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   3312612篇
  免费   269020篇
  国内免费   13500篇
耳鼻咽喉   44922篇
儿科学   102612篇
妇产科学   83963篇
基础医学   529660篇
口腔科学   89200篇
临床医学   297584篇
内科学   576809篇
皮肤病学   90516篇
神经病学   281094篇
特种医学   131191篇
外国民族医学   225篇
外科学   512577篇
综合类   100233篇
现状与发展   23篇
一般理论   2188篇
预防医学   273487篇
眼科学   75953篇
药学   232633篇
  27篇
中国医学   9967篇
肿瘤学   160268篇
  2021年   55025篇
  2020年   35056篇
  2019年   57922篇
  2018年   70837篇
  2017年   54009篇
  2016年   59718篇
  2015年   73966篇
  2014年   108190篇
  2013年   173307篇
  2012年   88167篇
  2011年   87371篇
  2010年   115611篇
  2009年   120375篇
  2008年   74270篇
  2007年   76738篇
  2006年   87825篇
  2005年   82848篇
  2004年   84663篇
  2003年   75748篇
  2002年   65442篇
  2001年   107059篇
  2000年   99896篇
  1999年   98825篇
  1998年   65005篇
  1997年   62828篇
  1996年   60594篇
  1995年   56156篇
  1994年   50045篇
  1993年   46802篇
  1992年   68010篇
  1991年   64356篇
  1990年   61410篇
  1989年   60528篇
  1988年   55519篇
  1987年   54006篇
  1986年   51205篇
  1985年   50929篇
  1984年   46664篇
  1983年   42686篇
  1982年   40779篇
  1981年   38379篇
  1980年   36316篇
  1979年   37668篇
  1978年   33360篇
  1977年   31342篇
  1976年   28143篇
  1975年   27036篇
  1974年   27209篇
  1973年   26176篇
  1972年   24572篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
Objective Consensus that enhanced teamwork is necessary for efficient and effective primary care delivery is growing. We sought to identify how electronic health records (EHRs) facilitate and pose challenges to primary care teams as well as how practices are overcoming these challenges.Methods Practices in this qualitative study were selected from those recognized as patient-centered medical homes via the National Committee for Quality Assurance 2011 tool, which included a section on practice teamwork. We interviewed 63 respondents, ranging from physicians to front-desk staff, from 27 primary care practices ranging in size, type, geography, and population size.Results EHRs were found to facilitate communication and task delegation in primary care teams through instant messaging, task management software, and the ability to create evidence-based templates for symptom-specific data collection from patients by medical assistants and nurses (which can offload work from physicians). Areas where respondents felt that electronic medical record EHR functionalities were weakest and posed challenges to teamwork included the lack of integrated care manager software and care plans in EHRs, poor practice registry functionality and interoperability, and inadequate ease of tracking patient data in the EHR over time.Discussion Practices developed solutions for some of the challenges they faced when attempting to use EHRs to support teamwork but wanted more permanent vendor and policy solutions for other challenges.Conclusions EHR vendors in the United States need to work alongside practicing primary care teams to create more clinically useful EHRs that support dynamic care plans, integrated care management software, more functional and interoperable practice registries, and greater ease of data tracking over time.  相似文献   
94.
95.
96.

Background

Nursing Home Compare (NHC) ratings, created and maintained by Medicare, are used by both hospitals and consumers to aid in the skilled nursing facility (SNF) selection process. To date, no studies have linked NHC ratings to actual episode-based outcomes. The purpose of this study was to evaluate whether NHC ratings are valid predictors of 90-day complications, readmission, and bundle costs for patients discharged to an SNF after primary total joint arthroplasty (TJA).

Methods

All SNF-discharged primary TJA cases in 2017 at a multihospital academic health system were queried. Demographic, psychosocial, and clinical variables were manually extracted from the health record. Medicare NHC ratings were then collected for each SNF. For patients in the Medicare bundle, postacute and total bundle cost was extracted from claims.

Results

Four hundred eighty-eight patients were discharged to a total of 105 unique SNFs. In multivariate analysis, overall NHC rating was not predictive of 90-day readmission/major complications, >75th percentile postacute cost, or 90-day bundle cost exceeding the target price. SNF health inspection and quality measure ratings were also not predictive of 90-day readmission/major complications or bundle performance. A higher SNF staffing rating was independently associated with a decreased odds for >75th percentile 90-day postacute spend (odds ratio, 0.58; P = .01) and a 90-day bundle cost exceeding the target price (odds ratio = 0.69; P = .02) but was similarly not predictive of 90-day readmission/complications.

