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   12377篇
  免费   981篇
  国内免费   35篇
耳鼻咽喉   124篇
儿科学   320篇
妇产科学   207篇
基础医学   1484篇
口腔科学   297篇
临床医学   1489篇
内科学   2123篇
皮肤病学   116篇
神经病学   1053篇
特种医学   427篇
外科学   2155篇
综合类   152篇
一般理论   5篇
预防医学   1308篇
眼科学   188篇
药学   1105篇
中国医学   9篇
肿瘤学   831篇
  2023年   62篇
  2022年   147篇
  2021年   305篇
  2020年   190篇
  2019年   283篇
  2018年   337篇
  2017年   275篇
  2016年   277篇
  2015年   326篇
  2014年   457篇
  2013年   593篇
  2012年   935篇
  2011年   868篇
  2010年   467篇
  2009年   413篇
  2008年   696篇
  2007年   739篇
  2006年   675篇
  2005年   712篇
  2004年   630篇
  2003年   609篇
  2002年   518篇
  2001年   167篇
  2000年   148篇
  1999年   185篇
  1998年   103篇
  1997年   95篇
  1996年   84篇
  1995年   75篇
  1994年   70篇
  1993年   66篇
  1992年   111篇
  1991年   107篇
  1990年   101篇
  1989年   97篇
  1988年   92篇
  1987年   82篇
  1986年   85篇
  1985年   84篇
  1984年   99篇
  1983年   73篇
  1982年   55篇
  1981年   64篇
  1980年   50篇
  1979年   72篇
  1978年   69篇
  1977年   54篇
  1976年   66篇
  1974年   63篇
  1973年   68篇
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
11.
Quality of Life Research - Health-related quality of life (HRQoL) is an important indicator of population health, yet no age-specific trend analyses in HRQoL have been conducted with a nationally...  相似文献   
12.
13.
Is it possible to modify intake behaviors for body weight control purposes? Over the last 40 years, dozens of international, peer-reviewed articles have described behavior modification approaches aiming at body weight reduction. The present article first presents a historical account of behavioral methods and their results. From the early therapies exclusively addressing behaviors (excluding restrictive diets) until the recent cognitive-behavioral treatments, published studies have reported modest weight losses associated with numerous metabolic, nutritional and psychological benefits whose maintenance, beyond the treatment duration, appear reasonably good. Recent studies specifically address the conditions of long-term maintenance. The main elements of behavioral-cognitive treatments are described briefly. Finally, the particular problems associated with these approaches in the French context are underlined.  相似文献   
14.
Campath-1H (alemtuzumab) induction was used for renal transplantation in combination with sirolimus as immunosuppression. We previously reported a high (28%) rate of early rejection with this regimen, and now report 3-year outcomes. Twenty-nine patients were recipients of either deceased donor or non-HLA (Human Leukocyte Antigen) identical living donor primary renal allografts. Clinical parameters including infection, malignancy, kidney function, and kidney histology were followed prospectively for 3 years. Three-year cumulative graft and patient survival were 96% and 100%, respectively. Twenty patients were maintained on steroid-free immunosuppressive regimens, and 15 patients were maintained on monotherapy for immunosuppression (12 on sirolimus). No serious infectious complications were observed and two patients developed basal cell skin cancer. The 3-year results of our initial pilot study demonstrate good graft (96%) and patient (100%) outcomes. Campath-1H induction has yielded a high proportion of patients maintained on immunosuppressive monotherapy (57%) without serious infectious- and no malignancy-related complications. The reported regimen yielded novel insights into both Campath-1H and sirolimus therapy in renal transplantation. Because of the higher incidence of early rejection, we recommend a modified strategy of immunosuppression including a brief course of a calcineurin inhibitor.  相似文献   
15.
16.
Diarrhetic shellfish poisoning (DSP) is a serious and globally widespread phytoplankton-related seafood illness. Although DSP is rarely life-threatening, it causes incapacitating diarrhea and vomiting with no known medical treatments. In addition, phytoplankton producing DSP toxins have been identified in temperate coastal waters worldwide, and their numbers may be increasing as a result of coastal eutrophication. The toxic effects of the major DSP toxins, okadaic acid and dinophysistoxin-1 (35-methylokadaic acid), appear to originate from their inhibitory activity against a family of structurally related serine/threonine protein phosphatases (PSPases). In particular, the inhibition of essential PSPases (e.g. PP1 and PP2A) has catastrophic consequences in most eukaryotic cells. Exploiting the potent inhibitory property of the DSP toxins, we have developed an enzyme-based assay (PP2A assay) capable of detecting both okadaic acid and dinophysis- toxin-1 in nanogram amounts. The assay employs purified PP2A, which has an extremely high affinity for both DSP toxins. This provides the PP2A assay with a level of sensitivity comparable to, or surpassing, that of most monoclonal antibody probes. To evaluate the PP2A assay as a means of detecting contaminated shellfish, a series of spike recovery experiments was conducted. The findings from these studies suggest that the PP2A assay has the potential for development into a rapid and relatively simple method for detecting PSPase inhibitors in crude extracts produced from shellfish.  相似文献   
17.
18.
Contemporary discourse contains numerous examples of use of the concept of culture by social and behavioral scientists. Simple reification, where the speaker makes culture into a thing capable of action exemplifies one usage in public discourse. Some quantitative social scientists attempt to characterize people’s cultural identities by means of a single categorical variable, which often “lumps” people into categories such as “Hispanic” or “Black” that in fact have numerous culturally bounded subcategories. Approaches that emphasize cultural process are preferable to those who attempt to categorize; more complex measures of acculturation help investigators to make convincing analyses of circumstances in which health disparities occur. Examples in which investigators make appropriate use of cultural characterizations demonstrate their utility in investigating health disparities in Haitian American women, injecting and noninjecting drug users, Hispanic youth, and adult Hispanics at risk of HIV infection. Focus on culture in the study of health disparities can identify entanglements between structural factors such as poverty and lack of education and cultural factors such as beliefs about health. Qualitative methods coupled with quantitative methods have great potential to improve investigators’ grasp of cultural nuance while capturing the distribution of qualitatively derived behaviors.  相似文献   
19.
20.
Prisons and prison inmates present important targets for HIV/AIDS prevention interventions. Inmates often have histories of high-risk behavior that place them in danger of contracting HIV/AIDS, and rates of HIV/AIDS tend to be much higher in this population. The goal of this study was to assess the effectiveness of a prison-based HIV/AIDS intervention to change attitudes toward HIV prevention, norms supporting HIV prevention, perceived behavioral control (i.e., self-efficacy) for HIV prevention behaviors, and intentions to engage in HIV prevention behaviors postrelease. The intervention also had the goal of encouraging inmates to become HIV/AIDS peer educators. The intervention appeared most successful at influencing beliefs and behaviors related to peer education and somewhat successful at influencing beliefs and intentions related to condom use. Analyses also showed some significant differences in effectiveness by race/ethnicity. Results are discussed from the perspectives of both research and practice with regard to prison-based HIV prevention efforts.  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