全文获取类型
收费全文 | 10582篇 |
免费 | 847篇 |
国内免费 | 61篇 |
专业分类
耳鼻咽喉 | 113篇 |
儿科学 | 386篇 |
妇产科学 | 213篇 |
基础医学 | 1469篇 |
口腔科学 | 198篇 |
临床医学 | 951篇 |
内科学 | 2289篇 |
皮肤病学 | 202篇 |
神经病学 | 991篇 |
特种医学 | 369篇 |
外科学 | 1764篇 |
综合类 | 122篇 |
一般理论 | 4篇 |
预防医学 | 761篇 |
眼科学 | 142篇 |
药学 | 636篇 |
中国医学 | 33篇 |
肿瘤学 | 847篇 |
出版年
2023年 | 62篇 |
2022年 | 119篇 |
2021年 | 254篇 |
2020年 | 160篇 |
2019年 | 282篇 |
2018年 | 335篇 |
2017年 | 256篇 |
2016年 | 236篇 |
2015年 | 268篇 |
2014年 | 378篇 |
2013年 | 464篇 |
2012年 | 628篇 |
2011年 | 650篇 |
2010年 | 415篇 |
2009年 | 354篇 |
2008年 | 471篇 |
2007年 | 556篇 |
2006年 | 497篇 |
2005年 | 455篇 |
2004年 | 411篇 |
2003年 | 365篇 |
2002年 | 360篇 |
2001年 | 330篇 |
2000年 | 332篇 |
1999年 | 322篇 |
1998年 | 128篇 |
1997年 | 106篇 |
1996年 | 100篇 |
1995年 | 101篇 |
1994年 | 107篇 |
1993年 | 70篇 |
1992年 | 198篇 |
1991年 | 201篇 |
1990年 | 175篇 |
1989年 | 170篇 |
1988年 | 128篇 |
1987年 | 143篇 |
1986年 | 131篇 |
1985年 | 97篇 |
1984年 | 77篇 |
1983年 | 51篇 |
1982年 | 36篇 |
1981年 | 44篇 |
1979年 | 58篇 |
1978年 | 48篇 |
1977年 | 38篇 |
1976年 | 36篇 |
1975年 | 32篇 |
1974年 | 36篇 |
1973年 | 36篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
Oral Diseases (2010) 16 , 160–166 Objective: The aim of this comparative study was to analyze cytopathologically and chemico‐physically the mucosa surrounding oral piercing to correlate results with adverse tissue signs. Materials and methods: The tongue superficial mucosa of 15 young subjects (control group) and the superficial mucosa surrounding oral piercing of 15 young subjects (test group, TG) were smeared on slides, Papanicolaou stained and analyzed under the optical microscope. Some smears were prepared for (back‐scattered) scanning electron microscope (SEM) and X‐ray microanalysis to study piercing fragments. Results: Smears of TG displayed a variable extent of bacterial cytolysis of epithelial cells, fungi, hyperkeratosis, parakeratosis, granulocyte infiltration, calcium formations and bacterial flora; the four last statistically significant (P < 0.05). Foreign bodies surrounded by keratinocytes were detected under both light and SEM. X‐ray microanalyses highlighted piercing alloy aggression, ion release and an inverse gradient of ion concentration inside keratinocytes. Conclusions: The pathological findings in smears correlated with adverse effects of oral piercing. Ion release may be related to direct toxic effects and belated reactions because of metal sensitization. A strict regulation of piercing is warranted. 相似文献
994.
There is currently great demand among adult patients for aesthetic solutions. In the great majority of cases, patients present with serious oral problems in their mouths, such as over-crowding, ageneses, edentulous spaces from old extractions, periodontal problems, etc. In the face of all these problems we need interdisciplinary strategies that will help us carry out the complex and imaginative treatments that these cases require. In this article we are going to describe the interdisciplinary treatment that we provided to two adult patients. 1--On a 25 year old male patient with significant upper maxillary crowding with transversal constriction and absence of the upper right lateral incisor; through correction of the over-crowding, the maxillary constriction and rehabilitation with an implant-supported fixed prosthesis in the edentulous space, we will treat and correct this case. 2--A 29 year old male patient with agenesis of the superior canines and edentulous gap in the inferior dental arch. 相似文献
995.
996.
Lederman MM Alter G Daskalakis DC Rodriguez B Sieg SF Hardy G Cho M Anthony D Harding C Weinberg A Silverman RH Douek DC Margolis L Goldstein DB Carrington M Goedert JJ 《The Journal of infectious diseases》2010,202(Z3):S333-S338
Both clinical experience and a growing medical literature indicate that some persons who have been exposed to human immunodeficiency virus (HIV) infection remain uninfected. Although in some instances this may represent good fortune, cohorts of uninfected persons have been reported who are considered at high risk for infection. In these cohorts a variety of characteristics have been proposed as mediating protection, but to date only the 32–base pair deletion in the chemokine (C‐C motif) receptor 5 gene, which results in complete failure of cell surface expression of this coreceptor, has been associated with high‐level protection from HIV infection. With this in mind, there are probably many other factors that may individually or in combination provide some level of protection from acquisition of HIV infection. Because some of these factors are probably incompletely protective or inconsistently active, identifying them with confidence will be difficult. Nonetheless, clarifying the determinants of protection against HIV infection is a high priority that will require careful selection of high‐risk uninfected cohorts, who should undergo targeted studies of plausible mediators and broad screening for unexpected determinants of protection. 相似文献
997.
Elzbieta Kula-Eversole Emi Nagoshi Yuhua Shang Joseph Rodriguez Ravi Allada Michael Rosbash 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(30):13497-13502
To compare circadian gene expression within highly discrete neuronal populations, we separately purified and characterized two adjacent but distinct groups of Drosophila adult circadian neurons: the 8 small and 10 large PDF-expressing ventral lateral neurons (s-LNvs and l-LNvs, respectively). The s-LNvs are the principal circadian pacemaker cells, whereas recent evidence indicates that the l-LNvs are involved in sleep and light-mediated arousal. Although half of the l-LNv–enriched mRNA population, including core clock mRNAs, is shared between the l-LNvs and s-LNvs, the other half is l-LNv– and s-LNv–specific. The distribution of four specific mRNAs is consistent with prior characterization of the four encoded proteins, and therefore indicates successful purification of the two neuronal types. Moreover, an octopamine receptor mRNA is selectively enriched in l-LNvs, and only these neurons respond to in vitro application of octopamine. Dissection and purification of l-LNvs from flies collected at different times indicate that these neurons contain cycling clock mRNAs with higher circadian amplitudes as well as at least a 10-fold higher fraction of oscillating mRNAs than all previous analyses of head RNA. Many of these cycling l-LNv mRNAs are well expressed but do not cycle or cycle much less well elsewhere in heads. The results suggest that RNA cycling is much more prominent in circadian neurons than elsewhere in heads and may be particularly important for the functioning of these neurons. 相似文献
998.
999.
1000.