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   103691篇
  免费   9441篇
  国内免费   6085篇
耳鼻咽喉   1230篇
儿科学   1290篇
妇产科学   1074篇
基础医学   12945篇
口腔科学   1743篇
临床医学   11952篇
内科学   15442篇
皮肤病学   1660篇
神经病学   5183篇
特种医学   4771篇
外国民族医学   40篇
外科学   10380篇
综合类   15966篇
现状与发展   31篇
一般理论   9篇
预防医学   6751篇
眼科学   3107篇
药学   11159篇
  90篇
中国医学   5255篇
肿瘤学   9139篇
  2024年   213篇
  2023年   1195篇
  2022年   3324篇
  2021年   4666篇
  2020年   3377篇
  2019年   3127篇
  2018年   3285篇
  2017年   3078篇
  2016年   3168篇
  2015年   4788篇
  2014年   5937篇
  2013年   5794篇
  2012年   8514篇
  2011年   9062篇
  2010年   5996篇
  2009年   5140篇
  2008年   6246篇
  2007年   6056篇
  2006年   5744篇
  2005年   5161篇
  2004年   3797篇
  2003年   3719篇
  2002年   3134篇
  2001年   2223篇
  2000年   1998篇
  1999年   1867篇
  1998年   1202篇
  1997年   1095篇
  1996年   921篇
  1995年   804篇
  1994年   744篇
  1993年   497篇
  1992年   571篇
  1991年   481篇
  1990年   424篇
  1989年   377篇
  1988年   266篇
  1987年   279篇
  1986年   221篇
  1985年   144篇
  1984年   97篇
  1983年   72篇
  1982年   59篇
  1981年   50篇
  1980年   33篇
  1979年   30篇
  1976年   17篇
  1975年   16篇
  1974年   16篇
  1973年   18篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
目的研究医学教育如何将人文精神内化于心,为医疗实践提供思路和方向。方法以《惠世医学人文素养》课程为载体,将心理营养教育融入人文教育,整体化教学整合人文和医学;应用Kirkpatrick模型从反应、学习、行为和结果等4个层次分析课程的教学效果。结果学生对课程满意度高;课程学习后学生增强了信息管理能力、团队合作能力、语言表达能力、自我发展能力等,提高了专业认知度,加强了职业认同感,在技能考核中展现了良好的人文关怀精神和优良的职业素质。结论《惠世医学人文素养》课程作为医学人文教育模式创新的有益尝试,有助于提高医学人文教育的有效性和针对性。  相似文献   
972.
心房纤颤(atrial fibrillation, AF)是临床上最常见的心律失常之一,也是心血管疾病发病率和死亡率增加的重要原因。心外膜脂肪(epicardial adipose tissue, EAT)是位于脏层心包和心肌之间的一种特殊脂肪组织,研究表明EAT参与AF的发生与维持,但是具体机制尚未得到完全阐释。EAT来源的脂肪干细胞(adipose-derived stromal cells, ADSCs)分泌的细胞外囊泡(extracellular vesicles, EVs) 近年来受到重视。该文主要从EAT特点、定量检测及其与心肌结构与电重构的关系,特别是EVs对AF发生的影响等方面进行综述,以期进一步认识AF的发病机制,为今后的治疗提供新的思路。  相似文献   
973.
We report the prevalence rates for dementia and Alzheimer's disease (AD) obtained from a probability sample survey of 5,055 noninstitutionalized older persons in Shanghai, China. A two-stage procedure was used for case finding and case identification. A Chinese version of the Mini-Mental State Examination was used to determine cases of possible dementia. Three different cutoff points on this mental status test were used depending on the respondent's level of education. Clinical evaluations, based on functional assessments and psychiatric interview, medical and neurological examinations, three standardized mental status tests, and a selected group of psychometric tests, were made in the second stage of the study to ascertain the clinical diagnosis of dementia and AD utilizing the Diagnostic and Statistical Manual for Mental Disorders, edition 3 and National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria, respectively. The prevalence rate of dementia in persons 65 years and older was 4.6%. Clinically diagnosed AD accounted for 65% of the subjects with dementia. These findings indicate that the prevalence of dementia in Shanghai is very much higher than figures published earlier for China and Japan, and at the lower part of the range of values reported for community residents in the United States and other Western countries, but less than half of that reported in the recently published survey of the elderly in East Boston. Increasing age, gender (female), and low education are each highly significant and independent risk factors for dementia. One hypothesis to explain the increased prevalence in elderly women who had received no formal education invokes the possibility of an effect of early deprivation, perhaps lowering brain "reserve," allowing the symptoms of dementia to appear at an earlier date during disease progression.  相似文献   
974.
