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   1410229篇
  免费   115856篇
  国内免费   3334篇
耳鼻咽喉   18378篇
儿科学   46658篇
妇产科学   41071篇
基础医学   201083篇
口腔科学   37706篇
临床医学   126153篇
内科学   284659篇
皮肤病学   33379篇
神经病学   117107篇
特种医学   53923篇
外国民族医学   474篇
外科学   210704篇
综合类   32766篇
现状与发展   3篇
一般理论   488篇
预防医学   110171篇
眼科学   31503篇
药学   98600篇
  1篇
中国医学   3348篇
肿瘤学   81244篇
  2021年   10878篇
  2019年   11697篇
  2018年   16627篇
  2017年   12696篇
  2016年   14300篇
  2015年   16045篇
  2014年   22608篇
  2013年   33460篇
  2012年   45489篇
  2011年   48018篇
  2010年   28226篇
  2009年   27116篇
  2008年   44402篇
  2007年   46940篇
  2006年   47493篇
  2005年   45946篇
  2004年   43826篇
  2003年   41774篇
  2002年   40260篇
  2001年   73059篇
  2000年   74586篇
  1999年   61620篇
  1998年   17012篇
  1997年   15451篇
  1996年   15597篇
  1995年   14804篇
  1994年   13408篇
  1993年   12594篇
  1992年   45862篇
  1991年   43509篇
  1990年   41535篇
  1989年   39587篇
  1988年   36228篇
  1987年   35376篇
  1986年   32902篇
  1985年   31316篇
  1984年   23856篇
  1983年   20061篇
  1982年   12234篇
  1981年   10794篇
  1979年   20728篇
  1978年   14599篇
  1977年   12102篇
  1976年   11379篇
  1975年   11639篇
  1974年   14010篇
  1973年   13543篇
  1972年   12651篇
  1971年   11483篇
  1970年   10924篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
Guidelines and consensus on the management of patients with acne aim to give evidence-based, expert-group recommendations. This review compares current guidelines and consensus articles to provide a compilation of recommendations on the treatment of acne with oral isotretinoin. Ten common, relevant, clinical questions are addressed, based on published recommendations, including the indications of isotretinoin, the proposed daily dose, the cumulative isotretinoin dose and the laboratory monitoring needed. Recommendations on special considerations are also addressed, including the timing of procedures and the question of an association of depression or inflammatory bowel disease with isotretinoin. A major limitation is the use of different classification systems for acne across guidelines. The recommended daily dose ranges from 0.3 to 0.5 mg/kg in the European guidelines to up to 1 mg/kg in the US guidelines. A specific duration of treatment of at least 6 months is only recommended in the European guidelines. All guidelines report the need of strict pregnancy prevention measures. The European, French and US guidelines recommend to monitor for symptoms of depression. Important clinical questions that are inconsistently addressed in guidelines include the age indication, the recommendation for a cumulative dose, the timing of procedures, the association of isotretinoin with IBD, the recommendation for preventing acne flares and for appropriate laboratory monitoring. These topics should be clearly included in the recommendations of guidelines as they are often raised in everyday clinical practice.  相似文献   
83.
84.
85.
86.
87.
88.
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   
89.
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   
90.
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