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   20791篇
  免费   898篇
  国内免费   866篇
耳鼻咽喉   47篇
儿科学   279篇
妇产科学   83篇
基础医学   1866篇
口腔科学   31篇
临床医学   2588篇
内科学   575篇
皮肤病学   60篇
神经病学   3413篇
特种医学   1643篇
外科学   7958篇
综合类   2103篇
预防医学   334篇
眼科学   45篇
药学   826篇
  6篇
中国医学   344篇
肿瘤学   354篇
  2024年   58篇
  2023年   247篇
  2022年   552篇
  2021年   768篇
  2020年   641篇
  2019年   527篇
  2018年   572篇
  2017年   540篇
  2016年   562篇
  2015年   673篇
  2014年   1274篇
  2013年   1563篇
  2012年   1021篇
  2011年   1362篇
  2010年   1092篇
  2009年   1045篇
  2008年   1071篇
  2007年   980篇
  2006年   920篇
  2005年   822篇
  2004年   725篇
  2003年   629篇
  2002年   518篇
  2001年   477篇
  2000年   467篇
  1999年   343篇
  1998年   288篇
  1997年   296篇
  1996年   253篇
  1995年   195篇
  1994年   196篇
  1993年   203篇
  1992年   207篇
  1991年   132篇
  1990年   146篇
  1989年   122篇
  1988年   131篇
  1987年   129篇
  1986年   84篇
  1985年   94篇
  1984年   94篇
  1983年   70篇
  1982年   79篇
  1981年   52篇
  1980年   62篇
  1979年   33篇
  1978年   38篇
  1977年   50篇
  1973年   27篇
  1971年   25篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
PurposeTo assess the feasibility, safety, and efficacy of balloon-assisted delivery of ethylene vinyl alcohol copolymer (EVOH) for a range of peripheral arterial applications.Materials and MethodsSix academic medical centers entered retrospective data on 46 consecutive patients (27 men, 19 women; ages, 11–94 y; mean age, 50.3 y) who underwent 60 balloon-assisted EVOH procedures. The cohort was restricted to procedures involving peripheral, nonneural arteries 1–5.5 mm in diameter. Clinical indications included a wide range of vascular pathologic conditions (most commonly arteriovenous malformations [n = 20], renal angiomyolipomas [n = 8], and acute hemorrhage [n = 9]) and targeted visceral and musculoskeletal peripheral arteries. Data collected included sex, age, clinical indication, arterial pathology, arteries embolized, type of occlusion balloon microcatheter, type and concentration of EVOH agent, effectiveness as an embolic backstop, vessels protected, adequacy of EVOH cast penetration, catheter extraction, nontarget embolization, and complications.ResultsBalloon occlusion prevented EVOH reflux in 59 of 60 procedures (98.3%). Nontarget EVOH embolization occurred in 2 procedures (3.3%). Adequate EVOH cast penetration and complete filling of the target pathologic structure were seen in 57 of 60 procedures (95%). Balloon deflation and uneventful extraction occurred in all procedures; small EVOH fragments detached into target arteries in 2 cases. One major (1.7%) and 2 minor (3.3%) complications occurred.ConclusionsBalloon-assisted EVOH embolization of peripheral arteries is feasible, safe, effective, and versatile. The primary advantage of balloon-assisted EVOH embolization is the ability to apply more injection pressure to advance the EVOH cast assertively into the pathologic structure(s).  相似文献   
2.
Context: Persons with spinal cord injury (SCI) experience significant challenges when they access primary care and community services.

Design: A provincial summit was held to direct research, education, and innovation for primary and community care for SCI.

Setting: Toronto, Ontario, Canada.

Participants: Key stakeholders (N?=?95) including persons with SCI and caregivers, clinicians from primary care, rehabilitation, and specialized care, researchers, advocacy groups, and policy makers.

Methods: A one-day facilitated meeting that included guest speakers, panel discussions and small group discussions was held to generate potential solutions to current issues related to SCI care and to foster collaborative relationships to advance care for SCI. Perspectives on SCI management were shared by primary care, neurosurgery, rehabilitation, and members of the SCI community

Outcome Measures: Discussions were focused on five domains: knowledge translation and dissemination, application of best practices, communication, research, and patient service accessibility.

Results: Summit participants identified issues and prioritized solutions to improve primary and community care including the creation of a network of key stakeholders to enable knowledge creation and dissemination; an online repository of SCI resources, integrated health records, and a clinical network for SCI care; development and implementation of strategies to improve care transitions across sectors; implementation of effective care models and improved access to services; and utilization of empowerment frameworks to support self-management.

