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   21902篇
  免费   1242篇
  国内免费   181篇
耳鼻咽喉   241篇
儿科学   384篇
妇产科学   390篇
基础医学   2543篇
口腔科学   618篇
临床医学   1470篇
内科学   5997篇
皮肤病学   351篇
神经病学   1230篇
特种医学   727篇
外科学   4213篇
综合类   106篇
预防医学   630篇
眼科学   257篇
药学   1255篇
中国医学   36篇
肿瘤学   2877篇
  2023年   150篇
  2022年   253篇
  2021年   544篇
  2020年   310篇
  2019年   386篇
  2018年   490篇
  2017年   406篇
  2016年   509篇
  2015年   560篇
  2014年   712篇
  2013年   782篇
  2012年   1279篇
  2011年   1373篇
  2010年   784篇
  2009年   656篇
  2008年   1236篇
  2007年   1274篇
  2006年   1295篇
  2005年   1279篇
  2004年   1229篇
  2003年   1198篇
  2002年   1129篇
  2001年   432篇
  2000年   473篇
  1999年   484篇
  1998年   284篇
  1997年   227篇
  1996年   217篇
  1995年   187篇
  1994年   150篇
  1993年   184篇
  1992年   317篇
  1991年   270篇
  1990年   232篇
  1989年   211篇
  1988年   210篇
  1987年   192篇
  1986年   171篇
  1985年   164篇
  1984年   135篇
  1983年   93篇
  1982年   70篇
  1981年   71篇
  1979年   65篇
  1978年   67篇
  1977年   52篇
  1975年   57篇
  1974年   55篇
  1972年   44篇
  1969年   52篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
We report a case of a diaphragmatic hernia after a heart transplant operation. A 43-year-old woman, who underwent orthotropic heart transplantation for hypertrophic cadiomyopathy two year earlier, presented with vomiting and epigastric pain. A computed tomography scan showed that the stomach and transverse colon were dislocated in the left thoracic cavity. We diagnosed left diaphragmatic hernia incarceration and performed laparoscopic repair of the diaphragmatic hernia. A 12 × 8 cm diaphragmatic defect was found intraoperatively on the ventrolateral aspect of the left diaphragm, and the stomach with volvulus had herniated into the thorax through the defect. The hernia was considered to be iatrogenic. The diaphragmatic defect was large, and the diaphragm was thinning. We closed the defect by mesh repair. Laparoscopic mesh repair of the diaphragmatic hernia could be performed safely and with minimal invasiveness.  相似文献   
5.

Background

There were few studies assessed the postoperative sarcopenia in patients with cancers. The objective of present study was to assess whether postoperative development of sarcopenia could predict a poor prognosis in patients with adenocarcinoma of esophagogastric junction, (AEG) and upper gastric cancer (UGC).

Methods

Patients with AEG and UGC who were judged as non-sarcopenic before surgery were reassessed the presence of postoperative development of sarcopenia 6 months after surgery. Patients were divided into the development group or non-development group, and clinicopathological factors and prognosis between these two groups were analyzed.

Results

The 5-year overall survival rates were significantly poorer in the development group than non-development group (68.0% vs. 92.6%, P?=?0.0118). Multivariate analyses showed that postoperative development of sarcopenia was an independent prognostic factor for poor overall survival (P?=?0.0237).

Conclusions

Postoperative development of sarcopenia was associated with a poor prognosis in patients with AEG and UGC.  相似文献   
6.
7.
BackgroundVenoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used as a life-saving therapy for patients with cardiovascular collapse, but identifying patients unlikely to benefit remains a challenge.Methods and ResultsWe created the RESCUE registry, a retrospective, observational registry of adult patients treated with VA-ECMO between January 2007 and June 2017 at 3 high-volume centers (Columbia University, Duke University, and Washington University) to describe short-term patient outcomes. In 723 patients treated with VA-ECMO, the most common indications for deployment were postcardiotomy shock (31%), cardiomyopathy (including acute heart failure) (26%), and myocardial infarction (17%). Patients frequently suffered in-hospital complications, including acute renal dysfunction (45%), major bleeding (41%), and infection (33%). Only 40% of patients (n = 290) survived to discharge, with a minority receiving durable cardiac support (left ventricular assist device [n = 48] or heart transplantation [n = 7]). Multivariable regression analysis identified risk factors for mortality on ECMO as older age (odds ratio [OR], 1.26; 95% confidence interval [CI], 1.12–1.42) and female sex (OR, 1.44; 95% CI, 1.02–2.02) and risk factors for mortality after decannulation as higher body mass index (OR 1.17; 95% CI, 1.01-1.35) and major bleeding while on ECMO support (OR, 1.92; 95% CI, 1.23–2.99).ConclusionsDespite contemporary care at high-volume centers, patients treated with VA-ECMO continue to have significant in-hospital morbidity and mortality. The optimization of outcomes will require refinements in patient selection and improvement of care delivery.  相似文献   
8.
9.

