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   1934篇
  免费   129篇
  国内免费   4篇
耳鼻咽喉   15篇
儿科学   57篇
妇产科学   53篇
基础医学   217篇
口腔科学   39篇
临床医学   272篇
内科学   575篇
皮肤病学   17篇
神经病学   207篇
特种医学   23篇
外科学   151篇
综合类   13篇
一般理论   2篇
预防医学   191篇
眼科学   53篇
药学   104篇
中国医学   2篇
肿瘤学   76篇
  2023年   24篇
  2022年   25篇
  2021年   46篇
  2020年   38篇
  2019年   55篇
  2018年   65篇
  2017年   42篇
  2016年   42篇
  2015年   44篇
  2014年   55篇
  2013年   101篇
  2012年   151篇
  2011年   149篇
  2010年   68篇
  2009年   61篇
  2008年   118篇
  2007年   103篇
  2006年   88篇
  2005年   90篇
  2004年   94篇
  2003年   85篇
  2002年   82篇
  2001年   38篇
  2000年   25篇
  1999年   43篇
  1998年   26篇
  1997年   8篇
  1996年   15篇
  1995年   12篇
  1994年   14篇
  1993年   8篇
  1992年   21篇
  1991年   29篇
  1990年   17篇
  1989年   14篇
  1988年   20篇
  1987年   13篇
  1986年   12篇
  1985年   9篇
  1984年   13篇
  1983年   9篇
  1982年   7篇
  1981年   6篇
  1979年   6篇
  1978年   7篇
  1977年   6篇
  1976年   5篇
  1974年   11篇
  1973年   13篇
  1972年   11篇
排序方式: 共有2067条查询结果,搜索用时 78 毫秒
31.
32.

Background

Health-related quality of life (HRQoL) is frequently assessed in randomised clinical trials (RCTs) in the intensive care unit (ICU), but data are limited regarding the proportions of patients without responses or not surviving to HRQoL follow-up and the handling of this. We aimed to describe the extent and pattern of missing HRQoL data in intensive care trials and describe how these data and deaths were handled statistically.

Methods

We conducted a systematic review and meta-analysis following a published protocol. We searched PubMed, EMBASE, CINAHL and Cochrane Library for RCTs involving adult ICU patients reporting HRQoL as an outcome and excluded RCTs unobtainable in full text. We performed risk of bias assessment independently and in duplicate.

Results

We included 196 outcomes from 88 RCTs published in the years 2002–2022; the numbers of patients alive and eligible to respond HRQoL were reported in 76% of trials. At follow-up, median 27% (interquartile range 14%–39%) of patients had died, and median 20% (9%–38%) of survivors did not respond across outcomes. Analyses of 80% of outcomes were restricted to complete cases only. The handling of non-survivors in analyses were reported for 46% of outcomes, with 26% of all outcomes reported as including non-survivors (using the value zero or the worst possible score).