Conclusions: This summit identified priorities for further collaborative efforts to advance SCI primary and community care and will inform the development of a provincial SCI strategy aimed at improving the system of care for SCI.  相似文献   
3.
4.
BackgroundDuring their training, students in osteopathy regularly undergo spinal manipulation exercises. This exposes the students’ spine to unskilled gestures performed by their colleagues learning spinal manipulation. Discomfort, muscle soreness or moderate pain following spinal manipulations lasting two or three days are commonly reported. In addition, some students may have ongoing spinal musculoskeletal disease (SMSD) during their studies. The purpose of this study was to evaluate the prevalence of SMSDs and their maximum intensity in a population of osteopathy students and to determine whether individual differences exist.MethodAn exploratory cross-sectional study took place over three years. Data were collected by means of a self-administrated standardised questionnaire screening for MSD: the Nordic questionnaire.ResultsThere were 733 exploitable questionnaires, giving an average response rate of 91.5%. Average prevalence of SMSD was 98.4% during the last 12 months. Average maximum intensity perceived was 6/10 and 45% of students experienced an intense SMSD (scored between 7 and 10/10). Variation of the maximum intensity of SMSD between “before osteopathy studies” and “the last 12 months” was 1.2/10. This variation was influenced by the number of days students were manipulated during a week (p < 0.0001). On average, students underwent manipulation three days a week.ConclusionThis study confirms the important prevalence of SMSD among osteopathy students. This result led us to carry out a qualitative study for exploring students’ conceptions in health and spinal manipulative practices.  相似文献   
5.
BackgroundOur meta-analysis from 2013 showed that inserting a catheter intrathecally after an observed accidental dural puncture can reduce the need for epidural blood patch in labouring women requesting epidural analgesia. We updated our conventional meta-analysis and added a trial-sequential analysis (TSA).MethodsA systematic literature search was conducted to identify studies that compared inserting the catheter intrathecally with an epidural catheter re-site or with no intervention. The extracted data were pooled and the risk ratio (RR) and 95% confidence interval (95%CI) for the incidence of post-dural puncture headache (PDPH) was calculated, using the random effects model. A contour-enhanced funnel plot was constructed. A TSA was performed and the cumulative Z score, monitoring and futility boundaries were constructed.ResultsOur search identified 13 studies, reporting on 1653 patients, with a low risk of bias. The RR for the incidence of PDPH was 0.82 (95%CI 0.71 to 0.95) and the RR for the need for epidural blood patch was 0.62 (95%CI 0.49 to 0.79); heterogeneity of both analyses was high. The TSA showed that the monitoring or futility boundaries were not crossed, indicating insufficient data to exclude a type I error of statistical analysis. Contour-enhanced funnel plots were symmetric, suggesting no publication bias.ConclusionsConventional meta-analyses showed for the first time that intrathecal catheterisation can reduce the incidence of PDPH. However, TSA did not corroborate this finding. Despite increasing use in clinical practice there is no firm evidence on which to base a definite conclusion.  相似文献   
6.
Objective: Report measured resting energy expenditure (REE) in wheelchair rugby athletes and evaluate agreement between REE and the prediction models of Chun, Cunningham, Harris-Benedict, Mifflin, Nightingale and Gorgey, and Owen.

Design: Cohort-based validation study.

Setting. Paralympic team training camp.

Participants: Fourteen internationally competitive athletes who play wheelchair rugby, 13 of whom had cervical spinal cord injuries (SCI).

Outcome Measures: A portable metabolic analyzer was used to measure REE following an overnight fast and dual-energy X-ray absorptiometry (DXA) was used to assess lean body mass for the prediction equations.

Results: REE in the current sample was 1735?±?257?kcal?×?day?1 ranging from 1324 to 2068?kcal?×?day?1 Bhambhani Y. Physiology of wheelchair racing in athletes with spinal cord injury. Sports Med 2002;32(1):2351.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]. Bland–Altman analyses revealed negative mean bias but similar limits of agreement between measured REE and scores predicted by Chun, Cunningham, Mifflin, Nightingale and Gorgey, and Owen models in elite athletes who play wheelchair rugby.

Conclusion: Prediction models regressed on persons with and without SCI under-predicted REE of competitive wheelchair rugby athletes. This outcome may be explained by the higher REE/fat-free mass (FFM) ratio of current athletes compared to less active samples. Findings from the current study will help practitioners to determine nutrient intake needs on training days of varied intensity.  相似文献   
7.
8.
PurposeTo retrospectively evaluate the safety and effectiveness of the Covera stent graft (SG) for the treatment of dysfunctional or thrombosed arteriovenous grafts (AVGs).Materials and MethodsWithin 29 months (February 2016–August 2018), 79 patients underwent Covera SG placement in the authors’ department for the treatment of dysfunctional AVGs. Data were available for 64 patients who underwent 64 procedures, using 64 devices. Minimum follow-up was 6 months, unless reintervention occurred. Mean follow-up was 277 days (6–923 days). Treatment characteristics were 51 cases with venous-graft anastomosis (VGA) stenosis (79.7%), 13 cases of puncture zone stenosis (20.3%), 14 cases of in SG stenosis (21.9%), 8 cases of pseudoaneurysm treatment (12.5%) (1 treatment area might have had more than 1 characteristic). Thirty-six patients presented with thrombosis (56.2%), and 31 of 64 case were de novo treatment areas (48.4%). Primary outcome measurements were technical success and post-intervention primary patency (PIPP) at 6 months, whereas secondary outcome measurements included factors influencing primary outcome.ResultsTechnical success was 100%. Median PIPP was 336 days, and 73.6% of treatment areas were patent at 6 months. There were no significant differences in terms of PIPP when de novo treatment areas were compared with restenotic areas (519 vs. 320 days, respectively; P = .1); patients who presented with versus those who presented without thrombosis (320 vs. 583 days, respectively; P = .07); puncture zone stenosis or elsewhere (329 vs. 686 days, respectively; P = .52); and VGA stenosis or elsewhere (336 vs. 335 days, respectively; P = .9).ConclusionsUse of the Covera SG for AVG treatment was safe and effective in every type of treatment area presented in this retrospective analysis.  相似文献   
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