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   7856篇
  免费   432篇
  国内免费   97篇
耳鼻咽喉   97篇
儿科学   71篇
妇产科学   131篇
基础医学   1205篇
口腔科学   197篇
临床医学   589篇
内科学   1387篇
皮肤病学   219篇
神经病学   491篇
特种医学   440篇
外科学   959篇
综合类   155篇
预防医学   337篇
眼科学   101篇
药学   1027篇
中国医学   198篇
肿瘤学   781篇
  2024年   6篇
  2023年   50篇
  2022年   174篇
  2021年   284篇
  2020年   129篇
  2019年   155篇
  2018年   235篇
  2017年   163篇
  2016年   280篇
  2015年   441篇
  2014年   459篇
  2013年   551篇
  2012年   865篇
  2011年   784篇
  2010年   447篇
  2009年   385篇
  2008年   500篇
  2007年   423篇
  2006年   367篇
  2005年   383篇
  2004年   326篇
  2003年   230篇
  2002年   187篇
  2001年   108篇
  2000年   119篇
  1999年   71篇
  1998年   30篇
  1997年   34篇
  1996年   24篇
  1995年   17篇
  1994年   16篇
  1993年   12篇
  1992年   16篇
  1991年   25篇
  1990年   13篇
  1989年   11篇
  1988年   13篇
  1987年   9篇
  1986年   8篇
  1985年   8篇
  1984年   3篇
  1981年   6篇
  1979年   3篇
  1976年   2篇
  1973年   1篇
  1972年   1篇
  1968年   1篇
  1967年   1篇
  1966年   2篇
  1964年   1篇
排序方式: 共有8385条查询结果,搜索用时 0 毫秒
91.
Carbon doping from a Ti precursor in TiO2 synthesized by a hydrothermal method was studied. The structural, optical and morphological study of the deposited material was carried out using X-ray diffraction, UV-vis spectroscopy and scanning electron microscopy characterization techniques. The elemental composition of the TiO2 deposited with different precursor concentrations was studied using X-ray photoelectron spectroscopy and electron dispersive X-ray spectroscopy. The amount of elemental carbon in the TiO2 matrix is found to be increased as the Ti precursor concentration is increased, which strengthens the proposed idea of carbon doping via a Ti precursor.

Interstitial carbon doping is possible directly from a Ti precursor (titanium(iv) isopropoxide) without using any other carbon source.  相似文献   
92.
Digital workflow expedites the procedure of retrofitting a surveyed crown against an existing removable partial denture (RPD). This article describes a simple and straightforward technique of digital workflow where an existing RPD is scanned as an antagonist to design the rest seat, guide plane, and height of contour of a surveyed crown.  相似文献   
93.
94.
Journal of Natural Medicines - Transforming growth factor β-induced protein (TGFBIp) is an extracellular matrix protein; its expression by several cell types is greatly increased by...  相似文献   
95.
96.
97.
ObjectiveTo evaluate the correlation between bone tunnel diameter after anterior cruciate ligament (ACL) reconstruction measured by computed tomography (CT) using multiplanar reconstruction (MPR) and stability or clinical scores.ResultsThe tibial bone tunnels for the anteromedial bundles were significantly widened at T2 compared with T1 (observer 1, 0.578 mm to 0.698 mm, p value of < 0.001; observer 2, 0.581 mm to 0.707 mm, p value of < 0.001). There was no significant correlation between the diameter at T2 and stability or clinical scores and between the interval change ratio ([T2 - T1] / T1) and stability or clinical scores (corrected p values for all were 1.0). Intraobserver agreement for measurements was excellent (> 0.8) for both observers. Interobserver agreement for measurement was excellent (> 0.8) except for the most distal portion of the femoral bone tunnel for anterior medial bundle in immediate postoperative CT, which showed moderate agreement (concordance correlation coefficient = 0.6311).ConclusionNeither the diameter nor its change ratio during interval follow-up is correlated with stability or clinical scores.  相似文献   
98.

Introduction

The acute surgical model has been trialled in several institutions with mixed results. The aim of this study was to determine whether the acute surgical model provides better outcomes for patients with acute biliary presentation, compared with the traditional emergency surgery model of care.

Methods

A retrospective review was carried out of patients who were admitted for management of acute biliary presentation, before and after the establishment of an acute surgical unit (ASU). Outcomes measured were time to operation, operating time, after-hours operation (6pm – 8am), length of stay and surgical complications.

Results

A total of 342 patients presented with acute biliary symptoms and were managed operatively. The median time to operation was significantly reduced in the ASU group (32.4 vs 25.4 hours, p=0.047), as were the proportion of operations performed after hours (19.5% vs 2.5%, p<0.001) and the median length of stay (4 vs 3 days, p<0.001). The median operating time, rate of conversion to open cholecystectomy and wound infection rates remained similar.

Conclusions

Implementation of an ASU can lead to objective differences in outcomes for patients who present with acute cholecystitis. In our study, the ASU significantly reduced time to operation, the number of operations performed after hours and length of stay.  相似文献   
99.
100.
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