A pseudotumor appearance of the liver has not been previously described in chronic hepatitis. We reviewed 81 charts with a biopsy diagnosis of "chronic hepatitis" and at least one radiologic liver scan, and found four cases with a pseudotumor appearance. They all had features on radiologic scans suggestive of space-occupying lesions. Histology showed chronic hepatitis in all four. Two were cirrhotic, one due to alcohol and the other due to hepatitis B. The other two patients had chronic active hepatitis with regenerative nodules but only limited fibrosis, one due to hepatitis B, the other probable non-A, non-B. None had any evidence of hepatic malignancy. We conclude that some patients with chronic hepatitis may present with a pseudotumor appearance on radiological scans, due to the presence of regenerative nodules. Space-occupying lesions on liver scans in chronic hepatitis may represent non-neoplastic liver disease.  相似文献   
975.
976.
模糊聚类法分析头孢菌素结构及其免疫交叉反应的关系   总被引:1,自引:0,他引:1  
  相似文献   
977.
鬼针草的细胞学研究   总被引:1,自引:0,他引:1  
报道了鬼针草的核型公式:K(2n)=3X=36=27m+3sm+6sm(SAT),染色体相对长度组成:2n=36=6L+9M2+18M1+3S,核型为“2A”型,同时计算了鬼针草的染色体体积。  相似文献   
978.
低血流心肌缺血诱导GLUT4基因表达   总被引:1,自引:0,他引:1  
目的:探讨低血流心肌缺血促进葡萄糖摄取增加的机制。方法:采用Northrn印迹法观察缺血心肌葡萄转运子4(GLUT4)mRNA的表达,并利用蛋白质印迹法分析心肌GLUT4多肽的表达,结果:局部心肌低血流缺血后,心肌GLUT4mRNA和GLUT4多肽表达明显增加;同时伴随缺血心肌葡萄糖摄取明显增多。结论:心肌缺血能刺激GLUT4 mRNA和GLUT4多肽表达,使GLUT4数增加,进而促进心肌葡萄糖摄取增多,使缺血心肌能量需求得以平衡,有助于缺血心肌功能的恢复,提示低血流缺 刺激心肌GLUT4表达是一个重要的代偿性保护机制。  相似文献   
979.
探讨磁化支架对经皮经腔冠状埃及成形术 (PTCA)后冠状动脉再狭窄的防治作用。方法  2 0只健康杂种犬 ,超大球囊反复扩张损伤靶血管 (前降支或旋支中段 )制备PTCA术后冠状动脉狭窄模型(>5 0 % ) ,后随机分成对照组和实验组各 10只。对照组靶血管置入普通Palmaz支架 ,实验组靶血管置入磁化Palmaz支架。手术前后不用抗血小板药和抗凝药 ,术后 6个月冠状动脉造影 ,并处死犬切取靶血管 3cm进行组织病理学检查。结果 冠状动脉造影冠状动脉再狭窄率对照组 30 % ,实验组 0 ;组织病理学检查靶血管平均内膜厚度 (对照组 2 .98± 0 .5 6mm) ,(实验组 1.13± 0 .4 1mm)有显著差异 ,P <0 .0 5。结论 磁化支架对犬PTCA术后冠状动脉再狭窄可能具有防治作用。  相似文献   
980.
Objective To clarify the role of sexual related Y (SRY) gene detection in the diagnosis of gonadal dysgenesis.Methods Sixteen cases of gonadal dysgenesis were included in this study: 5 with androgen insensitivity syndrome, 1 with 17-α-hydroxylase deficiency, 4 with true herm aphrodite, 2 with 45,X/46,XY gonadal dysgenesis, 1 with 45,X gonadal dysgenesis, 1 with XY pure gonadal dysgenesis, 1 with testicular regression, and 1 XY fema le who gave birth to a normal baby. SRY gene was detected by using polymerase c hain reaction (PCR) in blood and gonad samples and by direct sequencing of the S RY motif. Results Among the 16 cases, 15 were blood SRY positive, among which 13 (86.7%) showed t he presence of testicular tissue, and 2 showed ovaries without testicular tissue . One SRY negative case showed the presence of testicular tissue. In 3 cases, SRY detection in gonadal tissue correlated with pathological findings but not wi th blood karyotype. The correlation between peripheral blood SRY and the pathol ogy of the gonads was 81.25% and the correlation between the presence of periph eral blood Y chromosome and pathology of the gonads was 68.75%. Sequencing of the SRY motif in an XY female who gave birth to a normal baby showed no mutatio n.Conclusions SRY detection is more sensitive and specific than blood karyotype in the predic tion of the presence of testicular tissue. Peripheral blood karyotype does not necessarily reflect gonadal type. There may be testicular related factors other than the SRY gene.  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