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   4781篇
  免费   264篇
  国内免费   28篇
耳鼻咽喉   60篇
儿科学   93篇
妇产科学   93篇
基础医学   473篇
口腔科学   142篇
临床医学   334篇
内科学   991篇
皮肤病学   134篇
神经病学   168篇
特种医学   295篇
外国民族医学   4篇
外科学   1105篇
综合类   120篇
一般理论   4篇
预防医学   316篇
眼科学   114篇
药学   335篇
中国医学   24篇
肿瘤学   268篇
  2024年   2篇
  2023年   45篇
  2022年   151篇
  2021年   251篇
  2020年   136篇
  2019年   202篇
  2018年   196篇
  2017年   120篇
  2016年   154篇
  2015年   170篇
  2014年   258篇
  2013年   268篇
  2012年   374篇
  2011年   432篇
  2010年   248篇
  2009年   185篇
  2008年   297篇
  2007年   329篇
  2006年   269篇
  2005年   224篇
  2004年   188篇
  2003年   193篇
  2002年   152篇
  2001年   29篇
  2000年   29篇
  1999年   31篇
  1998年   15篇
  1997年   10篇
  1996年   16篇
  1995年   9篇
  1994年   7篇
  1993年   3篇
  1992年   5篇
  1991年   6篇
  1990年   4篇
  1989年   3篇
  1988年   9篇
  1987年   5篇
  1986年   2篇
  1984年   5篇
  1981年   4篇
  1980年   2篇
  1979年   3篇
  1976年   7篇
  1975年   3篇
  1974年   3篇
  1973年   4篇
  1972年   4篇
  1969年   3篇
  1921年   1篇
排序方式: 共有5073条查询结果,搜索用时 15 毫秒
61.
62.

Background

Laparoscopic cholecystectomy (LC) is the standard operative intervention for gallbladder disease. Complications may necessitate conversion to an open cholecystectomy (OC). This study aims to determine the cost-consequences of laparoscopic-to-open conversion using a nationally-representative sample.

Methods

Using the National Inpatient Sample (2007–2011), adult patients undergoing emergent LC were identified. Patients undergoing secondary-conversion to OC were subsequently identified. Multivariable regression analyses, accounting for differences in propensity-quintile, mortality, length of stay, and hospital-level factors were then performed to assess for differences in the odds of conversion and total predicted mean costs per index-hospitalization.

Results

Of 225,805 observations, conversion to open occurred in 1.86% (n?=?4203) of cases. Increased age, African-American ethnicity, public-insurance and teaching-hospital status were associated with a higher likelihood of conversion (p?<?0.05) after risk-adjustment. Risk-adjusted odds of conversion increased by 34% (95%CI:1.33–1.36) for each day surgery was delayed. Risk-adjusted costs, were 259% higher (absolute-difference $23,358,p?<?0.05) with conversion. Mortality was higher amongst patients undergoing conversion to open (4.98% vs 0.34%,p?<?0.001).

