全文获取类型
收费全文 | 84072篇 |
免费 | 7980篇 |
国内免费 | 967篇 |
专业分类
耳鼻咽喉 | 404篇 |
儿科学 | 2646篇 |
妇产科学 | 1733篇 |
基础医学 | 5797篇 |
口腔科学 | 1743篇 |
临床医学 | 7830篇 |
内科学 | 15707篇 |
皮肤病学 | 1071篇 |
神经病学 | 4157篇 |
特种医学 | 1942篇 |
外国民族医学 | 1篇 |
外科学 | 9450篇 |
综合类 | 13412篇 |
现状与发展 | 8篇 |
一般理论 | 18篇 |
预防医学 | 15784篇 |
眼科学 | 934篇 |
药学 | 4887篇 |
64篇 | |
中国医学 | 1125篇 |
肿瘤学 | 4306篇 |
出版年
2024年 | 245篇 |
2023年 | 1666篇 |
2022年 | 2841篇 |
2021年 | 4040篇 |
2020年 | 3632篇 |
2019年 | 5440篇 |
2018年 | 5036篇 |
2017年 | 3721篇 |
2016年 | 2903篇 |
2015年 | 2768篇 |
2014年 | 5626篇 |
2013年 | 6084篇 |
2012年 | 4610篇 |
2011年 | 4870篇 |
2010年 | 3867篇 |
2009年 | 3537篇 |
2008年 | 3423篇 |
2007年 | 3015篇 |
2006年 | 2750篇 |
2005年 | 2152篇 |
2004年 | 1694篇 |
2003年 | 1395篇 |
2002年 | 1130篇 |
2001年 | 1008篇 |
2000年 | 798篇 |
1999年 | 668篇 |
1998年 | 573篇 |
1997年 | 506篇 |
1996年 | 380篇 |
1995年 | 378篇 |
1994年 | 309篇 |
1993年 | 262篇 |
1992年 | 182篇 |
1991年 | 162篇 |
1990年 | 125篇 |
1989年 | 115篇 |
1988年 | 102篇 |
1985年 | 927篇 |
1984年 | 1447篇 |
1983年 | 1135篇 |
1982年 | 1138篇 |
1981年 | 1128篇 |
1980年 | 978篇 |
1979年 | 858篇 |
1978年 | 666篇 |
1977年 | 473篇 |
1976年 | 636篇 |
1975年 | 553篇 |
1974年 | 473篇 |
1973年 | 430篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Nicola Flaum Emma J. Crosbie Richard J. Edmondson Miriam J. Smith Dafydd G. Evans 《Clinical genetics》2020,97(1):54-63
Ovarian cancer is the fourth most common cause of cancer-related death in women in the developed world, and one of the most heritable cancers. One of the most significant risk factors for epithelial ovarian cancer (EOC) is a family history of breast and/or ovarian cancer. Combined risk factors can be used in models to stratify risk of EOC, and aid in decisions regarding risk-reduction strategies. Germline pathogenic variants in EOC susceptibility genes including those involved in homologous recombination and mismatch repair pathways are present in approximately 22% to 25% of EOC. These genes are associated with an estimated lifetime risk of EOC of 13% to 60% for BRCA1 variants and 10% to 25% for BRCA2 variants, with lower risks associated with remaining genes. Genome-wide association studies have identified single nucleotide polymorphisms (SNPs) thought to explain an additional 6.4% of the familial risk of ovarian cancer, with 34 susceptibility loci identified to date. However, an unknown proportion of the genetic component of EOC risk remains unexplained. This review comprises an overview of individual genes and SNPs suspected to contribute to risk of EOC, and discusses use of a polygenic risk score to predict individual cancer risk more accurately. 相似文献
52.
53.
对于医疗设备来说,其临床医疗中有十分重要的作用,而且医疗设备的实际运行效率也与医院的经济效益有直接的关系,但是在大部分医院中仍然采用传统的医疗设备养护方式,导致医疗设备的维护缺乏科学性,从而增加了医疗设备故障的发生率,并且也影响了实际应用的效果,严重的情况下甚至会发生医疗事故。基于此,该文主要对医疗设备预防性保养的重要性与方法进行分析,希望能够使医疗设备的性能得到最优化的体现,使其能够更好地为医疗服务的开展提供支持。 相似文献
54.
