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   6837篇
  免费   426篇
  国内免费   12篇
耳鼻咽喉   41篇
儿科学   277篇
妇产科学   251篇
基础医学   777篇
口腔科学   62篇
临床医学   1319篇
内科学   1187篇
皮肤病学   108篇
神经病学   504篇
特种医学   129篇
外科学   583篇
综合类   71篇
一般理论   9篇
预防医学   1042篇
眼科学   149篇
药学   313篇
  1篇
中国医学   5篇
肿瘤学   447篇
  2023年   43篇
  2022年   68篇
  2021年   135篇
  2020年   75篇
  2019年   148篇
  2018年   151篇
  2017年   143篇
  2016年   145篇
  2015年   141篇
  2014年   212篇
  2013年   344篇
  2012年   479篇
  2011年   542篇
  2010年   281篇
  2009年   239篇
  2008年   500篇
  2007年   498篇
  2006年   490篇
  2005年   452篇
  2004年   434篇
  2003年   423篇
  2002年   411篇
  2001年   48篇
  2000年   46篇
  1999年   54篇
  1998年   66篇
  1997年   76篇
  1996年   70篇
  1995年   51篇
  1994年   41篇
  1993年   49篇
  1992年   31篇
  1991年   14篇
  1990年   27篇
  1989年   29篇
  1988年   27篇
  1987年   17篇
  1986年   10篇
  1985年   17篇
  1984年   22篇
  1983年   19篇
  1982年   29篇
  1981年   16篇
  1980年   23篇
  1979年   13篇
  1978年   21篇
  1977年   15篇
  1976年   10篇
  1975年   15篇
  1966年   6篇
排序方式: 共有7275条查询结果,搜索用时 31 毫秒
101.
In a previous study (Simmons-Stern, Budson & Ally, 2010), we found that patients with Alzheimer's disease (AD) better recognized visually presented lyrics when the lyrics were also sung rather than spoken at encoding. The present study sought to further investigate the effects of music on memory in patients with AD by making the content of the song lyrics relevant for the daily life of an older adult and by examining how musical encoding alters several different aspects of episodic memory. Patients with AD and healthy older adults studied visually presented novel song lyrics related to instrumental activities of daily living (IADL) that were accompanied by either a sung or a spoken recording. Overall, participants performed better on a memory test of general lyric content for lyrics that were studied sung as compared to spoken. However, on a memory test of specific lyric content, participants performed equally well for sung and spoken lyrics. We interpret these results in terms of a dual-process model of recognition memory such that the general content questions represent a familiarity-based representation that is preferentially sensitive to enhancement via music, while the specific content questions represent a recollection-based representation unaided by musical encoding. Additionally, in a test of basic recognition memory for the audio stimuli, patients with AD demonstrated equal discrimination for sung and spoken stimuli. We propose that the perceptual distinctiveness of musical stimuli enhanced metamemorial awareness in AD patients via a non-selective distinctiveness heuristic, thereby reducing false recognition while at the same time reducing true recognition and eliminating the mnemonic benefit of music. These results are discussed in the context of potential music-based memory enhancement interventions for the care of patients with AD.  相似文献   
102.
Abstract

Neuropsychological examination of children and adolescents involved in personal injury litigation provides important information about a brain-based cognitive impairment; about its dimensions, its potential for remediation, and its probable causes. Information from neuropsychological assessments is useful in personal injury actions involving children and adolescents when neuropsychologists apply statistical decision-making and inferencing to test profiles so as to provide triers of fact with informed clinical opinions about previous, present, and future cognitive development.  相似文献   
103.

Background

Critical hand ischemia owing to below-the-elbow atherosclerotic occlusive disease is relatively uncommon. The aim of this study was to examine the outcomes in patients presenting with critical ischemia owing to below-the-elbow arterial atherosclerotic disease who underwent nonoperative and operative management.

Methods

A database of patients undergoing operative and nonoperative management for symptomatic below-the-elbow atherosclerotic disease between 2006 and 2016 was retrospectively queried. Patients with critical ischemia (tissue loss and rest pain) were identified. Three management groups were identified: no revascularization (None), endovascular revascularization (Endo), and open revascularization by bypass (Bypass). Patients with acute embolism, active vasculitis, end-stage renal disease, ipsilateral dialysis access complications of steal, and ipsilateral trauma were excluded.

