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   2540798篇
  免费   177375篇
  国内免费   3395篇
耳鼻咽喉   33514篇
儿科学   82956篇
妇产科学   66064篇
基础医学   368321篇
口腔科学   65698篇
临床医学   225033篇
内科学   492331篇
皮肤病学   52822篇
神经病学   203526篇
特种医学   97634篇
外国民族医学   492篇
外科学   386570篇
综合类   50601篇
现状与发展   12篇
一般理论   910篇
预防医学   201332篇
眼科学   57431篇
药学   185450篇
  11篇
中国医学   5223篇
肿瘤学   145637篇
  2021年   19337篇
  2019年   19903篇
  2018年   47760篇
  2017年   36843篇
  2016年   42064篇
  2015年   26961篇
  2014年   37453篇
  2013年   55665篇
  2012年   82497篇
  2011年   100341篇
  2010年   64799篇
  2009年   56273篇
  2008年   94661篇
  2007年   102552篇
  2006年   82407篇
  2005年   81804篇
  2004年   79885篇
  2003年   78498篇
  2002年   74143篇
  2001年   109366篇
  2000年   112338篇
  1999年   94002篇
  1998年   27555篇
  1997年   24265篇
  1996年   24476篇
  1995年   23149篇
  1994年   21275篇
  1993年   20071篇
  1992年   72326篇
  1991年   70446篇
  1990年   68746篇
  1989年   65949篇
  1988年   60541篇
  1987年   59369篇
  1986年   55432篇
  1985年   53249篇
  1984年   39562篇
  1983年   33630篇
  1982年   20169篇
  1979年   36073篇
  1978年   25822篇
  1977年   21321篇
  1976年   20491篇
  1975年   21889篇
  1974年   26257篇
  1973年   24870篇
  1972年   23247篇
  1971年   22076篇
  1970年   20313篇
  1969年   19378篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
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   
92.
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   
93.
94.
95.
96.
97.
98.
99.
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   
100.
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