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   2352276篇
  免费   171847篇
  国内免费   3313篇
耳鼻咽喉   32118篇
儿科学   75913篇
妇产科学   62691篇
基础医学   348334篇
口腔科学   63683篇
临床医学   211671篇
内科学   458025篇
皮肤病学   51745篇
神经病学   185680篇
特种医学   88046篇
外国民族医学   489篇
外科学   354005篇
综合类   47520篇
现状与发展   12篇
一般理论   848篇
预防医学   182838篇
眼科学   54396篇
药学   175238篇
  48篇
中国医学   4588篇
肿瘤学   129548篇
  2021年   19358篇
  2019年   19546篇
  2018年   27066篇
  2017年   20364篇
  2016年   22772篇
  2015年   25658篇
  2014年   36106篇
  2013年   53965篇
  2012年   74695篇
  2011年   79415篇
  2010年   47061篇
  2009年   44570篇
  2008年   74632篇
  2007年   79501篇
  2006年   80320篇
  2005年   77804篇
  2004年   74398篇
  2003年   71702篇
  2002年   69376篇
  2001年   108754篇
  2000年   111464篇
  1999年   93499篇
  1998年   26996篇
  1997年   23659篇
  1996年   24054篇
  1995年   22717篇
  1994年   20898篇
  1993年   19712篇
  1992年   72003篇
  1991年   70072篇
  1990年   68395篇
  1989年   65664篇
  1988年   60302篇
  1987年   59128篇
  1986年   55217篇
  1985年   53005篇
  1984年   39315篇
  1983年   33396篇
  1982年   19858篇
  1979年   35866篇
  1978年   25652篇
  1977年   21231篇
  1976年   20333篇
  1975年   21817篇
  1974年   26148篇
  1973年   24802篇
  1972年   23202篇
  1971年   22038篇
  1970年   20247篇
  1969年   19316篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
Many types of seafood require cooking before ingestion and it has been demonstrated that this cooking process may affect the antigenicity and allergenicity of the food. We describe a case of anaphylaxis caused by selective sensitization to razor shell, a mollusc. In vivo and in vitro studies confirmed sensitization to boiled razor shell. Analysis of the nature of the allergen yielded results that were consistent with the findings of other authors and suggested that allergens involved in seafood allergy are commonly high molecular weight proteins that, in most cases, are heat stable.  相似文献   
942.
943.
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   
944.
945.
946.
947.
948.
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   
949.
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   
950.
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