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   13688篇
  免费   2831篇
  国内免费   133篇
耳鼻咽喉   437篇
儿科学   339篇
妇产科学   370篇
基础医学   698篇
口腔科学   228篇
临床医学   3461篇
内科学   2484篇
皮肤病学   339篇
神经病学   1135篇
特种医学   491篇
外科学   1844篇
综合类   416篇
现状与发展   2篇
一般理论   5篇
预防医学   2365篇
眼科学   174篇
药学   529篇
  1篇
中国医学   103篇
肿瘤学   1231篇
  2024年   85篇
  2023年   453篇
  2022年   182篇
  2021年   389篇
  2020年   585篇
  2019年   305篇
  2018年   730篇
  2017年   712篇
  2016年   748篇
  2015年   845篇
  2014年   882篇
  2013年   1348篇
  2012年   756篇
  2011年   662篇
  2010年   713篇
  2009年   789篇
  2008年   574篇
  2007年   481篇
  2006年   505篇
  2005年   365篇
  2004年   332篇
  2003年   301篇
  2002年   240篇
  2001年   254篇
  2000年   192篇
  1999年   203篇
  1998年   303篇
  1997年   310篇
  1996年   334篇
  1995年   264篇
  1994年   196篇
  1993年   144篇
  1992年   139篇
  1991年   129篇
  1990年   111篇
  1989年   129篇
  1988年   101篇
  1987年   96篇
  1986年   88篇
  1985年   94篇
  1984年   80篇
  1983年   69篇
  1982年   51篇
  1981年   59篇
  1980年   39篇
  1979年   34篇
  1978年   35篇
  1977年   31篇
  1976年   25篇
  1975年   16篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
22.
The new complaints procedures which local authority social services departments have been required to introduce represent an important mechanism for managing the change of culture associated with recent community care reforms. They also represent a new genre in mechanisms of redress for welfare recipients. This paper reports the findings of a study which has observed considerable diversity in the ways in which local authorities are interpreting the nature and purposes of the new procedures and, in particular, the functions of review panels established under those procedures. Variations in the composition of panels, in the style of review panel proceedings, in perceptions of the panels' powers, and in the ways that complaints and complainants are constituted are all discussed. Attention is drawn to four competing interpretations of the review panels' role and to the need for these to be clarified and prioritised.  相似文献   
23.
Eight normotensive subjects received single and multiple doses of cromakalim (1 mg) and placebo in a randomised double-blind cross-over study to examine general tolerance to cromakalim and its effects on blood pressure (BP), heart rate (HR), and pressor responses to norepinephrine (NE) and angiotensin II (AII). In a second study, 10 hypertensive patients whose BP control was unsatisfactory with atenolol 50-100 mg received additional treatment with placebo followed by cromakalim 1 mg daily for 4 weeks. Assessments were made of BP, HR, apparent hepatic blood flow and renal blood flow (RBF), pulmonary function, and the pharmacokinetics of atenolol. Cromakalim was generally well tolerated in both normotensive and hypertensive subjects. In the normotensive group, cromakalim produced a reflex increase in HR without any detectable decrease in BP: average (placebo-subtracted) increases in HR at 4 h were 16 beats/min with subjects in an erect position after the single dose and 14 beats/min after 7 days. Cromakalim had no effect on pressor responses to NE and AII. Addition of cromakalim to atenolol was associated with modest further reductions in BP between 0.5 and 3 h after drug administration, with maximal reductions of 21/14 mm Hg (subjects in supine position) 2 h after the first dose. Cromakalim had no effect on apparent liver blood flow and RBF, pulmonary function, and the steady-state pharmacokinetics of atenolol. Single and multiple 1-mg doses of cromakalim are well tolerated but are associated with only modest vasodilator activity.  相似文献   
24.
25.
26.
Background and Objectives: The perception of pain is a personal experience influenced by many factors, including genetic, ethnic and cultural issues. Understanding these perceptions is especially important in dermatologic patients undergoing minor surgical operations and who often differ in their pain response to surgical treatments. Little is known about how these differences affect the perception of experimental pain. The purpose of this study was to determine experimental pain perception differences in three distinct East Asian ethnic populations.
Methods: Pain thresholds were examined with a psychophysical computerized quantitative thermal sensory testing device (TSA 2001) in healthy volunteers recruited from three different Asian ethnic groups. Using the methods of limits, experimental pain perception threshold was measured on the forehead and volar aspect of the forearm in 49 healthy subjects. The measurements were then repeated after skin barrier perturbation with adhesive tape stripping of the stratum corneum. All three ethnic groups were analyzed separately with respect to age, gender educational level and skin type.
Results: A total of 20 Chinese, 14 Malay and 15 Indian subjects completed the study. Thermal pain thresholds were similar in all three ethnic groups before and after tape strippings. No significant differences were noted between genders.
Conclusions: Using quantitative sensory thermal testing, we demonstrated that no significant differences in pain occur between different races and genders.  相似文献   
27.
Furan is a liver carcinogen and toxicant. Furan is oxidized to the reactive dialdehyde, cis-2-butene-1,4-dial, by microsomal enzymes. This reactive metabolite readily reacts with glutathione nonenzymatically to form conjugates. A high-performance liquid chromatography-electrochemical method for the detection of cis-2-butene-1,4-dial-glutathione (GSH) conjugates in microsomal preparations was developed to measure the extent of furan metabolism to cis-2-butene-1,4-dial in vitro. Previously unobserved mono-GSH reaction products of cis-2-butene-1,4-dial were detected in addition to the already characterized bis-GSH conjugates. Chemical characterization of these compounds indicated that the alpha-amino group of glutathione had reacted with cis-2-butene-1,4-dial to form a thiol-substituted pyrrole adduct. The analytical method was used to estimate the extent of furan oxidation in rat liver microsomes from untreated or acetone-pretreated F344 rats as well as in human P450 2E1 Supersomes. Our results confirm that cytochrome P450 2E1 can catalyze the oxidation of furan to cis-2-butene-1,4-dial. However, the data are also consistent with the involvement of other P450 enzymes in the oxidation of furan in untreated animals. This assay will be a valuable tool to explore tissue and species differences in rates of furan oxidation.  相似文献   
28.
29.
30.
Noninsulin dependent diabetes (type II diabetes) is a chronic disease characterized by hyperglycemia. Clients can generally be controlled by diet and exercise or a combination of diet, exercise, and oral hypoglycemic agents. When this therapy is not effective in controlling the hyperglycemia, the health care provider must choose to initiate insulin therapy. Outpatient initiation of insulin is an alternative to hospitalization in the type II diabetic client. Clinical guidelines for the initiation of insulin on an outpatient basis and management of the diabetic client are presented.  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