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   59854篇
  免费   5054篇
  国内免费   126篇
耳鼻咽喉   563篇
儿科学   2127篇
妇产科学   1592篇
基础医学   7746篇
口腔科学   680篇
临床医学   7534篇
内科学   10748篇
皮肤病学   1129篇
神经病学   6116篇
特种医学   1333篇
外国民族医学   1篇
外科学   6773篇
综合类   578篇
现状与发展   1篇
一般理论   92篇
预防医学   8105篇
眼科学   1033篇
药学   4168篇
中国医学   75篇
肿瘤学   4640篇
  2023年   552篇
  2022年   894篇
  2021年   1986篇
  2020年   1195篇
  2019年   1943篇
  2018年   2070篇
  2017年   1608篇
  2016年   1696篇
  2015年   1819篇
  2014年   2554篇
  2013年   3351篇
  2012年   5029篇
  2011年   4912篇
  2010年   2645篇
  2009年   2257篇
  2008年   3952篇
  2007年   3861篇
  2006年   3636篇
  2005年   3444篇
  2004年   3010篇
  2003年   2556篇
  2002年   2250篇
  2001年   563篇
  2000年   521篇
  1999年   546篇
  1998年   419篇
  1997年   334篇
  1996年   285篇
  1995年   249篇
  1994年   216篇
  1993年   180篇
  1992年   321篇
  1991年   273篇
  1990年   299篇
  1989年   300篇
  1988年   257篇
  1987年   238篇
  1986年   230篇
  1985年   240篇
  1984年   204篇
  1983年   172篇
  1982年   132篇
  1981年   115篇
  1980年   110篇
  1979年   154篇
  1978年   142篇
  1977年   109篇
  1976年   107篇
  1974年   106篇
  1973年   124篇
排序方式: 共有10000条查询结果,搜索用时 18 毫秒
61.
62.
63.
64.
Abstract:  The risks of developing malignant melanoma (MM) include ultraviolet irradiation and genetic factors. To examine the contribution of rare and common variation within known MM genes in sporadic US MM patients, coding regions of known MM susceptibility genes [cyclin-dependent kinase inhibitor 2A ( CDKN2A ), cyclin-dependent kinase 4, melanocortin 1 receptor ( MC1R ) and tyrosinase ( TYR )] were resequenced in 109–135 MM cases. The significance of variants was examined by comparing their frequencies in 390 cancer-free controls. Potential deleterious mutations in CDKN2A were found in two patients and two others had variants of unknown significance. Cases were more likely than controls to harbour the MC1R 'R' variants known or predicted to alter its function ( P  = 0.002), particularly the R160W variant ( P  = 0.0035). The associated TYR R402Q variant (rs1126809*A) was found in 29% of cases, similar to what has been described previously. One MM patient with a family history of MM, who had developed other skin cancers, was homozygous for a novel TYR variant (P406L) of unknown significance. Hence, rare variants in TYR may be important risk factors for skin cancer.  相似文献   
65.
66.
ObjectiveWe examine remission rate probabilities, recovery rates, and residual symptoms across 36 weeks in the Treatment for Adolescents with Depression Study (TADS).MethodThe TADS, a multisite clinical trial, randomized 439 adolescents with major depressive disorder to 12 weeks of treatment with fluoxetine, cognitive–behavioral therapy, their combination, or pill placebo. The pill placebo group, treated openly after week 12, was not included in the subsequent analyses. Treatment differences in remission rates and probabilities of remission over time are compared. Recovery rates in remitters at weeks 12 (acute phase remitters) and 18 (continuation phase remitters) are summarized. We also examined whether residual symptoms at the end of 12 weeks of acute treatment predicted later remission.ResultsAt week 36, the estimated remission rates for intention-to-treat cases were as follows: combination, 60%; fluoxetine, 55%; cognitive–behavioral therapy, 64%; and overall, 60%. Paired comparisons reveal that, at week 24, all active treatments converge on remission outcomes. The recovery rate at week 36 was 65% for acute phase remitters and 71% for continuation phase remitters, with no significant between-treatment differences in recovery rates. Residual symptoms at the end of acute treatment predicted failure to achieve remission at weeks 18 and 36.ConclusionsMost depressed adolescents in all three treatment modalities achieved remission at the end of 9 months of treatment.  相似文献   
67.
Contrary to popular beliefs, a recent empirical study using eye tracking has shown that a non-clinical sample of socially anxious adults did not avoid the eyes during face scanning. Using eye-tracking measures, we sought to extend these findings by examining the relation between stable shyness and face scanning patterns in a non-clinical sample of 11-year-old children. We found that shyness was associated with longer dwell time to the eye region than the mouth, suggesting that some shy children were not avoiding the eyes. Shyness was also correlated with fewer first fixations to the nose, which is thought to reflect the typical global strategy of face processing. Present results replicate and extend recent work on social anxiety and face scanning in adults to shyness in children. These preliminary findings also provide support for the notion that some shy children may be hypersensitive to detecting social cues and intentions in others conveyed by the eyes. Theoretical and practical implications for understanding the social cognitive correlates and treatment of shyness are discussed.  相似文献   
68.
69.
The purpose of this study was to evaluate a single-session peer-led safer sex intervention, based on the Information-Motivation-Behavioral Skills theoretical model, for college students residing in campus residence halls. Participants (N = 108) were assigned to either an hour long control or 5-module intervention session. Compared to the control condition, the intervention increased participants’ information and women’s subjective norms about preventative behavior. Both the control and intervention sessions increased intentions to perform preventative behaviors (e.g., keep condoms available). These preliminary results suggest that this intervention is promising for increasing constructs associated with safer sexual behavior and could easily be implemented by residence hall staff.  相似文献   
70.
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