全文获取类型
收费全文 | 7728篇 |
免费 | 391篇 |
国内免费 | 158篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 444篇 |
妇产科学 | 85篇 |
基础医学 | 265篇 |
口腔科学 | 91篇 |
临床医学 | 907篇 |
内科学 | 1152篇 |
皮肤病学 | 21篇 |
神经病学 | 147篇 |
特种医学 | 75篇 |
外科学 | 700篇 |
综合类 | 879篇 |
预防医学 | 2693篇 |
眼科学 | 20篇 |
药学 | 490篇 |
2篇 | |
中国医学 | 57篇 |
肿瘤学 | 232篇 |
出版年
2023年 | 158篇 |
2022年 | 342篇 |
2021年 | 417篇 |
2020年 | 344篇 |
2019年 | 387篇 |
2018年 | 328篇 |
2017年 | 256篇 |
2016年 | 288篇 |
2015年 | 271篇 |
2014年 | 626篇 |
2013年 | 496篇 |
2012年 | 445篇 |
2011年 | 540篇 |
2010年 | 441篇 |
2009年 | 387篇 |
2008年 | 341篇 |
2007年 | 349篇 |
2006年 | 271篇 |
2005年 | 271篇 |
2004年 | 207篇 |
2003年 | 140篇 |
2002年 | 123篇 |
2001年 | 116篇 |
2000年 | 71篇 |
1999年 | 62篇 |
1998年 | 58篇 |
1997年 | 48篇 |
1996年 | 39篇 |
1995年 | 29篇 |
1994年 | 38篇 |
1993年 | 19篇 |
1992年 | 15篇 |
1991年 | 21篇 |
1990年 | 19篇 |
1989年 | 19篇 |
1988年 | 16篇 |
1987年 | 13篇 |
1985年 | 23篇 |
1984年 | 45篇 |
1983年 | 30篇 |
1982年 | 31篇 |
1981年 | 34篇 |
1980年 | 26篇 |
1979年 | 10篇 |
1978年 | 12篇 |
1977年 | 11篇 |
1976年 | 10篇 |
1975年 | 6篇 |
1974年 | 7篇 |
1973年 | 6篇 |
排序方式: 共有8277条查询结果,搜索用时 15 毫秒
61.
Elizabeth Zanley Neha D. Shah Colleen Craig James N. Lau Homero Rivas Tracey McLaughlin 《Surgery for obesity and related diseases》2021,17(2):456-465
BackgroundPostbariatric hypoglycemia (PBH) affects up to 38% of Roux-en-Y gastric bypass (RYGB) patients. Severe cases are refractory to diet and medications. Surgical treatments including bypass reversal and pancreatectomy are highly morbid and hypoglycemia often recurs. We have developed a highly effective method of treatment by which enteral nutrition administered through a gastrostomy (G) tube placed in the remnant stomach replaces oral diet: if done correctly this reverses hyperinsulinemia and hypoglycemia, yielding substantial health and quality of life benefits for severely affected patients.ObjectivesTo provide clinical guidelines for placement of a G-tube to treat postRYGB hypoglycemia, including candidate selection, preoperative evaluation, surgical considerations, and post-RYGB management.SettingStanford University Hospital and Clinics.MethodsBased on our relatively large experience with placing and managing G-tubes for PBH treatment, an interdisciplinary task force developed guidelines for practitioners.ResultsA team approach (endocrinologist, dietitian, surgeon, psychologist) is recommended. Appropriate candidates have a history of RYGB, severe hypoglycemia refractory to medical-nutrition therapy, and significantly affected quality of life. Preoperative requirements include education and expectation setting, determination of initial enteral feeding program, and establishing service with a home enteral provider. Close postoperative follow-up is needed to ensure success and may require adjustments in formula and mode/rate of delivery to optimize tolerance and meet nutritional goals. G-tube nutrition must fully replace oral nutrition to prevent hypoglycemia.ConclusionsG-tube placement in the remnant stomach represents a relatively well-tolerated and effective treatment for severe, refractory hypoglycemia after RYGB. 相似文献
62.
63.
Yingdong Han Yun Zhang Yu Cao Yue Yin Xinxin Han Hong Di Xiaotian Chu Xuejun Zeng 《Translational andrology and urology》2021,10(1):272
BackgroundPrevious studies have suggested that the possible relationship between serum uric acid (SUA) and testosterone. However, the results of previous studies are controversial and there is limited evidence examining the relationship between SUA and testosterone in a general US population of men. The objective of this study is to explore the correlation of SUA and testosterone among adult males from the US.MethodsData from the National Health and Nutrition Examination Survey 2011–2016 were used, including a total of 7,796 male participants aged 18 years or older and excluding those lacking serum testosterone and uric acid data. Clinical characteristics of the participants among different SUA groups and testosterone groups are compared. Univariate and multivariate linear regression analyses were applied to evaluate the association between SUA and testosterone.ResultsWe found an inverse association between SUA and testosterone after fully adjusted the potential confounding factors in general US adult males. In the multivariate linear regression analysis, we found that increasing age (estimate testosterone percent difference: −0.20% per year, P<0.01), uric acid (estimate testosterone percent difference: −4.40% per md/dL, P<0.01) and BMI (estimate testosterone percent difference: −2.86% per kg/m2, P<0.01) were associated with declining serum testosterone. This association remained significant in sensitivity analysis, while in the stratified analysis, above association was not significant in men with diabetes or aged 65 and over.ConclusionsSUA levels might be negatively associated with serum testosterone in adult males. 相似文献
64.