Results

One hundred eight patients (56% male; average age, 59 years) presented with symptomatic below-the-elbow disease: 93% presented with digital ulceration and the remainder with rest pain. Eighty-one percent had diabetes and 41% had chronic renal insufficiency (not on dialysis). All underwent catheter-based angiography. Fifty-three patients (49%) had no intervention and subsequently were committed to wound care; 26 of these required no further intervention, 10 had an interval palmar sympathectomy, and 17 underwent either a phalanx or digital amputation. Thirty-four patients (31%) underwent an endovascular intervention with a median of 1.5 vessels (ulnar, radial, or interosseous arteries) intervened on. Technical success was achieved in 29 patients (85%). Of the five technical failures, two went on to bypass, one had a focal endarterectomy and patch angioplasty, and one was treated conservatively. Ten patients in the Endo group required either a phalanx or digital amputation. Twenty-one patients (19%) underwent a saphenous vein bypass (reversed or nonreserved) to the radial in 12 and the ulnar in 11 limbs. In follow-up, 11 patients underwent open or endovascular intervention to maintain patency of the bypass. There were nine phalanx or digital amputations in the Bypass group. No below-the-elbow or above-the-elbow amputations were performed within 30 days. The wound healing rate without amputation was 78% (85 of 108). The predictors of wound healing were technical success of the revascularization, intact palmar arch and presence of digital run-off. The presence of an incomplete arch and poor digital run-off were associated with a phalanx or digital amputation.

Conclusions

Upper extremity interventions for critical ischemia are associated with a high rate of success. Major amputations are rare and the many can be treated nonoperatively. In appropriately selected patients, both endovascular and open interventions have a high rate of success.  相似文献   
104.
105.
106.
107.
IntroductionThe purpose of this study was to investigate the impact that geographic ancestry and body size have on ultrasonographic measurements of the ulnar nerve size measured at the elbow.Materials and methodsWe performed anthropometric measurements of body size and ultrasonographic measurements of the ulnar nerve at the elbow on 13 Vietnamese and 24 European participants. Regression analysis was used to determine the effect of body size and geographic ancestry on ulnar nerve size.ResultsBMI had the greatest impact on ulnar nerve size. The short axis diameter was least resilient, and the long axis diameter was the most resilient to the effects of body size and geographic ancestry.DiscussionThe long axis diameter has an apparent immunity to the influences of overall body size, arm size, or geographic ancestry and has the most potential as a sensitive discriminator between normal nerves and nerves affected by ulnar neuropathy at the elbow.  相似文献   
108.
A cohort design was used to determine uptake and drop out of 213 HIV-exposed infants eligible for Early Infant Diagnosis (EID) of HIV. To explore service providers and care givers knowledge, attitudes and perceptions of the EID process, observations and in-depth interviews were conducted. 145 (68%) infants enrolled after 2 months of age. 139 (65%) dropped out before follow up to 18 months old. 60 (43%) drop outs occurred within 2 months of enrolment. Maternal factors associated with infant drop out were maternal loss to follow up (48 [68%] vs. 8 [20%], P < 0.001) and younger maternal age (27.2 vs. 30.1 years, P = 0.033). Service providers and caregivers had inadequate training, knowledge and understanding of EID. Poverty and lack of social support were challenges in accessing EID services. EID should be more closely aligned within PMTCT services, integrated with routine mother and child health (MCH) activities and its implementation more closely monitored.  相似文献   
109.
Prior clinical research supports the effectiveness of cancer support groups for cancer patients and their families, yet African-American families continue to be underrepresented in cancer support groups and in cancer clinical research studies. In order to fill this gap, we developed and evaluated a culturally adapted family support group for African-American families coping with parental cancer. We encountered unexpected challenges in overcoming barriers to recruitment, partnering with oncology providers, and building trust with the African-American community and African-American families coping with parental cancer. We describe actions taken during the two phases of this study and lessons learned along the way about recruiting and engaging African-American families in cancer support group studies, partnering with oncology providers, networking with the African-American community, and the importance of demonstrating cultural sensitivity to overcome the understandable historical legacy of mistrust.  相似文献   
110.
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