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   1841篇
  免费   106篇
  国内免费   41篇
耳鼻咽喉   14篇
儿科学   74篇
妇产科学   27篇
基础医学   213篇
口腔科学   46篇
临床医学   182篇
内科学   452篇
皮肤病学   36篇
神经病学   139篇
特种医学   201篇
外科学   209篇
综合类   21篇
预防医学   106篇
眼科学   28篇
药学   115篇
中国医学   4篇
肿瘤学   121篇
  2023年   13篇
  2022年   11篇
  2021年   31篇
  2020年   31篇
  2019年   47篇
  2018年   58篇
  2017年   40篇
  2016年   28篇
  2015年   44篇
  2014年   71篇
  2013年   75篇
  2012年   100篇
  2011年   105篇
  2010年   100篇
  2009年   71篇
  2008年   73篇
  2007年   110篇
  2006年   77篇
  2005年   75篇
  2004年   67篇
  2003年   42篇
  2002年   53篇
  2001年   41篇
  2000年   40篇
  1999年   34篇
  1998年   58篇
  1997年   52篇
  1996年   48篇
  1995年   47篇
  1994年   42篇
  1993年   28篇
  1992年   14篇
  1991年   27篇
  1990年   15篇
  1989年   37篇
  1988年   30篇
  1987年   17篇
  1986年   20篇
  1985年   11篇
  1984年   11篇
  1983年   10篇
  1982年   11篇
  1981年   11篇
  1980年   12篇
  1979年   6篇
  1978年   8篇
  1977年   12篇
  1976年   7篇
  1970年   3篇
  1968年   3篇
排序方式: 共有1988条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.

Objective  

The aim of the project was to assess the effectiveness and safety of weekly epoetin-beta (EB) in patients with gastrointestinal cancer (GIC) subjected to concomitant chemoradiotherapy (CCTRT).  相似文献   
5.
INTRODUCTION: Traditional advanced imaging modalities such as CT and MRI are limited in their ability to perform accurate linear distance and angular measurements regardless of anatomical orientation. The construction of 3D models has been used to perform anthropometric analyses as well as in the reconstruction of rapid prototypes. We hypothesized that such measurements would be precise to within 2 mm or 2 degrees of measurements performed with a coordinate measurement machine (CMM). We also hypothesized that there would be a high degree of interobserver reliability with these measurements. MATERIALS AND METHODS: Multiple aluminum screws were implanted in various positions in three foam pelvises which were subsequently scanned by CT and rendered as 3D models using a commercially available software package (Mimics). Linear and angular measurements were performed using a CMM machine, the software package, and a dial caliper or goniometer. The deviation of the measurements from the CMM data was compared using ANOVA. The interobserver reliability of both the manual and computer-generated measurements was calculated. RESULTS: The mean difference between the CMM distances and those measured manually and with the software was 2.12 +/- 1.20 mm and 1.57 +/- 1.05 mm, respectively. The mean difference between the CMM angular measurements and the angular measurements performed manually and with the software was 4.07 +/- 4.70 degrees and 1.62 +/- 1.32 degrees, respectively. In all cases, the manual measurements were significantly less accurate (p < 0.0001) and there was a high degree of interobserver reliability. CONCLUSIONS: Computer-generated measurements taken from three-dimensionally reconstructed models are more accurate than manual measurements and are within 2 mm and 2 degrees of measurements performed with a CMM. These measurements have high interobserver reliability.  相似文献   
6.
7.
8.
The Monte Carlo method was used to calculate the efficiency, escape and Compton curves of a planar high-purity germanium detector (HPGe) in the 20-150 keV energy. These curves were used for the determination of photons spectra produced by an X-ray machine in order to allow a precise characterization of photon beams applied to medical diagnosis. The detector was modeled with the MCNP5 computer code and validated by comparison with experimental data. The air kerma calculated after the spectra stripping was compared with ionization chamber measurements.  相似文献   
9.
Venous leg ulcers derived from tissue destruction is the consequence of a chronic inflammatory process that produces pain and physical disability, diminishing quality of life in patients. In this work, Lassar ointment and lyophilized collagen‐polyvinylpyrrolidone were administered separated each on one half in the same ulcer to 9 patients at the beginning and every 4 days. On day 16, all patients were auto‐grafted with partial thickness skin. Granulation tissue and graft integration were assessed clinically during 3 months. Inflammatory infiltrate, type I and III collagens, elastic fibers, alkaline phosphatase as well as blood vessels were evaluated histologically or histochemically in biopsies taken at the beginning and 16 days after the local treatment. Clinically and morphologically, both treatments demonstrated appropriate granulation tissue promotion and optimal graft integration since the beginning. Nevertheless, in Lassar ointment treated group regionalization of alkaline phosphatase activity was observed, as well as the presence of granuloma in 2 of the 9 patients. In conclusion, Lassar ointment or lyophilized collagen‐polyvinylpyrrolidone are two different promoters of granulation tissue in venous leg ulcers, however Lassar ointment has the capability to produce granuloma and an exacerbated immune response; in consequence, ulcer recidivism could be present, may be due to mineral deposits in the wound.  相似文献   
10.
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