Rachel B. Acton Sharon I. Kirkpatrick David Hammond 《Canadian journal of public health. Revue canadienne de santé publique》2021,112(4):647
InterventionThis study examined whether the impacts of sugar taxes and front-of-pack (FOP) nutrition labels differ across socio-demographic subgroups.Research questionWhat are the main and moderating effects of individual-level characteristics on the nutrient content of participants’ purchases in response to varying taxation levels and FOP labels?MethodsData from an experimental marketplace were analyzed. A sample of 3584 Canadians aged 13 years and older received $5 to purchase an item from a selection of 20 beverages and 20 snack foods. Participants were shown products with one of five FOP labels and completed eight within-subject purchasing tasks with different tax conditions. Linear mixed models were used to estimate the main and moderating effects of 11 individual-level variables on the sugars, sodium, saturated fats, and calorie content of participants’ purchases.ResultsParticipants who were younger, male, and more frequent consumers of sugary drinks purchased products containing more sugars, sodium, saturated fats, and calories. Sex and age moderated the relationship between tax condition and sugars or calories purchased: female participants were more responsive than males to a tax that included fruit juice, and younger participants were more responsive to all sugar tax conditions than older participants. Reported thirst and education level also moderated the relationship between tax condition and calories purchased. No individual-level characteristics moderated the effects of FOP labels.ConclusionA small proportion (7 of 176) of the moderating effects tested in this study were significant. Sugar taxes and FOP labelling policies may therefore produce similar effects across key socio-demographic groups.Supplementary InformationThe online version contains supplementary material available at 10.17269/s41997-021-00475-x. 相似文献
65.
《Gaceta sanitaria / S.E.S.P.A.S》2021,35(2):123-129
ObjectiveTo systematically describe the school nutritional policies of the 17 autonomous communities of Spain.MethodThrough a search of bibliographic databases, web pages and other official information systems, 183 documents of interest were identified. Information was systematically collected with the SNIPE (school nutrition index of programme effectiveness) questionnaire, adapted to Spain, and validated by reference staff of the regional government's health and education ministries.ResultsThe main objective of the policies is to prevent obesity and improve the nutrition of schoolchildren. The 17 autonomous communities cover the school canteen service, 11 cafeteria and vending machines, and 9 the breakfast service. All communities use the Consensus Document on School Food as a reference for the content of the menu and the nutritional quality of the products offered at the school; however, only 4 of them have regulated these aspects. The evaluation of policy objectives ranges from 58.8% of the autonomous communities for food supply to 5.9% for rotation and menu quality.ConclusionAlthough all the autonomous communities have standards for the school menu, the standards for the rest of the food supply vary across them; also, evaluation of objectives is scarce and only 4 communities have approved mandatory regulations. Nutritional standards should be reviewed according to current scientific knowledge and enacted by law, in compliance with the current legislation (Act 17/2011). 相似文献
66.
Conflicts of interest among scientific foundations and societies in the field of childhood nutrition
《Gaceta sanitaria / S.E.S.P.A.S》2021,35(4):320-325
ObjectiveTo describe food-industry sponsorships of associations active in the field of childhood nutrition and obesity prevention in Spain in 2017-2018.MethodThe associations were located at https://www.google.es/ using the words “society”, “foundation” or “federation” in combination with the terms “nutrition”, “obesity”, “childhood”, “paediatrics” and “diabetes”. Sponsorship was defined as the declaration of funding received or the appearance of a food company logo on an association's website or in the programmes of its congresses or courses. The percentage of sponsored societies and its association with the existence of ethical codes was calculated using MS Excel.Results64% of the associations displayed some type of sponsorship, with this being most frequent among paediatric and nutrition societies, 83% and 80% respectively, and non-existent among public health societies. No association was found between the existence of an ethical code and sponsorship (odds ratio: 0.75; 95% confidence interval: 0.14-3.94). The leading corporate sponsors were Nestlé, Coca-Cola and Danone. Whereas the initiatives of sponsored societies were targeted at changing eating individual behaviours, those of unsponsored societies sought to promote changes in the food system and eating environments.ConclusionsFood industry sponsorship of foundations and scientific societies is very widespread in Spain, except among public health associations. Unlike sponsored associations, those unsponsored propose policies opposed by the food industry, which are aimed at improving the system and food and eating environments. 相似文献
67.
68.
69.
目的 在“营养校园”试点学校进行为期一年的营养干预,分析评价干预效果。方法 在石家庄新华区选取一所小学和一所初中进行干预,从三、五、七年级中分别随机抽取2个班级的学生在干预前后进行调查。干预方法包括开展营养健康教育、促进身体活动、科学营养供餐支持等综合措施,通过问卷和体格测量调查学生干预前后的营养知识、饮食行为及超重肥胖变化情况。结果 干预后,营养知识题目的正确率显著提高(χ2=613.737,P<0.001),总体正确率为59.8%。学生早餐食物种类(χ2=19.841,P<0.001)和早餐摄入频率(χ2=5.405,P<0.05)均有显著改善。总体超重肥胖率未见显著改善,按性别、年级分层分析发现,女生超重肥胖率降低(χ2=1.891,P<0.05),5年级(χ2=4.923,P<0.05)和7年级(χ2=10.563,P<0.01)学生超重肥胖率降低,且高年级学生降幅更明显。结论 以校园为基础开展综合营养干预措施,可以提高学生的营养知识水平,并改善学生的不良饮食行为及超重肥胖现状。 相似文献
70.