55.
Elisa M. González 《Medical history》2015,59(2):177-198
Between the 1930s and 1960s Puerto Rico was transformed from a marginal United States territory into an industrialised ‘showcase of development’. This article investigates the organisation of milk station programmes on the island during this crucial period and how these reflected the circulation of child welfare knowledge, nutrition expertise and public health practices. During the Depression, these perspectives fostered a recast of the eugenic regeneration ideologies motivating medical assessments of and sanitary interventions with Puerto Rico’s rural poor since the nineteenth century. Innovations in nutrition knowledge and an emerging rural hygiene movement highlighted the negative health effects of the island’s monocrops economy. In this context, the nourishment of children’s bodies assumed symbolic and instrumental significance for the reconfiguration of colonial and developmental models promoted by the new Popular Democratic Party (PPD). The experience of public health professionals in relief work during the 1930s contributed to the articulation of food and nutrition as key elements of this party’s populist discourse. Programmes like milk stations became part of strategies to rear and manage the labour force needed in the industrial development model promoted by the PPD. From the perspective of poor Puerto Ricans, however, they were part of the materialisation of its promise of social justice for the poorer classes. 相似文献
56.
Jessica K. Perrotte Michael R. Baumann Raymond T. Garza Willie J. Hale 《Ethnicity & health》2020,25(1):47-64
ABSTRACTObjectives: The present study investigated the relationships of enculturation and depressive symptoms with health risk behavior engagement in Mexican-American college students and examined how these relationships differed by gender. Previous research has noted consistent gender differences in health risk behavior (e.g. alcohol use, substance use, and risky sexual behavior) among Latina/os, and emphasized the role of U.S. acculturation in this difference. Research examining the role of heritage cultural retention (i.e. enculturation), and including the added influence of mental health variables, such as depressive symptoms, is currently lacking. This study sought to address this gap.Design: A large sample (N?=?677) of Mexican-American college students from four universities (located in New York, California, Florida, and Texas) completed an online questionnaire assessing health risk behaviors and corresponding variables.Results: We found that males who endorsed more behavioral enculturation and depressive symptoms were more likely to engage in health risk behavior than all others in the sample. Contrary to previous literature, no relationship was found between behavioral enculturation and health risk behavior in females.Conclusion: The current study found behavioral enculturation to be associated with depressive symptoms, and in turn with health risk behaviors among the males in our sample. Additional research will be needed to identify the mechanism underlying the relationship between enculturation and depressive symptoms as well as between depressive symptoms and risky behavior. 相似文献
57.
58.
59.
Danail Hristozov Alex Zabeo Keld Alstrup Jensen Stefania Gottardo Panagiotis Isigonis Laura Maccalman 《Nanotoxicology》2016,10(9):1215-1228
Several tools to facilitate the risk assessment and management of manufactured nanomaterials (MN) have been developed. Most of them require input data on physicochemical properties, toxicity and scenario-specific exposure information. However, such data are yet not readily available, and tools that can handle data gaps in a structured way to ensure transparent risk analysis for industrial and regulatory decision making are needed. This paper proposes such a quantitative risk prioritisation tool, based on a multi-criteria decision analysis algorithm, which combines advanced exposure and dose-response modelling to calculate margins of exposure (MoE) for a number of MN in order to rank their occupational risks. We demonstrated the tool in a number of workplace exposure scenarios (ES) involving the production and handling of nanoscale titanium dioxide, zinc oxide (ZnO), silver and multi-walled carbon nanotubes. The results of this application demonstrated that bag/bin filling, manual un/loading and dumping of large amounts of dry powders led to high emissions, which resulted in high risk associated with these ES. The ZnO MN revealed considerable hazard potential in vivo, which significantly influenced the risk prioritisation results. In order to study how variations in the input data affect our results, we performed probabilistic Monte Carlo sensitivity/uncertainty analysis, which demonstrated that the performance of the proposed model is stable against changes in the exposure and hazard input variables. 相似文献
60.