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   9142篇
  免费   493篇
  国内免费   34篇
耳鼻咽喉   12篇
儿科学   44篇
妇产科学   168篇
基础医学   607篇
口腔科学   118篇
临床医学   1085篇
内科学   2537篇
皮肤病学   86篇
神经病学   1515篇
特种医学   246篇
外科学   800篇
综合类   146篇
预防医学   1542篇
眼科学   34篇
药学   321篇
  1篇
中国医学   71篇
肿瘤学   336篇
  2023年   610篇
  2022年   979篇
  2021年   1000篇
  2020年   992篇
  2019年   478篇
  2018年   358篇
  2017年   386篇
  2016年   400篇
  2015年   291篇
  2014年   873篇
  2013年   494篇
  2012年   309篇
  2011年   223篇
  2010年   433篇
  2009年   401篇
  2008年   181篇
  2007年   153篇
  2006年   131篇
  2005年   103篇
  2004年   86篇
  2003年   84篇
  2002年   77篇
  2001年   61篇
  2000年   64篇
  1999年   93篇
  1998年   72篇
  1997年   66篇
  1996年   65篇
  1995年   23篇
  1994年   20篇
  1993年   27篇
  1992年   23篇
  1991年   21篇
  1990年   21篇
  1989年   20篇
  1988年   8篇
  1987年   8篇
  1985年   5篇
  1984年   4篇
  1983年   2篇
  1982年   6篇
  1981年   4篇
  1980年   5篇
  1979年   1篇
  1978年   2篇
  1977年   2篇
  1976年   2篇
  1972年   1篇
  1969年   1篇
排序方式: 共有9669条查询结果,搜索用时 375 毫秒
1.
2.
3.
4.
Copyright     
  相似文献   
5.
In the United States, approximately 400,000 patients with acute stroke are discharged annually to inpatient rehabilitation facilities (IRFs) or skilled nursing facilities (SNFs). Typically, IRFs provide time-intensive therapy for an average of 2-3 weeks, whereas SNFs provide more moderately intensive therapy for 4-5 weeks. The factors that influence discharge to an IRF or SNF are multifactorial and poorly understood. The complexity of these factors in combination with subjective clinical indications contributes to large variations in the use of IRFs and SNFs. This has significant financial implications for health care expenditure, given that stroke rehabilitation at IRFs costs approximately double that at SNFs. To control health care spending without compromising outcomes, the Institute of Medicine has stated that policy reforms that promote more efficient use of IRFs and SNFs are critically needed. A major barrier to the formulation of such policies is the highly variable and low-quality evidence for the comparative effectiveness of IRF- vs SNF-based stroke rehabilitation. The current evidence is limited by the inability of observational data to control for residual confounding, which contributes to substantial uncertainty around any magnitude of benefit for IRF- vs SNF-based care. Furthermore, it is unclear which specific patients would receive the most benefit from each setting. A randomized controlled trial addresses these issues, because random treatment allocation facilitates an equitable distribution of measured and unmeasured confounders. We discuss several measurement, practical, and ethical issues of a trial and provide our rationale for design suggestions that overcome some of these issues.  相似文献   
6.
Background. There is a lack of standardized protocols and clinical trials for older adults involving neuropsychological factors in the literature. Furthermore, no systematic review has been published investigating this theme.Purpose. The purpose of this systematic review was to analyze the effects of aquatic physical exercise on neuropsychological factors in older adults.Methods. A systematic review (CRD42020176899) was conducted, using articles from Pubmed, Web of Science, Scopus, Cochrane Library, Science Direct and Medline published until March 2020 (without limit of previous year). Eligibility criteria for selecting studies were: clinical trials; samples with a mean age of 65 years old and over; articles involving aquatic physical exercise; and presenting neuropsychological outcomes (behavior, cognition, psychological, mental health).Results and discussion. The search yielded 801 records and 16 studies were included, totaling: 1707 older adults, with a mean age of 71.3 years old (range of mean ages in the studies: 65.3 to 88.4 years old) and a predominance of women. Aquatic physical exercise showed positive results in the mental component of quality of life, fear of falling, mood, anxiety and internal health locus of control in healthy sedentary older adults. Only one study out of 5 carried out with older adults with osteoarthritis showed improvements in psychological well-being after aquatic intervention. Older women with osteopenia or osteoporosis showed improvements in the mental component of quality of life. Studies on dementia showed a significant improvement in behavioral and psychological symptoms after aquatic intervention and no effect on depressive symptoms.Conclusion. Based on the results of this systematic review, aquatic physical exercise has positive effects on quality of life, fear of falling, cognitive functions, mood, anxiety and internal health locus of control in sedentary community-dwelling older people. It can be a great resource for carrying out physical activities in this population.  相似文献   
7.
