收费全文 | 1619649篇 |
免费 | 102879篇 |
国内免费 | 2264篇 |
耳鼻咽喉 | 21706篇 |
儿科学 | 54254篇 |
妇产科学 | 44307篇 |
基础医学 | 227996篇 |
口腔科学 | 41329篇 |
临床医学 | 133431篇 |
内科学 | 318903篇 |
皮肤病学 | 32269篇 |
神经病学 | 130891篇 |
特种医学 | 63721篇 |
外国民族医学 | 457篇 |
外科学 | 246881篇 |
综合类 | 29461篇 |
一般理论 | 358篇 |
预防医学 | 125845篇 |
眼科学 | 35404篇 |
药学 | 119674篇 |
1篇 | |
中国医学 | 3644篇 |
肿瘤学 | 94260篇 |
2019年 | 11283篇 |
2018年 | 37967篇 |
2017年 | 28638篇 |
2016年 | 31772篇 |
2015年 | 17005篇 |
2014年 | 21521篇 |
2013年 | 32879篇 |
2012年 | 53751篇 |
2011年 | 68745篇 |
2010年 | 45029篇 |
2009年 | 35413篇 |
2008年 | 64365篇 |
2007年 | 70095篇 |
2006年 | 50523篇 |
2005年 | 51241篇 |
2004年 | 50159篇 |
2003年 | 49016篇 |
2002年 | 46213篇 |
2001年 | 62712篇 |
2000年 | 64319篇 |
1999年 | 54523篇 |
1998年 | 14347篇 |
1997年 | 12805篇 |
1996年 | 12873篇 |
1995年 | 12860篇 |
1994年 | 12226篇 |
1992年 | 43297篇 |
1991年 | 42520篇 |
1990年 | 41989篇 |
1989年 | 40560篇 |
1988年 | 37841篇 |
1987年 | 36909篇 |
1986年 | 35176篇 |
1985年 | 33496篇 |
1984年 | 24906篇 |
1983年 | 21653篇 |
1982年 | 12863篇 |
1981年 | 11292篇 |
1979年 | 23498篇 |
1978年 | 16450篇 |
1977年 | 14240篇 |
1976年 | 13398篇 |
1975年 | 14747篇 |
1974年 | 17378篇 |
1973年 | 16784篇 |
1972年 | 15971篇 |
1971年 | 14894篇 |
1970年 | 13869篇 |
1969年 | 13413篇 |
1968年 | 12564篇 |
Vaccination prevents severe morbidity and mortality from COVID-19 in the general population. The immunogenicity and efficacy of SARS-CoV-2 vaccines in patients with antibody deficiency is poorly understood.
ObjectivesCOVID-19 in patients with antibody deficiency (COV-AD) is a multi-site UK study that aims to determine the immune response to SARS-CoV-2 infection and vaccination in patients with primary or secondary antibody deficiency, a population that suffers from severe and recurrent infection and does not respond well to vaccination.
MethodsIndividuals on immunoglobulin replacement therapy or with an IgG less than 4 g/L receiving antibiotic prophylaxis were recruited from April 2021. Serological and cellular responses were determined using ELISA, live-virus neutralisation and interferon gamma release assays. SARS-CoV-2 infection and clearance were determined by PCR from serial nasopharyngeal swabs.
ResultsA total of 5.6% (n?=?320) of the cohort reported prior SARS-CoV-2 infection, but only 0.3% remained PCR positive on study entry. Seropositivity, following two doses of SARS-CoV-2 vaccination, was 54.8% (n?=?168) compared with 100% of healthy controls (n?=?205). The magnitude of the antibody response and its neutralising capacity were both significantly reduced compared to controls. Participants vaccinated with the Pfizer/BioNTech vaccine were more likely to be seropositive (65.7% vs. 48.0%, p?=?0.03) and have higher antibody levels compared with the AstraZeneca vaccine (IgGAM ratio 3.73 vs. 2.39, p?=?0.0003). T cell responses post vaccination was demonstrable in 46.2% of participants and were associated with better antibody responses but there was no difference between the two vaccines. Eleven vaccine-breakthrough infections have occurred to date, 10 of them in recipients of the AstraZeneca vaccine.
ConclusionSARS-CoV-2 vaccines demonstrate reduced immunogenicity in patients with antibody deficiency with evidence of vaccine breakthrough infection.
相似文献