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   656篇
  免费   12篇
  国内免费   1篇
耳鼻咽喉   6篇
儿科学   19篇
妇产科学   11篇
基础医学   51篇
口腔科学   40篇
临床医学   43篇
内科学   101篇
皮肤病学   4篇
神经病学   14篇
特种医学   83篇
外科学   129篇
综合类   42篇
预防医学   33篇
眼科学   10篇
药学   54篇
  1篇
中国医学   1篇
肿瘤学   27篇
  2023年   4篇
  2022年   7篇
  2021年   7篇
  2020年   9篇
  2019年   10篇
  2018年   10篇
  2017年   6篇
  2016年   8篇
  2015年   10篇
  2014年   13篇
  2013年   20篇
  2012年   25篇
  2011年   33篇
  2010年   22篇
  2009年   28篇
  2008年   32篇
  2007年   36篇
  2006年   39篇
  2005年   35篇
  2004年   27篇
  2003年   21篇
  2002年   15篇
  2001年   20篇
  2000年   22篇
  1999年   14篇
  1998年   11篇
  1997年   20篇
  1996年   15篇
  1995年   10篇
  1994年   13篇
  1993年   13篇
  1992年   12篇
  1991年   9篇
  1990年   7篇
  1989年   17篇
  1988年   8篇
  1987年   8篇
  1986年   4篇
  1985年   7篇
  1984年   6篇
  1983年   5篇
  1981年   5篇
  1980年   7篇
  1979年   7篇
  1978年   4篇
  1977年   3篇
  1976年   3篇
  1974年   1篇
  1970年   1篇
排序方式: 共有669条查询结果,搜索用时 0 毫秒
101.
Mosquitoes of 26 species belonging to 16 subgenera and 11 genera were recorded in the Kundapur mangroves of Karnataka, and 17 species belonging to 11 subgenera and 7 genera were recorded in the mangroves of Kannur, Kerala along the west coast of India. Genera recorded were Aedes, Anopheles, Armigeres, Culex, Heizmannia, Lutzia, Mansonia, Ochlerotatus, Tripteroides, Uranotaenia, and Verrallina. Species common to both mangrove forests were Ae. albopictus, Ae. vittatus, An. jamesi, Ar. subalbatus, Cx. gelidus, Cx. infantulus, Cx. pseudovishnui, Cx. sitiens, Cx. tritaeniorhynchus, Oc. wardi, Ur. atra, and Ve. luguhris. Tree holes and swamp pools were the common larval habitats, with more species occurring in tree holes in Kundapur than in Kannur. Adults of Ae. albopictus, Ae. vittatus, Ar. aureolineatus, Ar. subalbatus, Cx. bitaeniorhynchus, Cx. sitiens, Ma. uniformis, and Ve. lugubris bloodfed on humans.  相似文献   
102.
Acute myocardial infarction is a rare form of presentation in patients with left atrial myxoma. With wider availability of echocardiography, more and more patients with atrial myxomas will be diagnosed. This report describes a patient with left atrial myxoma who presented features of acute myocardial infarction and had surgical removal of LA myxoma.  相似文献   
103.
104.
105.
Of 51 patients with detrusor-sphincter dyssynergia undergoing external urethral spincterotomy by transurethral resection, histological examination revealed no skeletal muscle in the resected tissue in six patients. The functional improvement which resulted in these cases despite this finding with an explanation for the same forms the topic of this paper.  相似文献   
106.
The predictive value of a recently developed physical model was tested in the topical treatment of cutaneous infections caused by herpes simplex virus type 1 in hairless mice with two ester prodrugs of 9-beta-D-arabinofuranosyladenine (ara-A) (1). The tests were conducted with 2',3'-di-O-acetyl-ara-A (4) and 5'-O-valeryl-ara-A (3) topically applied with and without 15% 1-dodecylazacycloheptan-2-one (2) (Azone), a percutaneous penetration enhancer. In addition to the in vivo studies, in vitro diffusion cell experiments with excised, full-thickness skin from hairless mice were conducted to determine the penetration enhancement effects of 2. As previously observed, 2 was able to induce remarkably large (100- to 1000-fold) flux enhancements in these in vitro experiments. Consistent with predictions based on the physical model studies, formulations of 3 and 4 without 2 had little or no influence on the pathogenesis of the herpes simplex virus type 1 infections; when 2 was present in the formulations, both 3 and 4 had dramatic therapeutic effects consistent with the predictions made with the physical model. Prodrug 4 with 2 was especially efficacious in the prevention of virus-induced lesions and in the survival of all animals. Similar results were obtained with acyclovir plus 2 in this model system.  相似文献   
107.
108.
Current initiatives such as the National Institute of Mental Health's Research Domain Criteria project aim to reorganize classification of mental disorders along neurobiological lines. Here, we describe how consideration of findings from psychiatric research employing two physiological measures with distinct neural substrates--the startle blink reflex and the error-related negativity (ERN)--can help to clarify relations among disorders entailing salient anxiety or depressive symptomatology. Specifically, findings across various studies and reviews reveal distinct patterns of association for both the startle blink reflex and the ERN with three key domains of psychopathology: (1) Fear (or phobic) disorders (distinguished by increased startle to unpleasant stimuli, but normal-range ERN). (2) Non-phobic anxiety disorders and negative affect (associated with increased ERN, increased startle across all types of emotional stimuli and increased baseline startle) and, more tentatively (3) Major depression (for which patterns of response for both startle and ERN appear to vary, as a function of severity and distinct symptomatology). Findings from this review point to distinct neurobiological indicators of key psychopathology domains that have been previously demarcated using personality and diagnostic data. Notably, these indicators exhibit more specificity in their relations with these three domains than has been seen in quantitative-dimensional models. Implications of these findings are discussed.  相似文献   
109.
110.
PURPOSE: The purpose of this in vitro study was to evaluate the: (1) shear bond strength (SBS) of acetone and ethanol-based bonding agents to composite resin 24 hours after being bleached with 35% hydrogen peroxide; and (2) interface morphology and mode of fracture (IMMF) between composite resin and enamel. METHODS: Forty extracted teeth were randomly assigned into 4 groups: (1) group 1: 35% H2O2 + acetone; (2) group 2: H2O2 + ethanol; (3) group 3: acetone; (4) group 4: ethanol. All teeth were acid etched, bonding agents were applied, and a composite resin stub was bonded and stored again in saline for 24 hours. SBS was determined, and scanning electron microscopy (SEM) was used for IMMF evaluation. RESULTS: SBS was significantly lower in bleached than unbleached teeth (P < .001), but SBS did not differ between the acetone-based or ethanol-based adhesives (P = .55) and bleaching did not interact with adhesive treatment (P = .39). IMMF analysis of the unbleached teeth showed a continuous interface between the resin and enamel. By contrast, bleached teeth showed sparse contact between the resin and enamel and the resin was poorly infiltrated into the enamel surface. CONCLUSION: Morphologic changes in human tooth enamel, 24 hours after bleaching, were associated with a reduction in the shear bond strength of adhesives.  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