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   674382篇
  免费   40291篇
  国内免费   922篇
耳鼻咽喉   9827篇
儿科学   22779篇
妇产科学   17654篇
基础医学   107866篇
口腔科学   19080篇
临床医学   56367篇
内科学   122725篇
皮肤病学   16589篇
神经病学   51013篇
特种医学   26868篇
外国民族医学   87篇
外科学   103787篇
综合类   9508篇
一般理论   155篇
预防医学   46437篇
眼科学   16489篇
药学   51664篇
中国医学   1324篇
肿瘤学   35376篇
  2018年   7642篇
  2017年   5850篇
  2016年   7176篇
  2015年   7998篇
  2014年   9694篇
  2013年   14647篇
  2012年   20810篇
  2011年   21691篇
  2010年   12691篇
  2009年   11295篇
  2008年   21017篇
  2007年   22842篇
  2006年   23084篇
  2005年   22930篇
  2004年   22181篇
  2003年   21442篇
  2002年   21212篇
  2001年   29626篇
  2000年   30681篇
  1999年   25419篇
  1998年   6897篇
  1997年   5922篇
  1996年   5945篇
  1995年   5371篇
  1994年   5030篇
  1992年   17913篇
  1991年   18457篇
  1990年   18541篇
  1989年   17795篇
  1988年   16318篇
  1987年   16145篇
  1986年   15219篇
  1985年   14524篇
  1984年   10825篇
  1983年   9218篇
  1982年   5226篇
  1979年   10722篇
  1978年   7817篇
  1977年   6576篇
  1976年   6304篇
  1975年   7431篇
  1974年   8692篇
  1973年   8093篇
  1972年   7934篇
  1971年   7620篇
  1970年   7006篇
  1969年   6680篇
  1968年   6306篇
  1967年   5730篇
  1966年   4960篇
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
1.
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   
2.
3.
Maternal and Child Health Journal - Early life exposures can have an impact on a child’s developmental trajectory and children born late preterm (34–36 weeks gestational age)...  相似文献   
4.
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   
5.
6.
7.
8.
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