8.
9.
ObjectiveTo investigate the bidirectional relationship by determining whether baseline sleep quality predicts pain intensity and whether baseline pain intensity predicts sleep quality in older individuals with chronic low back pain (LBP).DesignA prospective longitudinal cohort study with a 6-month follow-up period.SettingCommunity.ParticipantsOlder adults with LBP aged 60 years or older (N=215).InterventionNot applicable.Main Outcome MeasuresData collection occurred at baseline and at 6 months. Pain intensity and sleep quality were measured in both time points of assessment using the numeric pain rating scale (range, 0-10) and the Pittsburg Sleep Quality Index. At baseline, we also collected information on demographic anthropometric variables, cognitive status, depression, and comorbidities. Multivariable linear regression analyses adjusted for potential covariates were performed.ResultsA total of 215 individuals with LBP were recruited. Poor sleep quality at baseline predicted high pain intensity at 6 months (β coefficient, 0.18; 95% confidence interval [CI], 0.07-0.30). High pain intensity at baseline predicted poor sleep quality 6 months later (β coefficient, 0.14; 95% CI, 0.01-0.26).ConclusionOur findings give some support to the bidirectional relationship between pain and sleep quality in older individuals with LBP. This bidirectional relationship may be used as prognostic information by clinicians when managing patients with LBP.  相似文献   
10.
BackgroundThe Flex VP is a longitudinal micro-incision catheter approved for vessel prepping of femoropopliteal arteries and arteriovenous fistulas. In this study, we evaluated the presence of deep dissections (adventitia) using IVUS in patients undergoing Flex VP followed by angioplasty (PTA) versus PTA alone.Methods17 patients (20 limbs) with femoropopliteal artery (FP) disease were prospectively and consecutively included (10 limbs received PTA followed by 10 limbs that received FLEX VP microincision catheter treatment followed by adjunctive PTA). Dissections post PTA, FLEX VP and FLEX VP+ PTA were evaluated using intravascular ultrasound (iDissection classification) and angiographically (NHLBI classification) by core laboratory. The evaluated segment of the vessel was prespecified at 10 cm at the most severe lesion location. Statistical differences were analyzed between the 2 groups at each appropriate procedural point for dissections, minimal luminal diameter (MLD), minimal luminal area (MLA), and residual stenosis. Statistical significance was determined by a p-value <0.05.ResultsBaseline demographics and angiographic variables were similar between the PTA vs FLEX VP + PTA groups with the exception of more males (87.5 % vs 33.3 %, p = 0.0274) and longer treated length (median 300 mm vs 150 mm, p = 0.0240) in the FLEX VP + PTA group. Lesion length, chronic total occlusions, angiographic and IVUS evaluated segment length for dissections, calcium severity and final balloon pressures and inflation duration were all similar between the 2 groups. Angiographic dissections were similar between the 2 groups but the increase in severe dissections from index to post POBA on IVUS (involving the adventitia) were significantly more for PTA when compared to FLEX VP + PTA (0 to 12 and 0 to 1 respectively, p = 0.0353). Bailout stenting was statistically similar for PTA as compared to FLEX VP + PTA per core lab evaluation (50 % vs 20 %, p = 0.3498). Minimal luminal area (MLA) gain by IVUS was similar between the 2 groups following FLEX VP + PTA vs PTA (7.4 mm2 vs 6.5 mm2, p = 0.7250). No serious major adverse events occurred in either group.ConclusionVessel prepping with the FLEX VP + PTA vs PTA yielded lower rates of adventitial dissections as seen on IVUS. The long-term outcomes of these findings remain unclear.  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