全文获取类型
收费全文 | 19643篇 |
免费 | 1475篇 |
国内免费 | 387篇 |
专业分类
耳鼻咽喉 | 105篇 |
儿科学 | 377篇 |
妇产科学 | 290篇 |
基础医学 | 2541篇 |
口腔科学 | 275篇 |
临床医学 | 2609篇 |
内科学 | 4095篇 |
皮肤病学 | 357篇 |
神经病学 | 960篇 |
特种医学 | 419篇 |
外国民族医学 | 1篇 |
外科学 | 1737篇 |
综合类 | 1392篇 |
现状与发展 | 2篇 |
一般理论 | 47篇 |
预防医学 | 2993篇 |
眼科学 | 273篇 |
药学 | 1344篇 |
18篇 | |
中国医学 | 532篇 |
肿瘤学 | 1138篇 |
出版年
2024年 | 23篇 |
2023年 | 2101篇 |
2022年 | 2827篇 |
2021年 | 6018篇 |
2020年 | 4470篇 |
2019年 | 257篇 |
2018年 | 240篇 |
2017年 | 193篇 |
2016年 | 223篇 |
2015年 | 241篇 |
2014年 | 392篇 |
2013年 | 411篇 |
2012年 | 312篇 |
2011年 | 390篇 |
2010年 | 342篇 |
2009年 | 323篇 |
2008年 | 305篇 |
2007年 | 319篇 |
2006年 | 307篇 |
2005年 | 241篇 |
2004年 | 253篇 |
2003年 | 221篇 |
2002年 | 145篇 |
2001年 | 129篇 |
2000年 | 105篇 |
1999年 | 82篇 |
1998年 | 68篇 |
1997年 | 54篇 |
1996年 | 61篇 |
1995年 | 43篇 |
1994年 | 29篇 |
1993年 | 39篇 |
1992年 | 27篇 |
1991年 | 29篇 |
1990年 | 22篇 |
1989年 | 13篇 |
1988年 | 11篇 |
1987年 | 8篇 |
1985年 | 36篇 |
1984年 | 37篇 |
1983年 | 23篇 |
1982年 | 23篇 |
1981年 | 23篇 |
1980年 | 16篇 |
1979年 | 13篇 |
1977年 | 10篇 |
1976年 | 5篇 |
1975年 | 10篇 |
1974年 | 6篇 |
1973年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
81.
《Vaccine》2022,40(33):4748-4763
This work identifies the innovations that made it possible for the Bio-Manguinhos/Fiocruz Immunobiological Technology Institute to engage in the entire production of the Oxford/AstraZeneca vaccine (ChAdOx1 nCov-19) in Brazil, just 1.8 years after the COVID-19 pandemic was declared. The results were summarized in a case-based innovation model composed of 11 workstreams, 32 stages, 22 gates, 11 innovations, and 38 events. In terms of research contributions, three were found: (i) the identification of firm and government-level innovations allowing the substantial reduction in the COVID-19 vaccine time-to-market in Brazil; (ii) the presentation of empirical evidence supporting the new Outbreak Paradigm for vaccine research, development, and production; and (iii) the proposition of a conceptual model for describing innovations through the vaccine value chain in pandemic contexts, particularly when technology transfer is involved. 相似文献
82.
K. El-Boghdadly T. M. Cook T. Goodacre J. Kua S. Denmark S. McNally N. Mercer S. R. Moonesinghe D. J. Summerton 《Anaesthesia》2022,77(5):580-587
The impact of vaccination and new SARS-CoV-2 variants on peri-operative outcomes is unclear. We aimed to update previously published consensus recommendations on timing of elective surgery after SARS-CoV-2 infection to assist policymakers, administrative staff, clinicians and patients. The guidance remains that patients should avoid elective surgery within 7 weeks of infection, unless the benefits of doing so exceed the risk of waiting. We recommend individualised multidisciplinary risk assessment for patients requiring elective surgery within 7 weeks of SARS-CoV-2 infection. This should include baseline mortality risk calculation and assessment of risk modifiers (patient factors; SARS-CoV-2 infection; surgical factors). Asymptomatic SARS-CoV-2 infection with previous variants increased peri-operative mortality risk three-fold throughout the 6 weeks after infection, and assumptions that asymptomatic or mildly symptomatic omicron SARS-CoV-2 infection does not add risk are currently unfounded. Patients with persistent symptoms and those with moderate-to-severe COVID-19 may require a longer delay than 7 weeks. Elective surgery should not take place within 10 days of diagnosis of SARS-CoV-2 infection, predominantly because the patient may be infectious, which is a risk to surgical pathways, staff and other patients. We now emphasise that timing of surgery should include the assessment of baseline and increased risk, optimising vaccination and functional status, and shared decision-making. While these recommendations focus on the omicron variant and current evidence, the principles may also be of relevance to future variants. As further data emerge, these recommendations may be revised. 相似文献
83.
84.
