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   1352746篇
  免费   110780篇
  国内免费   28025篇
耳鼻咽喉   15733篇
儿科学   39174篇
妇产科学   32569篇
基础医学   184474篇
口腔科学   33645篇
临床医学   140941篇
内科学   239373篇
皮肤病学   26863篇
神经病学   96261篇
特种医学   51855篇
外国民族医学   528篇
外科学   180572篇
综合类   92933篇
现状与发展   86篇
一般理论   415篇
预防医学   103489篇
眼科学   32923篇
药学   111398篇
  425篇
中国医学   26242篇
肿瘤学   81652篇
  2022年   10467篇
  2021年   24607篇
  2020年   18455篇
  2019年   18742篇
  2018年   22421篇
  2017年   19696篇
  2016年   19873篇
  2015年   27096篇
  2014年   35007篇
  2013年   40724篇
  2012年   56759篇
  2011年   62177篇
  2010年   39672篇
  2009年   34653篇
  2008年   49731篇
  2007年   51125篇
  2006年   50690篇
  2005年   48508篇
  2004年   41342篇
  2003年   39774篇
  2002年   36607篇
  2001年   54962篇
  2000年   55871篇
  1999年   48233篇
  1998年   16306篇
  1997年   15062篇
  1996年   14049篇
  1995年   13439篇
  1994年   12178篇
  1993年   10466篇
  1992年   34475篇
  1991年   33429篇
  1990年   32683篇
  1989年   31312篇
  1988年   28352篇
  1987年   28352篇
  1986年   26250篇
  1985年   25199篇
  1984年   18701篇
  1983年   15707篇
  1979年   16962篇
  1978年   12256篇
  1977年   10331篇
  1976年   9747篇
  1975年   10176篇
  1974年   12336篇
  1973年   11858篇
  1972年   10909篇
  1971年   10122篇
  1970年   9388篇
排序方式: 共有10000条查询结果,搜索用时 119 毫秒
81.
82.
Bipolar disorder (BD) is a common psychiatric mood disorder affecting more than 1-2% of the general population of different European countries. Unfortunately, there is no objective laboratory-based test to aid BD diagnosis or monitor its progression, and little is known about the molecular basis of BD. Here, we performed a comparative proteomic study to identify differentially expressed plasma proteins in various BD mood states (depressed BD, manic BD, and euthymic BD) relative to healthy controls. A total of 10 euthymic BD, 20 depressed BD, 15 manic BD, and 20 demographically matched healthy control subjects were recruited. Seven high-abundance proteins were immunodepleted in plasma samples from the 4 experimental groups, which were then subjected to proteome-wide expression profiling by two-dimensional electrophoresis and matrix-assisted laser desorption/ionization-time-of-flight/time-of-flight tandem mass spectrometry. Proteomic results were validated by immunoblotting and bioinformatically analyzed using MetaCore. From a total of 32 proteins identified with 1.5-fold changes in expression compared with healthy controls, 16 proteins were perturbed in BD independent of mood state, while 16 proteins were specifically associated with particular BD mood states. Two mood-independent differential proteins, apolipoprotein (Apo) A1 and Apo L1, suggest that BD pathophysiology may be associated with early perturbations in lipid metabolism. Moreover, down-regulation of one mood-dependent protein, carbonic anhydrase 1 (CA-1), suggests it may be involved in the pathophysiology of depressive episodes in BD. Thus, BD pathophysiology may be associated with early perturbations in lipid metabolism that are independent of mood state, while CA-1 may be involved in the pathophysiology of depressive episodes.  相似文献   
83.
Hepatic NADPH-cytochrome P450 oxidoreductase null (HRN?) mice exhibit normal hepatic and extrahepatic biotransformation enzyme activities when compared to wild-type (WT) mice, but express no functional hepatic cytochrome P450 activities. When incubated in vitro with [14C]-diclofenac, liver microsomes from WT mice exhibited extensive biotransformation to oxidative and glucuronide metabolites and covalent binding to proteins was also observed. In contrast, whereas glucuronide conjugates and a quinone-imine metabolite were formed when [14C]-diclofenac was incubated with HRN? mouse liver, only small quantities of P450-derived oxidative metabolites were produced in these samples and covalent binding to proteins was not observed. Livers from vehicle-treated HRN? mice exhibited enhanced lipid accumulation, bile duct proliferation, hepatocellular degeneration and necrosis and inflammatory cell infiltration, which were not present in livers from WT mice. Elevated liver-derived alanine aminotransferase, glutamate dehydrogenase and alkaline phosphatase activities were also observed in plasma from HRN? mice. When treated orally with diclofenac for 7 days, at 30 mg/kg/day, the severities of the abnormal liver histopathology and plasma liver enzyme findings in HRN? mice were reduced markedly. Oral diclofenac administration did not alter the liver histopathology or elevate plasma enzyme activities of WT mice. These findings indicate that HRN? mice are valuable for exploration of the role played by hepatic P450s in drug biotransformation, but poorly suited to investigations of drug-induced liver toxicity. Nevertheless, studies in HRN? mice could provide novel insights into the role played by inflammation in liver injury and may aid the evaluation of new strategies for its treatment.  相似文献   
84.
Introduction: To increase students’ understanding of what it means to be a physician and engage in the everyday practice of medicine, a humanities program was implemented into the preclinical curriculum of the medical school curriculum. The purpose of our study was to determine how medical students’ views of being a doctor evolved after participating in a required humanities course.

