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   1352543篇
  免费   96967篇
  国内免费   3098篇
耳鼻咽喉   20207篇
儿科学   41401篇
妇产科学   39169篇
基础医学   188889篇
口腔科学   40778篇
临床医学   113985篇
内科学   265716篇
皮肤病学   30727篇
神经病学   107459篇
特种医学   54619篇
外国民族医学   437篇
外科学   211713篇
综合类   31546篇
现状与发展   7篇
一般理论   443篇
预防医学   92753篇
眼科学   31884篇
药学   101202篇
  7篇
中国医学   3209篇
肿瘤学   76457篇
  2018年   12368篇
  2016年   11263篇
  2015年   12534篇
  2014年   17565篇
  2013年   26360篇
  2012年   34328篇
  2011年   36202篇
  2010年   21516篇
  2009年   20738篇
  2008年   34647篇
  2007年   37792篇
  2006年   38352篇
  2005年   37073篇
  2004年   36192篇
  2003年   35137篇
  2002年   34551篇
  2001年   64184篇
  2000年   65857篇
  1999年   55705篇
  1998年   14800篇
  1997年   13568篇
  1996年   13033篇
  1995年   12269篇
  1994年   11517篇
  1992年   42807篇
  1991年   41323篇
  1990年   40580篇
  1989年   39585篇
  1988年   36993篇
  1987年   36435篇
  1986年   34921篇
  1985年   33120篇
  1984年   24836篇
  1983年   21061篇
  1982年   12678篇
  1981年   11576篇
  1979年   23936篇
  1978年   17078篇
  1977年   14843篇
  1976年   13390篇
  1975年   15271篇
  1974年   18090篇
  1973年   17567篇
  1972年   16822篇
  1971年   15723篇
  1970年   14919篇
  1969年   14353篇
  1968年   13463篇
  1967年   12023篇
  1966年   11264篇
排序方式: 共有10000条查询结果,搜索用时 375 毫秒
51.
52.
53.
54.
Abstract

We have investigated communication preferences of mammography results in 90 patients through a structured interview approach. About 81% of patients expressed that they wanted to get the results, and 18% expressed that getting the results does not help if they are incomprehensible. In patients who want to get the results, 80% preferred face-to-face interaction with physicians, whereas the others preferred other modes of communication to prevent loss of time. Majority of patients infavor of face-to-face interaction (57%) preferred both the referring physician and the radiologist. Comprehensibility and fast delivery of reports, plus direct communication with radiologists are the requirements in mammography patients while implementing patient-centered radiology.  相似文献   
55.
56.
Esophageal adenocarcinoma is the fastest rising cancer in the United States. It develops from long‐standing gastroesophageal reflux disease which affects >20% of the general population. It carries a very poor prognosis with 5‐year survival <20%. The disease is known to sequentially progress from reflux esophagitis to a metaplastic precursor, Barrett''s esophagus and then onto dysplasia and esophageal adenocarcinoma. However, only few patients with reflux develop Barrett''s esophagus and only a minority of these turn malignant. The reason for this heterogeneity in clinical progression is unknown. To improve patient management, molecular changes which facilitate disease progression must be identified. Animal models can provide a comprehensive functional and anatomic platform for such a study. Rats and mice have been the most widely studied but disease homology with humans has been questioned. No animal model naturally simulates the inflammation to adenocarcinoma progression as in humans, with all models requiring surgical bypass or destruction of existing antireflux mechanisms. Valuable properties of individual models could be utilized to holistically evaluate disease progression. In this review paper, we critically examined the current animal models of Barrett''s esophagus, their differences and homologies with human disease and how they have shaped our current understanding of Barrett''s carcinogenesis.  相似文献   
57.
Mitochondria are known primarily as the location of the electron transport chain and energy production in cells. More recently, mitochondria have been shown to be signaling centers for apoptosis and inflammation. Reactive oxygen species (ROS) generated as by-products of the electron transport chain within mitochondria significantly impact cellular signaling pathways. Because of the toxic nature of ROS, mitochondria possess an antioxidant enzyme, superoxide dismutase 2 (SOD2), to neutralize ROS. If mitochondrial antioxidant enzymes are overwhelmed during severe infections, mitochondrial dysfunction can occur and lead to multiorgan failure or death. Pseudomonas aeruginosa is an opportunistic pathogen that can infect immunocompromised patients. Infochemicals and exotoxins associated with P. aeruginosa are capable of causing mitochondrial dysfunction. In this work, we describe the roles of SOD2 and mitochondrial ROS regulation in the zebrafish innate immune response to P. aeruginosa infection. sod2 is upregulated in mammalian macrophages and neutrophils in response to lipopolysaccharide in vitro, and sod2 knockdown in zebrafish results in an increased bacterial burden. Further investigation revealed that phagocyte numbers are compromised in Sod2-deficient zebrafish. Addition of the mitochondrion-targeted ROS-scavenging chemical MitoTEMPO rescues neutrophil numbers and reduces the bacterial burden in Sod2-deficient zebrafish. Our work highlights the importance of mitochondrial ROS regulation by SOD2 in the context of innate immunity and supports the use of mitochondrion-targeted ROS scavengers as potential adjuvant therapies during severe infections.  相似文献   
58.
Pancreatic ductal adenocarcinoma (PDAC) is predicted to become the second leading cause of cancer-related mortality within the next decade, with limited effective treatment options and a dismal long-term prognosis for patients. Genomic profiling has not yet manifested clinical benefits for diagnosis, treatment or prognosis in PDAC, due to the lack of available tissues for sequencing and the confounding effects of low tumour cellularity in many biopsy specimens. Increasing focus is now turning to the use of minimally invasive liquid biopsies to enhance the characterisation of actionable PDAC tumour genomes. Circulating tumour DNA (ctDNA) is the most comprehensively studied liquid biopsy analyte in blood and can provide insight into the molecular profile and biological characteristics of individual PDAC tumours, in real-time and in advance of traditional imaging modalities. This can pave the way for identification of new therapeutic targets, novel risk variants and markers of tumour response, to supplement diagnostic screening and provide enhanced scrutiny in treatment stratification. In the roadmap towards the application of precision medicine for clinical management in PDAC, ctDNA analyses may serve a leading role in streamlining candidate biomarkers for clinical integration. In this review, we highlight recent developments in the use of ctDNA-based liquid biopsies for PDAC and provide new insights into the technical, analytical and biological challenges that must be overcome for this potential to be realised.  相似文献   
59.
60.
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