全文获取类型
收费全文 | 327386篇 |
免费 | 27596篇 |
国内免费 | 11243篇 |
专业分类
耳鼻咽喉 | 2602篇 |
儿科学 | 5150篇 |
妇产科学 | 3443篇 |
基础医学 | 50919篇 |
口腔科学 | 5974篇 |
临床医学 | 28275篇 |
内科学 | 50682篇 |
皮肤病学 | 3975篇 |
神经病学 | 20726篇 |
特种医学 | 7069篇 |
外国民族医学 | 73篇 |
外科学 | 24629篇 |
综合类 | 48132篇 |
现状与发展 | 28篇 |
一般理论 | 31篇 |
预防医学 | 18895篇 |
眼科学 | 5849篇 |
药学 | 44662篇 |
56篇 | |
中国医学 | 15163篇 |
肿瘤学 | 29892篇 |
出版年
2024年 | 492篇 |
2023年 | 4943篇 |
2022年 | 7181篇 |
2021年 | 14510篇 |
2020年 | 11533篇 |
2019年 | 10735篇 |
2018年 | 10446篇 |
2017年 | 10408篇 |
2016年 | 10643篇 |
2015年 | 11653篇 |
2014年 | 18146篇 |
2013年 | 20500篇 |
2012年 | 17629篇 |
2011年 | 20409篇 |
2010年 | 17143篇 |
2009年 | 17322篇 |
2008年 | 17047篇 |
2007年 | 17231篇 |
2006年 | 15646篇 |
2005年 | 14577篇 |
2004年 | 12381篇 |
2003年 | 11121篇 |
2002年 | 8541篇 |
2001年 | 7780篇 |
2000年 | 6458篇 |
1999年 | 5935篇 |
1998年 | 4796篇 |
1997年 | 4348篇 |
1996年 | 4180篇 |
1995年 | 3838篇 |
1994年 | 3437篇 |
1993年 | 3045篇 |
1992年 | 2597篇 |
1991年 | 2332篇 |
1990年 | 1953篇 |
1989年 | 1744篇 |
1988年 | 1655篇 |
1987年 | 1309篇 |
1986年 | 1079篇 |
1985年 | 1471篇 |
1984年 | 1458篇 |
1983年 | 993篇 |
1982年 | 1084篇 |
1981年 | 889篇 |
1980年 | 764篇 |
1979年 | 618篇 |
1978年 | 457篇 |
1977年 | 375篇 |
1976年 | 403篇 |
1975年 | 261篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Md. Golzar Hossain Aneela Javed Sharmin Akter Sukumar Saha 《Journal of microbiology, immunology, and infection》2021,54(2):175-181
Coronavirus disease-19 (COVID-19) caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is now a pandemic threat. This virus is supposed to be spread by human to human transmission. Cellular angiotensin-converting enzyme 2 (ACE2) is the receptor of SARS-CoV-2 which is identical or similar in different species of animals such as pigs, ferrets, cats, orangutans, monkeys, and humans. Moreover, a recent study predicted that dogs might be secondary hosts during the evolution of SARS-CoV-2 from bat to human. Therefore, there is a possibility of spreading SARS-CoV-2 through domestic pets. There are now many reports of SARS-CoV-2 positive cases in dogs, cats, tigers, lion, and minks. Experimental data showed ferrets and cats are highly susceptible to SARS-CoV-2 as infected by virus inoculation and can transmit the virus directly or indirectly by droplets or airborne routes. Based on these natural infection reports and experimental data, whether the pets are responsible for SARS-CoV-2 spread to humans; needs to be deeply investigated. Humans showing clinical symptoms of respiratory infections have been undergoing for the COVID-19 diagnostic test but many infected people and few pets confirmed with SARS-CoV-2 remained asymptomatic. In this review, we summarize the natural cases of SARS-CoV-2 in animals with the latest researches conducted in this field. This review will be helpful to think insights of SARS-CoV-2 transmissions, spread, and demand for seroprevalence studies, especially in companion animals. 相似文献
22.
《Journal of microbiology, immunology, and infection》2021,54(4):748-751
IntroductionThe novel coronavirus disease (COVID-19) could cause a severe acute respiratory infectious disease, showing a high mortality rate of 12–45% among cases who required intensive care unit admission. COVID-19 pneumoniaPatients and methodsFor the purpose of identifying clinical manifestations and radiological findings of COVID-19 pneumonia, we reviewed all cases of COVID-19 pneumonia which were published by the homepage of the Japanese Association for Infectious Diseases from Feb 5 2020 until April 30 2020, including our cases. All patients were diagnosed based on positive results of the novel coronavirus-real-time RT-PCR with chest computed tomography (CT) findings.ResultsA total of 92 patients were enrolled in this study. The median age was 66 years (range 16–92 years). For all, 50 (54%) were males. The most common underlying disease was hypertension in 32 (36%). Any comorbidity was seen in 60 (67%). The mortality rate was 4 (6%). In terms of clinical symptoms on an initial visit, fever and cough were confirmed in 66 (72%) and 37 (40%). Forty-three (47%) had no respiratory symptoms. As for radiological findings by chest CT scan, ground-glass opacities (GGO)s, peripheral distribution, bilateral lung involvements were seen in 88 (96%), 76 (83%) and 78 (85%), respectively.ConclusionIt is difficult to diagnose as COVID-19 pneumonia due to poor respiratory symptoms. Chest CT findings typically show GGO, peripheral and bilateral shadows. Patients should have chest CT performed if suspected for early diagnosis and therapeutic intervention, resulting in a favorable outcome and prevention of secondary nosocomial transmitted infection. 相似文献
23.
《Journal of microbiology, immunology, and infection》2021,54(5):983-986
In an investigation of six anti-SARS-CoV-2 antibody kits with different target antigen and methodology, each kit showed comparable performance. As false-positive reactions occurred independently with different kits, specificity increased to 100% when pairs of kits were used. With three-kit combination, both sensitivity (99.1%) and specificity (100%) increased. 相似文献
24.
25.
26.
27.
28.
《Digestive and liver disease》2022,54(11):1486-1493
BackgroundCold snare polypectomy (CSP) is a promising technique for the removal of sessile serrated polyps (SSPs) ≥ 10 mm. However, the efficacy and safety of this technique remain undetermined.AimsWe aimed to comprehensively evaluate the efficacy and safety of CSP for SSPs ≥ 10 mm.MethodsPubMed, EMBASE, Web of Science and Cochrane Library were searched up to January 2021.ResultsA total of 10 studies consisting of 1727 SSPs (range, 10–40 mm) from 1021 patients were included. The overall rates of technical success, adverse events (AEs) and residual SSPs were 100%, 0.7% and 2.9%, respectively. Subgroup analysis showed that the rates of technical success and AEs were comparable between CSP and cold endoscopic mucosal resection (EMR) (99.9% vs. 100% and 1.3% vs. 0.5%, respectively), between the proximal and distal colon (100% vs. 99.9% and 0.3% vs. 0, respectively), and between polyps of 10–19 mm and ≥20 mm (99.8% vs. 100% and 0.9% vs. 0, respectively). However, subgroup analysis showed that the rate of residual SSPs was slightly lower in CSP compared with cold EMR (1.3% vs. 3.9%), as well as in polyps of 10–19 mm compared with those ≥20 mm (3.1% vs. 4.7%).ConclusionCSP was an effective and safe technique for removing SSPs ≥ 10 mm. 相似文献
29.
Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ12,14PGJ2 a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ12,14PGJ2 production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ2 and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment. 相似文献
30.