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   3365篇
  免费   322篇
  国内免费   14篇
耳鼻咽喉   22篇
儿科学   161篇
妇产科学   52篇
基础医学   337篇
口腔科学   91篇
临床医学   274篇
内科学   733篇
皮肤病学   109篇
神经病学   298篇
特种医学   250篇
外国民族医学   1篇
外科学   551篇
综合类   136篇
一般理论   2篇
预防医学   241篇
眼科学   77篇
药学   156篇
中国医学   37篇
肿瘤学   173篇
  2023年   19篇
  2022年   46篇
  2021年   87篇
  2020年   45篇
  2019年   71篇
  2018年   103篇
  2017年   80篇
  2016年   79篇
  2015年   74篇
  2014年   118篇
  2013年   171篇
  2012年   239篇
  2011年   214篇
  2010年   125篇
  2009年   143篇
  2008年   174篇
  2007年   206篇
  2006年   141篇
  2005年   139篇
  2004年   121篇
  2003年   88篇
  2002年   83篇
  2001年   88篇
  2000年   86篇
  1999年   80篇
  1998年   83篇
  1997年   84篇
  1996年   60篇
  1995年   41篇
  1994年   56篇
  1993年   46篇
  1992年   47篇
  1991年   31篇
  1990年   46篇
  1989年   54篇
  1988年   51篇
  1987年   37篇
  1986年   32篇
  1985年   37篇
  1984年   23篇
  1983年   17篇
  1982年   16篇
  1981年   16篇
  1980年   18篇
  1979年   11篇
  1978年   9篇
  1977年   14篇
  1976年   17篇
  1975年   6篇
  1973年   6篇
排序方式: 共有3701条查询结果,搜索用时 31 毫秒
1.
2.
3.
Purpose

Robotic approaches have been steadily replacing laparoscopic approaches in metabolic and bariatric surgeries (MBS); however, their superiority has not been rigorously evaluated. The main goal of the study was to evaluate the 5-year utilization trends of robotic MBS and to compare to laparoscopic outcomes.

Methods

Retrospective analysis of 2015–2019 MBSAQIP data. Kruskal-Wallis test/Wilcoxon and Fisher’s exact/chi-square were used to compare continuous and categorical variables, respectively. Generalized linear models were used to compare surgery outcomes.

Results

The use of robotic MBS increased from 6.2% in 2015 to 13.5% in 2019 (N= 775,258). Robotic MBS patients had significantly higher age, BMI, and likelihood of 12 diseases compared to laparoscopic patients. After adjustment, robotic MBS patients showed higher 30-day interventions and 30-day readmissions alongside longer surgery time (26–38 min).

Conclusion

Robotic MBS shows higher intervention and readmission even after controlling for cofounding variables.

Graphical Abstract
  相似文献   
4.
Ruggieri  PM; Laub  GA; Masaryk  TJ; Modic  MT 《Radiology》1989,171(3):785-791
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.  相似文献   
5.
Acquired supravalvar membranous stenosis of the left atrioventricular valve   总被引:1,自引:0,他引:1  
Acquired supravalvar membranous stenosis of the left atrioventricular valve developed in a nine year old boy with atrioventricular discordance. The supravalvar membrane had not been present when a partial annuloplasty was performed on the left atrioventricular valve eight years before. The stenosis was relieved by operative excision of the membrane.  相似文献   
6.
BACKGROUND: In general practice, acute sinusitis is frequently diagnosed and treated with antibiotics. OBJECTIVE: This study aimed to determine the evidence for the effectiveness of antibiotic treatment in acute maxillary sinusitis in adults by assessing the methodological quality of placebo-controlled double-blind randomized trials. METHOD: An evaluation by four raters through a 35-item scoring-scale for internal and external validity of all placebo-controlled double-blind randomized trials on acute sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five trials were excluded because they were not placebo-controlled, double-blind, randomized, or were carried out in patients with chronic sinusitis or in children. The three remaining trials were performed in different populations (one in general practice) between 1973 and 1978. Only one study claimed superiority of antibiotic treatment. Different inclusion criteria and major outcome measures were used by the authors. The reliability of major outcome events was reported poorly or not at all and in two studies outcome measures were clinically inappropriate. The studies scored 30-62% of the maximum attainable score for internal validity and 10-20% for external validity. CONCLUSION: The effectiveness of antibiotic treatment in acute maxillary sinusitis in a general practice population is not based sufficiently on evidence.   相似文献   
7.
A case is described of a subarachnoid-pleural fistula developing after resection of an intrathoracic benign nerve sheath tumor near the eleventh thoracic vertebra. The fistula was demonstrated by myelography and was corrected surgically. Of 12 previously reported cases, 11 occurred after trauma and one after an operation.  相似文献   
8.
9.
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