).ConclusionThe outcomes of this study suggest beneficial influences of the sports activity on the lung functions, without different influences of the cyclists and football players on the lung functions.  相似文献   
94.
95.
96.
97.
98.
99.
100.
The present study aimed at measuring seropositivities for infection by Ascaris suum and Toxocara canis using the excretory/secretory (E/S) antigens from Ascaris suum (AES) and Toxocara canis (TES) within an indigenous population. In addition, quantification of cytokine expressions in peripheral blood cells was determined. A total of 50 Warao indigenous were included; of which 43 were adults and seven children. In adults, 44.1% were seropositive for both parasites; whereas children had only seropositivity to one or the other helminth. For ascariosis, the percentage of AES seropositivity in adults and children was high; 23.3% and 57.1%, respectively. While that for toxocariosis, the percentage of TES seropositivity in adults and children was low; 9.3% and 14.3%, respectively. The percentage of seronegativity was comparable for AES and TES antigens in adults (27.9%) and children (28.6%). When positive sera were analyzed by Western blotting technique using AES antigens; three bands of 97.2, 193.6 and 200.2 kDas were mostly recognized. When the TES antigens were used, nine major bands were mostly identified; 47.4, 52.2, 84.9, 98.2, 119.1, 131.3, 175.6, 184.4 and 193.6 kDas. Stool examinations showed that Blastocystis hominis, Hymenolepis nana and Entamoeba coli were the most commonly observed intestinal parasites. Quantification of cytokines IFN-γ, IL-2, IL-6, TGF-β, TNF-α, IL-10 and IL-4 expressions showed that there was only a significant increased expression of IL-4 in indigenous with TES seropositivity (p < 0.002). Ascaris and Toxocara seropositivity was prevalent among Warao indigenous.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号