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   132956篇
  免费   9581篇
  国内免费   302篇
耳鼻咽喉   1197篇
儿科学   3693篇
妇产科学   2818篇
基础医学   20881篇
口腔科学   3410篇
临床医学   11397篇
内科学   26779篇
皮肤病学   2291篇
神经病学   12708篇
特种医学   5655篇
外国民族医学   16篇
外科学   16517篇
综合类   580篇
现状与发展   1篇
一般理论   108篇
预防医学   14970篇
眼科学   2038篇
药学   7966篇
中国医学   240篇
肿瘤学   9574篇
  2023年   564篇
  2022年   941篇
  2021年   2033篇
  2020年   1484篇
  2019年   2159篇
  2018年   2705篇
  2017年   2309篇
  2016年   2476篇
  2015年   2814篇
  2014年   3807篇
  2013年   5027篇
  2012年   7716篇
  2011年   7767篇
  2010年   4045篇
  2009年   4277篇
  2008年   6897篇
  2007年   7153篇
  2006年   6884篇
  2005年   6523篇
  2004年   5524篇
  2003年   5259篇
  2002年   4803篇
  2001年   4649篇
  2000年   4662篇
  1999年   4164篇
  1998年   1778篇
  1997年   1487篇
  1996年   1568篇
  1995年   1286篇
  1994年   1206篇
  1993年   1089篇
  1992年   2823篇
  1991年   2564篇
  1990年   2440篇
  1989年   2275篇
  1988年   2089篇
  1987年   1831篇
  1986年   1752篇
  1985年   1676篇
  1984年   1188篇
  1983年   1034篇
  1982年   564篇
  1981年   502篇
  1980年   429篇
  1979年   899篇
  1978年   558篇
  1977年   460篇
  1974年   449篇
  1973年   435篇
  1972年   391篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
In May 2017, the Health and Environmental Sciences Institute's Genetic Toxicology Technical Committee hosted a workshop to discuss whether mode of action (MOA) investigation is enhanced through the application of the adverse outcome pathway (AOP) framework. As AOPs are a relatively new approach in genetic toxicology, this report describes how AOPs could be harnessed to advance MOA analysis of genotoxicity pathways using five example case studies. Each of these genetic toxicology AOPs proposed for further development includes the relevant molecular initiating events, key events, and adverse outcomes (AOs), identification and/or further development of the appropriate assays to link an agent to these events, and discussion regarding the biological plausibility of the proposed AOP. A key difference between these proposed genetic toxicology AOPs versus traditional AOPs is that the AO is a genetic toxicology endpoint of potential significance in risk characterization, in contrast to an adverse state of an organism or a population. The first two detailed case studies describe provisional AOPs for aurora kinase inhibition and tubulin binding, leading to the common AO of aneuploidy. The remaining three case studies highlight provisional AOPs that lead to chromosome breakage or mutation via indirect DNA interaction (inhibition of topoisomerase II, production of cellular reactive oxygen species, and inhibition of DNA synthesis). These case studies serve as starting points for genotoxicity AOPs that could ultimately be published and utilized by the broader toxicology community and illustrate the practical considerations and evidence required to formalize such AOPs so that they may be applied to genetic toxicity evaluation schemes. Environ. Mol. Mutagen. 61:114–134, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
22.
23.
24.
25.
26.
27.
To improve the diagnostic accuracy of electroencephalography (EEG) criteria for nonconvulsive status epilepticus (NCSE), external validation of the recently proposed Salzburg criteria is paramount. We performed an external, retrospective, diagnostic accuracy study of the Salzburg criteria, using EEG recordings from patients with and without a clinical suspicion of having NCSE. Of the 191 EEG recordings, 12 (12%) was classified as an NCSE according to the reference standard. In the validation cohort, sensitivity was 67% and specificity was 89%. The positive predictive value was 47% and the negative predictive value was 95%. Ten patients in the control group (n = 93) were false positive, resulting in a specificity of 89.2%. The interrater agreement between the reference standards and between the scorers of the Salzburg criteria was moderate; disagreement occurred mainly in patients with an epileptic encephalopathy. The Salzburg criteria showed a lower diagnostic accuracy in our external validation study than in the original design, suggesting that they cannot replace the current practice of careful weighing of both clinical and EEG information on an individual basis.  相似文献   
28.
Objective: A multidisciplinary vocational rehabilitation programme, the Vocational Enablement Protocol (VEP) was developed to address the specific needs of employees with hearing difficulties. In the current study we evaluated the process of implementing the VEP in audiologic care among employees with hearing impairment. Design: In conjunction with a randomized controlled trial, we collected and analysed data on seven process parameters: recruitment, reach, fidelity, dose delivered, dose received and implemented, satisfaction, and perceived benefit. Study sample: Sixty-six employees with hearing impairment participated in the VEP. The multidisciplinary team providing the VEP comprised six professionals. Results: The professionals performed the VEP according to the protocol. Of the recommendations delivered by the professionals, 31% were perceived as implemented by the employees. Compliance rate was highest for hearing-aid uptake (51%). Both employees and professionals were highly satisfied with the VEP. Participants rated good perceived benefit from it. Conclusions: Our results indicate that the VEP could be a useful treatment for employees with hearing difficulties from a process evaluation perspective. Implementation research in the audiological setting should be encouraged in order to further provide insight into parameters facilitating or hindering successful implementation of an intervention and to improve its quality and efficacy.  相似文献   
29.
30.
Since the introduction of cART (combination antiretroviral therapy), HIV has evolved into a chronic disease such that it requires lifelong medical treatment to which patients must adhere. Communication with health care providers is pivotal in supporting patients to adapt to having HIV and adhering to treatment, in order to maintain health and quality of life. Previous research indicates that communication is optimal when it matches patient preferences for information exchange, relationship establishment, and involvement in treatment decisions. The aim of the present study is to explore HIV patient communication preferences as well as patient experiences with their providers (not) matching their preferences. A second aim is to explore provider beliefs about patient preferences and provider views on optimal communication. Data were collected through interviews with 28 patients and 11 providers from two academic hospitals. Results indicate that patient preferences reflect their cognitive, emotional, and practical needs such that patients look to increase their sense of control over their HIV. Patients aim to further increase their sense of control (by proxy) through their relationship with their providers and through their decisional involvement preferences. Providers are well aware of patient communication preferences but do not explicate underlying control needs. Implications for clinical practice are discussed.  相似文献   
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