全文获取类型
收费全文 | 80834篇 |
免费 | 9367篇 |
国内免费 | 1203篇 |
专业分类
耳鼻咽喉 | 233篇 |
儿科学 | 1584篇 |
妇产科学 | 812篇 |
基础医学 | 4542篇 |
口腔科学 | 1202篇 |
临床医学 | 18230篇 |
内科学 | 11471篇 |
皮肤病学 | 390篇 |
神经病学 | 5675篇 |
特种医学 | 1142篇 |
外国民族医学 | 4篇 |
外科学 | 5963篇 |
综合类 | 10102篇 |
现状与发展 | 1篇 |
一般理论 | 46篇 |
预防医学 | 16524篇 |
眼科学 | 323篇 |
药学 | 6305篇 |
188篇 | |
中国医学 | 4635篇 |
肿瘤学 | 2032篇 |
出版年
2024年 | 355篇 |
2023年 | 2234篇 |
2022年 | 2866篇 |
2021年 | 4632篇 |
2020年 | 4852篇 |
2019年 | 4208篇 |
2018年 | 3810篇 |
2017年 | 4070篇 |
2016年 | 3950篇 |
2015年 | 3894篇 |
2014年 | 6625篇 |
2013年 | 8444篇 |
2012年 | 5528篇 |
2011年 | 5525篇 |
2010年 | 4055篇 |
2009年 | 3670篇 |
2008年 | 3619篇 |
2007年 | 3491篇 |
2006年 | 2973篇 |
2005年 | 2214篇 |
2004年 | 1764篇 |
2003年 | 1529篇 |
2002年 | 1130篇 |
2001年 | 950篇 |
2000年 | 814篇 |
1999年 | 591篇 |
1998年 | 539篇 |
1997年 | 471篇 |
1996年 | 395篇 |
1995年 | 324篇 |
1994年 | 259篇 |
1993年 | 245篇 |
1992年 | 190篇 |
1991年 | 160篇 |
1990年 | 142篇 |
1989年 | 125篇 |
1988年 | 110篇 |
1987年 | 88篇 |
1986年 | 97篇 |
1985年 | 87篇 |
1984年 | 56篇 |
1983年 | 44篇 |
1982年 | 51篇 |
1981年 | 28篇 |
1980年 | 43篇 |
1979年 | 36篇 |
1978年 | 18篇 |
1977年 | 20篇 |
1976年 | 22篇 |
1974年 | 20篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Journal of the Academy of Nutrition and Dietetics》2022,122(11):2060-2071
BackgroundVoices for Food was a longitudinal community, food pantry–based intervention informed by the social ecological model, and designed to improve food security, dietary intake, and quality among clients, which was carried out in 24 rural food pantries across 6 Midwestern states.ObjectiveOur objective was to evaluate changes in adult food security, dietary intake, and quality from baseline (2014) to follow-up (2016), and to assess the role of adult food security on dietary outcomes.DesignA multistate, longitudinal, quasi-experimental intervention with matched treatment and comparison design was used to evaluate treatment vs comparison group changes over time and changes in both groups over time.Participants/settingAdult food pantry clients (n = 617) completed a demographic food security survey, and up to three 24-hour dietary recalls at baseline (n = 590) and follow-up (n = 160).InterventionCommunity coaching served as the experimental component, which only “treatment” communities received, and a food council guide and food pantry toolkit were provided to both “treatment” and matched “comparison” communities.Main outcome measuresChange in adult food security status, mean usual intakes of nutrients and food groups, and Healthy Eating Index-2010 scores were the main outcome measures.Statistical analyses performedLinear mixed models estimated changes in outcomes by intervention group and by adult food security status over time.ResultsImprovements in adult food security score (–0.7 ± 0.3; P = .01), Healthy Eating Index-2010 total score (4.2 ± 1.1; P < .0001), and empty calories component score (3.4 ± 0.5; P <.0001) from baseline to follow-up were observed in treatment and comparison groups, but no statistically significant changes were found for adult food security status, dietary quality, and usual intakes of nutrients and food groups between the 2 groups over time. The intervention effect on dietary quality and usual intake changes over time by adult food security status were also not observed.ConclusionsFood pantry clients in treatment and comparison groups had higher food security and dietary quality at the follow-up evaluation of the Voices for Food intervention trial compared with baseline, despite the lack of difference among the groups as a result of the experimental coaching component. 相似文献
2.