《The Journal for Nurse Practitioners》2022,18(8):904-909
A 44-year-old man with a late presentation of coronavirus disease 2019 (COVID-19) pneumonia developed a left ventricular apical thrombus resulting in an asymptomatic anterior myocardial infarction due to extensive thrombosis of the left anterior descending artery. There are increasing reports of thrombotic complications in patients infected with COVID-19. This case highlights the risk of thrombotic events caused by severe acute respiratory syndrome-related corona virus-2 and the associated challenges in management. The objective of this case report is to generate primary literature and raise awareness and appreciation for cardiac manifestations of COVID-19. 相似文献
85.
86.
87.
《Vaccine》2022,40(24):3320-3329
BackgroundCurrently, booster dose is needed after 2 doses of non-live COVID-19 vaccine. With limited resources and shortage of COVID-19 vaccines, intradermal(ID) administration might be a potential dose-sparing strategy.ObjectiveTo determine immunologic response and reactogenicity of ID ChAdOx1 nCoV-19 vaccine (AZD1222,Oxford/AstraZeneca) as a booster dose after completion of 2-dose CoronaVac(SV) in healthy adult.MethodsThis is a prospective cohort study of adult aged 18–59 years who received 2-dose SV at 14–35 days apart for more than 2 months. Participants received ID AZD1222 at fractional low dose(1×1010 viral particles,0.1 ml). Antibody responses were evaluated by surrogate virus neutralization test(sVNT) against delta variant and wild type, and anti-spike-receptor-binding-domain immunoglobulin G(anti-S-RBD IgG) at prior, day14, 28, 90, and 180 post booster. Solicited reactogenicity was collected for 7 days post-booster. Primary endpoint was the differences of sVNT against delta strain ≥ 80% inhibition at day14 and 90 compared with the parallel cohort study of 0.5-ml intramuscular(IM) route.ResultsFrom August2021, 100 adults with median age of 46 years(IQR 41–52) participated. Prior to booster, geometric mean(GM) of sVNT against delta strain was 22.4% inhibition(95 %CI 18.7–26.9) and of anti-S-RBD IgG was 109.3 BAU/ml(95.4–125.1). Post ID booster, GMs of sVNT against delta strain were 95.5% inhibition (95%CI 94.2–96.8) at day14, 73.1% inhibition (66.7–80.2) at day90, and 22.7% inhibition (14.9–34.6) at day180. The differences of proportion of participants achieving sVNT against delta strain ≥ 80% inhibition in ID recipients versus IM were + 4.2% (95 %CI -2.0to10.5) at day14, and ?37.3%(-54.2to-20.3) at day90. Anti-S-RBD IgG GMs were 2037.1 BAU/ml (95%CI 1770.9–2343.2) at day14 and 744.6 BAU/ml(650.1–852.9) at day90, respectively. Geometric mean ratios(GMRs) of anti-S-RBD IgG were 0.99(0.83–1.20) at day14, and 0.82(0.66–1.02) at day90. Only 18% reported feverish, compared with 37% of IM (p = 0.003). Common reactogenicity was erythema at injection site(53%) while 7% reported blister.ConclusionLow-dose ID AZD1222 booster enhanced lower neutralizing antibodies at 3 months compared with IM route. Less systemic reactogenicity occurred, but higher local reactogenicity. 相似文献
88.
89.
《Human immunology》2022,83(12):803-807
We examined the correlation between class I HLA evolutionary divergence (HED), a surrogate for the capacity to present different peptides, and the outcomes of 234 adult inpatients with confirmed SARS-CoV-2 infection. Genomic DNA was extracted from peripheral blood and genotyped by next-generation sequencing (NGS). HED scores for HLA class I (HLA-A, -B, and -C) genotypes were calculated using Grantham’s distance. Higher HED scores for HLA-B, but not HLA-A or -C, are significantly associated with a decreased probability of poor outcomes including ICU admission, mechanical ventilation, and death (OR = 0.93; P = 0.04) in the univariate analysis. In the multivariate analysis, increased HLA-B HED score, younger age, and no comorbidity were independently associated with favorable outcomes (P = 0.02, P = 0.01, and P = 0.05, respectively). This finding is consistent with the notion that broader peptide repertoires presented by class I HLA may be beneficial in infection control. 相似文献
90.
Derek K. Chu Romina Brignardello-Petersen Gordon H. Guyatt Cristian Ricci Jon Genuneit 《Pediatric allergy and immunology》2022,33(1):e13609
Network meta-analyses (NMAs) simultaneously estimate the effects of multiple possible treatment options for a given clinical presentation. For allergists to benefit optimally from NMAs, they must understand the process and be able to interpret the results. Through a worked example published in Pediatric Allergy and Immunology, we summarize how to identify credible NMAs and interpret them with a focus on recent innovations in the GRADE approach (Grading of Recommendations Assessment, Development, and Evaluation). NMAs build on traditional systematic reviews and meta-analyses that consider only direct paired comparisons by including indirect evidence, thus allowing the simultaneous assessment of the relative effect of all pairs of competing alternatives. Our framework informs clinicians of how to identify credible NMAs and address the certainty of the evidence. Trustworthy NMAs fill a critical gap in providing key inferences using direct and indirect evidence to inform clinical decision making when faced with more than two competing courses of treatment options. This document will help allergists to identify trustworthy NMAs to enhance patient care. 相似文献