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   2349107篇
  免费   175469篇
  国内免费   3316篇
耳鼻咽喉   32101篇
儿科学   76135篇
妇产科学   62773篇
基础医学   348646篇
口腔科学   63647篇
临床医学   211567篇
内科学   457376篇
皮肤病学   51829篇
神经病学   185530篇
特种医学   88165篇
外国民族医学   489篇
外科学   354667篇
综合类   47620篇
现状与发展   12篇
一般理论   849篇
预防医学   182848篇
眼科学   54365篇
药学   175349篇
  12篇
中国医学   4578篇
肿瘤学   129334篇
  2021年   19038篇
  2019年   19613篇
  2018年   27136篇
  2017年   20421篇
  2016年   22812篇
  2015年   25724篇
  2014年   36213篇
  2013年   54112篇
  2012年   74887篇
  2011年   79645篇
  2010年   47210篇
  2009年   44694篇
  2008年   74860篇
  2007年   79705篇
  2006年   80526篇
  2005年   78027篇
  2004年   74593篇
  2003年   71895篇
  2002年   69567篇
  2001年   108849篇
  2000年   111575篇
  1999年   93599篇
  1998年   27039篇
  1997年   23711篇
  1996年   24117篇
  1995年   22775篇
  1994年   20932篇
  1993年   19763篇
  1992年   72094篇
  1991年   70161篇
  1990年   68464篇
  1989年   65730篇
  1988年   60369篇
  1987年   59187篇
  1986年   55271篇
  1985年   53078篇
  1984年   39363篇
  1983年   33447篇
  1982年   19893篇
  1979年   35904篇
  1978年   25673篇
  1977年   21259篇
  1976年   20364篇
  1975年   21852篇
  1974年   26180篇
  1973年   24834篇
  1972年   23228篇
  1971年   22072篇
  1970年   20280篇
  1969年   19341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