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   14103篇
  免费   1209篇
  国内免费   43篇
耳鼻咽喉   98篇
儿科学   460篇
妇产科学   559篇
基础医学   1793篇
口腔科学   328篇
临床医学   1449篇
内科学   2796篇
皮肤病学   116篇
神经病学   1471篇
特种医学   502篇
外科学   2003篇
综合类   336篇
一般理论   26篇
预防医学   1418篇
眼科学   274篇
药学   879篇
中国医学   39篇
肿瘤学   808篇
  2021年   137篇
  2020年   92篇
  2019年   151篇
  2018年   153篇
  2017年   123篇
  2016年   144篇
  2015年   197篇
  2014年   244篇
  2013年   465篇
  2012年   607篇
  2011年   702篇
  2010年   391篇
  2009年   385篇
  2008年   697篇
  2007年   748篇
  2006年   781篇
  2005年   768篇
  2004年   765篇
  2003年   754篇
  2002年   754篇
  2001年   235篇
  2000年   256篇
  1999年   298篇
  1998年   217篇
  1997年   183篇
  1996年   164篇
  1995年   171篇
  1994年   132篇
  1993年   149篇
  1992年   257篇
  1991年   221篇
  1990年   197篇
  1989年   204篇
  1988年   225篇
  1987年   201篇
  1986年   194篇
  1985年   191篇
  1984年   201篇
  1983年   145篇
  1982年   172篇
  1981年   157篇
  1980年   143篇
  1979年   157篇
  1978年   146篇
  1977年   120篇
  1976年   89篇
  1975年   104篇
  1974年   120篇
  1973年   103篇
  1972年   86篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Cognitive Therapy and Research - Despite interest in psychological inflexibility as a marker of suicide risk, no measure of psychological inflexibility specific to SI exists. The present study...  相似文献   
2.
3.
4.
5.
6.
Anorectal function in the solitary rectal ulcer syndrome   总被引:8,自引:6,他引:2  
The anorectal function of nine patients with solitary rectal ulcer syndrome (SRUS) (5 F: 4 M, median age, 27 (range, 19–41 years) and nine control subjects (5 F: 4 M, median age, 47 (35–66)P<0.01) has been investigated by a new technique that radiologically visualizes the anorectum during voiding of a semisolid contrast medium, while simultaneously measuring intrarectal pressure and anal sphincter EMG activity. A degree of rectal prolapse was demonstrated in eight of the SRUS patients; six of these lesions were clinically occult. Abnormal failure of the anal sphincter to relax on voiding was present in seven of the SRUS patients. These abnormalities resulted in the SRUS patients requiring a greater increase in intrarectal pressure (median, 100 cm water) to void than the control subjects (median, 65 cm water,P<0.01). This combination of high intrarectal pressure and rectal prolapse during straining seems to be the cause of SRUS This work was supported by a grant from the Medical Research Council.  相似文献   
7.
1. Twenty-two patients hospitalized for treatment of depression were treated under conditions simulating those of home treatment. 2. Full doses of nortriptyline, from 100 to 150 mg/day, were started after baseline observations were made. 3. Two patients were dropped from the study, one for orthostatic hypotension, one for an aberrant response to nortriptyline. Two additional patients developed orthostasis which was easily managed. Otherwise no unusual side effects were noted. 4. After six days of treatment, 9 of 20 patients showed significant improvement with an overall reduction in scores on the Hamilton Depression Scale of 49% for the entire group. 5. Using the weight-adjusted dosage schedule, 18 of the 21 patients attained plasma concentrations of nortriptyline within the presumed therapeutic range; however, no clear relationship could be established between plasma concentrations and clinical response. 6. With proper selection of patients, it should be possible to treat at home some patients who currently are considered to require hospitalization.  相似文献   
8.
Cerebral dysgenesis encompasses varied disorders of brain development. Based on the understanding of these conditions provided by histopathologists, embryologists, radiologists and developmental pediatricians, surgeons are able to appropriately assist in the care of these patients. The surgeon can offer assessment of the ventriculomegaly that commonly accompanies cerebral dysgenesis in addition to providing methods to control hydrocephalus, to reconstruct cranial and facial malformations and to remove dysfunctional tissue. For most patients, surgical intervention is only one of the many factors that determine developmental prognosis. Based on the foundation built by other specialists, this review discusses cerebral dysgenesis from the perspective of historical and current surgical interventions.  相似文献   
9.
A flow-through finite-dose diffusion cell has been designed for use in transdermal drug delivery research. The diffusion cell consists of an upper donor chamber and a lower receiver compartment through which a continuous supply of fresh solvent flows. The flow is directed to an automatic fraction collector. To validate the flow-through cell, its performance was compared directly against that of a conventional single-reservoir Franz cell. Homologous alkyl p-aminobenzoates were diffused through dimethylpolysiloxane membranes, and permeability coefficients increased with increasing chain length, reaching a plateau at the butyrate ester for both types of cells. This behavior suggests a shift from membrane-controlled diffusion to boundary layer control. Permeation of the butyrate and valerate compounds was significantly faster when the flow-through cell was used, suggesting that better mixing is obtained through the flow-through cell design. Considering the advantages offered in terms of time and labor saved through its use, the flow-through cell with automatic fraction collector appears to be a viable alternative to the conventional Franz cell.  相似文献   
10.
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