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   3271024篇
  免费   232287篇
  国内免费   8464篇
耳鼻咽喉   45115篇
儿科学   108364篇
妇产科学   90494篇
基础医学   460634篇
口腔科学   89901篇
临床医学   298030篇
内科学   637255篇
皮肤病学   78156篇
神经病学   265582篇
特种医学   126465篇
外国民族医学   918篇
外科学   489253篇
综合类   65592篇
现状与发展   6篇
一般理论   1241篇
预防医学   247098篇
眼科学   73925篇
药学   244593篇
  13篇
中国医学   7105篇
肿瘤学   182035篇
  2021年   25235篇
  2019年   25941篇
  2018年   36569篇
  2017年   28237篇
  2016年   32620篇
  2015年   36629篇
  2014年   50317篇
  2013年   75165篇
  2012年   100494篇
  2011年   106238篇
  2010年   63898篇
  2009年   60904篇
  2008年   98978篇
  2007年   105332篇
  2006年   107136篇
  2005年   102732篇
  2004年   98572篇
  2003年   95118篇
  2002年   91849篇
  2001年   159540篇
  2000年   163524篇
  1999年   137685篇
  1998年   39086篇
  1997年   34681篇
  1996年   34844篇
  1995年   33656篇
  1994年   30652篇
  1993年   28756篇
  1992年   106474篇
  1991年   102523篇
  1990年   99686篇
  1989年   96423篇
  1988年   88076篇
  1987年   86064篇
  1986年   80958篇
  1985年   77041篇
  1984年   57199篇
  1983年   48204篇
  1982年   28383篇
  1979年   50611篇
  1978年   35320篇
  1977年   30636篇
  1976年   27807篇
  1975年   30147篇
  1974年   35399篇
  1973年   33772篇
  1972年   31889篇
  1971年   29659篇
  1970年   27255篇
  1969年   26247篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
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   
3.
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   
4.

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   
5.
6.
7.
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   
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