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   32311篇
  免费   2003篇
  国内免费   100篇
耳鼻咽喉   253篇
儿科学   1119篇
妇产科学   984篇
基础医学   3639篇
口腔科学   411篇
临床医学   5911篇
内科学   5365篇
皮肤病学   347篇
神经病学   3122篇
特种医学   678篇
外国民族医学   1篇
外科学   3124篇
综合类   304篇
现状与发展   1篇
一般理论   50篇
预防医学   4431篇
眼科学   457篇
药学   1897篇
中国医学   33篇
肿瘤学   2287篇
  2023年   191篇
  2022年   128篇
  2021年   560篇
  2020年   435篇
  2019年   673篇
  2018年   817篇
  2017年   574篇
  2016年   648篇
  2015年   687篇
  2014年   1015篇
  2013年   1627篇
  2012年   2351篇
  2011年   2481篇
  2010年   1309篇
  2009年   1147篇
  2008年   2235篇
  2007年   2448篇
  2006年   2304篇
  2005年   2275篇
  2004年   2083篇
  2003年   1998篇
  2002年   1904篇
  2001年   261篇
  2000年   227篇
  1999年   316篇
  1998年   331篇
  1997年   262篇
  1996年   191篇
  1995年   264篇
  1994年   215篇
  1993年   217篇
  1992年   153篇
  1991年   161篇
  1990年   155篇
  1989年   122篇
  1988年   118篇
  1987年   109篇
  1986年   103篇
  1985年   110篇
  1984年   140篇
  1983年   149篇
  1982年   152篇
  1981年   148篇
  1980年   123篇
  1979年   66篇
  1978年   82篇
  1977年   58篇
  1976年   55篇
  1975年   42篇
  1974年   42篇
排序方式: 共有10000条查询结果,搜索用时 183 毫秒
1.
2.
Delirium is one of the most commonly occurring postoperative complications in older adults. It occurs due to the vulnerability of cerebral functioning to pathophysiological stressors. Identification of those at increased risk of developing delirium early in the surgical pathway provides an opportunity for modification of predisposing and precipitating risk factors and effective shared decision-making. No single delirium prediction tool is used widely in surgical settings. Multi-component interventions to prevent delirium involve structured risk factor modification supported by geriatrician input; these are clinically efficacious and cost effective. Barriers to the widespread implementation of such complex interventions exist, resulting in an ‘implementation gap’. There is a lack of evidence for pharmacological prophylaxis for the prevention of delirium. Current evidence suggests that avoidance of peri-operative benzodiazepines, careful titration of anaesthetic depth guided by processed electroencephalogram monitoring and treatment of pain are the most effective strategies to minimise the risk of delirium. Addressing postoperative delirium requires a collaborative, whole pathway approach, beginning with the early identification of those patients who are at risk. The research agenda should continue to examine the potential for pharmacological prophylaxis to prevent delirium while also addressing how successful models of delirium prevention can be translated from one setting to another, underpinned by implementation science methodology.  相似文献   
3.
Cheryl L. Rock PhD  RD  Cynthia A. Thomson PhD  RD  Kristen R. Sullivan MS  MPH  Carol L. Howe MD  MLS  Lawrence H. Kushi ScD  Bette J. Caan DrPH  Marian L. Neuhouser PhD  RD  Elisa V. Bandera MD  PhD  Ying Wang PhD  Kimberly Robien PhD  RD  Karen M. Basen-Engquist PhD  MPH  Justin C. Brown PhD  Kerry S. Courneya PhD  Tracy E. Crane PhD  RDN  David O. Garcia PhD  FACSM  Barbara L. Grant MS  RDN  CSO  FAND  Kathryn K. Hamilton MA  RDN  CSO  CDN  FAND  Sheri J. Hartman PhD  Stacey A. Kenfield ScD  Maria Elena Martinez PhD  Jeffrey A. Meyerhardt MD  MPH  Larissa Nekhlyudov MD  MPH  Linda Overholser MD  Alpa V. Patel PhD  Bernardine M. Pinto PhD  Mary E. Platek PhD  RD  CDN  Erika Rees-Punia PhD  MPH  Colleen K. Spees PhD  MEd  RD  LD  FAND  Susan M. Gapstur PhD  Marjorie L. McCullough ScD  RD 《CA: a cancer journal for clinicians》2022,72(3):230-262
