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   53181篇
  免费   5383篇
  国内免费   3749篇
耳鼻咽喉   508篇
儿科学   450篇
妇产科学   481篇
基础医学   5468篇
口腔科学   780篇
临床医学   6792篇
内科学   7259篇
皮肤病学   390篇
神经病学   2582篇
特种医学   2064篇
外国民族医学   22篇
外科学   5836篇
综合类   10623篇
现状与发展   6篇
一般理论   6篇
预防医学   4051篇
眼科学   1491篇
药学   5820篇
  63篇
中国医学   3633篇
肿瘤学   3988篇
  2024年   271篇
  2023年   960篇
  2022年   2416篇
  2021年   3056篇
  2020年   2437篇
  2019年   1860篇
  2018年   1978篇
  2017年   1813篇
  2016年   1802篇
  2015年   2674篇
  2014年   3290篇
  2013年   3170篇
  2012年   4774篇
  2011年   4901篇
  2010年   3461篇
  2009年   2764篇
  2008年   3022篇
  2007年   2952篇
  2006年   2699篇
  2005年   2428篇
  2004年   1557篇
  2003年   1371篇
  2002年   1103篇
  2001年   864篇
  2000年   751篇
  1999年   782篇
  1998年   448篇
  1997年   444篇
  1996年   364篇
  1995年   302篇
  1994年   274篇
  1993年   158篇
  1992年   173篇
  1991年   151篇
  1990年   149篇
  1989年   114篇
  1988年   109篇
  1987年   99篇
  1986年   82篇
  1985年   65篇
  1984年   49篇
  1983年   33篇
  1982年   17篇
  1981年   14篇
  1980年   14篇
  1979年   15篇
  1978年   16篇
  1974年   9篇
  1973年   8篇
  1969年   9篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
11.
In this study antigen-independent factor in the pathogenesis of chronic rejection of organ transplants was examined.Kidney isografts and allografts were transplanted orthotopically into bilaterally nephroectomized rat recipients and studied functionaaly,morphologically and immunohistologically,at serial intervals up to 52 weeks after transplantation.Allograft recipients developed progressive proteinuria after 12 weeks,with gradual renal failure ultimately leading to death.At the same time,morphological changes,including progressive arteriosclerosis and glomerulosclerosis ,tubular atrophy and interstitial fibrosis,developed.Immunohistologically,macrophages infiltrated glomeruli during this period and cytokines became unregulated.Our results showed that antigen-independent functional and morphological changes occurred in long-tern kidney isografts and mimicked those appearing much earlier in allografts that reject chronically.Initial injury and extent of functioning renal mass is suggested to be important factor for such late changes.  相似文献   
12.
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   
13.
为了解幼儿的肝功能和HBsAg携带情况,我们于1991年肝炎发病高峰季节对我县四所幼儿园共824名幼儿进行了ALT、TTT、ZnTT、HBsAg检测。结果ALT、TTT均升高1例,有体征;ALT单项升高6例,无症状;HBsAg阳性58例,其中9例ALT升高,4例TTT升高。幼儿园是幼儿集中的地方、同吃、同住、接触密切,对HBsAg阴性者接种乙肝疫苗,对ALT升高者不能忽视以免发生肝炎流行。  相似文献   
14.
联合应用血康口服液和他莫昔芬治疗成人免疫性血小板减少性紫癜(ITP)20例。疗程超过2月。15例患者的血小板(BPC)计数明显上升,有效率为75%(15/20),对于激素治疗无效者,仍有良效。对月经过多者和不适合应用激素者尤为适应。两药合用无明显副作用。治疗起效时间较快,平均13天。疗效持续时间较长,长者已达一年以上。  相似文献   
15.
PURPOSE: To describe the outbreak of severe acute respiratory syndrome (SARS) in Toronto, its impact on anesthesia practice and the infection control guidelines adopted to manage patients in the operating room (OR) and to provide emergency intubation outside the OR. Clinical features: The SARS outbreak in Toronto was the result of a single index patient. The causative virus, SARS-CoV, is moderately contagious, and is spread by droplets and contact. The virus gains access to host through the mucosa of the respiratory tract and the eyes. It can affect both healthy and compromised patients. The use of several precautionary measures such as goggles, gloves, gowns and facemasks and the application of various infection control strategies designed to minimize the spread of the virus are discussed. CONCLUSION: In containing the spread of SARS, vigilance and strict infection control are important. This results in the rediscovery of standards of infection control measures in daily anesthesia practice.  相似文献   
16.
回顾医学美学与美容医学形成独立的学科系统的十多年来的发展历程,认为这个新兴学科在“整体学科”方面还存在一些学术问题有待人们进一步探讨。并认为,所谓“整体学科研究”是遵循该学科发展的内在规律所进行的各项研究的总和,是该学科发展的灵魂。学者们的任务在于:通过“整体学科研究”寻求其学科内在规律,经一代代同道有志者坚持不懈的努力,达到学科完善的目的。  相似文献   
17.
18.
19.
A genome-wide screen was conducted using a large white sample to identify QTLs for FNCS geometry. We found significant linkage of FNCS parameters to 20q12 and Xq25, plus significant epistatic interactions and sex-specific QTLs influencing FNCS geometry variation. INTRODUCTION: Bone geometry, a highly heritable trait, is a critical component of bone strength that significantly determines osteoporotic fracture risk. Specifically, femoral neck cross-sectional (FNCS) geometry is significantly associated with hip fracture risk as well as genetic factors. However, genetic research in this respect is still in its infancy. MATERIALS AND METHODS: To identify the underlying genomic regions influencing FNCS variables, we performed a remarkably large-scale whole genome linkage scan involving 3998 individuals from 434 pedigrees for four FNCS geometry parameters, namely buckling ratio (BR), cross-sectional area (CSA), cortical thickness (CT), and section modulus (Z). The major statistical approach adopted is the variance component method implemented in SOLAR. RESULTS: Significant linkage evidence (threshold LOD = 3.72 after correction for tests of multiple phenotypes) was found in the regions of 20q12 and Xq25 for CT (LOD = 4.28 and 3.90, respectively). We also identified eight suggestive linkage signals (threshold LOD = 2.31 after correction for multiple tests) for the respective geometry traits. The above findings were supported by principal component linkage analysis. Of them, 20q12 was of particular interest because it was linked to multiple FNCS geometry traits and significantly interacted with five other genomic loci to influence CSA variation. The effects of 20q12 on FNCS geometry were present in both male and female subgroups. Subgroup analysis also revealed the presence of sex-specific quantitative trait loci (QTLs) for FNCS traits in the regions such as 2p14, 3q26, 7q21 and 15q21. CONCLUSIONS: Our findings laid a foundation for further replication and fine-mapping studies as well as for positional and functional candidate gene studies, aiming at eventually finding the causal genetic variants and hidden mechanisms concerning FNCS geometry variation and the associated hip fractures.  相似文献   
20.
本文采用改良的邻革之酚自氧化法,对51例无遗传性疾病早孕妇女绒毛细胞进行了SOD活力测定。其比活力为426.2±48.4u/mg蛋白(x±SD),测定值范围为217.2~589.1u/mg蛋白,P95>915.0u/mg蛋白。  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