全文获取类型
收费全文 | 17159篇 |
免费 | 1036篇 |
国内免费 | 66篇 |
专业分类
耳鼻咽喉 | 215篇 |
儿科学 | 520篇 |
妇产科学 | 381篇 |
基础医学 | 2525篇 |
口腔科学 | 910篇 |
临床医学 | 1994篇 |
内科学 | 3310篇 |
皮肤病学 | 362篇 |
神经病学 | 1553篇 |
特种医学 | 308篇 |
外科学 | 1395篇 |
综合类 | 127篇 |
一般理论 | 10篇 |
预防医学 | 2061篇 |
眼科学 | 300篇 |
药学 | 1132篇 |
中国医学 | 84篇 |
肿瘤学 | 1074篇 |
出版年
2024年 | 19篇 |
2023年 | 180篇 |
2022年 | 355篇 |
2021年 | 684篇 |
2020年 | 408篇 |
2019年 | 612篇 |
2018年 | 653篇 |
2017年 | 468篇 |
2016年 | 466篇 |
2015年 | 570篇 |
2014年 | 741篇 |
2013年 | 923篇 |
2012年 | 1456篇 |
2011年 | 1577篇 |
2010年 | 768篇 |
2009年 | 678篇 |
2008年 | 1164篇 |
2007年 | 1104篇 |
2006年 | 1036篇 |
2005年 | 930篇 |
2004年 | 789篇 |
2003年 | 753篇 |
2002年 | 724篇 |
2001年 | 102篇 |
2000年 | 78篇 |
1999年 | 73篇 |
1998年 | 138篇 |
1997年 | 87篇 |
1996年 | 74篇 |
1995年 | 61篇 |
1994年 | 59篇 |
1993年 | 54篇 |
1992年 | 35篇 |
1991年 | 39篇 |
1990年 | 36篇 |
1989年 | 16篇 |
1988年 | 19篇 |
1987年 | 25篇 |
1986年 | 28篇 |
1985年 | 22篇 |
1984年 | 27篇 |
1983年 | 28篇 |
1982年 | 29篇 |
1981年 | 25篇 |
1980年 | 25篇 |
1979年 | 17篇 |
1977年 | 11篇 |
1976年 | 8篇 |
1975年 | 10篇 |
1930年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
131.
Paula Francekovi Lucía García-Torralba Eleni Sakoulogeorga Tea Vu
kovi Federico J. A. Perez-Cueto 《Nutrients》2021,13(4)
The meat production industry is one of the leading contributors of greenhouse gas emissions. Cultured meat presents itself as a potential eco- and animal-friendly meat substitute which has the potential to eradicate animal cruelty and reduce both the environmental footprint and the risk of zoonotic illnesses, while delivering a nutrient-dense product. The purpose of this study was to investigate how consumers perceive cultured meat and if the frequency of meat consumption is related to their intention of trying or purchasing cultured meat. Data were collected online in 2020 from Croatia, Greece, and Spain. Among the 2007 respondents, three segments were identified according to meat consumption and variety, plus an a priori identified group of “non-meat eaters”. Sixty percent perceived cultured meat as kind to animals, 57% as unnatural, 45% as healthy and environmentally-friendly, 21% as disgusting, and only 16% as tasty. Although 47% of the respondents had not heard of cultured meat before, 47% would taste it and 41% would purchase it for the same price as conventional meat. This indicates that consumers from Croatia, Greece and Spain might be likely to purchase cultured meat if sold at an affordable price. 相似文献
132.
