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   478篇
  免费   102篇
  国内免费   3篇
耳鼻咽喉   1篇
儿科学   2篇
妇产科学   9篇
基础医学   81篇
口腔科学   1篇
临床医学   43篇
内科学   144篇
皮肤病学   13篇
神经病学   46篇
特种医学   6篇
外国民族医学   3篇
外科学   58篇
综合类   24篇
预防医学   57篇
眼科学   2篇
药学   22篇
肿瘤学   71篇
  2021年   5篇
  2014年   8篇
  2013年   6篇
  2012年   22篇
  2011年   22篇
  2010年   7篇
  2009年   13篇
  2008年   18篇
  2007年   25篇
  2006年   23篇
  2005年   26篇
  2004年   15篇
  2003年   34篇
  2002年   6篇
  2001年   21篇
  2000年   8篇
  1999年   8篇
  1998年   8篇
  1997年   4篇
  1996年   9篇
  1995年   4篇
  1994年   10篇
  1993年   12篇
  1992年   14篇
  1991年   19篇
  1990年   9篇
  1989年   9篇
  1988年   11篇
  1987年   6篇
  1986年   7篇
  1985年   17篇
  1984年   13篇
  1983年   15篇
  1982年   10篇
  1981年   8篇
  1980年   5篇
  1979年   7篇
  1978年   5篇
  1977年   4篇
  1976年   10篇
  1975年   8篇
  1974年   7篇
  1973年   11篇
  1972年   4篇
  1971年   7篇
  1970年   13篇
  1969年   5篇
  1968年   7篇
  1967年   9篇
  1966年   4篇
排序方式: 共有583条查询结果,搜索用时 31 毫秒
81.
Mortality in acromegaly   总被引:9,自引:0,他引:9  
  相似文献   
82.
Approximately 50% of depressed patients are resistant to the cortisol-suppressing effect of dexamethasone. To determine if glucocorticoid resistance could be a more generalized phenomenon in depressed patients, mitogen stimulation tests were performed on lymphocytes from 12 depressed patients and 12 control subjects before and after dexamethasone administration. Suppression of serum cortisol following administration of 1 mg of dexamethasone in four depressed patients and 11 control subjects was associated with a decreased lymphoproliferative response, but no such change occurred in the eight depressed patients and the single control subject who did not suppress cortisol. The dexamethasone-induced changes in the mitogen responses were positively correlated with the highest postdexamethasone serum cortisol values.  相似文献   
83.
84.
An hallucinogen analogue, trans-2-(2,5-dimethoxy-4-methylphenyl)cyclopropylamine (DMCPA), was resolved into ints two enantiomers by fractional crystallization of salts with d- or l-O,O-dibenzoyltartaric acid. A comparison of the ORD and CD curves of the N-5-bromosalicylidene derivatives of trans-2-phenylcyclopropylamine of known absolute configuration and of the title compound established the stereochemistry of the latter to be (1R,2S)-(-) and (1s,2r)-(+). We have earlier shown that the (-) isomer shows selective behavioral effects in cats and mice. In present study it was found that the (-) isomer selectively elicits rabbit hyperthermia when compared with the (+) isomer. In view of the stereoselective ability of the (-) isomer to elicit hallucinogen-like behavioral profiles in these animal models, the proof of absolute configuration lends further support to a new model which interrelates the active binding, conformation of phenethylamine hallucinogens to that of serotonin and tryptamines.  相似文献   
85.
86.
87.
88.
89.
BACKGROUND: Past studies have identified surgeon- and institution- related characteristics as prognostic factors in colorectal cancer surgery. The present work assesses the influence of the surgeon's and the hospital's caseload on long-term results of colorectal cancer surgery. METHODS: The data on 2706 patients from 2, randomized, colorectal cancer trials (Swiss Group for Clinical Cancer Research [SAKK] 40/81, SAKK 40/87) investigating adjuvant intraportal and systemic chemotherapy and 1 concurrent registration study (SAKK 40/88) were reviewed. A first analysis included 1809 eligible, nonmetastatic patients from all 3 studies. A subsequent subgroup analysis included 915 eligible patients from both randomized trials. Overall survival (OS), disease-free survival (DFS), and local recurrence (LR) were analyzed in multivariate models taking into account the possible effect of clustering. The main potential covariates were surgeon's annual caseload (>5 operations/year vs < or =5 operations/year), hospital's annual caseload (>26 operations/year vs < or =26 operations/year), tumor site, T stage, and nodal status. RESULTS: Primary analysis of all 3 studies combined found a high surgeon's caseload to be positively associated with OS (P = .025) and marginally with DFS (P = .058). Separate analysis for each trial, however, showed that a high surgeon's caseload was beneficial for outcome in both randomized trials but not in the registration study. A subgroup analysis of 915 patients with 376 rectal and 539 colonic primaries from both randomized trials, therefore, was performed. Neither age, gender, year of operation, adjuvant chemotherapy (intraportal vs systemic vs operation alone), hospital academic status (university vs non-university), training status of the surgeon (certified surgeon vs surgeon-in-training), nor inclusion in 1 of the 2 randomized trials (SAKK 40/81 vs SAKK 40/87) was a significant predictor of outcome. However, both high surgeon's and high hospital's annual caseloads were independent, beneficial prognostic factors for OS (P = .0003, P = .044) and DFS (P = .0008, P = .020), and marginally significant factors for LR (P = .057, P = .055). CONCLUSIONS: High surgeon's and hospital's annual caseloads are strong, independent prognostic factors for extending overall and disease-free survival and reducing the rate of local recurrence in 2 randomized colorectal cancer trials.  相似文献   
90.
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