Objective

This study assessed the association between the timing of first epinephrine administration (EA) and the neurological outcomes following out-of-hospital cardiac arrests (OHCAs) with both initial shockable and non-shockable rhythms.

Methods

This was a post-hoc analysis of a multicenter prospective cohort study (SOS-KANTO 2012), which registered OHCA patients in the Kanto region of Japan from January 2012 to March 2013. We included consecutive adult OHCA patients who received epinephrine. The primary result included 1-month favorable neurological outcomes defined as cerebral performance category (CPC) 1 or 2. Secondary results included 1-month survival and return of spontaneous circulation (ROSC) after arrival at the hospital. Multivariable logistic regression analysis determined the association between delay per minute of the time from call to first EA in both pre- or in-hospital settings and outcomes.

Results

Of the 16,452 patients, 9344 were eligible for our analyses. In univariable analysis, the delay in EA was associated with decreased favorable neurological outcomes only when the initial rhythm was a non-shockable rhythm. In multivariable analyses, delay in EA was associated with decreased ROSC (adjusted odds ratio [OR] for one minute delay, 0.97; 95% confidence interval [CI], 0.96–0.98) and 1-month survival (adjusted OR, 0.95; 95% CI, 0.92–0.97) when the initial rhythm was a non-shockable rhythm, whereas during a shockable rhythm, delay in EA was not associated with decreased ROSC and 1-month survival.

Conclusions

While assessing the effectiveness of epinephrine for OHCA, we should consider the time-limited effects of epinephrine. Additionally, consideration of early EA based on the pathophysiology is needed.  相似文献   
10.
BackgroundAdjacent vertebral fracture (AVF) is a major complication following Balloon Kyphoplasty (BKP). There is no scoring system for predicting AVF using only preoperative elements. The purposes of this study were to develop a scoring system for predicting early AVF after BKP based on preoperative factors and to investigate the appropriate surgical indication for BKP.MethodsOf 220 patients who underwent BKP at a single institution since 2011, 65 patients over the age of 60 who had undergone a standing whole spine X-ray preoperatively were enrolled. Factors affecting the occurrence of early AVF were examined. A scoring system was created consisting of the factors exhibiting significant differences, and the correlation between the total score and the incidence of early AVF was investigated.ResultsTwenty of the 65 patients (30.8%) had early AVF. In a univariate analysis, age, previous vertebral fracture, pelvic tilt, and Local kyphosis significantly influenced early AVF. In a multivariate logistic regression analysis, age had an odds ratio of 1.136 (95% CI 1.001–1.289), previous vertebral fractures 4.181 (1.01–17.309), and Local kyphosis 1.103 (1.021–1.191). The scoring system was set as follows: ①Age (<75 years: 0 points(P), 75years≦: 1P), ②The number of previous vertebral fractures (0: 0 P, 1: 1P, 2: 2P, 3 or more: 3P), and ③Local kyphosis (<10°: 0P, 10°≦: 1P). There was a correlation between the total score and the incidence of early AVF (r = 0.812, 1P = 0.05). The incidence of early AVF was 6.4% (2 cases/31 cases) for a score of ≦1P and 54.5% (18 cases/33 cases) for a score of ≧2P.ConclusionsThere was a correlation between the total score and the incidence of early AVF. A score of 1 point or less may represent the appropriate surgical indication for BKP.  相似文献   
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