Conclusion

Patients undergoing conversion from laparoscopic to open cholecystectomy are at an increased risk of receiving disparate care and increased mortality.  相似文献   
63.
Aortic arch aneurysm is a relatively rare entity in cardiac surgery. Repair of such aneurysms, either in isolation or combined with other cardiac procedures, remains a challenging task. The need to produce a relatively bloodless surgical field with circulatory arrest, while at the same time protecting the brain, is the hallmark of this challenge. However, a clear understanding of the topic allows a better and less morbid approach to such a complex surgery.Literature has shown the advantage of selective cerebral perfusion techniques in comparison with only circulatory arrest. Ability to perfuse the brain has allowed circulatory arrest temperatures at moderate hypothermia without the need for deep hypothermia. Even though cannulation site selection appears to be a minor issue, literature has shown that the subclavian/axillary route has the best outcomes and that femoral cannulation should only be reserved for no access patients. Although different techniques for arch anastomosis have been described, we routinely perform the distal first technique as we find it to be less cumbersome and easiest to reproduce.In this review our aim is to outline a systematic approach to aortic arch surgery. Starting with indications for intervention and proceeding with approaches on site of cannulation, approaches to brain protection with hypothermia and selective cerebral perfusion and finally surgical steps in performing the distal and arch vessels anastomosis.  相似文献   
64.
Transcatheter aortic valve replacement (TAVR) has been increasingly used to treat patients with symptomatic aortic stenosis. Despite improvements in valve deployment, patients that have undergone TAVR are at high risk for major adverse events following the procedure. Blood cell numbers, platelet function, and biomarkers of systemic inflammation were analyzed in 58 patients undergoing TAVR with the Edward’s SAPIEN valve. Following valve deployment, platelet count and agonist-induced platelet activity declined and plasma markers of systemic inflammation (interleukin-6 and S100A8/A9) increased. Baseline platelet activity prior to TAVR correlated with perioperative changes plasma interleukin-6 levels. Moreover, perioperative changes in plasma inflammatory markers predicted the decline in platelet count in the days following the TAVR procedure. Additionally, a significant effect of gender on platelet count following TAVR and was observed. Finally, post-procedural mortality was associated with sustained thrombocytopenia after TAVR. Our findings suggest that TAVR elicits a thromboinflammatory state that may contribute to post-procedural thrombocytopenia. Importantly, our results add to the growing body of literature that suggests the thromboinflammatory changes that occur early after TAVR may predict long-term outcomes.  相似文献   
65.
66.
67.
68.
Intragastric balloon (IGB) is one of the available options for the management of morbid obesity. The procedure is generally safe and of moderate efficacy in most of the cases. One of the reported complications of IGB is gastric perforation. The management of this complication is classically surgical. To our knowledge, conservative management for gastric perforation secondary to IGB has not been reported. A 27-year-old female patient presented with sudden abdominal pain in the left upper quadrant, 2 months after having an IGB placed. The provisional diagnosis was gastric perforation. Balloon extraction was performed and a conservative management of the gastric perforation was pursued successfully. We therefore propose that this sort of management might be adopted in carefully selected cases.  相似文献   
69.
Abstract

Objective: Gastric distention and perforation are possible results in a preterm newborn with esophageal atresia and distal tracheoesophageal fistula, especially when there is a need for mechanical ventilatory support. The results of the reported cases treated with emergency thoracotomy and fistula ligation after gastrostomy are not very satisfactory. Sometimes simple temporary solutions can be useful for stabilization and allow safety for required surgical treatment for later.

Patient and methods: Two preterm newborns with esophageal atresia and distal tracheoesophageal fistula complicated by gastric perforation were reported.

Results: Both of the patients were initially treated with a simple peritoneal drainage and, then the definitive operations were performed without any problem in stabilized patients.

Conclusion: Performing fistula ligation or occlusion as an initial treatment in patients with impaired cardiac and respiratory functions may worsen the status of the patient. In such cases, it could be better to perform simple interventions first to facilitate subsequent treatments.  相似文献   
70.
Pre-Fontan coil closure of aorto-pulmonary collaterals decreases single-ventricle volume load and improves outcome. Coiling of right and left internal mammary arteries may present a challenge to cardiothoracic surgery teams caring for these patients when future coronary artery bypass grafting is needed for SV patients. The goal of this study was to determine the frequency of internal mammary artery coil closure in SV patients in a single tertiary care center. A retrospective review of all pediatric single-ventricle patients who underwent cardiac catheterization between March 2009 and October 2015 at Rush Center for Congenital Heart Disease was performed. Fifty-one patients’ charts were reviewed. Twenty-five patients received coil closure of one or more internal mammary artery (coil group) and 26 received no coil closure (no-coil group). In the coil group, 21 (84 %) had their collateral vessels coiled in the pre-Fontan period and 4 (16 %) had their vessels coiled in the post-Fontan period. In the coil group, 18 (72 %) had their right internal mammary artery coiled and 7 (28 %) had both right and left internal mammary arteries coiled. None of the coil group had isolated coil closure of the left internal mammary artery. This study is the first to verify the frequency of right and/or left internal mammary artery coil closure in SV patients and the potential impact on future coronary artery bypass grafting. Extensive peri-Fontan coiling of the internal mammary arteries presents a significant potential challenge for subsequent management of SV patients as older adults.  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