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   810086篇
  免费   53958篇
  国内免费   1426篇
耳鼻咽喉   10794篇
儿科学   27899篇
妇产科学   21162篇
基础医学   124644篇
口腔科学   22490篇
临床医学   71257篇
内科学   154149篇
皮肤病学   19155篇
神经病学   57631篇
特种医学   30272篇
外国民族医学   108篇
外科学   121675篇
综合类   16173篇
现状与发展   2篇
一般理论   182篇
预防医学   56606篇
眼科学   19400篇
药学   61203篇
  3篇
中国医学   2638篇
肿瘤学   48027篇
  2018年   8609篇
  2017年   6756篇
  2016年   7747篇
  2015年   8602篇
  2014年   11653篇
  2013年   17430篇
  2012年   23195篇
  2011年   24198篇
  2010年   14463篇
  2009年   13614篇
  2008年   22830篇
  2007年   24553篇
  2006年   25073篇
  2005年   23762篇
  2004年   23284篇
  2003年   22114篇
  2002年   21604篇
  2001年   42502篇
  2000年   43011篇
  1999年   35578篇
  1998年   9355篇
  1997年   8084篇
  1996年   8180篇
  1995年   7723篇
  1994年   7066篇
  1993年   6602篇
  1992年   26344篇
  1991年   26150篇
  1990年   25506篇
  1989年   25104篇
  1988年   22746篇
  1987年   22042篇
  1986年   21010篇
  1985年   19731篇
  1984年   14481篇
  1983年   12212篇
  1982年   6796篇
  1981年   6107篇
  1979年   13205篇
  1978年   9386篇
  1977年   7869篇
  1976年   7458篇
  1975年   8366篇
  1974年   9599篇
  1973年   9265篇
  1972年   8625篇
  1971年   8032篇
  1970年   7698篇
  1969年   7055篇
  1968年   6489篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A child was brought for evaluation of signs of unilateral chronic progressive sciatic nerve dysfunction found to be due to nerve entrapment in the thigh by a fibrovascular band. Sectioning of the band was followed by marked improvement in the nerve function. Compression by a band is a rare but treatable cause of sciatic neuropathy.  相似文献   
992.
993.
A prospective study was conducted with patients with pulmonary infections who were consecutively admitted to the three community hospitals in Benghu from July 1986 to May 1987, and to the children's hospital in Nanjing from September 1986 to January 1987. Antibodies to Lpi-8, Lm, Ld, and Lg were measured by the micro-agglutination test. During the study period, 150 adult patients (100 pairs sera) and 212 control healthy people and 110 pairs sera of childhood patients and 173 children without respiratory tract infections were investigated. The diagnosis of legionellosis was based on seroconversion (fourfold rise in titer to greater than 1:32 or static titer of greater than 1:32) and clinical and radiographic features of legionnaires' disease. About 11% legionella infection in hospitalized adult patients with pulmonary infections, and about 5.45% in children with atypical pneumonias.  相似文献   
994.
995.
996.
Renal function was evaluated in 104 patients with severe chronic heart failure whom we treated with captopril or enalapril. Seventy patients showed no change or an improvement in renal function (group A), and 34 patients developed functional renal insufficiency (group B). Before converting-enzyme inhibition, group B patients received higher doses of furosemide (p less than 0.02) and had lower central venous pressures (p less than 0.05) than group A patients. After 1 to 3 months of converting-enzyme inhibition, an excessive reduction in left ventricular filling pressure (to less than 15 mm Hg) or mean arterial pressure (to less than 60 mm Hg) was noted in 28 of 34 (82%) patients in group B but in only 22 of 70 patients in group A (31%) (p less than 0.001). At the end of the study, drug-induced azotemia resolved after a reduction in the dosage of diuretics, despite unaltered treatment with captopril and enalapril. Hence, the deterioration of renal function after converting-enzyme inhibition in heart failure is not a toxic or immunologic reaction to therapy but results from specific hemodynamic events that can be ameliorated by sodium repletion.  相似文献   
997.
The purpose of this article is to present the types of marketing tools used in child care and the extent to which they are used. A study of related literature in service marketing reveals that many of the principles of marketing apply in child care. The results of a survey sent to child care centers in Atlanta, Buffalo, Kansas City, San Antonio, and Seattle are presented. The sample included 167 responses. The results are analyzed by geographic location and type of center. Methods of packaging and promoting child care centers are presented.  相似文献   
998.
Renal vascular reactivity in jaundice   总被引:1,自引:0,他引:1  
Obstructive jaundice is associated with a predisposition to hypotension and acute renal failure that may be related to changes in renovascular responsiveness, particularly to norepinephrine (NE). This study was undertaken to investigate changes in vascular response to NE and to determine how these changes are related to prostaglandins. Kidneys from bile duct-ligated (BDL) rabbits (n = 5) were perfused with Krebs' solution at 7.65 ml/min, and the response to varying boluses of NE (0.78 to 6.24 micrograms) was measured as changes in perfusion pressure. When compared with sham-operated control kidneys (n = 8), a significantly blunted response was seen at all doses tested. The NE response was further assessed by measuring force development in mounted segments of main renal arteries (MRAs) (n = 8) and interlobar arteries (ILAs) (n = 6) from BDL rabbits and sham-operated controls (MRA, n = 8; ILA, n = 6). The dose-response curves were significantly depressed in both MRAs and ILAs from BDL animals. In addition, MRAs from sham-operated control animals exhibited decreased response to NE after incubation for 1 hour in jaundiced serum. This attenuated response of MRAs to NE was prevented when indomethacin (5 mg/kg) was given to BDL rabbits before death (n = 9) or when 10(-6)mol/L of indomethacin was added to jaundiced serum during incubation (n = 6). These results indicate that obstructive jaundice induces a decreased vascular contractile response in rabbits to NE and that this effect is mediated by prostaglandins.  相似文献   
999.
1000.
Clinical ecology     
J N Kenyon 《The Practitioner》1986,230(1422):1095-1103
  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