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   2801084篇
  免费   202803篇
  国内免费   8464篇
耳鼻咽喉   36831篇
儿科学   91192篇
妇产科学   77921篇
基础医学   392443篇
口腔科学   77788篇
临床医学   262477篇
内科学   560033篇
皮肤病学   67805篇
神经病学   232569篇
特种医学   105010篇
外国民族医学   739篇
外科学   408119篇
综合类   51390篇
现状与发展   5篇
一般理论   1031篇
预防医学   220239篇
眼科学   61378篇
药学   203077篇
  8篇
中国医学   6122篇
肿瘤学   156174篇
  2021年   25618篇
  2019年   25795篇
  2018年   36886篇
  2017年   28298篇
  2016年   32280篇
  2015年   36067篇
  2014年   48534篇
  2013年   71106篇
  2012年   95416篇
  2011年   100811篇
  2010年   60117篇
  2009年   56774篇
  2008年   92000篇
  2007年   97022篇
  2006年   97888篇
  2005年   93348篇
  2004年   89362篇
  2003年   85720篇
  2002年   82221篇
  2001年   131473篇
  2000年   134257篇
  1999年   113268篇
  1998年   32826篇
  1997年   29321篇
  1996年   29498篇
  1995年   28480篇
  1994年   25966篇
  1993年   24155篇
  1992年   86808篇
  1991年   83062篇
  1990年   80312篇
  1989年   77328篇
  1988年   70707篇
  1987年   69156篇
  1986年   64738篇
  1985年   61624篇
  1984年   45837篇
  1983年   38716篇
  1982年   22995篇
  1981年   20459篇
  1979年   39910篇
  1978年   28126篇
  1977年   23950篇
  1976年   22134篇
  1975年   23485篇
  1974年   27680篇
  1973年   26303篇
  1972年   24676篇
  1971年   22771篇
  1970年   20951篇
排序方式: 共有10000条查询结果,搜索用时 796 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.
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.
Journal of Medical Ultrasonics - Chronic liver disease is still a major problem because disease progression will ultimately lead to liver cirrhosis. Portal hypertension is the hallmark in advanced...  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