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   2066篇
  免费   117篇
  国内免费   75篇
耳鼻咽喉   1篇
儿科学   171篇
妇产科学   26篇
基础医学   240篇
口腔科学   58篇
临床医学   251篇
内科学   488篇
皮肤病学   73篇
神经病学   58篇
特种医学   391篇
外科学   92篇
综合类   46篇
预防医学   101篇
眼科学   19篇
药学   130篇
  2篇
肿瘤学   111篇
  2023年   4篇
  2022年   5篇
  2021年   11篇
  2020年   14篇
  2019年   17篇
  2018年   33篇
  2017年   22篇
  2016年   22篇
  2015年   39篇
  2014年   48篇
  2013年   59篇
  2012年   39篇
  2011年   38篇
  2010年   89篇
  2009年   84篇
  2008年   51篇
  2007年   88篇
  2006年   52篇
  2005年   57篇
  2004年   25篇
  2003年   18篇
  2002年   30篇
  2001年   38篇
  2000年   30篇
  1999年   31篇
  1998年   131篇
  1997年   156篇
  1996年   134篇
  1995年   110篇
  1994年   116篇
  1993年   102篇
  1992年   35篇
  1991年   37篇
  1990年   40篇
  1989年   60篇
  1988年   51篇
  1987年   44篇
  1986年   51篇
  1985年   48篇
  1984年   27篇
  1983年   16篇
  1982年   25篇
  1981年   29篇
  1980年   26篇
  1979年   5篇
  1978年   8篇
  1977年   20篇
  1976年   26篇
  1975年   14篇
  1966年   1篇
排序方式: 共有2258条查询结果,搜索用时 390 毫秒
991.
992.
993.
Background:This article presents the design of PROFILe, a study investigating which (bio)medical and non-(bio)medical patient characteristics should guide more tailored chronic care. Based on this insight, the project aims to develop and validate ‘patient profiles’ that can be used in practice to determine optimal treatment strategies for subgroups of chronically ill with similar healthcare needs and preferences.Methods/Design:PROFILe is a practice-based research comprising four phases. The project focuses on patients with type 2 diabetes. During the first study phase, patient profiles are drafted based on a systematic literature research, latent class growth modeling, and expert collaboration. In phase 2, the profiles are validated from a clinical, patient-related and statistical perspective. Phase 3 involves a discrete choice experiment to gain insight into the patient preferences that exist per profile. In phase 4, the results from all analyses are integrated and recommendations formulated on which patient characteristics should guide tailored chronic care.Discussion:PROFILe is an innovative study which uses a uniquely holistic approach to assess the healthcare needs and preferences of chronically ill. The patient profiles resulting from this project must be tested in practice to investigate the effects of tailored management on patient experience, population health and costs.  相似文献   
994.
995.
996.
One of the challenges of tailored antiangiogenic therapy is the ability to adequately monitor the angiogenic activity of a malignancy in response to treatment. The αvβ3 integrin, highly overexpressed on newly formed tumor vessels, has been successfully used as a target for Arg-Gly-Asp (RGD)-functionalized nanoparticle contrast agents. In the present study, an RGD-functionalized nanocarrier was used to image ongoing angiogenesis in two different xenograft tumor models with varying intensities of angiogenesis (LS174T > EW7). To that end, iron oxide nanocrystals were included in the core of the nanoparticles to provide contrast for T2*-weighted magnetic resonance imaging (MRI), whereas the fluorophore Cy7 was attached to the surface to enable near-infrared fluorescence (NIRF) imaging. The mouse tumor models were used to test the potential of the nanoparticle probe in combination with dual modality imaging for in vivo detection of tumor angiogenesis. Pre-contrast and post-contrast images (4 hours) were acquired at a 9.4-T MRI system and revealed significant differences in the nanoparticle accumulation patterns between the two tumor models. In the case of the highly vascularized LS174T tumors, the accumulation was more confined to the periphery of the tumors, where angiogenesis is predominantly occurring. NIRF imaging revealed significant differences in accumulation kinetics between the models. In conclusion, this technology can serve as an in vivo biomarker for antiangiogenesis treatment and angiogenesis phenotyping.  相似文献   
997.

Background  

Women with Down syndrome very rarely develop breast cancer even though they now live to an age when it normally occurs. This may be related to the fact that Down syndrome persons have an additional copy of chromosome 21 where the gene that codes for the antiangiogenic protein Endostatin is located. Can this information lead to a primary antiangiogenic therapy for early stage breast cancer that indefinitely prolongs remission? A key question that arises is when is the initial angiogenic switch thrown in micrometastases? We have conjectured that avascular micrometastases are dormant and relatively stable if undisturbed but that for some patients angiogenesis is precipitated by surgery. We also proposed that angiogenesis of micrometastases very rarely occurs before surgical removal of the primary tumor. If that is so, it seems possible that we could suggest a primary antiangiogenic therapy but the problem then arises that starting a therapy before surgery would interfere with wound healing.  相似文献   
998.
In order to clarify which teaching form encourages student' s self-motivation learning ability better, we did a comparison experiment between problem-based learning (PBL)and lecture-based learning (LBL) in a 3rd year course in basic pharmacology. Of 224 students who participated (124 PBL, 100 LBL) in pharmacology course, the experimental group was divided into 6 teams(20 - 21 students for each team with one tutor)using PBL method with 7 clinical cases discussion while o.ther 100 students held in the same lecture-based format as the traditional LBL course as a control group. In 224 students, 50.4% using PBL method self-directed learning ability had increased compared with 35.3% in LBL teaching mode. The test score indicated that students using LBL teaching method scored overall higher than those using PBL mode, especially at objective items, this result was significant.. iy different(P =0.009). However, as far as subjective items are concerned, students accepted PBL mode showed their superior advantages over the LBL ones. Similarly, the result was significantly different( P =0.001 ). On the whole, PBL method supported by appropriate technology and teachers, has allowed our students to analyze authentic situations as a doctor status and the active learning ability by self-motivation study will be undoubtedly beneficial for their becoming life-long learners and excellent doctors in the future.  相似文献   
999.
1000.
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