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   3718318篇
  免费   311635篇
  国内免费   13769篇
耳鼻咽喉   51059篇
儿科学   118718篇
妇产科学   97487篇
基础医学   582099篇
口腔科学   102953篇
临床医学   332611篇
内科学   663049篇
皮肤病学   95295篇
神经病学   317663篇
特种医学   148978篇
外国民族医学   498篇
外科学   573290篇
综合类   113996篇
现状与发展   23篇
一般理论   2393篇
预防医学   310505篇
眼科学   85907篇
药学   260438篇
  22篇
中国医学   10128篇
肿瘤学   176610篇
  2021年   55135篇
  2020年   35115篇
  2019年   58055篇
  2018年   71487篇
  2017年   54517篇
  2016年   60312篇
  2015年   74312篇
  2014年   108600篇
  2013年   173731篇
  2012年   97707篇
  2011年   98191篇
  2010年   117927篇
  2009年   122182篇
  2008年   85891篇
  2007年   89207篇
  2006年   100145篇
  2005年   95295篇
  2004年   97846篇
  2003年   88264篇
  2002年   78114篇
  2001年   121169篇
  2000年   115482篇
  1999年   111968篇
  1998年   67112篇
  1997年   64644篇
  1996年   62650篇
  1995年   58261篇
  1994年   52396篇
  1993年   48945篇
  1992年   83178篇
  1991年   79666篇
  1990年   76180篇
  1989年   74809篇
  1988年   69640篇
  1987年   68353篇
  1986年   65148篇
  1985年   64985篇
  1984年   56729篇
  1983年   51403篇
  1982年   44802篇
  1981年   41961篇
  1980年   39558篇
  1979年   49104篇
  1978年   41053篇
  1977年   36858篇
  1976年   34142篇
  1975年   32918篇
  1974年   35629篇
  1973年   34293篇
  1972年   31782篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
65.
66.
67.

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   
68.
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   

69.
70.

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   
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