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   2349739篇
  免费   171633篇
  国内免费   3331篇
耳鼻咽喉   32049篇
儿科学   75892篇
妇产科学   62685篇
基础医学   348166篇
口腔科学   63633篇
临床医学   211343篇
内科学   457269篇
皮肤病学   51727篇
神经病学   185268篇
特种医学   88006篇
外国民族医学   489篇
外科学   353854篇
综合类   47509篇
现状与发展   12篇
一般理论   848篇
预防医学   182731篇
眼科学   54325篇
药学   175102篇
  11篇
中国医学   4575篇
肿瘤学   129209篇
  2021年   18980篇
  2019年   19536篇
  2018年   27057篇
  2017年   20357篇
  2016年   22745篇
  2015年   25638篇
  2014年   36094篇
  2013年   53952篇
  2012年   74674篇
  2011年   79405篇
  2010年   47055篇
  2009年   44564篇
  2008年   74607篇
  2007年   79477篇
  2006年   80295篇
  2005年   77777篇
  2004年   74365篇
  2003年   71689篇
  2002年   69362篇
  2001年   108737篇
  2000年   111450篇
  1999年   93494篇
  1998年   26990篇
  1997年   23658篇
  1996年   24054篇
  1995年   22715篇
  1994年   20893篇
  1993年   19712篇
  1992年   72000篇
  1991年   70069篇
  1990年   68391篇
  1989年   65663篇
  1988年   60302篇
  1987年   59125篇
  1986年   55217篇
  1985年   53004篇
  1984年   39311篇
  1983年   33396篇
  1982年   19858篇
  1979年   35866篇
  1978年   25651篇
  1977年   21230篇
  1976年   20332篇
  1975年   21816篇
  1974年   26148篇
  1973年   24802篇
  1972年   23200篇
  1971年   22037篇
  1970年   20247篇
  1969年   19315篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
951.
952.
Migräne     
Migraine is a prevalent disease that affects women more frequently than men. A particular trigger for migraine is the perimenstrual period. Acute migraine attacks during menstruation are treated similarly to nonmenstrual attacks, e.g., with analgesics or triptans. In women with pure menstrual migraine, short-term prophylaxis can be performed with nonsteroidal anti-inflammatory drugs (NSAIDs), estrogens, or low-dose triptans. During pregnancy migraine improves. After menopause frequency and severity of migraine attacks improve.  相似文献   
953.
954.
955.
956.
957.
Operator's determined (D) and stochastic (S) performance depends on the level of readiness and synchronization of the frontoparietal and parietooccipital cortex areas. The developed feedback algorithm was tested in two series of experiments with volunteered subjects doing computer simulation tasks. The experiments showed feasibility to elaborate feedback adaptive control skills that will sustain for a month period.  相似文献   
958.
Head-down tilting of primates (HOT) is a universal method of studying the hypokinetic syndrome effects on functionality of various body systems. Clinical biochemical blood assay was performed in a 25-day HDT experiment (-5 degrees) with 11 Macaca rhesus. One group of animals was kept tilted all the time through, whereas the other was periodically returned into the orthostatic position for 30 to 120 minutes 4-5 times a week. Dry chemistry was employed in biochemical analysis of blood serum and enzyme immunodetection (EID) in measuring blood hormones. As a rule, the biochemical parameters of primates' serum were within the physiological norm range. Shifts in protein, carbohydrate and mineral metabolism were sought for and enzymic activity in blood serum and hormone concentrations were determined. HDT did not produce noteworthy changes in blood concentrations of somatotropic hormone, thyrotrophic hormone (TTH), triiodothyronine (T3), thyroxine (T4) or cortisol. Animals of both groups showed statistically reliable decrease in blood osteocalcine. The preventive complex did not contribute materially to the control of metabolic homeostasis and endocrine function of the primates adapting to the 25-day HDT.  相似文献   
959.
Experiments on Japanese quail embryogenesis on a background of chronic exposure to gamma- and neutron doses comparable with the doses of ionized radiation inside the orbital space stations Mir and ISS, and exploration vehicles gave evidence that permanent absorption of low gamma-doses (0,15 cgy/d) did not impact development of the Japanese quail embryos. On the contrary, the neutron dose of 200 microgy/d imparted by the neutron flux of 30 particles/cm2s was hazardous to embryos as it caused morphological disorders in 12% of embryos.  相似文献   
960.
AIMS: A rare case of the insulin autoimmune syndrome (IAS) accompanied by insulin receptor anomaly is reported. METHODS: Antibodies to insulin and insulin receptor were determined in the patient with severe hypoglycaemia before and after the treatment with prednisolone. RESULTS: Titers of antibody to insulin and insulin receptors were 73.0% and 41.5%, respectively. Drug-induced lymphocyte stimulation tests were all negative for the suspicious drugs. Her HLA-DR was DRB1*0403/04051. Following steroid therapy, the formation of antibodies was suppressed and alleviated her symptoms. Scatchard analysis yielded findings specific to polyclonal antibodies. CONCLUSIONS: The changes in autoantibodies resulted in alleviation of the hypoglycemic symptoms as a result of steroid therapy.  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