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   2115篇
  免费   146篇
  国内免费   10篇
耳鼻咽喉   37篇
儿科学   95篇
妇产科学   39篇
基础医学   229篇
口腔科学   58篇
临床医学   188篇
内科学   468篇
皮肤病学   127篇
神经病学   188篇
特种医学   148篇
外国民族医学   3篇
外科学   172篇
综合类   53篇
一般理论   10篇
预防医学   181篇
眼科学   120篇
药学   87篇
肿瘤学   68篇
  2021年   24篇
  2019年   25篇
  2018年   28篇
  2017年   22篇
  2016年   30篇
  2015年   33篇
  2014年   46篇
  2013年   54篇
  2012年   93篇
  2011年   98篇
  2010年   41篇
  2009年   53篇
  2008年   76篇
  2007年   94篇
  2006年   88篇
  2005年   76篇
  2004年   85篇
  2003年   75篇
  2002年   58篇
  2001年   65篇
  2000年   69篇
  1999年   51篇
  1998年   33篇
  1997年   17篇
  1996年   37篇
  1995年   23篇
  1994年   21篇
  1992年   47篇
  1991年   41篇
  1990年   53篇
  1989年   47篇
  1988年   41篇
  1987年   37篇
  1986年   54篇
  1985年   43篇
  1984年   29篇
  1983年   29篇
  1981年   22篇
  1980年   22篇
  1979年   28篇
  1978年   23篇
  1977年   31篇
  1976年   28篇
  1975年   23篇
  1974年   24篇
  1973年   30篇
  1972年   28篇
  1971年   27篇
  1970年   26篇
  1969年   22篇
排序方式: 共有2271条查询结果,搜索用时 0 毫秒
71.
72.
Factors that contribute to bone fragility in type 2 diabetes are not well understood. We assessed the effects of intensive glycemic control, thiazolidinediones (TZDs), and A1C levels on bone geometry and strength at the radius and tibia. In a substudy of the Action to Control Cardiovascular Risk in Diabetes trial, peripheral quantitative computed tomographic (pQCT) scans of the radius and tibia were obtained 2 years after randomization on 73 participants (intensive n = 35, standard n = 38). TZD use and A1C levels were measured every 4 months during the trial. Effects of intervention assignment, TZD use, and A1C on pQCT parameters were assessed in linear regression models. Intensive, compared with standard, glycemic control was associated with 1.3 % lower cortical volumetric BMD at the tibia in men (p = 0.02) but not with other pQCT parameters. In women, but not men, each additional year of TZD use was associated with an 11 % lower polar strength strain index (SSIp) at the radius (p = 0.04) and tibia (p = 0.002) in models adjusted for A1C levels. In women, each additional 1 % increase in A1C was associated with an 18 % lower SSIp at the ultradistal radius (p = 0.04) in models adjusted for TZD use. There was no consistent evidence of an effect of intensive, compared with standard, glycemic control on bone strength at the radius or tibia. In women, TZD use may reduce bone strength at these sites. Higher A1C may also be associated with lower bone strength at the radius, but not tibia, in women.  相似文献   
73.
Our research aims were to: (1) assess the prevalence of two condom use problems: breakage or slippage and partial use (delayed application or early removal) among men who have sex with men (MSM) seeking services in urban US STD clinics; and (2) examine the association between these condom use problems and participant, partner and partnership characteristics. Analysis was restricted to HIV-negative MSM who reported having anal sex at least once in the preceding 3 months and who completed both the baseline and 3 month follow-up assessments. Two models were fitted using the generalized estimating equations (GEE) approach. A total of 263 MSM (median age=32 years) reported 990 partnerships. Partnerships with no condom use 422 (42.6%) were excluded. Thus, 207 MSM and 568 partnerships were included. Among condom users, 100% use was reported within 454 partnerships (79.9%) and <100% within 114 (20.1%), and 21(3.7%) reported both condom use problems, 25 (4.4%) reported only breakage, 67 (11.8%) reported only partial use, and 455 (80.1%) reported no errors. The breakage or slippage and partial use rates per condom used were 3.4% and 11.2%, respectively. A significantly higher rate of breakage or slippage occurred among non-main partnerships. Characteristics associated with increased odds for condom breakage or slippage were: lower education level (OR=2.78; CI: 1.1-7.5), non-main partner status (OR=4.1; CI: 1.5-11.7), and drunk or high during sex (OR=2.0; CI: 1.1-3.8), and for partial use: lower education level (OR=2.6; CI: 1.0-6.6), perceived partner sexually transmitted infections (STI) risk (OR=2.4; CI: 1.3-4.2), and inconsistent condom use (OR=3.7; CI: 2.0-6.6). A high percentage of MSM partnerships reported no condom use and among condom users, a sizable proportion did not use them consistently or correctly. MSM may benefit from interventions designed to increase proficiency for condom use with a particular focus on the behaviors of inconsistent and partial condom use.  相似文献   
74.
75.
76.
77.

Background

To advance equity and to enhance leadership skills, self-advocates with intellectual/developmental disabilities are now part of the cohort of trainees in the University of North Carolina LEND, which means that they fully participate in the Interdisciplinary Leadership Development Program, a collaboration among programs in public health, social work, and LEND, which meets monthly.

Objective

Given this important new participation by self-advocates, this study analyzes the reflections of graduate students on the contributions of self-advocates to their leadership training.

Methods

At the conclusion of the program each year, graduate students respond to a questionnaire about how self-advocates influenced the content and interactions/discussions of the monthly workshops and are asked to provide specific examples to explain their perceptions. The 12 MCH leadership competencies were used to guide the coding of the comments for this qualitative, directed content analysis.

Results

Forty-six of 58 students (79.3%) from two consecutive cohorts responded for this cross-sectional study. Interactions with self-advocates prompted comments on 8 of the 12 leadership competencies, including interdisciplinary team building (29% of the comments); developing others through teaching and mentoring (22%); and self-reflection (18%).

Conclusions

The inclusion of self-advocates throughout an interdisciplinary leadership development program for graduate students in health affairs can strengthen MCH leadership competencies for all participants as they enter an increasingly interdisciplinary workforce.  相似文献   
78.
79.
Recent advances in multiparametric magnetic resonance imaging (MRI) have enabled image-guided detection of prostate cancer. Fusion of MRI with real-time ultrasound (US) allows the information from MRI to be used to direct biopsy needles under US guidance in an office-based procedure. Fusion can be performed either cognitively or electronically, using a fusion device. Fusion devices allow superimposition (coregistration) of stored MRI images on real-time US images; areas of suspicion found on MRI can then serve as targets during US-guided biopsy. Currently available fusion devices use a variety of technologies to perform coregistration: robotic tracking via a mechanical arm with built-in encoders (Artemis/Eigen, BioJet/Geoscan); electromagnetic tracking (UroNav/Philips-Invivo, Hi-RVS/Hitachi); or tracking with a 3D US probe (Urostation/Koelis). Targeted fusion biopsy has been shown to identify more clinically significant cancers and fewer insignificant cancers than conventional biopsy. Fusion biopsy appears to be a major advancement over conventional biopsy because it allows (1) direct targeting of suspicious areas not seen on US and (2) follow-up biopsy of specific cancerous sites in men undergoing active surveillance.  相似文献   
80.
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