全文获取类型
收费全文 | 6068篇 |
免费 | 401篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 196篇 |
妇产科学 | 139篇 |
基础医学 | 1056篇 |
口腔科学 | 67篇 |
临床医学 | 684篇 |
内科学 | 1126篇 |
皮肤病学 | 187篇 |
神经病学 | 556篇 |
特种医学 | 129篇 |
外科学 | 497篇 |
综合类 | 78篇 |
一般理论 | 4篇 |
预防医学 | 778篇 |
眼科学 | 170篇 |
药学 | 313篇 |
中国医学 | 17篇 |
肿瘤学 | 460篇 |
出版年
2023年 | 48篇 |
2022年 | 55篇 |
2021年 | 155篇 |
2020年 | 86篇 |
2019年 | 118篇 |
2018年 | 154篇 |
2017年 | 122篇 |
2016年 | 147篇 |
2015年 | 160篇 |
2014年 | 217篇 |
2013年 | 323篇 |
2012年 | 402篇 |
2011年 | 487篇 |
2010年 | 261篇 |
2009年 | 244篇 |
2008年 | 423篇 |
2007年 | 370篇 |
2006年 | 396篇 |
2005年 | 428篇 |
2004年 | 349篇 |
2003年 | 340篇 |
2002年 | 299篇 |
2001年 | 58篇 |
2000年 | 49篇 |
1999年 | 44篇 |
1998年 | 60篇 |
1997年 | 51篇 |
1996年 | 44篇 |
1995年 | 41篇 |
1994年 | 39篇 |
1993年 | 46篇 |
1992年 | 32篇 |
1991年 | 25篇 |
1990年 | 25篇 |
1989年 | 18篇 |
1988年 | 24篇 |
1987年 | 12篇 |
1986年 | 14篇 |
1985年 | 20篇 |
1984年 | 23篇 |
1983年 | 19篇 |
1982年 | 23篇 |
1981年 | 13篇 |
1980年 | 15篇 |
1979年 | 12篇 |
1978年 | 12篇 |
1976年 | 15篇 |
1975年 | 23篇 |
1974年 | 14篇 |
1973年 | 17篇 |
排序方式: 共有6485条查询结果,搜索用时 31 毫秒
991.
Aarø LE Breivik K Klepp KI Kaaya S Onya HE Wubs A Helleve A Flisher AJ 《Health education research》2011,26(2):212-224
A 14-item human immunodeficiency virus/acquired immunodeficiency syndrome knowledge scale was used among school students in 80 schools in 3 sites in Sub-Saharan Africa (Cape Town and Mankweng, South Africa, and Dar es Salaam, Tanzania). For each item, an incorrect or don't know response was coded as 0 and correct response as 1. Exploratory factor analyses based on polychoric correlations showed two separate factors for all sites. Two-parameter item response theory (IRT) analysis (bifactorial multiple indicators multiple causes confirmatory factor analysis models) consistently showed a general first factor and a second 'method' factor. One single global latent variable seemed to sufficiently well capture most of the systematic variation in knowledge. Some items did not discriminate well between levels of the underlying knowledge latent variable and information values were highest for low levels of knowledge. The scale might be improved by adding items, in particular items that are more difficult to answer. Some differential item functioning effects related to site and socioeconomic status were identified. Scores on the latent knowledge variable were particularly low among females in Dar es Salaam and Mankweng, and were negatively associated with socioeconomic status. This study illustrates advantages of using IRT analysis instead of more conventional approaches to examining psychometric properties of knowledge scales. 相似文献
992.
993.
Jeffrey I. Campbell Angella Musiimenta Bridget Burns Sylvia Natukunda Nicholas Musinguzi Jessica E. Haberer 《AIDS care》2019,31(6):761-766
Novel monitoring technologies in HIV research, such as electronic adherence monitors (EAMs), have changed the nature of researcher-participant interactions. Yet little is known about how EAMs and the resulting interaction between researchers and participants affect research participation and the data gathered. We interviewed participants and research assistants (RAs) in an observational cohort study involving EAMs for HIV antiretroviral therapy (ART) in Uganda. We qualitatively explored interviewees’ views about ethical issues surrounding EAMs and assessed data with conventional and directed content analysis. Participants valued their relationships with RAs and were preoccupied with RAs’ perceptions of them. Participants were pleased when the EAM revealed regular adherence, and annoyed when it revealed non-adherence that contradicted self-reported pill-taking behavior. For many, the desire to maintain a good impression incentivized adherence. But some sought to creatively conceal non-adherence, or refused to use the EAM to avoid revealing non-adherence to RAs. These findings show that participants’ perceptions of the study staff's perceptions of them affected the experience of being monitored, study participation, and ultimately the data gathered in the study. Investigators in monitoring-based research should be aware that social interactions between participants and study staff could affect both the practical and ethical conduct of that research. 相似文献
994.
