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   1145844篇
  免费   82660篇
  国内免费   2905篇
耳鼻咽喉   15228篇
儿科学   39189篇
妇产科学   32097篇
基础医学   167326篇
口腔科学   33423篇
临床医学   102870篇
内科学   221722篇
皮肤病学   27271篇
神经病学   93959篇
特种医学   43840篇
外国民族医学   305篇
外科学   169028篇
综合类   24347篇
一般理论   441篇
预防医学   87989篇
眼科学   25592篇
药学   82341篇
  3篇
中国医学   2384篇
肿瘤学   62054篇
  2021年   9631篇
  2019年   9891篇
  2018年   14723篇
  2017年   11438篇
  2016年   13211篇
  2015年   14257篇
  2014年   18756篇
  2013年   28843篇
  2012年   38200篇
  2011年   41064篇
  2010年   23961篇
  2009年   21418篇
  2008年   37967篇
  2007年   39916篇
  2006年   39815篇
  2005年   38098篇
  2004年   36759篇
  2003年   35414篇
  2002年   34128篇
  2001年   50738篇
  2000年   52816篇
  1999年   42979篇
  1998年   12444篇
  1997年   11145篇
  1996年   10992篇
  1995年   10437篇
  1994年   9725篇
  1993年   9070篇
  1992年   32814篇
  1991年   31948篇
  1990年   31477篇
  1989年   30349篇
  1988年   27567篇
  1987年   27780篇
  1986年   25803篇
  1985年   25146篇
  1984年   18917篇
  1983年   15969篇
  1982年   9791篇
  1979年   17238篇
  1978年   12578篇
  1977年   10720篇
  1976年   10110篇
  1975年   10528篇
  1974年   12645篇
  1973年   12121篇
  1972年   11105篇
  1971年   10359篇
  1970年   9596篇
  1969年   8915篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
95.
Gastroesophageal reflux is the most common benign disorder of the esophagus and laparoscopic Nissen fundoplication has become the standard surgical treatment for its treatment. In our area, where the use of bougie calibration is debatable, postoperative dysphagia is encountered often after this surgery although it is usually not permanent. The aim of this study was to investigate the effect of using a soft silicone tube 39 F in diameter for esophageal calibration during laparoscopic Nissen fundoplication on the incidence of postoperative dysphagia. We divided cases scheduled to undergo laparoscopic Nissen fundoplication between January 2009 and November 2010 into two groups, each consisting 25 patients. Esophageal calibration with a 39 F silicone orogastric tube was used for the first group while there was no operative calibration in the second group. The surgical duration was recorded; the presence and severity of the postoperative dysphagia was calculated by using a dysphagia severity scoring system during the 1-year postoperative follow-up. The dysphagia severity scores were significantly lower in group 1 than group 2 on the postoperative second day and at the end of the first week and first month. We did not find a significant difference at the end of the 6-month and first year. There was also no significant difference regarding surgery duration. The use of a soft orogastric tube 39 F in diameter for esophagus calibration during laparoscopic Nissen fundoplication has significantly decreased the incidence of postoperative transient dysphagia without affecting the duration of surgery. Although dysphagia gradually resolves in the majority of patients, a safe and easy calibration method for its prevention is worth developing, and we believe that the use of our method in larger series could be beneficial.  相似文献   
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.
98.
99.
100.
Introduction: Tamoxifen dominates the anti-estrogenic therapy in the early and metastatic breast cancer setting. Tamoxifen has a complex metabolism, being mainly metabolized by CYP2D6 into its 30–100 times more potent metabolite, endoxifen. Recently, a phase I study in which endoxifen as an orally z-endoxifen hydrochloride has been successfully evaluated.

Areas covered: the principal pharmacogenetic and non-genetic differences in the pharmacology of tamoxifen and endoxifen are evaluated. To this end, references from PubMed, Embase or Web of Science, among others, were reviewed As non-genetic factors, important differences and similarities such age, or adherence to tamoxifen therapy are comprehensively illustrated. Additionally, since CYP2D6 genotypes are considered the main limitation of tamoxifen, many studies have investigated the association between the worsened clinical outcomes in patients with non-functional CYP2D6 genotypes. In this review, an overview of the research on this field is presented. Also, a summary describing the literature about individualizing tamoxifen therapy with endoxifen concentrations and its limitations is listed.

Expert opinion: z-endoxifen hydrochloride is only investigated in the metastatic setting, still more research is required before its place in therapeutics is known. Similarly, monitoring tamoxifen efficacy based on endoxifen concentrations might not be overall recommended due to the limited evidence available.  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