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   933639篇
  免费   66521篇
  国内免费   1345篇
耳鼻咽喉   12964篇
儿科学   24398篇
妇产科学   23289篇
基础医学   133153篇
口腔科学   28264篇
临床医学   80713篇
内科学   183501篇
皮肤病学   19256篇
神经病学   72337篇
特种医学   36937篇
外国民族医学   79篇
外科学   152418篇
综合类   18128篇
现状与发展   1篇
一般理论   248篇
预防医学   62026篇
眼科学   21325篇
药学   72582篇
  3篇
中国医学   2163篇
肿瘤学   57720篇
  2018年   9014篇
  2017年   7059篇
  2016年   7801篇
  2015年   8902篇
  2014年   12035篇
  2013年   17570篇
  2012年   24169篇
  2011年   25130篇
  2010年   14867篇
  2009年   14338篇
  2008年   24673篇
  2007年   25756篇
  2006年   26546篇
  2005年   25483篇
  2004年   24610篇
  2003年   23661篇
  2002年   23209篇
  2001年   54767篇
  2000年   56580篇
  1999年   46990篇
  1998年   10756篇
  1997年   9481篇
  1996年   9615篇
  1995年   8944篇
  1994年   8295篇
  1993年   7609篇
  1992年   35541篇
  1991年   33959篇
  1990年   32784篇
  1989年   31912篇
  1988年   29029篇
  1987年   28289篇
  1986年   26326篇
  1985年   25172篇
  1984年   17858篇
  1983年   15163篇
  1982年   7808篇
  1981年   6791篇
  1979年   15793篇
  1978年   10612篇
  1977年   9059篇
  1976年   7881篇
  1975年   8642篇
  1974年   10482篇
  1973年   9872篇
  1972年   9374篇
  1971年   8857篇
  1970年   8437篇
  1969年   7936篇
  1968年   7210篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Uniparental isodisomy (iUPD) is a rare genetic condition caused by non-disjunction during meiosis that ultimately leads to a duplication of either the maternal or paternal chromosome in the affected individual. Two types of disorders can result, those due to imprinted genes and those due to homozygosity of recessive disease-causing mutations. Here, we describe the third known case of complete chromosome 4 iUPD of maternal origin. This condition became apparent during whole genome linkage studies of psychiatric disorders in the Portuguese population. The proband is an adult female with normal fertility and no major medical complaints, but a history of major depressive disorder and multiple suicide attempts. The proband's siblings and parents had normal chromosome 4 genotypes and no history of mood disturbance. A brief review of other studies lends support for the possibility that genes on chromosome 4 might confer risk for mood disorders. We conclude that chromosome 4 maternal uniparental disomy (UPD) is a rare disorder that may present with a major depressive phenotype. The lack of a common disease phenotype between this and two other cases of chromosome 4 iUPD [Lindenbaum et al. [1991] Am J Med Genet 49(Suppl 285):1582; Spena et al. [2004] Eur J Hum Genet 12:891-898) would suggest that there is no vital maternal gene imprinting on chromosome 4. However, since there is no reported case of paternal chromosome 4 UPD, paternal gene imprinting on chromosome 4 cannot be excluded.  相似文献   
72.
In order to assess the state and pathology of the woman's pelvis minor, a number of methods are commonly used among practitioners, encompassing clinical exploration, radiology, MRN, urodynamics, endoscopy and echography.

Echography has been poorly used in clinical pelvic exploration and its reliability is actually a matter of controversy 1. However, echographic surveys can provide us with valuable gynecological data on the state and pathologies of the soft pelvis, within the genital regions or even going beyond them, i.e. the rectal channel, bladder, urethra, anus, vascular plexuses, and all of their supporting tissues.

At our research unit, we have been employing Transvaginal Ultrasound echography (TVU) for a long time in conjunction with other pelvis-focused methods in order to study different kinds of pelvic alterations. TVU has proven to be friendly to use, fast, harmless and inexpensive, allowing serial explorations and producing high-quality dynamic images (loop-cinema, video-tape). Furthermore, this method is fairly aseptic in that the occurrence of faeces in the rectal ampolla is not a nuisance but a bonus in tracking the contours of the rectum walls and other topographical features which would be otherwise difficult to survey.

A complete pelvic floor TVU may add no longer than 5-8 minutes to a routine gynecological examination, can be implemented by the general gynecologist and generates data that can be further studied by the appropriate specialist for a more insightful evaluation 2.  相似文献   
73.
74.
75.
76.
77.
78.
Ten years experience with acute peritoneal dialysis in 39 preterm-, newborn and small infants shows advantage and low risk of surgically implanted single dacron cuffed silicone catheters compared to trocar catheters.  相似文献   
79.
Computed tomography (CT) is currently the imaging modality of choice for assessing the morphology of the adrenal glands in adult patients. Much useful information can be gained using CT in disease processes which primarily involve one or both of the adrenal glands, such as adenomas, as well as in entities which secondarily affect the adrenals, such as pituitary or metastatic disease. The size and configuration of the glands can be readily determined, and masses may be detected. We discuss CT of normal and abnormal adrenal glands with sonographic (US) and pathological correlation, when available. Entities which may mimic adrenal abnormalities are emphasized. Relative advantages of US over CT in the pediatric patient are discussed.  相似文献   
80.
The Dundee Memory Clinic was established in 1991. This paper reviews the diagnosis of the first 150 attenders and compares the findings with those of other memory clinics.  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