995.
996.
Lindy M. Kregting Sylvia Kaljouw Lucie de Jonge Erik E. L. Jansen Elisabeth F. P. Peterse Eveline A. M. Heijnsdijk Nicolien T. van Ravesteyn Iris Lansdorp-Vogelaar Inge M. C. M. de Kok 《British journal of cancer》2021,124(9):1516
Background Many breast, cervical, and colorectal cancer screening programmes were disrupted due to the COVID-19 pandemic. This study aimed to estimate the effects of five restart strategies after the disruption on required screening capacity and cancer burden.Methods Microsimulation models simulated five restart strategies for breast, cervical, and colorectal cancer screening. The models estimated required screening capacity, cancer incidence, and cancer-specific mortality after a disruption of 6 months. The restart strategies varied in whether screens were caught up or not and, if so, immediately or delayed, and whether the upper age limit was increased.Results The disruption in screening programmes without catch-up of missed screens led to an increase of 2.0, 0.3, and 2.5 cancer deaths per 100 000 individuals in 10 years in breast, cervical, and colorectal cancer, respectively. Immediately catching-up missed screens minimised the impact of the disruption but required a surge in screening capacity. Delaying screening, but still offering all screening rounds gave the best balance between required capacity, incidence, and mortality.Conclusions Strategies with the smallest loss in health effects were also the most burdensome for the screening organisations. Which strategy is preferred depends on the organisation and available capacity in a country.Subject terms: Health policy, Population screening, Cancer screening, Cancer screening 相似文献
997.
998.
Epidermodysplasia Verruciformis in Lipoid Proteinosis: Case Report and Discussion of Pathophysiology
下载免费PDF全文
![点击此处可从《Pediatric dermatology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Catherine O'Blenes M.D. Ph.D. Sylvia Pasternak M.D. Andrew Issekutz M.D. Jane Gillis M.D. M.Sc. Dhiman Chowdhury M.B.B.S. Laura Finlayson M.D. 《Pediatric dermatology》2015,32(1):118-121
Lipoid proteinosis (LP) is a rare autosomal recessive genodermatosis caused by mutations in extracellular matrix protein 1 (ECM1) that involves deposition of basement membrane–like material in the skin and other organs. Epidermodysplasia verruciformis (EV) is also a rare autosomal recessive genodermatosis involving susceptibility to human papillomavirus (HPV) infections and squamous cell carcinoma, caused in most cases by homozygous mutations in EVER1 or EVER2. We describe a case of EV in a patient with LP and discuss the pathophysiology. A 3‐year‐old Lebanese girl presented with hoarseness, beaded papules along the eyelid margins, waxy papules and plaques on her head and neck, and lichenoid verrucous papules on the forearms and hands. Histopathology of the waxy papules exhibited deposition of periodic acid Schiff–positive basement membrane–like material in the superficial dermis, characteristic of LP. The verruca plana–like lesions exhibited acanthosis and enlarged keratinocytes with pale blue‐grey cytoplasm and a perinuclear halo, consistent with verrucae and EV. Polymerase chain reaction amplification and sequencing of ECM1, EVER1, and EVER2 demonstrated a homozygous point mutation, c.389C>T (p.Thr130Met), in exon 6 of ECM1 and a heterozygous point mutation, c.917 A>T (p.Asn306Ile), in exon 8 in EVER2, known to cause EV in homozygous patients. The homozygous point mutation c.389C>T in ECM1 may be a novel mutation causing LP. Verruca plana–like lesions seen in LP appear to represent a form of acquired EV. In this patient, a heterozygous mutation in EVER2 at c.917 A>T may also have conferred susceptibility to HPV infection. 相似文献
999.
1000.