Methods: Medical students completing a 16-clock hour humanities course from 10 courses were asked to respond to an open-ended reflection question regarding changes, if any, of their views of being a doctor. The constant comparative method was used for coding; triangulation and a variety of techniques were used to provide evidence of validity of the analysis.

Results: A majority of first- and second-year medical students (rr?=?70%) replied, resulting in 100 pages of text. A meta-theme of Contextualizing the Purpose of Medicine and three subthemes: the importance of Treating Patients Rather than a Disease, Understanding Observation Skills are Important, and Recognizing that Doctors are Fallible emerged from the data.

Conclusions: Results suggest that requiring humanities as part of the required preclinical curriculum can have a positive influence on medical students and act as a bridge to contextualize the purpose of medicine.  相似文献   
85.
86.
目的以基因表达数据集资料为研究对象,分析BCAN基因在肾透明细胞癌中的表达情况以及对患者预后的影响。方法在Oncomine数据库中挖掘BCAN在肾透明细胞癌(ccRCC)中的表达情况。从TCGA数据库中获取ccRCC患者临床资料和目的基因的表达信息并进行统计分析。利用GEO数据库中GSE73731数据集的ccRCC样本进行基因富集分析。利用String数据库分析与BCAN相关的蛋白。结果BCAN低表达组的ccRCC患者在病理分期及T分期方面低于高表达组(P<0.001;P=0.001);N分期及M分期差异无统计学意义(P>0.05)。BCAN低表达组患者的总生存期优于高表达组(P=0.033)。BCAN基因高表达组的样本主要富集在KRAS信号通路。结论BCAN可以通过多种途径来促进肿瘤细胞的侵袭能力,有望成为ccRCC不良预后的重要生物标志物之一。  相似文献   
87.
患者男,64岁,因头颅增大、面部变长,颧骨隆起、下颌增大、双手掌肥厚、双手指粗短30余年,乳房肿物1年余就诊。患者30余年前无明显诱因出现渐进性手足增大,双手掌肥厚,嘴唇变厚,下颌增大,眉弓及颧骨突出,皮肤增厚,无乳腺增大、泌乳,未诊治……  相似文献   
88.
皮肤损伤后的异常愈合会导致病理性瘢痕的产生。病理性瘢痕的出现不仅影响美观,严重时还会造成心理和生理功能障碍。病理性瘢痕的机制研究对于瘢痕治疗有极为重要的意义。其中,动物瘢痕模型是目前研究病理性瘢痕的重要模型手段之一。理想的动物瘢痕模型应该在组织学、细胞学等层面尽可能接近于人类的病理性瘢痕。该文分别从传统技术动物瘢痕中的啮齿类动物模型、兔耳模型和猪模型,以及新技术动物瘢痕模型这两个方面,结合近年来在瘢痕领域应用较多的研究,进行了相应系统的阐述。  相似文献   
89.
脑卒中患者在面对复杂的治疗期、漫长的康复期及难以预测的病情变化时容易产生对疾病或疾病进展的恐惧。恐惧疾病进展会损害脑卒中患者的身心健康和社会功能,最终影响患者的康复和预后。从恐惧疾病进展的定义、测量工具、国内外研究现状及影响因素几个方面进行综述,为临床护理人员深入了解脑卒中患者恐惧疾病进展现状、开展相关护理实践和临床研究提供依据。  相似文献   
90.
目的 探讨模拟诊疗在留学生心血管内科实习带教中的应用效果。方法 将35名留学生随机编号,分成试验组和对照组。试验组18名学生分成3组(每组6名)进行模拟诊疗教学,对照组17名学生进行常规实习。通过填写评价单和相关的临床能力测试对两组教学效果进行评价。选用SPSS 19.0软件进行t检验。结果 参与模拟诊疗教学的留学生均希望在各科实习中多采用此方法。在临床能力测试方面,试验组学生在病史采集[(22.16±2.17)vs.(20.33±2.03)]、体格检查[(23.05±1.79)vs.(19.78±2.05)]及回答问题[(23.50±1.47)vs.(19.56±1.92)]方面均优于对照组,差异有统计学意义(P<0.05)。但是在病历书写方面,两组差异无统计学意义(P>0.05)。结论 利用高仿真的模拟诊疗教学手段,弥补了留学生在实习期间不能充分接触患者的缺陷,有助于提高其临床操作技能、增强医患沟通能力等医学职业素养。  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