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   3466372篇
  免费   248473篇
  国内免费   9014篇
耳鼻咽喉   48109篇
儿科学   114467篇
妇产科学   97120篇
基础医学   491309篇
口腔科学   97878篇
临床医学   309555篇
内科学   679110篇
皮肤病学   81636篇
神经病学   281479篇
特种医学   133165篇
外国民族医学   1048篇
外科学   520303篇
综合类   69926篇
现状与发展   6篇
一般理论   1205篇
预防医学   269382篇
眼科学   79454篇
药学   256362篇
  9篇
中国医学   7140篇
肿瘤学   185196篇
  2018年   39256篇
  2017年   29572篇
  2016年   33868篇
  2015年   38200篇
  2014年   52094篇
  2013年   78595篇
  2012年   106055篇
  2011年   112678篇
  2010年   67190篇
  2009年   63457篇
  2008年   105011篇
  2007年   112043篇
  2006年   113768篇
  2005年   109426篇
  2004年   105223篇
  2003年   101587篇
  2002年   98478篇
  2001年   159582篇
  2000年   163621篇
  1999年   138307篇
  1998年   40076篇
  1997年   35442篇
  1996年   35730篇
  1995年   34348篇
  1994年   31773篇
  1993年   29802篇
  1992年   108901篇
  1991年   105488篇
  1990年   102776篇
  1989年   99506篇
  1988年   91724篇
  1987年   90003篇
  1986年   84992篇
  1985年   81184篇
  1984年   60350篇
  1983年   51784篇
  1982年   30862篇
  1981年   27419篇
  1979年   54894篇
  1978年   38749篇
  1977年   33291篇
  1976年   31015篇
  1975年   33495篇
  1974年   39506篇
  1973年   37786篇
  1972年   35821篇
  1971年   33212篇
  1970年   30998篇
  1969年   29846篇
  1968年   27697篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Quality of Life Research - The COVID-19 pandemic might add to the stressors experienced by people living with rheumatic diseases. This study aimed to examine rheumatic patients’ functional...  相似文献   
2.
Molnár  B.  Aroca  S.  Dobos  A.  Orbán  K.  Szabó  J.  Windisch  P.  Stähli  A.  Sculean  A. 《Clinical oral investigations》2022,26(12):7135-7142
Clinical Oral Investigations - To evaluate t he long-term outcomes following treatment of RT 1 multiple adjacent gingival recessions (MAGR) using the modified coronally advanced tunnel (MCAT) with...  相似文献   
3.

Interstitial lung disease (ILD) represents a significant cause of morbidity and mortality in systemic sclerosis (SSc). The purpose of this study was to examine recirculating lymphocytes from SSc patients for potential biomarkers of interstitial lung disease (ILD). Peripheral blood mononuclear cells (PBMCs) were isolated from patients with SSc and healthy controls enrolled in the Vanderbilt University Myositis and Scleroderma Treatment Initiative Center cohort between 9/2017–6/2019. Clinical phenotyping was performed by chart abstraction. Immunophenotyping was performed using both mass cytometry and fluorescence cytometry combined with t-distributed stochastic neighbor embedding analysis and traditional biaxial gating. This study included 34 patients with SSc-ILD, 14 patients without SSc-ILD, and 25 healthy controls. CD21lo/neg cells are significantly increased in SSc-ILD but not in SSc without ILD (15.4 ± 13.3% vs. 5.8 ± 0.9%, p = 0.002) or healthy controls (5.0 ± 0.5%, p < 0.0001). While CD21lo/neg B cells can be identified from a single biaxial gate, tSNE analysis reveals that the biaxial gate is comprised of multiple distinct subsets, all of which are increased in SSc-ILD. CD21lo/neg cells in both healthy controls and SSc-ILD are predominantly tBET positive and do not have intracellular CD21. Immunohistochemistry staining demonstrated that CD21lo/neg B cells diffusely infiltrate the lung parenchyma of an SSc-ILD patient. Additional work is needed to validate this biomarker in larger cohorts and longitudinal studies and to understand the role of these cells in SSc-ILD.

  相似文献   
4.
5.
6.
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   
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