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   16601篇
  免费   1214篇
  国内免费   32篇
耳鼻咽喉   118篇
儿科学   649篇
妇产科学   486篇
基础医学   2084篇
口腔科学   247篇
临床医学   2682篇
内科学   2855篇
皮肤病学   164篇
神经病学   1402篇
特种医学   272篇
外国民族医学   1篇
外科学   1276篇
综合类   575篇
一般理论   37篇
预防医学   2528篇
眼科学   308篇
药学   906篇
中国医学   8篇
肿瘤学   1249篇
  2023年   78篇
  2022年   44篇
  2021年   314篇
  2020年   208篇
  2019年   308篇
  2018年   325篇
  2017年   244篇
  2016年   315篇
  2015年   386篇
  2014年   486篇
  2013年   810篇
  2012年   1179篇
  2011年   1242篇
  2010年   581篇
  2009年   555篇
  2008年   1062篇
  2007年   1201篇
  2006年   1153篇
  2005年   1144篇
  2004年   1153篇
  2003年   1081篇
  2002年   1030篇
  2001年   144篇
  2000年   113篇
  1999年   156篇
  1998年   210篇
  1997年   196篇
  1996年   186篇
  1995年   180篇
  1994年   144篇
  1993年   118篇
  1992年   87篇
  1991年   76篇
  1990年   96篇
  1989年   91篇
  1988年   90篇
  1987年   59篇
  1986年   67篇
  1985年   61篇
  1984年   74篇
  1983年   73篇
  1982年   72篇
  1981年   87篇
  1980年   75篇
  1979年   63篇
  1978年   52篇
  1977年   51篇
  1976年   47篇
  1975年   28篇
  1974年   41篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
92.
Summary A total of 16 patients with recurrent epithelial ovarian cancer were treated with sulofenur (LY 186641), a novel oral sulfonylurea. All subjects had received previous chemotherapy. Anaemia occurred in all 16 patients, 14 of whom required a blood transfusion, and 2/16 patients received methylene blue for breathlessness due to methaemaglobinaemia. Treatment was discontinued in 2/16 cases due to rising liver enzyme values, which reverted to normal on cessation of the drug. There was no nausea or alopecia. Only two minor responses were seen. Plasma drug levels were insufficient to result in antitumour activity as extrapolated from animal data. Further studies that attempt to increase the bioavailability and improve the therapeutic index are warranted.  相似文献   
93.
94.
GABAA receptor (GABAR) isoforms in the central nervous system are composed of combinations of α(1–6), β(1–4), γ(1–4), δ(1) and (1) subunit subtypes arranged in a pentamer. Many regions of the brain express high levels of mRNA encoding several different subunits and even multiple subunit subtypes. The stoichiometry of GABAR isoforms is unclear, and the number and identity of individual subunit subtypes that are coassembled remain uncertain. To examine the role of β subunit subtypes in the functional properties of GABARS and to determine whether multiple β subtypes can be coassembled in functional GABARs, plasmids containing cDNAs encoding rat β1 and/or β3, α5 and γ2L subtypes were cotransfected into L929 fibroblasts. The properties of the expressed receptor populations were determined using whole-cell and single-channel recording techniques. The α5β1γ2L isoform was less sensitive to GABA than the α5β3γ2L isoform. α5β1γ2L isoform currents were also insensitive to the allosteric modulator loreclezole, while α5β3γ2L isoform currents were strongly potentiated by loreclezole. Fibroblasts transfected with plasmids containing cDNAs for both β1 and β3 subtypes along with α5 and γ2L subtypes produced a receptor population with an intermediate sensitivity to GABA which was insensitive to loreclezole. These results suggest that functional GABARs can be formed that contain two different β subunit subtypes with properties different from receptors that contain only a single β subtype and that the β subunit subtypes influence the response of GABARs to GABA and to the allosteric modulator loreclezole.  相似文献   
95.
96.
Background: Exercise is an important strategy with potential to improve recovery in older adults following a hip fracture.Purpose: The purpose of this study was to test the impact of a self-efficacy based intervention, the Exercise Plus Program, and the different components of the intervention, on self-efficacy, outcome expectations, and exercise behavior among older women post-hip fracture.Methods: Participants were randomized to one of four groups: exercise plus, exercise only, plus only (i.e., motivation), or routine care. Data collection was done at baseline (within 22 days of fracture), 2, 6, and 12 months post-hip fracture.Results: A total of 209 women were recruited with an average age of 81.0 years (SD=6.9). The majority was White (97.1%), was widowed (57.2%), and had a high school education (66.7%). Generalized Estimating Equations were used to perform repeated measures analyses. No differences in trajectories of recovery were observed for self-efficacy or outcome expectations. A statistically significant difference in the overall trajectory of time in exercise was seen (p<.001), with more time spent exercising in all three treatment groups.Conclusions: The study demonstrated that it was possible to engage these women in a home-based exercise program and that the plus only, exercise only, and the exercise plus groups all increased exercise. Support for this project was provided by National Institute on Aging grants R37 AG09901, R01-AG18668, R01 AG17082, and the Claude D. Pepper Older Americans Independence Center P60-AG12583.  相似文献   
97.
PURPOSE: To explore maternal responsiveness in the first 2 to 4 months after delivery and to evaluate potential predictors of maternal responsiveness, including infant feeding, maternal characteristics, and demographic factors such as age, socioeconomic status, and educational level. DESIGN AND METHODS: A cross-sectional survey design was used to assess the variables of maternal responsiveness, feeding patterns, and maternal characteristics in a convenience sample of 177 mothers in the first 2 to 4 months after delivery. The 60-item self-report instrument included scales to measure maternal responsiveness, self-esteem, and satisfaction with life as well as infant feeding questions and sociodemographic items. An online data-collection strategy was used, resulting in participants from 41 U.S. states. FINDINGS: Multiple regression analysis showed that satisfaction with life, self-esteem, and number of children, but not breastfeeding, explained a significant portion of the variance in self-reported maternal responsiveness scores. In this analysis, sociodemographic variables such as age, education, income, and work status showed little or no relationship to maternal responsiveness scores. CONCLUSIONS: This study provides additional information about patterns of maternal behavior in the transition to motherhood and some of the variables that influence that transition. Satisfaction with life was a new predictor of maternal responsiveness. However, with only 15% of the variance explained by the predictors in this study, a large portion of the variance in maternal responsiveness remains unexplained. Further research in this area is needed.  相似文献   
98.
99.
Reflective inquiry in nursing practice or 'revealing images'   总被引:1,自引:0,他引:1  
Reflective inquiry in nursing practice or 'revealing images' Nurses live and work in complex practice worlds; worlds of shrinking resources and expanding needs. Reflection through journaling offers unique opportunities to gain insight into practice. What might we learn from one's journal? A reflective journal can be a source of interplay between the self as written and the self as other. Likewise, the journal may act to situate ourselves in practice, while at the same time enabling us to illuminate how and in what ways our understandings have become distorted. The extent to which one's journal is educative depends upon the manner in which one chooses to use it as a transformative tool, a tool that might well be described as a process of healing and enlightenment. In order to illustrate the reflexive nature of journaling, this paper is presented as a play reading, where a conversation about practice stories between the different aspects of the nurse's self is depicted. In adopting a play reading, an alternative pedagogical tool is used to illustrate different methodologies exemplifying the emergence of how and in what ways we develop and reconstruct our understanding in nursing.  相似文献   
100.
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