全文获取类型
收费全文 | 44567篇 |
免费 | 3304篇 |
国内免费 | 1826篇 |
专业分类
耳鼻咽喉 | 315篇 |
儿科学 | 595篇 |
妇产科学 | 976篇 |
基础医学 | 10070篇 |
口腔科学 | 907篇 |
临床医学 | 2995篇 |
内科学 | 6653篇 |
皮肤病学 | 635篇 |
神经病学 | 1953篇 |
特种医学 | 1844篇 |
外国民族医学 | 5篇 |
外科学 | 2145篇 |
综合类 | 5571篇 |
现状与发展 | 5篇 |
预防医学 | 3295篇 |
眼科学 | 360篇 |
药学 | 4696篇 |
3篇 | |
中国医学 | 1265篇 |
肿瘤学 | 5409篇 |
出版年
2024年 | 74篇 |
2023年 | 574篇 |
2022年 | 1017篇 |
2021年 | 1386篇 |
2020年 | 1270篇 |
2019年 | 1221篇 |
2018年 | 1123篇 |
2017年 | 1240篇 |
2016年 | 1420篇 |
2015年 | 1623篇 |
2014年 | 2333篇 |
2013年 | 3024篇 |
2012年 | 2179篇 |
2011年 | 2489篇 |
2010年 | 2070篇 |
2009年 | 2171篇 |
2008年 | 2165篇 |
2007年 | 2217篇 |
2006年 | 2132篇 |
2005年 | 2043篇 |
2004年 | 1837篇 |
2003年 | 1657篇 |
2002年 | 1410篇 |
2001年 | 1315篇 |
2000年 | 1122篇 |
1999年 | 912篇 |
1998年 | 880篇 |
1997年 | 799篇 |
1996年 | 753篇 |
1995年 | 691篇 |
1994年 | 715篇 |
1993年 | 501篇 |
1992年 | 526篇 |
1991年 | 393篇 |
1990年 | 368篇 |
1989年 | 306篇 |
1988年 | 273篇 |
1987年 | 177篇 |
1986年 | 178篇 |
1985年 | 235篇 |
1984年 | 198篇 |
1983年 | 82篇 |
1982年 | 115篇 |
1981年 | 112篇 |
1980年 | 110篇 |
1979年 | 74篇 |
1978年 | 73篇 |
1977年 | 37篇 |
1976年 | 37篇 |
1975年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 20 毫秒
1.
《International journal of oral and maxillofacial surgery》2022,51(3):332-337
The purpose of this study was to investigate the association between habitual snoring (HS), middle ear disease (MED), and speech problems in children with cleft palate. This cross-sectional study included children aged 2.0–7.9 years with non-syndromic cleft palate anomalies. Parents completed the Pediatric Sleep Questionnaire and a questionnaire about MED. Audiograms and speech assessment were also conducted. Ninety-five children were enrolled; 15.2% of families reported HS, 97.6% MED, and 17.1% speech problems. HS (37.5% vs 10.3%, P = 0.007) and early episodes of MED (92.3% vs 58.2%, P = 0.021) were more likely to be reported for children with isolated cleft palate when compared to those with cleft lip and palate. Children with cleft lip and palate had a higher frequency of MED with effusion compared to those with Robin sequence (86.4% vs 57.1%, P = 0.049). The odds ratio for HS in children with ≥1 episode of MED in the last year was 7.37 (95% confidence interval 1.55–35.15, P = 0.012). There was a trend for children with speech problems reported by parents to have HS (30.8% vs 11.5%, P= 0.076). Anatomical factors play a role in the frequency of upper airway symptoms in children with cleft palate. A recent history of at least one episode of MED was associated with an increased frequency of HS. 相似文献
2.
3.
《Cancer cell》2021,39(9):1214-1226.e10
- Download : Download high-res image (204KB)
- Download : Download full-size image
4.
《Molecular therapy》2022,30(8):2856-2867
- Download : Download high-res image (173KB)
- Download : Download full-size image
5.
Lipid nanoparticles (LNPs) are becoming popular as a means of delivering therapeutics, including those based on nucleic acids and mRNA. The mRNA-based coronavirus disease 2019 vaccines are perfect examples to highlight the role played by drug delivery systems in advancing human health. The fundamentals of LNPs for the delivery of nucleic acid- and mRNA-based therapeutics, are well established. Thus, future research on LNPs will focus on addressing the following: expanding the scope of drug delivery to different constituents of the human body, expanding the number of diseases that can be targeted, and studying the change in the pharmacokinetics of LNPs under physiological and pathological conditions. This review article provides an overview of recent advances aimed at expanding the application of LNPs, focusing on the pharmacokinetics and advantages of LNPs. In addition, analytical techniques, library construction and screening, rational design, active targeting, and applicability to gene editing therapy have also been discussed. 相似文献
6.
