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   186702篇
  免费   35628篇
  国内免费   1527篇
耳鼻咽喉   3486篇
儿科学   4709篇
妇产科学   3591篇
基础医学   14274篇
口腔科学   7175篇
临床医学   34617篇
内科学   44167篇
皮肤病学   4673篇
神经病学   20593篇
特种医学   7239篇
外国民族医学   1篇
外科学   32823篇
综合类   894篇
现状与发展   40篇
一般理论   194篇
预防医学   19289篇
眼科学   3864篇
药学   6641篇
中国医学   144篇
肿瘤学   15443篇
  2024年   803篇
  2023年   5676篇
  2022年   2500篇
  2021年   5754篇
  2020年   6857篇
  2019年   4633篇
  2018年   9845篇
  2017年   9401篇
  2016年   10118篇
  2015年   10480篇
  2014年   13913篇
  2013年   16653篇
  2012年   10903篇
  2011年   10763篇
  2010年   10701篇
  2009年   12406篇
  2008年   9441篇
  2007年   8170篇
  2006年   9134篇
  2005年   7644篇
  2004年   6484篇
  2003年   5755篇
  2002年   5193篇
  2001年   2363篇
  2000年   1575篇
  1999年   2294篇
  1998年   2879篇
  1997年   2548篇
  1996年   2462篇
  1995年   2212篇
  1994年   1494篇
  1993年   1337篇
  1992年   1075篇
  1991年   936篇
  1990年   788篇
  1989年   788篇
  1988年   776篇
  1987年   630篇
  1986年   621篇
  1985年   568篇
  1984年   595篇
  1983年   598篇
  1982年   556篇
  1981年   529篇
  1980年   378篇
  1979年   210篇
  1978年   310篇
  1977年   294篇
  1976年   212篇
  1974年   199篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
<正>Photobiomodulation (PBM)-the irradiation of cells or tissues with low-intensity red to near-infrared light-is emerging as an effective means of enhancing cell and tissue resilience and repair. As reviewed elsewhere (Gordon et al., 2019), the intracellular effects of  相似文献   
132.
ObjectivesCocaine is the second most frequently used illicit drug worldwide (after cannabis), and cocaine use disorder (CUD)-related deaths increased globally by 80% from 1990 to 2013. There is yet to be a regulatory-approved treatment. Emerging preclinical evidence indicates that deep brain stimulation (DBS) of the nucleus accumbens may be a therapeutic option. Prior to expanding the costly investigation of DBS for treatment of CUD, it is important to ensure societal cost-effectiveness.AimsWe conducted a threshold and cost-effectiveness analysis to determine the success rate at which DBS would be equivalent to contingency management (CM), recently identified as the most efficacious therapy for treatments of CUDs.Materials and MethodsQuality of life, efficacy, and safety parameters for CM were obtained from previous literature. Costs were calculated from a societal perspective. Our model predicted the utility benefit based on quality-adjusted life-years (QALYs) and incremental-cost-effectiveness ratio resulting from two treatments on a one-, two-, and five-year timeline.ResultsOn a one-year timeline, DBS would need to impart a success rate (ie, cocaine free) of 70% for it to yield the same utility benefit (0.492 QALYs per year) as CM. At no success rate would DBS be more cost-effective (incremental-cost-effectiveness ratio <$50,000) than CM during the first year. Nevertheless, as DBS costs are front loaded, DBS would need to achieve success rates of 74% and 51% for its cost-effectiveness to exceed that of CM over a two- and five-year period, respectively.ConclusionsWe find DBS would not be cost-effective in the short term (one year) but may be cost-effective in longer timelines. Since DBS holds promise to potentially be a cost-effective treatment for CUDs, future randomized controlled trials should be performed to assess its efficacy.  相似文献   
133.
134.
135.
136.
137.
138.
139.
Objective: Acute graft-versus-host disease (aGVHD) is a common and life-threatening complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). The extent to which aGVHD increases inpatient costs associated with allo-HSCT has not been thoroughly evaluated. In this analysis, mortality, hospital length of stay (LOS) and costs associated with aGVHD during allo-HSCT admissions are evaluated.

Methods: This is a retrospective analysis of discharge records from the National Inpatient Sample database for patients receiving allo-HSCT between 1 January 2009 and 31 December 2013. Allo-HSCT discharges with an aGVHD diagnosis were included in the aGVHD group and those without any graft-versus-host disease (GVHD) diagnosis comprised the non-GVHD group. Mortality, LOS and costs were compared between the two groups, as well as within subgroups, including age (<18 vs. ≥18 years) and survival status (alive vs. deceased) at discharge.

Results: Overall, mortality (16.2% vs. 5.3%; p?<?.01), median hospital LOS (42.0 vs. 26.0 days; p?<?.01) and median total costs ($173,144 vs. $98,982; p?<?.01) were significantly increased in patients with aGVHD versus those without GVHD during hospitalizations for allo-HSCT, irrespective of age group. Patients with aGVHD who were <18 years of age had a lower mortality rate but greater hospital LOS and total costs versus patients aged ≥18 years. Patients who died during allo-HSCT hospitalization had longer LOS and incurred greater costs than those who survived in both the aGVHD and non-GVHD groups.

Conclusion: Occurrence of aGVHD during allo-HSCT admissions resulted in a tripling of the mortality rate and a near doubling of hospital LOS and total costs. In addition, death during allo-HSCT hospitalizations was associated with greater healthcare utilization and costs. Effectively mitigating aGVHD may improve survival and substantially reduce hospital LOS and costs for allo-HSCT.  相似文献   

140.
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