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   178752篇
  免费   11953篇
  国内免费   702篇
耳鼻咽喉   2529篇
儿科学   4895篇
妇产科学   3438篇
基础医学   23217篇
口腔科学   3547篇
临床医学   17511篇
内科学   38217篇
皮肤病学   2802篇
神经病学   18059篇
特种医学   6238篇
外国民族医学   13篇
外科学   26508篇
综合类   2315篇
现状与发展   3篇
一般理论   201篇
预防医学   13456篇
眼科学   4779篇
药学   11599篇
中国医学   203篇
肿瘤学   11877篇
  2023年   644篇
  2022年   800篇
  2021年   2866篇
  2020年   1770篇
  2019年   2896篇
  2018年   3407篇
  2017年   2461篇
  2016年   2867篇
  2015年   3462篇
  2014年   5125篇
  2013年   7900篇
  2012年   11407篇
  2011年   12280篇
  2010年   6851篇
  2009年   6319篇
  2008年   11565篇
  2007年   12326篇
  2006年   11829篇
  2005年   12179篇
  2004年   11572篇
  2003年   11049篇
  2002年   10650篇
  2001年   1498篇
  2000年   1150篇
  1999年   1606篇
  1998年   2343篇
  1997年   2029篇
  1996年   1708篇
  1995年   1593篇
  1994年   1434篇
  1993年   1360篇
  1992年   1062篇
  1991年   973篇
  1990年   850篇
  1989年   825篇
  1988年   845篇
  1987年   731篇
  1986年   848篇
  1985年   927篇
  1984年   1232篇
  1983年   1182篇
  1982年   1653篇
  1981年   1524篇
  1980年   1429篇
  1979年   796篇
  1978年   918篇
  1977年   810篇
  1976年   720篇
  1975年   569篇
  1974年   587篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
51.

Background

Most elderly trauma patients suffer blunt head injury and many utilize antithrombotic (AT) medications. The utility of delayed CT-head (D-CTH) in neurologically intact elderly patients using AT who have an intracranial hemorrhage (ICH) on presentation is unknown. We hypothesized that D-CTH would not alter clinical management and aimed to evaluate the role of D-CTH in this population.

Methods

A retrospective cohort study was performed. Patients ≥65 years sustaining blunt head injuries from January 2010 to July 2017 were identified using our level 1 trauma center database. AT-patients presenting with ICH who underwent D-CTH were included. Patients with worsened ICH were compared to those with stable to improved ICH on D-CTH. AT-patients were compared to a cohort of non-AT patients. Fisher’s Exact and Mann-Whitney U tests were utilized and a power analysis conducted.

Results

137?A?T and 34 non-AT patients were identified. There was no difference in hemorrhage progression or appearance of new ICH. No patient had a change in management from D-CTH in either cohort. AT-patients were slightly older (p?<?0.001), but cohorts were otherwise similar.50 AT-patients with worsened ICH were compared to 87 with stable ICH. There was no difference in cohort demographics. Hemorrhage progression did not vary with type of AT used but did increase if multiple types of synchronous ICH were present (p?<?0.001).

Conclusions

Our data supports abstaining from routine D-CTH of elderly ICH patients with an intact neurologic examination who are utilizing aspirin, clopidogrel or warfarin. Conclusions cannot be drawn regarding new oral anticoagulants (NOACs) given low enrollment. Further multicenter study is required to provide adequate power and detect small levels of management change.  相似文献   
52.
Congenital heart disease is a rare but important finding in adults who experience sudden death. Examination of the congenitally malformed heart has historically been considered esoteric and best left to those with expertise. The Cardiac Risk in the Young cardiovascular pathology laboratory based at St George's University of London has now received over 6,000 cases. Of these, 21 congenitally malformed hearts were retained for research and educational purposes. Hearts were assessed using sequential segmental analysis, and causes of death were adjudicated based on thorough macroscopic examination and histology. Congenital malformations that were encountered included atrial septal defects, ventricular septal defects, tetralogy of Fallot, and transposition of the great arteries in both its regular and congenitally corrected variants. Findings also included hearts with mirror-imaged and isomeric atrial appendages. Direct causes of death included myocardial fibrosis, pulmonary hypertension, and hemorrhage. A small but notable proportion did not reveal a substrate for arrhythmia, raising the question of whether the terminal event was due to the congenital heart disease itself, or an underlying channelopathy. Here, we demonstrate the value of simple sequential segmental analysis in describing and categorizing the cases, with the concept of the “morphological method” serving to identify the distinguishing features of the cardiac components. Clin. Anat. 33:394–404, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
53.
54.
55.
56.
Background: Little is known of stroke outcomes in low- and middle-income countries with limited formal stroke rehabilitation services and of homebased-stroke services delivered within the primary health care (PHC) context by community health workers (CHWs).

Objectives: To describe and analyze the outcomes of patients with stroke from a rural PHC setting in the Western Cape, South Africa.

Methods: In a longitudinal survey, 93 stroke patients, referred to home and community-based care services (HCBC) between June 2015 and December 2017, were assessed at baseline, one month and three months. Changes in function (Barthel Index (BI)), caregiver strain (Caregiver Strain Index (CSI)), impact of environmental factors and satisfaction with stroke care were measured.

Results: HCBC was delayed, fragmented and brief (median session duration 20 minutes (IQR 15.0–30.0)). Although function improved significantly, dependence remained high: median BI score changed from 40.0 (IQR 15.0–70.0) to 62.5 (IQR 30.0–81.25) (p = .019). A third (33.0% (30/91)) of caregivers initially experienced strain and the median CSI score remained 3.0 (IQR 0.0–7.0) (p = .672). Overall, patient and caregiver satisfaction with HCBC was low with only 46.9% (31/66) of caregivers and 17.4% (12/69) of patients satisfied with all aspects of care. Only 47.6% of assistive product needs were met. Environmental factors negatively impacted on patient function and caregiving.

Conclusions: Clinical practice pathways and referral guidelines should be developed for the HCBC platform. Specific training of CHWs, focusing on how to educate, support and train family caregivers, provide assistive devices and refer to health services is needed.  相似文献   

57.
Anatomical understanding of the peritrochanteric space and abductor insertions has been well documented in the literature. Extrapolating this knowledge to perform a “successful” abductor tendon repair has led to controversy over the best method to achieve a durable, stable repair and improve patient outcomes. I feel that the debate in the hip over single- versus double-row fixation is only beginning and we are in for a ride to uncover the best method, as we have with the shoulder over the last 15 years. What is best? Single or double row?  相似文献   
58.
59.
60.
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