The overall 5-year relative survival rate for all cancers combined is now 68%, and there are over 16.9 million survivors in the United States. Evidence from laboratory and observational studies suggests that factors such as diet, physical activity, and obesity may affect risk for recurrence and overall survival after a cancer diagnosis. The purpose of this American Cancer Society guideline is to provide evidence-based, cancer-specific recommendations for anthropometric parameters, physical activity, diet, and alcohol intake for reducing recurrence and cancer-specific and overall mortality. The audiences for this guideline are health care providers caring for cancer survivors as well as cancer survivors and their families. The guideline is intended to serve as a resource for informing American Cancer Society programs, health policy, and the media. Sources of evidence that form the basis of this guideline are systematic literature reviews, meta-analyses, pooled analyses of cohort studies, and large randomized clinical trials published since 2012. Recommendations for nutrition and physical activity during cancer treatment, informed by current practice, large cancer care organizations, and reviews of other expert bodies, are also presented. To provide additional context for the guidelines, the authors also include information on the relationship between health-related behaviors and comorbidities, long-term sequelae and patient-reported outcomes, and health disparities, with attention to enabling survivors' ability to adhere to recommendations. Approaches to meet survivors' needs are addressed as well as clinical care coordination and resources for nutrition and physical activity counseling after a cancer diagnosis.  相似文献   
4.
Journal of Behavioral Medicine - Evidence supports the use of graphic warnings to educate the public about the health harms of smoking and suggests warnings eliciting negative emotional responses...  相似文献   
5.
Colorectal cancer (CRC) screening programs help diagnose cancer precursors and early cancers and help reduce CRC mortality. However, currently recommended tests, the fecal immunochemical test (FIT) and colonoscopy, have low uptake. There is therefore a pressing need for screening strategies that are minimally invasive and consequently more acceptable to patients, most likely blood based, to increase early CRC identification. MicroRNAs (miRNAs) released from cancer cells are detectable in plasma in a remarkably stable form, making them ideal cancer biomarkers. Using plasma samples from FIT-positive (FIT+) subjects in an Italian CRC screening program, we aimed to identify plasma circulating miRNAs that detect early CRC. miRNAs were initially investigated by quantitative real-time PCR in plasma from 60 FIT+ subjects undergoing colonoscopy at Fondazione IRCCS Istituto Nazionale dei Tumori, then tested on an internal validation cohort (IVC, 201 cases) and finally in a large multicenter prospective series (external validation cohort [EVC], 1121 cases). For each endoscopic lesion (low-grade adenoma [LgA], high-grade adenoma [HgA], cancer lesion [CL]), specific signatures were identified in the IVC and confirmed on the EVC. A two-miRNA-based signature for CL and six-miRNA signatures for LgA and HgA were selected. In a multivariate analysis including sex and age at blood collection, the areas under the receiver operating characteristic curve (95% confidence interval) of the signatures were 0.644 (0.607–0.682), 0.670 (0.626–0.714) and 0.682 (0.580–0.785) for LgA, HgA and CL, respectively. A miRNA-based test could be introduced into the FIT+ workflow of CRC screening programs so as to schedule colonoscopies only for subjects likely to benefit most.  相似文献   
6.
Background: The practice of Norwegian occupational therapists (OTs) in municipal practice is a little explored area and with the Coordination Reform Act from 2012, Norwegian OTs in municipal practice have received responsibilities concerning clients with cognitive impairments. The aim of this study was to explore municipal OTs experiences with assessment of clients with cognitive impairments.

