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   1086篇
  免费   69篇
  国内免费   34篇
耳鼻咽喉   2篇
儿科学   47篇
妇产科学   12篇
基础医学   139篇
口腔科学   28篇
临床医学   128篇
内科学   185篇
皮肤病学   18篇
神经病学   68篇
特种医学   123篇
外科学   84篇
综合类   16篇
预防医学   166篇
眼科学   8篇
药学   132篇
中国医学   2篇
肿瘤学   31篇
  2021年   16篇
  2020年   8篇
  2019年   9篇
  2018年   16篇
  2016年   13篇
  2015年   20篇
  2014年   32篇
  2013年   40篇
  2012年   36篇
  2011年   40篇
  2010年   34篇
  2009年   43篇
  2008年   25篇
  2007年   41篇
  2006年   22篇
  2005年   26篇
  2004年   26篇
  2003年   26篇
  2002年   32篇
  2001年   18篇
  2000年   22篇
  1999年   33篇
  1998年   35篇
  1997年   42篇
  1996年   41篇
  1995年   26篇
  1994年   37篇
  1993年   24篇
  1992年   15篇
  1991年   20篇
  1990年   20篇
  1989年   30篇
  1988年   28篇
  1987年   23篇
  1986年   23篇
  1985年   12篇
  1984年   15篇
  1983年   14篇
  1982年   17篇
  1981年   15篇
  1980年   13篇
  1976年   11篇
  1975年   8篇
  1974年   7篇
  1924年   6篇
  1911年   9篇
  1910年   8篇
  1909年   7篇
  1908年   7篇
  1907年   6篇
排序方式: 共有1189条查询结果,搜索用时 31 毫秒
1.
Kim  SH; Chang  KH; Song  IC; Han  MH; Kim  HC; Kang  HS; Han  MC 《Radiology》1997,204(1):239
  相似文献   
2.
3.
4.
5.
A series of alkyl- and halo-substituted 8-(1-piperazinyl)imidazo[1,2-a]pyrazines were prepared using two approaches, the condensation of alpha-halocarbonyl derivatives with an aminopyrazine or the oxidation-dehydration of a [(beta-hydroxyalkyl)amino]pyrazine. These imidazo[1,2-a]pyrazines were evaluated for their binding affinity to the alpha 1, alpha 2, beta 1, and beta 2 adrenergic receptors as well as their ability to lower blood glucose in insulin resistant hyperglycemic ob/ob mice. Modifications on 8-(1-piperazinyl)imidazo[1,2-a]pyrazine (4) reduced alpha 2 binding, lowered hypoglycemic potency, and showed variations in binding to the alpha 1, beta 1, and beta 2 adrenergic receptors. In addition to 4, the 2-methyl, 3-methyl, and 5-methyl 8-(1-piperazinyl)imidazo[1,2-a]pyrazines (16k, 25m, and 16f, respectively) displayed high affinity for the alpha 2 receptor and were potent hypoglycemic agents when compared to 2-amino-7,8-dihydro-4-(1-piperazinyl)-6H-thiopyrano[3,2- d]pyrimidine (MTP-1403, 2). Receptor binding was modified by use of a 4-methylpiperazine moiety which reduced alpha 1 and beta 1 binding while retaining some hypoglycemic activity. The structure-activity relationship for heterocyclic alkyl and halo substitution on biological activity is discussed.  相似文献   
6.
We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder.  相似文献   
7.
8.
Access to pregnancy-related care for women and their infants and to reproductive health services for adolescents are significant concerns to the American College of Obstetricians and Gynecologists (ACOG). Adolescent and young adult women are among those most likely to be uninsured and lack access to health care services. Adolescent pregnancy, low-birth weight, and infant mortality remain major national burdens. The ACOG has taken the position that quality health care should be accessible to all women. The ACOG recommendations regarding health services for adolescents and the ACOG Committee on Health Care for Underserved Women's statement of principles regarding universal access for pregnancy-related care, which includes the basic scope of benefits, the characteristics of the providers, and the organization of services are described.  相似文献   
9.
Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture.  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