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   14314篇
  免费   981篇
  国内免费   61篇
耳鼻咽喉   118篇
儿科学   420篇
妇产科学   396篇
基础医学   1853篇
口腔科学   270篇
临床医学   2448篇
内科学   2475篇
皮肤病学   197篇
神经病学   1360篇
特种医学   364篇
外国民族医学   1篇
外科学   1271篇
综合类   102篇
一般理论   16篇
预防医学   1924篇
眼科学   220篇
药学   769篇
  1篇
中国医学   14篇
肿瘤学   1137篇
  2023年   59篇
  2022年   114篇
  2021年   316篇
  2020年   182篇
  2019年   348篇
  2018年   300篇
  2017年   252篇
  2016年   304篇
  2015年   361篇
  2014年   530篇
  2013年   707篇
  2012年   1146篇
  2011年   1114篇
  2010年   593篇
  2009年   518篇
  2008年   1003篇
  2007年   1058篇
  2006年   992篇
  2005年   935篇
  2004年   912篇
  2003年   798篇
  2002年   855篇
  2001年   109篇
  2000年   73篇
  1999年   120篇
  1998年   186篇
  1997年   163篇
  1996年   134篇
  1995年   114篇
  1994年   83篇
  1993年   103篇
  1992年   54篇
  1991年   57篇
  1990年   43篇
  1989年   57篇
  1988年   27篇
  1987年   27篇
  1986年   46篇
  1985年   35篇
  1984年   59篇
  1983年   45篇
  1982年   56篇
  1981年   45篇
  1980年   39篇
  1979年   28篇
  1978年   39篇
  1977年   29篇
  1976年   19篇
  1975年   19篇
  1974年   24篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
The purpose of this literature review is to evaluate the scientific evidence regarding the relationship between obesity and outcome of renal transplant recipients. The impact of obesity on kidney transplant outcomes continues to be controversial. Obesity seems to influence delayed graft failure, graft survival, and patient survival. A body mass index of 35 kg/m(2) or more is significant for greater posttransplant complications, especially new-onset transplant diabetes mellitus, wound complications, and posttransplant weight gain. Several important advances in the general medical management of the patient, both before and after transplantation, have occurred over the last decade. The decrease in mortality may be related to better patient management, whereas the improvement in graft survival is most likely the result of more effective immunotherapy and better management of hypertension and hyperlipidemia, which overall lessens the risk of obesity among kidney transplant recipients.  相似文献   
42.
43.
44.
Ethanol is a recognized immunosuppressive agent in the chronic alcoholic. However, the effects of ethanol exposure on the developing immune system have not been extensively investigated. This study evaluated the effects of early postnatal ethanol exposure, via breast milk, on splenic lymphocyte differentiation antigen expression in offspring reared by ethanol-fed mice. Maternal mice were fed a liquid diet containing 20% ethanol-derived calories during pregnancy (E-P), pregnancy and lactation (E-PL), or lactation (E-L). Ad libitumfed (C) and pair-fed (PF) control groups, fed a control liquid diet, were included. Expression of differentiation antigens on splenic lymphocytes from 21-day-old offspring reared by females in 1 of the 3 ethanol exposure conditions was evaluated by flow cytometry. Offspring reared by E-P females had similar numbers of splenic lymphocytes as offspring reared by C and pair-fed during pregnancy (PF-P) females. In contrast, offspring reared by E-PL and E-L females had fewer splenic lymphocytes than both PF-PL and PF-L (respectively), and C offspring. The number of Thy 1.2+, CD4+, CD8+, and IgG+ (B-cell) splenic lymphocytes was reduced in E-PL and E-L offspring compared with PF and C offspring. E-P offspring had fewer CD4+ and IgG+ splenic lymphocytes than C, but not PF-P, offspring. The percentage of Thy 1.2+ splenic lymphocytes was significantly reduced among E-PL and E-L offspring compared with PF-PL and PF-L (respectively), and C offspring. These results suggest that ethanol exposure of female mice during pregnancy, pregnancy and lactation, or lactation alone, alters the phenotypic development of splenic lymphocytes of offspring reared by these females. The greatest effect on differentiation antigen expression occurred when females consumed ethanol during the period of lactation. We speculate that direct exposure of the nursing offspring to ethanol via the breast milk was responsible for the reductions in specific splenic lymphocyte populations. These data demonstrate that mice reared by females fed ethanol during the early postnatal period have a marked depletion of each of the major subpopulations of splenic lymphocytes, and that Thy 1.2+ lymphocytes are differentially sensitive to ethanol.  相似文献   
45.
The current study presents both longitudinal behavioral data and functional activation data documenting the effects of early focal brain injury on the development of spatial analytic processing in two children, one with prenatal left hemisphere (LH) injury and one with right hemisphere (RH) injury. A substantial body of evidence has shown that adults and children with early, lateralized brain injury show evidence of spatial analytic deficits. LH injury compromises the ability to encode the parts of a spatial pattern, while RH injury impairs pattern integration. The two children described in this report show patterns of deficit consistent with the site of their injury. In the current study, their longitudinal behavioral data spanning the age range from preschool to adolescence are presented in conjunction with data from a functional magnetic resonance imaging (fMRI) study of spatial processing. The activation results provide evidence that alternative profiles of neural organization can arise following early focal brain injury, and document where in the brain spatial functions are carried out when regions that normally mediate them are damaged. In addition, the coupling of the activation with the behavioral data allows us to go beyond the simple mapping of functional sites, to ask questions about how those sites may have come to mediate the spatial functions.  相似文献   
46.
47.
PURPOSE: The purpose of this study was to develop and evaluate measures reflecting the onset of tense marking for children between the ages of 2;0 (years;months) and 3;0. METHOD: The validity of 4 cumulative measures of tense marker emergence and productivity was evaluated relative to existing measures of early grammatical development in a sample of 20 children followed longitudinally. Fourteen children were at risk for specific language impairment (AR-SLI group), and 6 children had low average language abilities (LA group). RESULTS: All measures of onset were highly correlated with the traditional measures; however, children's progress toward mastery of grammatical tense marking was best explained by the productivity of their tense marking systems. Finally, the onset measures imposing productivity requirements best differentiated children in the LA group from those in the AR-SLI group. CONCLUSIONS: The clinical implications for using the late onset of tense marking to improve the early identification of SLI are discussed.  相似文献   
48.
Complementary modalities, used alone or in combination with pharmacologic therapies, play an important role in the prevention and management of postoperative nausea and vomiting (PONV) and post discharge nausea and vomiting (PDNV). This article will review the evidence for the effective use of complementary modalities: acupuncture and related techniques, aromatherapy, and music therapy that may be integrated in the perianesthesia nurse's plan of care to prevent or manage PONV.  相似文献   
49.
50.
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