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   3293篇
  免费   272篇
  国内免费   14篇
耳鼻咽喉   44篇
儿科学   99篇
妇产科学   74篇
基础医学   432篇
口腔科学   84篇
临床医学   245篇
内科学   607篇
皮肤病学   93篇
神经病学   345篇
特种医学   100篇
外科学   481篇
综合类   94篇
一般理论   3篇
预防医学   268篇
眼科学   110篇
药学   263篇
中国医学   22篇
肿瘤学   215篇
  2023年   40篇
  2022年   75篇
  2021年   170篇
  2020年   106篇
  2019年   103篇
  2018年   147篇
  2017年   86篇
  2016年   81篇
  2015年   101篇
  2014年   114篇
  2013年   149篇
  2012年   223篇
  2011年   259篇
  2010年   129篇
  2009年   100篇
  2008年   182篇
  2007年   198篇
  2006年   168篇
  2005年   125篇
  2004年   133篇
  2003年   105篇
  2002年   99篇
  2001年   64篇
  2000年   67篇
  1999年   47篇
  1998年   20篇
  1997年   12篇
  1996年   17篇
  1995年   21篇
  1994年   12篇
  1993年   12篇
  1992年   32篇
  1991年   47篇
  1990年   42篇
  1989年   32篇
  1988年   33篇
  1987年   32篇
  1986年   24篇
  1985年   19篇
  1984年   19篇
  1983年   9篇
  1981年   9篇
  1980年   10篇
  1979年   9篇
  1978年   9篇
  1977年   11篇
  1976年   7篇
  1975年   8篇
  1970年   7篇
  1968年   7篇
排序方式: 共有3579条查询结果,搜索用时 343 毫秒
21.
Quality control in cervical cytology   总被引:2,自引:1,他引:2       下载免费PDF全文
From surveys conducted by the authors it is concluded that the best and most acceptable quality control methods in cytology are those from within the laboratory. Most of these have results which can be reported centrally. Where the overall control and codes of practice are high, there the results are the most reliable, as sources of error from whatever cause are quickly brought to light. These conclusions are illustrated by data from the five centres and correlated in the tables.  相似文献   
22.
23.
The M2 receptor (M2-mAChR) is quantitatively the dominant muscarinic subtype in animal bladders. The alterations in its protein quantity and biosynthesis during diabetic cystopathy were investigated. Three-month-old male Wistar rats were divided into two groups: (1) 2-week-old diabetics; and (2) normoglycemic control rats. Diabetes was induced by single intravenous injection of 60 mg/kg streptozotocin. The amount of M2 receptor protein in the rat bladder body tissue was measured by Western immunoblotting using monoclonal antibodies. For determination of M2 muscarinic receptor mRNA in the bladder tissue, the method of Northern blotting was employed. The results of the Western immunoblotting showed that the amount of M2-mAChR protein in the diabetic bladder was significantly increased by 40.0 +/- 6.2% when compared with the control bladder (P < 0.05, n = 8). The Northern blotting demonstrated a 69.3 +/- 8.5% increase of the M2-mAChR mRNA in the diabetic bladder (P < 0.05, n = 8). The findings of the present study demonstrated an up-regulation of M2-mAChR biosynthesis in the diabetic urinary bladder. This phenomenon could lead to increased reactivity to acetylcholine and thus results in detrusor instability.  相似文献   
24.
25.
26.
The interaction of race and climatic adaptation on patterns of cardiovascular reactivity among young adult males was examined. Malay and Chinese subjects living in a tropical climate in the Orient and Caucasians living in a sub-tropical climate in North America were investigated. The cold pressor test with hand immersion in cold water was used as the stressor. Systolic and diastolic blood pressures, cardiac frequency, cardiac output, and stroke volume were measured. The results provided limited evidence for absence of differences in cardiac reactivity among racial groups and for greater vascular reactivity in the Caucasians. Cold immersion also elicited differential responses which could be partially attributed to differences in acclimatizations status. © 1995 Wiley-Liss, Inc.  相似文献   
27.
BACKGROUND: The high prevalence of depression in developing countries is not well understood. This study aimed to replicate the previous finding of a high prevalence of depression in Pakistan and assess in detail the associated social difficulties. METHOD: A two-phase survey of a general population sample in a Pakistani village was performed. The first-phase screen used the Personal Health Questionnaire (PHQ) and the self-rating questionnaire (SRQ). A one in two sample of high scorers and a one in three sample of the low scorers were interviewed using the Psychiatric Assessment Schedule (PAS) and Life Events and Difficulties Schedule (LEDS). RESULTS: A total of 259 people were screened (96% response rate). The second stage yielded 55 cases, of whom 54 had depressive disorder, and 48 non-cases. The adjusted prevalence of depressive disorders was 44-4% (95% CI 35.3 to 53.6): 25.5% in males and 57.5% in females. Nearly all cases had lasted longer than 1 year. Comparison of the cases and non-cases indicated that cases were less well educated, had more children and experienced more marked, independent chronic difficulties. Multivariate analysis indicated that severe financial and housing difficulties, large number of children and low educational level were particularly closely associated with depression. CONCLUSION: This study confirms the high prevalence of depressive disorders in Pakistan and suggests that this may be higher than other developing countries because of the high proportion of the population who experience social adversity.  相似文献   
28.
29.
Pure gonadal dysgenesis or Swyer syndrome is a sex-reversal disorder resulting from embryonic testicular regression sequences especially during the first few weeks of fetal life and is induced by mutations in the SRY gene. In the present report, we describe a nonmosaic XY sex-reversed female with pure gonadal dysgenesis. Molecular analysis using sequential PCR to detect Y chromosomal microdeletions showed the presence of SRY, ZFY and AZFa, b and c regions. Automated sequencing of the SRY region revealed a new mutation (deletion of A (adenine) in codon 82 at position +244), leading to a frame shift mutation within the helix I of the HMG-box domain. This mutation generates a truncated protein and is very likely to produce an impairment of SRY DNA binding activity. The present findings further support the functional importance of the putative DNA binding activity of the SRY HMG-box domain.  相似文献   
30.
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