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   103520篇
  免费   7806篇
  国内免费   379篇
耳鼻咽喉   1134篇
儿科学   2551篇
妇产科学   1673篇
基础医学   14694篇
口腔科学   2207篇
临床医学   10664篇
内科学   21877篇
皮肤病学   1828篇
神经病学   11084篇
特种医学   4224篇
外国民族医学   6篇
外科学   14718篇
综合类   1274篇
一般理论   77篇
预防医学   8034篇
眼科学   1730篇
药学   7037篇
中国医学   111篇
肿瘤学   6782篇
  2023年   582篇
  2022年   1096篇
  2021年   2152篇
  2020年   1338篇
  2019年   1984篇
  2018年   2444篇
  2017年   1809篇
  2016年   2153篇
  2015年   2494篇
  2014年   3294篇
  2013年   4358篇
  2012年   6742篇
  2011年   6782篇
  2010年   4001篇
  2009年   3652篇
  2008年   6001篇
  2007年   6532篇
  2006年   6060篇
  2005年   5997篇
  2004年   5587篇
  2003年   4994篇
  2002年   4943篇
  2001年   1876篇
  2000年   1787篇
  1999年   1671篇
  1998年   1232篇
  1997年   1007篇
  1996年   822篇
  1995年   828篇
  1994年   712篇
  1993年   650篇
  1992年   1153篇
  1991年   1069篇
  1990年   1015篇
  1989年   973篇
  1988年   867篇
  1987年   819篇
  1986年   839篇
  1985年   834篇
  1984年   674篇
  1983年   583篇
  1982年   557篇
  1981年   455篇
  1980年   403篇
  1979年   514篇
  1978年   407篇
  1977年   370篇
  1975年   330篇
  1974年   361篇
  1973年   346篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.

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   
2.
3.
4.
International Journal of Clinical Oncology - Immune-checkpoint inhibitors (ICIs) are standard treatments for metastatic non-small cell lung cancer (NSCLC). Patients with poor performance status...  相似文献   
5.
6.
The current study explored the influence of three methods of parental emotion discourse (structured story-telling, reminiscing, and picture book) and their relation to preschoolers’ emotion understanding. Thirty-seven families participated in the study. Analyses showed that the structured story-telling method produced more emotion words, was high in unique emotion words, and was high for both emotion labelling and explanations. All three methods showed some potential to predict preschooler’s emotion understanding. Structured story-telling was best at predicting role-taking, while reminiscing and the picture book both were better at predicting situation knowledge. Additional studies are needed to further explore the influence of different methods of assessing emotion discourse to enhance validity and reliability of research in this field.  相似文献   
7.
8.
9.
10.
Nidogen 1 (NID1) is a glycoprotein found in basement membranes involved in cross-linking collagen IV and laminin. The role of NID in breast cancer has only been evaluated in a small number of studies and the findings of these studies have been inconsistent. Our previous work revealed that highly tumorigenic murine mammary tumor cells express high levels of Nid1 while weakly tumorigenic mammary tumor cells express low levels of Nid1. To investigate Nid1, two stable knockdown lines were created, and Nid1 knockdown was confirmed at both the mRNA and protein level. Nid1 knockdown significantly reduced cell proliferation and migration/invasion and these reductions in proliferation and migration/invasion could be rescued by conditioned media containing NID1 protein. The reduced migration/invasion observed in the Nid1 knockdown cells was not associated with significant alterations in the epithelial gene Cdh1 or the mesenchymal genes Snai1, Snai2, Twist1, Twist2, Zeb1 and Zeb2. Therefore, suppression of Nid1 expression reduces proliferation and migration/invasion in claudin-low murine mammary tumor cells.  相似文献   
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