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   2391857篇
  免费   183050篇
  国内免费   4597篇
耳鼻咽喉   31753篇
儿科学   78858篇
妇产科学   68046篇
基础医学   348147篇
口腔科学   66116篇
临床医学   220379篇
内科学   468881篇
皮肤病学   53614篇
神经病学   195015篇
特种医学   89771篇
外国民族医学   702篇
外科学   347656篇
综合类   53644篇
现状与发展   4篇
一般理论   972篇
预防医学   193945篇
眼科学   54474篇
药学   171685篇
  8篇
中国医学   4908篇
肿瘤学   130926篇
  2019年   19213篇
  2018年   26514篇
  2017年   20262篇
  2016年   22599篇
  2015年   25538篇
  2014年   35950篇
  2013年   54303篇
  2012年   73613篇
  2011年   78501篇
  2010年   45971篇
  2009年   44024篇
  2008年   73208篇
  2007年   78004篇
  2006年   78021篇
  2005年   75971篇
  2004年   72943篇
  2003年   69661篇
  2002年   67460篇
  2001年   111899篇
  2000年   114248篇
  1999年   95396篇
  1998年   27160篇
  1997年   24648篇
  1996年   24974篇
  1995年   23689篇
  1994年   21773篇
  1993年   20370篇
  1992年   73851篇
  1991年   71706篇
  1990年   69074篇
  1989年   66527篇
  1988年   61331篇
  1987年   59975篇
  1986年   56572篇
  1985年   53757篇
  1984年   41013篇
  1983年   35280篇
  1982年   21192篇
  1981年   19188篇
  1979年   37645篇
  1978年   27196篇
  1977年   22658篇
  1976年   21216篇
  1975年   22325篇
  1974年   27126篇
  1973年   26463篇
  1972年   24950篇
  1971年   22986篇
  1970年   21727篇
  1969年   20360篇
排序方式: 共有10000条查询结果,搜索用时 4 毫秒
991.
Basal isolated canine paw blood flow was equally distributed between arteriovenous anastomosis (AVA) and capillary circulations. Norepinephrine decreased AVA flow by 92% and capillary flow by 41%. Dopamine significantly reduced AVA flow by 94% compared to baseline with a 37% reduction in capillary flow. However, with alpha-adrenergic blockade dopamine decreased AVA flow 66% while capillary flow increased 42%. Isoproterenol increased capillary flow almost twofold and appeared to decrease AVA flow, although the latter was statistically insignificant. Differential effects of adrenergic and dopaminergic agonists on canine paw AVA and capillary blood flow suggest the existence of independent regulation of these components of the microcirculation.  相似文献   
992.
Mitogen responsiveness of lymphocytes from the BB/W rat   总被引:3,自引:0,他引:3  
B A Woda  C Padden 《Diabetes》1986,35(5):513-516
The response of BB diabetes-prone (DP) and W-line non-diabetes-prone rats to the T-cell mitogen concanavalin A (ConA) was measured. The W line was a good responder to ConA, whereas the DP was relatively unresponsive. This unresponsiveness could not be reversed with exogenous interleukin 2 (IL-2). The response of DP rats was enhanced by removing adherent cells. To directly test the response of BB T-cells, they were isolated by flow sorting. These experiments demonstrated that BB T-cells could mount a normal ConA response. The normal function of isolated BB T-cells suggested that they were under suppression. Suppressor activity could not be found in the OX8+ population but was found in the DP-adherent cell population. Adherent cells from the W line were not suppressive at the concentrations used. These results showed that the decreased mitogen responsiveness of BB T-cells was not due to an intrinsic T-cell abnormality but was due, in part, to suppression by adherent cells.  相似文献   
993.
A case of cryptococcal meningoencephalitis, as presented by a hypertensive hydrocephalus, is described. To our knowledge, this is the 24th case described in Italy since 1953. The diagnosis was made with ventricular fluid examination: the patient was successfully treated with amphotericin B and 5-fluorocytosine, thus avoiding the risks of surgical treatment of hydrocephalus. Early diagnosis and proper therapy are necessary in order to decrease the high lethality of cryptococcosis.  相似文献   
994.
Priapism: a refined approach to diagnosis and treatment   总被引:4,自引:0,他引:4  
The recent introduction of intracorporeal injections of papaverine and phentolamine for the diagnosis and treatment of impotence has resulted in an increased incidence of iatrogenic priapism. Based on our research into penile hemodynamics we propose a refined approach to all types of priapism. Intracorporeal blood gas and pressure monitoring should be used to differentiate ischemic (low flow) from nonischemic (high flow) types. Most cases of papaverine-induced or phentolamine-induced priapism will respond to aspiration alone or in combination with intracorporeal instillation of a diluted alpha-adrenergic agent. In spontaneous priapism alpha-adrenergic agents can be tried first if patients have only mild or no ischemia. In patients with severe ischemia stagnant blood should be evacuated and a shunt procedure should be performed to allow metabolic replenishment of tissue. Intracorporeal pressure monitoring will help to determine the size and number of shunts needed to re-establish corporeal circulation.  相似文献   
995.
Osteomalacia and bone disease arising from aluminum   总被引:2,自引:0,他引:2  
  相似文献   
996.
997.
The pattern evoked electroretinogram (PERG) was investigated in 11 patients with unilateral optic nerve disease and in a series of age-matched controls. The visually evoked potential (VEP) was also measured. The PERG showed a similar reduction to the VEP in optic nerve disease. Serial studies indicate that the PERG may not be affected immediately in some instances but may show a gradual decline over several months.  相似文献   
998.
999.
1000.
IPEX (immunodysregulation, polyendocrinopathy, enteropathy, X linked syndrome) is a rare disorder which usually results in death in early infancy or childhood. Clinical awareness remains the cornerstone of diagnosis, and provided that the diagnosis is entertained, mutation analysis for FOXP3 gene mutations can be confirmatory. Two new patients in whom IPEX was diagnosed retrospectively are reported.  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