Conclusion

Results of our study suggest that Medicare's NHC tool is not a useful predictor of 90-day costs, complications, or readmissions for SNFs within our health system.  相似文献   
97.
Purpose/aim: To focus on current aspects of primary thyroid lymphoma (PTL), which is a rare clinical entity usually manifested by a rapidly growing mass in the neck that can cause pressure symptoms.

Materials and Methods: Relevant papers in PubMed published through June 2017 were selected to track updated information about PTL with an emphasis on diagnosis and novel therapeutic management.

Results: The most frequent cases include non-Hodgkin lymphoma derived from B-cells, mainly diffuse large B-cell lymphoma (DLBCL) followed by mucosa-associated lymphoid tissue (MALT) lymphoma or a mixed type. Other subtypes are less common. Lymphomas derived from T-cells and Hodgkin lymphomas are extremely rare. Hashimoto's autoimmune thyroiditis has been implicated as a risk factor for lymphoma. At the molecular level, the Wnt5a protein and its receptor Ror2 are involved in the course of the disease. Ultrasonography, fine needle aspiration (FNA) biopsy, and core or open biopsy combined with new diagnostic facilities contribute to an accurate diagnosis. An increased potential exists for a cure without the need for a radical surgical procedure. Modern chemoradiation therapy plus the monoclonal antibody rituximab, which acts against CD20, have limited the need for surgical interventions and provide an excellent outcome in most cases. However, some cases have resulted in treatment failure or recurrence.

Conclusions: A multidisciplinary approach must be used to define the management policy in each case. Future efforts by researchers are likely to be focused on the molecular level.  相似文献   

98.
99.

Aims

Variations of the anatomy of donor hepatic arteries increase the number of arterial anastomoses during liver transplantation and, possibly, the incidence of hepatic artery thrombosis (HAT). In this study, we describe the arterial anatomic variations in liver grafts procured and transplanted by a single center in Greece, the techniques of arterial anastomosis, and their effect on the incidence of early HAT.

Materials and Methods

From January 2013 to December 2017, the arterial anatomy of 116 grafts procured for liver transplantation were recorded, as well as the technique of arterial anastomosis and the incidence of early hepatic artery thrombosis (HAT <30 days).

Results

A single hepatic artery was recorded in 72.41% of the procured grafts, an aberrant left hepatic artery (accessory or replaced) in 18 grafts (15.52%), and an aberrant right hepatic artery (accessory or replaced) in 17 grafts (14.66%), while other variations were observed in less than 1% of the procured livers. Of the 116 primary liver transplantations, 6 patients (5.17%) developed early HAT <30 days. Two of these patients (1.72%) had 1 anastomosis of the hepatic artery and 4 (3.45%) had 2 anastomoses due to anatomic variations.

Conclusions

Anatomic variations of the hepatic artery in liver grafts is a common finding and increase the incidence of early HAT but not to a degree to make these grafts unusable.  相似文献   
100.
Background & Aims: Impaired message-structure mapping results in deficits in both sentence production and comprehension in aphasia. Structural priming has been shown to facilitate syntactic production for persons with aphasia (PWA). However, it remains unknown if structural priming is also effective in sentence comprehension. We examined if PWA show preserved and lasting structural priming effects during interpretation of syntactically ambiguous sentences and if the priming effects occur independently of or in conjunction with lexical (verb) information.

Methods & Procedures: Eighteen PWA and 20 healthy older adults (HOA) completed a written sentence-picture matching task involving the interpretation of prepositional phrases (PP; the chef is poking the solider with an umbrella) that were ambiguous between high (verb modifier) and low attachment (object noun modifier). Only one interpretation was possible for prime sentences, while both interpretations were possible for target sentences. In Experiment 1, the target was presented immediately after the prime (0-lag). In Experiment 2, two filler items intervened between the prime and the target (2-lag). Within each experiment, the verb was repeated for half of the prime-target pairs, while different verbs were used for the other half. Participants’ off-line picture matching choices and response times were measured.

Results: After reading a prime sentence with a particular interpretation, HOA and PWA tended to interpret an ambiguous PP in a target sentence in the same way and with faster response times. Importantly, both groups continued to show this priming effect over a lag (Experiment 2), although the effect was not as reliable in response times. However, neither group showed lexical (verb-specific) boost on priming, deviating from robust lexical boost seen in the young adults of prior studies.

Conclusions: PWA demonstrate abstract (lexically-independent) structural priming in the absence of a lexically-specific boost. Abstract priming is preserved in aphasia, effectively facilitating not only immediate but also longer-lasting structure-message mapping during sentence comprehension.  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