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   1406629篇
  免费   99659篇
  国内免费   2269篇
耳鼻咽喉   20407篇
儿科学   46585篇
妇产科学   41010篇
基础医学   206199篇
口腔科学   38952篇
临床医学   118187篇
内科学   274824篇
皮肤病学   29847篇
神经病学   111819篇
特种医学   57298篇
外国民族医学   390篇
外科学   219283篇
综合类   27352篇
现状与发展   1篇
一般理论   335篇
预防医学   99041篇
眼科学   32349篇
药学   106864篇
  2篇
中国医学   2767篇
肿瘤学   75045篇
  2018年   14176篇
  2016年   12697篇
  2015年   14554篇
  2014年   19119篇
  2013年   28636篇
  2012年   40247篇
  2011年   42184篇
  2010年   24992篇
  2009年   23131篇
  2008年   41145篇
  2007年   44662篇
  2006年   45288篇
  2005年   44761篇
  2004年   42864篇
  2003年   41881篇
  2002年   41257篇
  2001年   62337篇
  2000年   63826篇
  1999年   54317篇
  1998年   15400篇
  1997年   13794篇
  1996年   13803篇
  1995年   12948篇
  1994年   12334篇
  1993年   11393篇
  1992年   42629篇
  1991年   41982篇
  1990年   41504篇
  1989年   40187篇
  1988年   37356篇
  1987年   36621篇
  1986年   34900篇
  1985年   33306篇
  1984年   24845篇
  1983年   21522篇
  1982年   12882篇
  1981年   11394篇
  1979年   23600篇
  1978年   16592篇
  1977年   14359篇
  1976年   13514篇
  1975年   14992篇
  1974年   17511篇
  1973年   16817篇
  1972年   16069篇
  1971年   14937篇
  1970年   13835篇
  1969年   13322篇
  1968年   12558篇
  1967年   11013篇
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
1.
2.
Intratumor heterogeneity is a main cause of the dismal prognosis of glioblastoma (GBM). Yet, there remains a lack of a uniform assessment of the degree of heterogeneity. With a multiscale approach, we addressed the hypothesis that intratumor heterogeneity exists on different levels comprising traditional regional analyses, but also innovative methods including computer-assisted analysis of tumor morphology combined with epigenomic data. With this aim, 157 biopsies of 37 patients with therapy-naive IDH-wildtype GBM were analyzed regarding the intratumor variance of protein expression of glial marker GFAP, microglia marker Iba1 and proliferation marker Mib1. Hematoxylin and eosin stained slides were evaluated for tumor vascularization. For the estimation of pixel intensity and nuclear profiling, automated analysis was used. Additionally, DNA methylation profiling was conducted separately for the single biopsies. Scoring systems were established to integrate several parameters into one score for the four examined modalities of heterogeneity (regional, cellular, pixel-level and epigenomic). As a result, we could show that heterogeneity was detected in all four modalities. Furthermore, for the regional, cellular and epigenomic level, we confirmed the results of earlier studies stating that a higher degree of heterogeneity is associated with poorer overall survival. To integrate all modalities into one score, we designed a predictor of longer survival, which showed a highly significant separation regarding the OS. In conclusion, multiscale intratumor heterogeneity exists in glioblastoma and its degree has an impact on overall survival. In future studies, the implementation of a broadly feasible heterogeneity index should be considered.  相似文献   
3.
4.
5.
6.
Klawitter  Felix  Walter  Uwe  Axer  Hubertus  Ehler  Johannes 《Der Anaesthesist》2023,72(8):543-554
Die Anaesthesiologie - Die Intensive Care Unit-Acquired Weakness (ICUAW) stellt eine der häufigsten neuromuskulären Komplikationen in der Intensivmedizin dar. Besonders bei...  相似文献   
7.
Vaccination is a vital health care initiative to prevent individual and population infection. To increase vaccination rates the federal government implemented the ‘No Jab, No Pay’ policy, where eligibility for several government benefits required children to be fully vaccinated by removing ‘conscientious objections’ and expanding the age range of children whose families receive benefits. This study assesses the impact of this policy at a local area within a single medical practice community in NSW, Australia. A retrospective clinical audit was performed between 2012 and 2017 on a single general practice's vaccination records for children ≤19 years. Catch-up vaccinations were assessed based on age at vaccination. Incidence of catch-up vaccinations was assessed for each of four years before and two years after the implementation of the ‘No Jab, No Pay’ policy in January 2016, along with the age of children and vaccination(s) given. Catch-up vaccinations were assessed temporally either side of implementation of ‘No Jab, No Pay’. Comparing the average annual vaccination catch-up incidence rate of 6.2% pre-implementation (2012–2015), there was an increase to 9.2% in 2016 (p < .001) and 7.8% in 2017 (p = .027). Secondary outcome measurement of catch-up vaccination incidence rates before (2012–2015) and after (2016–2017) ‘No Jab, No Pay’ implementation showed statistically significant increases for children aged 8–11 years (3.2%–5.6%, p = .038), 12–15 years (7.5%–14.7%, p < .001) and 16–19 years (3.3%–10.2%, p < .001) along with a statistically significant reduction in children aged 1–3 years (11.4%–6.2%, p = .015). Also, catch-up rates for DTPa significantly increased after program implementation. This study demonstrates that the Australian federal government vaccination policy ‘No Jab, No Pay’ was coincident with an increase in catch-up vaccinations within a rural NSW community served by one medical practice, especially for older children.  相似文献   
8.
ABSTRACT

Objective: Dry eye is reported to be associated with several neurological diseases. The aim of this study is to evaluate the patients with hemiplegia after stroke for dry eye and compare their results with a control group.

Materials and methods: Forty-five patients with hemiplegia and 45 individuals as the control group were included in the study. Tear function tests (Schirmer and tear breakup time) and a dry eye questionnaire for dry eye symptoms (ocular surface disease index) were performed and the results of the two groups were compared.

Results: Schirmer test results were significantly lower in the post-stroke hemiplegia group compared to the control group (11.3 ± 8.2 mm and 20.6 ± 11.6 mm, respectively, p < .001). Tear breakup time results were significantly lower in the post-stroke hemiplegia group compared to the control group (7.9 ± 3.1 s and 12.1 ± 4.3 s, respectively, p < .001). Ocular surface disease index scores were not significantly different between hemiplegia and control groups (21.6 ± 20.0 and 19.8 ± 13.9, respectively, p = .635). Schirmer scores lower than 10 mm (60% and 30%, p < .001) and tear breakup time results lower than 10 s (65.6% and 28.9%, p < .001) were also higher in the hemiplegia group compared to control group.

Conclusion: We found lower Schirmer test and tear breakup time results and similar OSDI scores in hemiplegia patients compared to controls. Hemiplegia patients may have dry eye without typical symptoms. This should be taken into consideration in the follow-up and rehabilitation of post-stroke hemiplegia patients.  相似文献   
9.
10.
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