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   5589篇
  免费   372篇
  国内免费   25篇
耳鼻咽喉   45篇
儿科学   175篇
妇产科学   133篇
基础医学   791篇
口腔科学   147篇
临床医学   512篇
内科学   1594篇
皮肤病学   91篇
神经病学   305篇
特种医学   92篇
外科学   637篇
综合类   56篇
一般理论   2篇
预防医学   408篇
眼科学   121篇
药学   304篇
  1篇
中国医学   46篇
肿瘤学   526篇
  2024年   6篇
  2023年   66篇
  2022年   90篇
  2021年   191篇
  2020年   96篇
  2019年   173篇
  2018年   163篇
  2017年   121篇
  2016年   118篇
  2015年   149篇
  2014年   199篇
  2013年   286篇
  2012年   473篇
  2011年   437篇
  2010年   271篇
  2009年   206篇
  2008年   343篇
  2007年   399篇
  2006年   351篇
  2005年   364篇
  2004年   343篇
  2003年   323篇
  2002年   259篇
  2001年   24篇
  2000年   16篇
  1999年   37篇
  1998年   40篇
  1997年   35篇
  1996年   47篇
  1995年   20篇
  1994年   32篇
  1993年   19篇
  1992年   14篇
  1991年   17篇
  1990年   13篇
  1989年   11篇
  1988年   19篇
  1987年   14篇
  1986年   12篇
  1985年   19篇
  1984年   17篇
  1983年   11篇
  1982年   10篇
  1981年   16篇
  1980年   19篇
  1978年   6篇
  1977年   7篇
  1976年   10篇
  1975年   10篇
  1971年   5篇
排序方式: 共有5986条查询结果,搜索用时 15 毫秒
81.
The progress with intensive chemotherapy and supportive care measures has improved survival in patients with newly diagnosed acute myeloid leukemia (AML). Given the recent development of effective low intensity therapies, an optimal decision on the therapy intensity may improve survival through the avoidance of early mortality. We reviewed the outcome of 3728 patients with newly diagnosed AML who received intensive chemotherapy between August 1980 and May 2020. Intensive chemotherapy was defined as a cumulative cytarabine dose ≥ 700 mg/m2 during induction therapy. We divided the whole cohort into a training and validation group at a 3:1 ratio. The population was divided into a training (2790 patients) and a validation cohort (938 patients). The median age was 55 years (range, 15-99). Among them, 442 patients (12%) had core-binding factor AML. Binary logistic regression identified older age, worse performance status, hyperbilirubinemia, elevated creatinine, hyperuricemia, cytogenetic abnormalities other than CBF and -Y, and pneumonia as adverse prognostic factors for an early 4-week mortality. This risk classification for early mortality was verified in the validation cohort of patients. In the validation cohort of more recently treated patients from 2000 to 2017, the 4-week mortality rates with intensive chemotherapy were 2%, 14%, and 50% in the low-, high-, and very high-risk group, respectively. The mortality rates with low intensity therapies were 3%, 9%, and 20%, respectively. The risk classification guides treatment intensity by the assessment of age, frailty, organ dysfunction, cytogenetic abnormality, and infection to avoid early mortality.  相似文献   
82.
The cascade of molecular events leading to Human apolipoprotein A–I (apoA–I) amyloidosis is not completely understood, not even the pathways that determine clinical manifestations associated to systemic protein deposition in organs such as liver, kidney and heart. About twenty natural variants of apoA–I were described as inducing amyloidosis, but the mechanisms driving their aggregation and deposition are still unclear. We previously identified that the mutant Gly26Arg but not Lys107-0 induced the release of cytokines and reactive oxygen species from cultured RAW 264.7 murine macrophages, suggesting that part of the pathogenic pathway could elicit of an inflammatory signal. In this work we gained deep insight into this mechanism and determined that Gly26Arg induced a specific pro-inflammatory cascade involving activation of NF-κB and its translocation into the nucleus. These findings suggest that some but not all apoA–I natural variants might promote a pro-oxidant microenvironment which could in turn result in oxidative processing of the variants into a misfolded conformation.  相似文献   
83.
During liver fibrogenesis the immune response and angiogenesis process are fine-tuned resulting in activation of hepatic stellate cells that produce an excess of extracellular matrix proteins. Dendritic cells (DC) play a central role modulating the liver immunity and have recently been implicated to favour fibrosis regression; although their ability to influence the development of fibrogenesis is unknown. Therefore, we explored whether the depletion of DC during early stages of liver injury has an impact in the development of fibrogenesis. Using the CD11c.DTR transgenic mice, DC were depleted in two experimental models of fibrosis in vivo. The effect of anti-angiogenic therapy was tested during early stages of liver fibrogenesis. DC depletion accelerates the development of fibrosis and as a consequence, the angiogenesis process is boosted. We observed up-regulation of pro-angiogenic factors together with an enhanced vascular endothelial growth factor (VEGF) bioavailability, mainly evidenced by the decrease of anti-angiogenic VEGF receptor 1 (also known as sFlt-1) levels. Interestingly, fibrogenesis process enhanced the expression of Flt-1 on hepatic DC and administration of sFlt-1 was sufficient to abrogate the acceleration of fibrogenesis upon DC depletion. Thus, DC emerge as novel players during the development of liver fibrosis regulating the angiogenesis process and thereby influencing fibrogenesis.  相似文献   
84.
85.
86.
87.
Dental treatment on Handicapped Patients is often difficult because many people with a wide range of ages (from children to the elderly) with different pathologies that can affect the oral cavity and differ widely are included in this group. This situation creates some controversy, because according to pathology, each patient will be treated differently depending on collaboration, general health status, age or medication used to treat this pathologies. According to this situation we can opt for an outpatient treatment without any kind of previous medication, a treatment under conscious or deep sedation or a under general anesthesia treatment. With this systematic review is intended to help clarify in which cases patients should be treated under general anesthesia, sedation (conscious or deep) or outpatient clinic without any medication, as well as clarify what kind of treatments can be carried in private dental clinics and which should be carried out in a hospital. It will also discuss the most common diseases among this group of patients and the special care to be taken for their dental treatment. Key words:Hospital dentistry, handicapped patient.  相似文献   
88.
Abstract

In the present study, we report that an intense bFGF-immunoreactivity has been detected in the choroid plexus of the brain ventricles of adult rats. These results suggest that epithelial choroid plexus cells may be the source of the cerebrospinal fluid bFGF. [Neurol Res 1994; 16: 310-312]  相似文献   
89.
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