María-Jos de Castro Paula Snchez-Pintos Nisreem Abdelaziz-Salem Rosaura Leis María L. Couce 《Nutrients》2021,13(6)
Children with inborn errors of intermediary metabolism (IEiM) must follow special diets that restrict their intake of essential nutrients and may compromise normal growth and development. We evaluated body composition, bone mineral density, physical activity, and food intake in IEiM patients undergoing dietary treatment. IEiM patients (n = 99) aged 5–19 years and healthy age- and sex-matched controls (n = 98) were recruited and underwent dual-energy X-ray absorptiometry to evaluate anthropometric characteristics and body composition. Data on food intake and physical activity were also collected using validated questionnaires. The height z-score was significantly lower in IEiM patients than controls (−0.28 vs. 0.15; p = 0.008), particularly in those with carbohydrate and amino acid metabolism disorders. Significant differences in adiposity were observed between patients and controls for the waist circumference z-score (−0.08 vs. −0.58; p = 0.005), but not the body mass index z-score (0.56 vs. 0.42; p = 0.279). IEiM patients had a significantly lower total bone mineral density (BMD) than controls (0.89 vs. 1.6; p = 0.001) and a higher risk of osteopenia (z-score < −2, 33.3% vs. 20.4%) and osteoporosis (z-score < −2.5, 7.1% vs. 0%), but none presented fractures. There was a significant positive correlation between natural protein intake and BMD. Our results indicate that patients with IEiM undergoing dietary treatment, especially those with amino acid and carbohydrate metabolism disorders, present alterations in body composition, including a reduced height, a tendency towards overweight and obesity, and a reduced BMD. 相似文献
133.
Habib Ndema Steyn Petrus S. Boydell Victoria Cordero Joanna Paula Nguyen My Huong Thwin Soe Soe Nai Dela Shamba Donat Kiarie James 《Health services & outcomes research methodology》2021,21(2):188-205
Health Services and Outcomes Research Methodology - An interrupted time series with a parallel control group (ITS-CG) design is a powerful quasi-experimental design commonly used to evaluate the... 相似文献
134.
Stehr Paula Weber Winja Rossmann Constanze 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2021,64(1):37-44
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Der Anteil älterer Personen in der Bevölkerung wächst stetig. Gleichzeitig steigen im Alter die Risiken für... 相似文献
135.
Tony Wawina-Bokalanga Bert Vanmechelen Valentine Lhermitte Joan Martí-Carreras Valentijn Vergote Fara Raymond Koundouno Joseph Akoi-Bor Ruth Thom Tom Tipton Kimberley Steeds Kita Balla Moussa Ablam Amento Lies Laenen Sophie Duraffour Martin Gabriel Paula Ruibal Yper Hall Mandy Kader-Kond Stephan Günther Guy Baele Cesar Muoz-Fontela Johan Van Weyenbergh Miles W. Carroll Piet Maes 《Emerging infectious diseases》2021,27(1):76
We investigated the genetic profiles of killer cell immunoglobulin-like receptors (KIRs) in Ebola virus–infected patients. We studied the relationship between KIR–human leukocyte antigen (HLA) combinations and the clinical outcomes of patients with Ebola virus disease (EVD). We genotyped KIRs and HLA class I alleles using DNA from uninfected controls, EVD survivors, and persons who died of EVD. The activating 2DS4–003 and inhibitory 2DL5 genes were significantly more common among persons who died of EVD; 2DL2 was more common among survivors. We used logistic regression analysis and Bayesian modeling to identify 2DL2, 2DL5, 2DS4–003, HLA-B-Bw4-Thr, and HLA-B-Bw4-Ile as probably having a significant relationship with disease outcome. Our findings highlight the importance of innate immune response against Ebola virus and show the association between KIRs and the clinical outcome of EVD. 相似文献
136.
Ralf Berger Jurandir Marcondes Ribas Filho Osvaldo Malafaia Paulo Afonso Nunes Nassif Eduardo Nascimento Silva Alfredo Benjamin Duarte da Silva Milka Takejima Marcelo Augusto de Souza Pedro Henrique de Paula Mrio Rodrigues Montemor Netto Lucia de Noronha 《Acta cirúrgica brasileira / Sociedade Brasileira para Desenvolvimento Pesquisa em Cirurgia》2021,36(5)
137.
Evangelista André Nobre dos Santos Flávia Franciele de Oliveira Martins Lorena Pacheco Gaiad Thais Peixoto Machado Alex Sander Dias Rocha-Vieira Etel Costa Karine Beatriz Santos Ana Paula Oliveira Murilo Xavier 《Lasers in medical science》2021,36(6):1201-1208
Lasers in Medical Science - The aim of the present study was to investigate the effects of photobiomodulation (PBM) therapy on the expression of heat shock protein 70 (HSP70) and tissue repair in... 相似文献
138.
