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   4072619篇
  免费   301698篇
  国内免费   10216篇
耳鼻咽喉   57474篇
儿科学   130377篇
妇产科学   111149篇
基础医学   568524篇
口腔科学   116952篇
临床医学   375237篇
内科学   789443篇
皮肤病学   91245篇
神经病学   338065篇
特种医学   158570篇
外国民族医学   1438篇
外科学   610099篇
综合类   91173篇
现状与发展   6篇
一般理论   1720篇
预防医学   325291篇
眼科学   94697篇
药学   301322篇
  11篇
中国医学   7985篇
肿瘤学   213755篇
  2018年   43677篇
  2017年   33604篇
  2016年   38166篇
  2015年   43087篇
  2014年   60664篇
  2013年   92087篇
  2012年   122375篇
  2011年   129878篇
  2010年   77861篇
  2009年   74443篇
  2008年   121866篇
  2007年   129441篇
  2006年   131190篇
  2005年   126840篇
  2004年   122233篇
  2003年   117844篇
  2002年   114678篇
  2001年   187054篇
  2000年   192545篇
  1999年   163313篇
  1998年   48488篇
  1997年   43272篇
  1996年   42905篇
  1995年   41618篇
  1994年   38636篇
  1993年   36152篇
  1992年   129759篇
  1991年   125534篇
  1990年   121343篇
  1989年   117251篇
  1988年   108369篇
  1987年   106749篇
  1986年   100832篇
  1985年   96582篇
  1984年   72640篇
  1983年   62036篇
  1982年   37356篇
  1981年   33617篇
  1979年   66751篇
  1978年   47236篇
  1977年   40025篇
  1976年   37495篇
  1975年   39595篇
  1974年   47991篇
  1973年   45813篇
  1972年   43107篇
  1971年   39928篇
  1970年   37308篇
  1969年   35276篇
  1968年   32455篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
33.
34.
35.

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   
36.
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   

37.
Introduction: Allergic rhinitis is a common condition with increasing prevalence and is associated with several comorbid disorders such as bronchial asthma and atopic dermatitis. If allergen avoidance is not possible, allergen-specific immunotherapy is the only causal treatment option.

Areas covered: This review focuses on current treatments and the future outlook for allergic rhinitis. Pharmacotherapy includes mast cell stabilizers, antihistamines, glucocorticosteroids (GCSs), leukotriene receptor antagonists, and nasal decongestants. Nasal GCSs are currently regarded as the most effective treatment and are considered first-line therapy together with non-sedating antihistamines. The new formulation MP29-02 combines the nasal GCS fluticasone propionate with azelastine in one single spray and has achieved greater improvements than those under monotherapy with modern GCSs or antihistamines. Furthermore, this review discusses allergen immunotherapy alone and in combination with modern monoclonal antibodies.

Expert opinion: Despite the variety of medications for allergic rhinitis, ranging from general symptomatic agents like GCSs or decongestants, to more specific ones like histamine receptor or leukotriene blockers, to causal therapy like immunotherapy, many patients still experience treatment failures or unsatisfactory results. The ultimate goal may be to endotype every downstream pathway separately in order to offer patients individualized, targeted therapy with specific antibodies against the respective pathway.  相似文献   

38.
39.
40.
ABSTRACT

Forest workers, including loggers, foresters, and wildland firefighters, are regularly exposed to some of the most fatal occupational environments in the United States. These hazardous work environments may become even more complex and dynamic when subject to bark beetle outbreaks that have resulted in significant tree mortality. The impacts of tree death from bark beetles are significant, with the cumulative 17-year (2000–2016) footprint for bark beetle caused tree mortality estimated at 54 million acres. However, how workers think about and act in these environments is understudied. This study, therefore, approaches the issue of beetle kill and forest worker safety by examining the perspectives or workers themselves. Its contribution is to leverage ethnographic research to provide insights that can generate new research questions, better inform outreach, and ultimately improve worker safety outcomes. The resulting insights show that beetle kill was understood by workers as a hazard that increased the complexity and dynamism of the work environment, making situational awareness both more necessary and more difficult to maintain. While much research about situational awareness focuses on hazardous situations, it is suggested that building adequate situational awareness should also include broader considerations of organizational communication, as well as training and experience considered over the course of entire careers.  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