应用拷贝数变异测序(copy number variation sequencing,CNV-seq)技术鉴别来源不明的胎儿标记染色体,明确其遗传物质的来源,并探讨此技术在产前诊断中的应用价值。讨论Pallister-Killian综合征(Pallister-Killian syndrome,PKS)的临床特征及遗传学特点,提高对此类罕见染色体疾病的认识。该病例因在妊娠中期超声发现胎儿异常而行羊水穿刺进行CNV-Seq检测,同时分析胎儿和父母的核型。羊水CNV-Seq结果示该样本12号染色体p13.33-p11.1处检测到拷贝数为3.5、片段大小为34.70 Mb的嵌合重复区域;羊水染色体核型结果为47,XY,+i(12)(p10)[58]/46,XX[42],综合上述结果考虑为PKS。通过结合超声结果,综合应用染色体G显带核型分析和CNV-seq技术能准确确认染色体异常片段来源,在产前有效诊断PKS患者。 相似文献
7.
目的 检测分析被诊断为X连锁视网膜色素变性(XLRP)的三个中国家系内的基因突变。设计 基因研究。研究对象 三个中国XLRP家系共27位受试者(其中18人为男性)。方法 由同一医生收集家系成员的详细临床资料并进行眼部检查,采集三个家系的先证者及有条件采血者的外周静脉血,提取基因组DNA。应用PCR技术扩增RPGR和RP2基因的全部外显子和内含子交界区序列,包括RPGR基因15号外显子开放阅读框,产物直接测序进行突变分析。主要指标 临床特征及基因测序结果。结果 基因筛查证实了两个RPGR基因的新型无义突变(c.1541C>G;p.S514X 和 c.2833G>T;p.E945X) 及一个错义突变(c.607G>C;p.A203P)。基因型-表型的相关性分析表明家系3患者在接近ORF15下游位置存在突变,这种突变导致视锥细胞功能的早期丧失。ORF15无义突变的女性携带者临床表型重,呈现出部分显性遗传的特点。结论 本研究证实了三种RPGR基因的新型突变,这一结果扩展了RPGR的突变谱及表型谱。 相似文献
8.
9.
Xiaoyan Lu Isabelle R. Miousse Sandra V. Pirela Jodene K. Moore Stepan Melnyk 《Nanotoxicology》2016,10(5):629-639
Evidence continues to grow on potential environmental health hazards associated with engineered nanomaterials (ENMs). While the geno- and cytotoxic effects of ENMs have been investigated, their potential to target the epigenome remains largely unknown. The aim of this study is two-fold: 1) determining whether or not industry relevant ENMs can affect the epigenome in vivo and 2) validating a recently developed in vitro epigenetic screening platform for inhaled ENMs. Laser printer-emitted engineered nanoparticles (PEPs) released from nano-enabled toners during consumer use and copper oxide (CuO) were chosen since these particles induced significant epigenetic changes in a recent in vitro companion study. In this study, the epigenetic alterations in lung tissue, alveolar macrophages and peripheral blood from intratracheally instilled mice were evaluated. The methylation of global DNA and transposable elements (TEs), the expression of the DNA methylation machinery and TEs, in addition to general toxicological effects in the lung were assessed. CuO exhibited higher cell-damaging potential to the lung, while PEPs showed a greater ability to target the epigenome. Alterations in the methylation status of global DNA and TEs, and expression of TEs and DNA machinery in mouse lung were observed after exposure to CuO and PEPs. Additionally, epigenetic changes were detected in the peripheral blood after PEPs exposure. Altogether, CuO and PEPs can induce epigenetic alterations in a mouse experimental model, which in turn confirms that the recently developed in vitro epigenetic platform using macrophage and epithelial cell lines can be successfully utilized in the epigenetic screening of ENMs. 相似文献
10.
Rafiye Ciftciler Haluk Demiroglu Yahya Buyukasık Elifcan Aladag Salih Aksu Ibrahim C. Haznedaroglu Nilgun Sayınalp Osman Ozcebe Umit Yavuz Malkan Hakan Goker 《Clinical Lymphoma, Myeloma & Leukemia》2019,19(3):177-182