Barroso Rosmeire Aparecida Navarro Ricardo Tim Carla Roberta de Paula Ramos Lucas de Oliveira Luciane Dias Araki Ângela Toshie Fernandes Karina Gonzales Camara Macedo Daniela Assis Lívia 《Lasers in medical science》2021,36(6):1235-1240
Lasers in Medical Science - Acne vulgaris is the most recurring skin condition in the world, causing great harm to the physical and psychological well-being of many patients. Antimicrobial... 相似文献
139.
Carlos Jiménez Romero Laura Alonso Murillo Paula Rioja Conde Alberto Marcacuzco Quinto Óscar Caso Maestro Anisa Nutu Isabel Pérez Moreiras Iago Justo Alonso 《Cirugía espa?ola》2021,99(6):440-449
IntroductionThere is controversy regarding the ideal pancreaticojejunostomy technique after pancreaticoduodenectomy. Many authors consider the external Wirsung stenting technique to be associated with a low incidence of fistula, morbidity and mortality. We analyse our experience with this technique.Patients and methodsA retrospective analysis of the morbidity and mortality of a series of 80 consecutive patients who had been treated surgically over a 6.5-year period for pancreatic head or periampullary tumors, performing pancreaticoduodenectomy and pancreaticojejunostomy with external Wirsung duct stenting.ResultsMean patient age was 68.3 ± 9 years, and the resectability rate was 78%. The texture of the pancreas was soft in 51.2% of patients and hard in 48.8%. Pylorus-preserving resection was performed in 43.8%. Adenocarcinoma was the most frequent tumor (68.8%), and R0 was confirmed in 70% of patients. Biochemical fistula was observed in 11.2%, pancreatic fistula grade B in 12.5% and C in 2.5%, whereas the abdominal reoperation rate was 10%. Median postoperative hospital stay was 16 days, and postoperative and 90-day mortality was 2.5%. Delayed gastric emptying was observed in 36.3% of patients, de novo diabetes in 12.5%, and exocrine insufficiency in 3. Patient survival rates after 1, 3 and 5 years were 80.2, 53.6 and 19.2%, respectively.ConclusionsAlthough our low rates of postoperative complications and mortality using external Wirsung duct stenting coincides with other more numerous recent series, it is necessary to perform a comparative analysis with other techniques, including more cases, to choose the best reconstruction technique after pancreaticoduodenectomy. 相似文献
140.
Mya L. Roberson Matthew D. Egberg Paula D. Strassle Michael R. Phillips 《Journal of pediatric surgery》2021,56(3):439-445
BackgroundThere is a limited understanding of the impact of pediatric malnutrition indicators on post-operative outcomes.Materials and methodsAll pediatric surgical patients captured in the ACS NSQIP-Pediatric database from 2016 to 2018 were included. Multivariable logistic regression was used to estimate odds of 30-day post-operative infection by malnutrition definition (stunted, wasted, requiring nutritional support, pre-operative hypoalbuminemia).ResultsAmong pediatric surgery patients (n = 282,056), 19% of patients met one definition of malnutrition, 6% met two, 1% met 3, and < 0.1% met all 4. After adjustment, requiring nutritional support (OR 1.47, 95% CI 1.36–1.60), stunting (OR 1.17, 95% CI 1.10–1.25), and hypoalbuminemia (OR 1.17 95% CI 1.04–1.32) were associated with increased odds of post-operative infection while wasting was not. Requiring nutritional support was associated in an increase of 10.17 days (95% CI 9.89–10.44) in time from admission to surgery.ConclusionsThe metric used to define malnutrition changed the association with post-operative outcomes. Nutritional supplementation, stunting, and hypoalbuminemia were associated with poorer postoperative outcomes. These findings have implications for pre-operative patient level counseling, accurate risk stratification, surgical planning, and patient optimization in pediatric surgery.Level of EvidenceIII. 相似文献