Conclusion

For HRQoL outcomes in ICU trials, we found that mortality at time of follow-up was high and non-response among survivors frequent. The reporting and statistical handling of these issues were insufficient, which may have biased results.  相似文献   
33.
The loss of autonomy associated with dementia affects the people with dementia themselves as well as their caregivers who are often left feeling powerless and incompetent in their caregiving role. Most of the programs developed to support caregivers focus on burden and do not consider the positive aspects of caregiving. Leisure represents a way to enhance the presence of positive aspects in the caring experience. Moreover, leisure might contribute to the maintenance of satisfactory relationships between the caregivers and the person with dementia. An adapted leisure education program was developed as a means of support to caregiver involvement. This study (n = 49) aims to evaluate the impact of this program on caregivers’ well-being, self-efficacy towards adapted leisure, and quality of the relationship with the care receiver. Mixed methods were used. Pretest-posttest with a follow-up design made up the quantitative part. In addition, open-end interviews (n = 10) were conducted. The quantitative results showed few impacts of the program on caregivers. However, the qualitative analysis revealed that the intervention had positive impacts for the caregivers, care receivers and other family members. This study introduces caregiver support in a new, positive perspective by focusing on the positive aspects of caregiving rather than the burden.  相似文献   
34.
35.
The calprotectin level in the cerebrospinal fluid (CSF) of 15 HIV positive patients with symptoms from the central nervous system (CNS) was measured. All 5 patients with opportunistic infections had levels above the reference range and all 10 patients with HIV associated encephalopathy had levels within the reference range. Thus, the calprotectin level in CSF can be of diagnostic value in differentiating between HIV associated encephalopathy and opportunistic infection in the HIV positive patient with symptoms from the CNS.  相似文献   
36.
The objectives of the study were to compare the association and responsiveness of the functional autonomy measurement system (SMAF) and functional independence measure (FIM) as outcome measures addressing functional independence in stroke patients involved in an intensive rehabilitation program and to compare their relationships with a social participation measure after rehabilitation period. One hundred and thirty-two people who had a stroke were evaluated with the SMAF and FIM during the rehabilitation period (T1: admission; T2: discharge; n=132) and twice after discharge (T3=2 weeks; n=118; T4=6 months later; n=102). At T3 and T4, a participation measure, the assessment of life habits (LIFE-H), was added. The main findings are: (1) the total scores on the SMAF and FIM are strongly correlated together (r=0.93 to 0.95; p<0.001); 2) the responsiveness of both functional independence scales is similar even though the SMAF total score is more responsive to change than the FIM total score (standardized response mean: 1.20 vs. 0.97; p<0.01); (3) the SMAF and FIM are related similarly to the daily activities domain of the participation scale; and finally (4) the social roles domain of the participation scale is less related to the SMAF and MIF than the daily activities domain; however, the SMAF score is more related to the social roles domain than the MIF. Our results support the need to use supplementary measures, such as participation measure, that cover not only physical function but also the other domains of participation, such as interpersonal relationships and leisure, that can be disrupted following a stroke.  相似文献   
37.
Monitoring airway inflammation by means of induced sputum cell counts seems to improve the management of asthma. We sought to assess whether such monitoring at the end of periods at and away from work combined with the monitoring of PEF could improve the diagnosis of occupational asthma. We enrolled subjects suspected of having occupational asthma. Serial monitoring of PEF was performed during 2 weeks at and away from work. At the end of each period, induced sputum was collected. Specific inhalation challenge was subsequently performed. PEF graphs were interpreted visually by five independent observers. Forty-nine subjects, including 23 with positive specific inhalation challenge, completed the study. The addition of sputum cell counts to the monitoring of PEF increased the specificity of this test, respectively, by 18 (range [r] 13.7-25.5) or 26.8% (r 24.8-30.4) depending if an increase of sputum eosinophils greater than 1 or 2% when at work was considered as significant. The sensitivity increased by 8.2% (r 4.1-13.4) or decreased by 12.3% (r 3.1-24.1) depending on the cutoff value in sputum eosinophils chosen (greater than 1 or 2%, respectively). The addition of sputum cell counts to PEF monitoring is useful to improve the diagnosis of occupational asthma.  相似文献   
38.
Our previous work demonstrated 2 quantitative trait loci (QTLs), C2QTL1 and C2QTL2, for blood pressure (BP) located on chromosome (Chr) 2 of Dahl salt-sensitive (DSS) rats. However, for a lack of markers, the 2 congenic strains delineating C2QTL1 and C2QTL2 could not be separated. The position of the C2QTL1 was only inferred by comparing 2 congenic strains, one having and another lacking a BP effect. Furthermore, it was not known how adjacent QTLs would interact with one another on Chr 2. In the current investigation, first, a critical chromosome marker was developed to separate 2 C2QTLs. Second, a congenic substrain was created to cover a chromosome fragment thought to harbor C2QTL1. Finally, a series of congenic strains was produced to systematically and comprehensively cover the entire Chr 2 segment containing C2QTL2 and other regions previously untested. Consequently, a total of 3 QTLs were discovered, with C2QTL3 located between C2QTL1 and C2QTL2. C2QTL1, C2QTL2, and C2QTL3 reside in chromosome segments of 5.7 centiMorgan (cM), 3.5 cM, and 1.5 cM, respectively. C2QTL1 interacted epistatically with either C2QTL2 or C2QTL3, whereas C2QTL2 and C2QTL3 showed additive effects to each other. These results suggest that BP QTLs closely linked in a segment interact epistatically and additively to one another on Chr 2.  相似文献   
39.
40.
Objective: To evaluate the impact of amniotic fluid “sludge” (AFS) on the risk of preterm delivery and to describe the effect of antibiotic treatment in that situation.

Methods: Case–control study including singleton pregnancies with or without AFS, between 15–32 weeks of gestation. Factors associated with preterm delivery before 32 weeks, 34 weeks and 37 weeks were evaluated with univariate and multivariate logistic regression. Since all women with AFS in this study were treated with antibiotics, a historical comparison was performed with similar patients with AFS found before 2007 and not treated with antibiotics.

Results: AFS was observed in 90/1220 patients (7.4%). AFS was associated with shorter cervical length, greater body mass index, cervical cerclage and preterm birth before 28 weeks. However, after adjustment, AFS did not remain associated with preterm delivery before 32 or 34 weeks. The historical comparison suggested that azithromycin could significantly reduce the risk of preterm delivery before 34 weeks (odds ratio: 0.2; 95% CI: 0.04–0.92).

Conclusions: AFS, treated with azithromycin, was associated with a higher risk of prematurity, but not independently after adjustment for cervical length and second trimester vaginal bleeding. Further studies need to evaluate the effect of antibiotics in pregnancies with AFS.  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