Method: Fourteen individual interviews with OTs who worked with clients with cognitive impairments, were conducted. An inductive thematic analysis, using text condensation and coding, was performed.

Results: The results revealed three themes; power of occupation, advantages and disadvantages of assessments used and the need for competencies within municipal services. The participants emphasized using observation in the assessment process and reflected on pros and cons of the standardized assessment tools they used. They expressed a need for competence development, although it was difficult to prioritize to do so.

Conclusion: This study illustrated a conflicted practice related to choices OTs make in their practices. They valued the importance of working occupation based, however, they chose to use impairment based standardized assessments. They expressed a need to engage in professional development, but due to heavy workloads, the limited power they experienced and lack of knowledge, this was difficult.  相似文献   

7.
Patients with melanoma brain metastases (MBM) still have a very poor prognosis. Several treatment modalities have been investigated in an attempt to improve the management of MBM. This review aimed to evaluate the impact of current treatments for MBM on patient- and tumor-related outcomes, and to provide treatment recommendations for this patient population. A literature search in the databases PubMed, Embase, Web of Science and Cochrane was conducted up to January 8, 2019. Original articles published since 2010 describing patient- and tumor-related outcomes of adult MBM patients treated with clearly defined systemic therapy were included. Information on basic trial demographics, treatment under investigation and outcomes (overall and progression-free survival, local and distant control and toxicity) were extracted. We identified 96 eligible articles, comprising 95 studies. A large variety of treatment options for MBM were investigated, either used alone or as combined modality therapy. Combined modality therapy was investigated in 71% of the studies and resulted in increased survival and better distant/local control than monotherapy, especially with targeted therapy or immunotherapy. However, neurotoxic side-effects also occurred more frequently. Timing appeared to be an important determinant, with the best results when radiotherapy was given before or during systemic therapy. Improved tumor control and prolonged survival can be achieved by combining radiotherapy with immunotherapy or targeted therapy. However, more randomized controlled trials or prospective studies are warranted to generate proper evidence that can be used to change the standard of care for patients with MBM.  相似文献   
8.
Objectives: Black Caribbeans in the United States have been the victims of major discrimination (e.g. unfairly fired, denied a promotion, denied housing). What is not known is the degree to which they also experience more routine forms of everyday discrimination such as receiving poor restaurant service, being perceived as dishonest, and being followed in stores. This paper investigates the distribution and correlates of everyday discrimination among a national sample of black Caribbeans in the U.S.

Design: This analysis used the black Caribbean sub-sample (n?=?1,621) of the National Survey of American Life. Demographic and immigration status correlates of ten items from the Everyday Discrimination Scale were investigated: being treated with less courtesy, treated with less respect, receiving poor restaurant service, being perceived as not smart, being perceived as dishonest, being perceived as not as good as others, and being feared, insulted, harassed, or followed in stores.

Results: Roughly one out of ten black Caribbeans reported that, on a weekly basis, they were treated with less courtesy and other people acted as if they were better than them, were afraid of them, and as if they were not as smart. Everyday discrimination was more frequent for black Caribbeans who were male, never married, divorced/separated, earned higher incomes, and who were second or third generation immigrants. Black Caribbeans attributed the majority of the discrimination they experienced to their race.

Conclusion: To our knowledge, this is the first study to provide an in-depth investigation of everyday discrimination among the black Caribbean population. It provides the frequency, types and correlates of everyday discrimination reported by black Caribbeans in the United States. Understanding the frequency and types of discrimination is important because of the documented negative impacts of everyday discrimination on physical and mental health.  相似文献   

9.
10.
Background: There are evidence-practice gaps in all areas of aphasia management across the continuum of care. Despite the recognition that effective implementation strategies are needed to improve the consistency of speech pathologists’ aphasia management practices, there have been few studies investigating this important issue. Therefore, little is known about the effectiveness of implementation strategies in the field of aphasiology. In light of the developing field of knowledge translation, it is important to review the aphasia implementation literature to highlight current trends, draw together findings, and determine future implementation research needs.

Aims: To critically review, summarise, and discuss the implementation literature in the field of aphasiology to date, in order to guide clinical aphasiologists to work towards closing the evidence-practice gaps in aphasia management.

Main contribution: A review of the literature in this developing area of expertise in the field of aphasiology, with examples of practical applications.

Conclusions: Only six implementation studies have been published in aphasia (related to conversation partner training, discourse analysis, information provision, and collaborative goal-setting practices), showing there is a need for capacity building in this area. Therefore, we are not yet able to state what interventions are effective in which context, nor fully understand how behaviour change occurs for clinicians providing aphasia management. Implications for speech-language pathologists are discussed. An overarching call to action is the need for clinicians and researchers to work together to drive future implementation efforts that can succeed in closing the aphasia management evidence-practice gaps.  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