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   596913篇
  免费   70317篇
  国内免费   492篇
耳鼻咽喉   8107篇
儿科学   20948篇
妇产科学   13022篇
基础医学   106963篇
口腔科学   17143篇
临床医学   59980篇
内科学   116542篇
皮肤病学   18871篇
神经病学   46408篇
特种医学   21780篇
外国民族医学   53篇
外科学   90864篇
综合类   7611篇
现状与发展   2篇
一般理论   128篇
预防医学   42346篇
眼科学   13093篇
药学   46520篇
  1篇
中国医学   2114篇
肿瘤学   35226篇
  2021年   5072篇
  2020年   7235篇
  2019年   14343篇
  2018年   15182篇
  2017年   14950篇
  2016年   16332篇
  2015年   16658篇
  2014年   18269篇
  2013年   22056篇
  2012年   19248篇
  2011年   20978篇
  2010年   18371篇
  2009年   13797篇
  2008年   17493篇
  2007年   18109篇
  2006年   17646篇
  2005年   16764篇
  2004年   16398篇
  2003年   15802篇
  2002年   15429篇
  2001年   23148篇
  2000年   23606篇
  1999年   19143篇
  1998年   5247篇
  1997年   4372篇
  1996年   4408篇
  1992年   14421篇
  1991年   15819篇
  1990年   15950篇
  1989年   15628篇
  1988年   14308篇
  1987年   14198篇
  1986年   13168篇
  1985年   12686篇
  1984年   9394篇
  1983年   8000篇
  1982年   4178篇
  1979年   8937篇
  1978年   6383篇
  1977年   5149篇
  1976年   5504篇
  1975年   6613篇
  1974年   7419篇
  1973年   7158篇
  1972年   6597篇
  1971年   6309篇
  1970年   5887篇
  1969年   5467篇
  1968年   5161篇
  1967年   4621篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
1.
Journal of Behavioral Medicine - Evidence supports the use of graphic warnings to educate the public about the health harms of smoking and suggests warnings eliciting negative emotional responses...  相似文献   
2.
ObjectiveSpinal cord stimulation (SCS) is an effective treatment in failed back surgery syndrome (FBSS). We studied the effect of preimplantation opioid use on SCS outcome and the effect of SCS on opioid use during a two-year follow-up period.Materials and methodsThe study cohort included 211 consecutive FBSS patients who underwent an SCS trial from January 1997 to March 2014. Participants were divided into groups, which were as follows: 1) SCS trial only (n = 47), 2) successful SCS (implanted and in use throughout the two-year follow-up period, n = 131), and 3) unsuccessful SCS (implanted but later explanted or revised due to inadequate pain relief, n = 29). Patients who underwent explantation for other reasons (n = 4) were excluded. Opioid purchase data from January 1995 to March 2016 were retrieved from national registries.ResultsHigher preimplantation opioid doses associated with unsuccessful SCS (ROC: AUC = 0.66, p = 0.009), with 35 morphine milligram equivalents (MME)/day as the optimal cutoff value. All opioids were discontinued in 23% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.004). Strong opioids were discontinued in 39% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.04). Mean opioid dose escalated from 18 ± 4 MME/day to 36 ± 6 MME/day with successful SCS and from 22 ± 8 MME/day to 82 ± 21 MME/day with unsuccessful SCS (p < 0.001).ConclusionsHigher preimplantation opioid doses were associated with SCS failure, suggesting the need for opioid tapering before implantation. With continuous SCS therapy and no explantation or revision due to inadequate pain relief, 39% of FBSS patients discontinued strong opioids, and 23% discontinued all opioids. This indicates that SCS should be considered before detrimental dose escalation.  相似文献   
3.
The adrenal cortex gives rise to a biologically heterogenous group of neoplasms, each with a distinct morphology, antigen expression and molecular profile. Adrenal cortical adenomas have excellent prognosis and are usually cured by surgical resection alone, while adrenal cortical carcinomas are very aggressive tumors with a poor prognosis regardless of therapy. These tumors are rare and often challenging for a pathologist to diagnose, as significant overlap exists between benign and malignant lesions in some cases. In this review, we attempt to summarize most important histologic and clinical features of adrenal cortical adenomas and carcinomas, clarify the use of different grading systems, the use of special stains and the differential diagnosis for practicing pathologists. Most relevant hereditary syndromes associated with adrenal cortical tumors are listed. Updates in molecular alterations in adrenal cortical neoplasms and hyperplastic diseases as well as their clinical significance and potential therapeutic implications are also discussed.  相似文献   
4.
5.
6.
7.
Journal of Immigrant and Minority Health - COVID-19 has disproportionally affected underrepresented minorities (URM) and low-income immigrants in the United States. The aim of the study is to...  相似文献   
8.
Metformin, a drug for type 2 diabetes mellitus, has shown therapeutic effects for various cancers. However, it had no beneficial effects on the survival rate of human malignant mesothelioma (HMM) patients. The present study was performed to elucidate the underlying mechanism of metformin resistance in HMM cells. Glucose‐starved HMM cells had enhanced resistance to metformin, demonstrated by decreased apoptosis and autophagy and increased cell survival. These cells showed abnormalities in mitochondria, such as decreased ATP synthesis, morphological elongation, altered mitochondrial permeability transition pore and hyperpolarization of mitochondrial membrane potential (MMP). Intriguingly, Mdr1 was significantly upregulated in mitochondria but not in cell membrane. The upregulated mitochondrial Mdr1 was reversed by treatment with carbonyl cyanide m‐chlorophenyl hydrazone, an MMP depolarization inducer. Furthermore, apoptosis and autophagy were increased in multidrug resistance protein 1 knockout HMM cells cultured under glucose starvation with metformin treatment. The data suggest that mitochondrial Mdr1 plays a critical role in the chemoresistance to metformin in HMM cells, which could be a potential target for improving its therapeutic efficacy.  相似文献   
9.
10.
We report a case of benign lymphoplasmacytic plaque (LPP) in a child. These asymptomatic erythematous papulonodular lesions are an emerging clinicopathological entity. Herein, we describe a previously unreported site for LPP lesions, namely, the volar wrist and the distal ipsilateral palm.  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