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   134326篇
  免费   11455篇
  国内免费   8120篇
耳鼻咽喉   1167篇
儿科学   1998篇
妇产科学   1270篇
基础医学   14357篇
口腔科学   2330篇
临床医学   17287篇
内科学   18364篇
皮肤病学   1853篇
神经病学   5995篇
特种医学   5076篇
外国民族医学   45篇
外科学   12124篇
综合类   25636篇
现状与发展   31篇
一般理论   11篇
预防医学   11579篇
眼科学   3050篇
药学   14240篇
  112篇
中国医学   7706篇
肿瘤学   9670篇
  2024年   320篇
  2023年   1425篇
  2022年   3734篇
  2021年   5036篇
  2020年   3892篇
  2019年   3252篇
  2018年   3468篇
  2017年   3479篇
  2016年   3525篇
  2015年   5542篇
  2014年   7155篇
  2013年   7336篇
  2012年   10752篇
  2011年   11496篇
  2010年   8624篇
  2009年   7429篇
  2008年   8750篇
  2007年   8787篇
  2006年   8155篇
  2005年   7541篇
  2004年   5658篇
  2003年   5698篇
  2002年   4607篇
  2001年   3709篇
  2000年   3007篇
  1999年   2266篇
  1998年   1376篇
  1997年   1379篇
  1996年   1003篇
  1995年   887篇
  1994年   737篇
  1993年   469篇
  1992年   569篇
  1991年   455篇
  1990年   399篇
  1989年   341篇
  1988年   325篇
  1987年   259篇
  1986年   213篇
  1985年   190篇
  1984年   111篇
  1983年   87篇
  1982年   66篇
  1981年   51篇
  1980年   30篇
  1979年   55篇
  1978年   39篇
  1976年   24篇
  1973年   29篇
  1971年   22篇
排序方式: 共有10000条查询结果,搜索用时 26 毫秒
31.
步宏  李锋 《华西医学》1991,6(2):234-237
随机选择经长期随访证实的滤泡性甲状腺癌和腺瘤各10例,正常甲状腺组织5例作为对照。按Ploton的染色方法和Crocker推荐的计数方法分别计算三组每例各50个细胞的Ag-NOR嗜银颗粒平均数,再算出三组各自的AgNOR均数,经统计学检验三者有极显著性差异。可望成为甲状腺滤泡性肿瘤良恶鉴别的一项辅助指标。  相似文献   
32.
The purpose of the present study was to determine the reliability of several selected signs of trauma from occlusion and their relations with severity of periodontitis. 32 moderate to advanced chronic periodontitis patients participated in the study. All teeth present were evaluated for various abnormal occlusal contacts, signs of trauma from occlusion, and the severity of periodontitis. Standardized periapical radiographs were also taken for each tooth. The results demonstrated that: (1) no significant difference occurred in probing pocket depth (PD), clinical attachment loss (AL), or percentage of alveolar bone height (BH) between teeth with and without various abnormal occlusal contacts, i.e., premature contacts in centric relation occlusion, non-working contacts in lateral excursions, premature contacts of anterior teeth or posterior protrusive tooth contacts; (2) teeth with either significant mobility, functional mobility, or radiographically widened periodontal ligament space (PDLS) had deeper PD, more AL and lower BH than teeth without these signs, while teeth with pronounced wear or radiographically thickened lamina dura had less AL than teeth without these findings; (3) 2 combined indices, i.e., the trauma from occlusion index (TOI) and the adaptability index (AI), were proposed for the identification of occlusal trauma and the response of periodontium to excessive biting forces in heavy function, respectively; TOI-positive teeth exhibit deeper PD, more AL and less osseous support than TOI-negative teeth; however, AI-positive teeth had less AL and more osseous support than AI-negative teeth; (4) with identical attachment level, TOI-positive teeth had less osseous support than TOI-negative teeth while the magnitude of difference became greater with an increase of attachment loss.  相似文献   
33.
目的 观察急性脑梗死 (ACI)后血浆一氧化氮 (NO)、一氧化氮合成酶 (NOS)、内皮素 (ET)含量的动态变化 ,以及尼莫地平治疗后对其影响。方法 ACI患者 110例 ,随机分成尼莫地平组 (5 0例 ) (在常规治疗基础上用尼莫地平 )和常规治疗组 (6 0例 )。在发病后不同时点动态观察血浆NO、NOS、ET含量 ,并设 5 0例脑动脉硬化患者为对照组。结果 脑梗死后血浆ET含量显著升高 ,直至恢复期 ;NO、NOS先增高后下降 ;尼莫地平组和常规组比较ET有显著差异 (P <0 .0 1) ,NO、NOS差别不显著 (P >0 .0 5 )。结论 NO、NOS、ET参与并影响了ACI后复杂的病理生理过程 ;尼莫地平部分通过对ET含量的影响发挥其对脑梗死的治疗作用  相似文献   
34.
高血压病治疗的药物选择是临床医生需要综合考虑的问题,现将我院应用美托洛尔控释片对中青年高血压病进行治疗的观察结果和体会总结如下。  相似文献   
35.
36.
Background:Defecation of patients with rectal carcinoma after operation cannot be controlled freely,which brings patients many mental burdens.Cocolyster operation can improve obviously the symptom.  相似文献   
37.
38.
Summary To investigate the distribution of possible novel mutations from parkin gene in variant subset of patients with Parkinson’s disease (PD) in China and explore whether parkin gene plays an important role in the pathogenesis of PD, 70 patients were divided into early-onset group and late-onset group; 70 healthy subjects were included as controls. Genomic DNA from 70 normal controls and from those of PD patients were extracted from peripheral blood leukocytes by using standard procedures. Mutations of parkin gene (exon 1–12) in all the subjects were screened by PCR-single strand conformation polymorphism (SSCP), and further sequencing was performed in the samples with abnormal SSCP results, in order to confirm the mutation and its location. A new missense mutation Gly284Arg in a patient and 3 abnormal bands in SSCP electrophoresis from samples of another 3 patients were found. All the DNA variants were sourced from the samples of the patients with early-onset PD. It was concluded that Parkin point mutation also partially contributes to the development of early-onset Parkinson’s disease in Chinese. WANG Tao, male, born in 1961, Associate Professor This work was supported by grants from the key program of the special scientific project of Scientific & Technologic Agency of Hubei Province (Serial No. 2001AA308B01) and the Hygienic Research Project of Hygienic Agency of Hubei province (Serial No. WJ 01529).  相似文献   
39.
The paper describes the prenatal ultrasonographic diagnosis of conjoined syncephalus-craniothoraco-omphalopagus twins at 13 weeks' gestation. The mother, after genetic counseling, decided to interrupt the pregnancy. The fetal karyotype, the maternal serum and amniotic fluid alpha-fetoprotein levels were normal. The diagnosis was confirmed by pathologic examination of the fetus after termination of pregnancy.  相似文献   
40.
陈红 《现代医院》2007,7(8):68-69
目的探讨脑出血急性期心电图异常的表现及特征。方法回顾分析220例住院各类急性脑出血患者的心电图资料,并分析其特点及与脑出血的关系。结果脑出血后继发心电图改变主要表现为ST-T改变和(或)心律失常。结论脑出血心电图异常与疾病的严重程度密切相关。心电图的异常可随脑血管病情的减轻而好转或消失,并对脑血管病情的预后有积极的意义。对高龄、高血压病等具缺血性心脏病的危险因素的人群,应加强监护。  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