全文获取类型
收费全文 | 14092篇 |
免费 | 923篇 |
国内免费 | 38篇 |
专业分类
耳鼻咽喉 | 229篇 |
儿科学 | 506篇 |
妇产科学 | 368篇 |
基础医学 | 2066篇 |
口腔科学 | 242篇 |
临床医学 | 1660篇 |
内科学 | 2532篇 |
皮肤病学 | 342篇 |
神经病学 | 1701篇 |
特种医学 | 319篇 |
外科学 | 1392篇 |
综合类 | 69篇 |
一般理论 | 13篇 |
预防医学 | 1122篇 |
眼科学 | 239篇 |
药学 | 905篇 |
中国医学 | 18篇 |
肿瘤学 | 1330篇 |
出版年
2023年 | 103篇 |
2022年 | 183篇 |
2021年 | 308篇 |
2020年 | 250篇 |
2019年 | 340篇 |
2018年 | 370篇 |
2017年 | 313篇 |
2016年 | 377篇 |
2015年 | 414篇 |
2014年 | 515篇 |
2013年 | 729篇 |
2012年 | 1090篇 |
2011年 | 1044篇 |
2010年 | 640篇 |
2009年 | 562篇 |
2008年 | 878篇 |
2007年 | 917篇 |
2006年 | 898篇 |
2005年 | 853篇 |
2004年 | 795篇 |
2003年 | 722篇 |
2002年 | 685篇 |
2001年 | 108篇 |
2000年 | 71篇 |
1999年 | 126篇 |
1998年 | 167篇 |
1997年 | 137篇 |
1996年 | 104篇 |
1995年 | 111篇 |
1994年 | 73篇 |
1993年 | 79篇 |
1992年 | 64篇 |
1991年 | 75篇 |
1990年 | 63篇 |
1989年 | 46篇 |
1988年 | 49篇 |
1987年 | 33篇 |
1986年 | 46篇 |
1985年 | 42篇 |
1984年 | 41篇 |
1983年 | 46篇 |
1982年 | 46篇 |
1981年 | 28篇 |
1980年 | 38篇 |
1979年 | 38篇 |
1978年 | 24篇 |
1977年 | 28篇 |
1976年 | 34篇 |
1974年 | 24篇 |
1972年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
82.
83.
84.
We report a case of isolated voluminous fetal ascites discovered during a routine fetal ultrasound at 22 weeks' gestation. Analysis of the fluid showed it to be chyliform and ruled out other causes of fetal ascites. Regular bimonthly ultrasound scans monitored its progressive diminution and then its disappearance. Examination showed the child to be normal at birth. Though the literature indicates that prognosis is usually favorable for infants with isolated fetal chylous ascites, spontaneous regression during pregnancy is an uncommon finding. 相似文献
85.
86.
87.
Ohne Zusammenfassung 相似文献
88.
Frank Vandenbussche Elisabeth Mathijs Wannes Philips Meruyert Saduakassova Ilse De Leeuw Akhmetzhan Sultanov Andy Haegeman Kris De Clercq 《Viruses》2022,14(7)
From 2017 to 2019, several vaccine-like recombinant strains of lumpy skin disease virus (LSDV) were discovered in Kazakhstan and neighbouring regions of Russia and China. Shortly before their emergence, the authorities in Kazakhstan launched a mass vaccination campaign with the Neethling-based Lumpivax vaccine. Since none of the other countries in the affected region had used a homologous LSDV vaccine, it was soon suspected that the Lumpivax vaccine was the cause of these unusual LSDV strains. In this study, we performed a genome-wide molecular analysis to investigate the composition of two Lumpivax vaccine batches and to establish a possible link between the vaccine and the recent outbreaks. Although labelled as a pure Neethling-based LSDV vaccine, the Lumpivax vaccine appears to be a complex mixture of multiple CaPVs. Using an iterative enrichment/assembly strategy, we obtained the complete genomes of a Neethling-like LSDV vaccine strain, a KSGP-like LSDV vaccine strain and a Sudan-like GTPV strain. The same analysis also revealed the presence of several recombinant LSDV strains that were (almost) identical to the recently described vaccine-like LSDV strains. Based on their InDel/SNP signatures, the vaccine-like recombinant strains can be divided into four groups. Each group has a distinct breakpoint pattern resulting from multiple recombination events, with the number of genetic exchanges ranging from 126 to 146. The enormous divergence of the recombinant strains suggests that they arose during seed production. The recent emergence of vaccine-like LSDV strains in large parts of Asia is, therefore, most likely the result of a spillover from animals vaccinated with the Lumpivax vaccine. 相似文献
89.
Eric Sundstrom John W. Lounsbury C. Richard Schuller James R. Fowler Thomas J. Mattingly 《Journal of community psychology》1977,5(3):199-208
This study examined the relationship between attitudes toward a proposed nuclear power generating facility and the outcomes expected to accompany it. In a survey of 350 residents of a small rural community, approximately 2/3 expressed favorable attitudes toward the proposed nuclear plant. A principal components factor analysis of the anticipated likelihoods of outcomes of the plant revealed five factors: hazards, economic growth, lower costs, social disruption, and community visibility. Using these factors as predictors, a simple multiple regression equation accounted for 52% of the variation in attitudes toward the plant. The strongest predictor was the perceived likelihood of hazards. These findings are discussed in terms of the relationship between attitudes and expectations, and in relation to decisions regarding public policy. 相似文献
90.