社会力量具备相应的经济基础和技术条件,对于公立互联网医院体系建设具有积极的促进作用。但是实践中仍然存在商业模式不完善、监管制度不健全等问题。基于经济学契约理论要义,提出在坚持激励与约束机制并举、平衡公私益关系的前提下,通过完善医保政策、构建互联网医疗服务价格分类管理机制来促进社会力量向医疗服务公益性目标回归,并通过构建完善的监督体制来约束部分社会力量的盲目逐利性行为。 相似文献
3.
贺利平 《实用中西医结合临床》2022,22(14)
目的 探讨胆囊结石合并胆总管结石(CBDS)术后患者复发情况及危险因素。方法 纳入114例2019年1月~2020年12月在本院行ECRP联合LC治疗的胆囊结石合并CBDS患者,回顾性分析其临床资料,根据所选患者ECRP联合LC术后随访1年内是否复发(REC)将其分为REC组(32例)和未REC组(82例)。回顾性统计胆囊结石合并CBDS术后患者REC情况,比较REC组和未REC组的临床资料,并分析胆囊结石合并CBDS术后患者REC的危险因素。结果 114例胆囊结石合并CBDS术后患者REC32例,发生率28.07%。胆囊结石合并CBDS术后患者REC的危险因素为胆道感染、胆道口括约肌切开、术者经验≤3年、胆道括约肌功能障碍(OR=4.170、4.047、3.568、3.367,P<0.05)。结论 胆囊结石合并CBDS术后患者REC的危险因素与胆道感染、胆道口括约肌切开、术者经验≤3年、胆道括约肌功能障碍密切相关,可据此针对性制定临床治疗及护理干预措施方案,以降低胆囊结石合并CBDS术后患者REC率。 相似文献
4.
《Journal of pediatric surgery》2023,58(9):1613-1617
BackgroundThe goal of this study was to characterize contemporary performance benchmarks and risk factors associated with negative appendectomy (NA) in children with suspected appendicitis.MethodsA multicenter retrospective cohort analysis of children undergoing appendectomy for suspected appendicitis was performed using data from the 2016–2021 NSQIP-Pediatric Appendectomy Targeted Public Use Files. Multivariable regression was used to evaluate the influence of year, age, sex, and WBC count on NA rate, and to generate rate estimates for NA based on different combinations of demographic characteristics and WBC profiles.Results100,322 patients were included from 140 hospitals. The overall NA rate was 2.4%, and rates decreased significantly during the study period (2016: 3.1% vs. 2021: 2.3%, p < 0.001). In adjusted analyses, the highest risk for NA was associated with a normal WBC (<9000/mm3; OR 5.31 [95% CI: 4.87–5.80]), followed by female sex (OR 1.55 [95% CI: 1.42–1.68]) and age <5 years (OR 1.64 [95% CI 1.39, 1.94]). Model-estimated risk for NA varied significantly across demographic and WBC strata, with a 14.4-fold range in rates between subgroups with the lowest and highest predicted risk (males 13–17 years with elevated WBC [1.1%] vs. females 3–4 years with normal WBC [15.8%]).ConclusionsContemporary NA rates have decreased over time, however NA risk remains high in children without a leukocytosis, particularly for girls and children <5 years of age. These data provide contemporary performance benchmarks for NA in children with suspected appendicitis and identify high-risk populations where further efforts to mitigate NA risk should be targeted.Level of EvidenceIII. 相似文献
5.
6.
目的:通过中英文文献了解结直肠癌患者生命质量研究现状及发展趋势。方法:运用CiteSpace对中国知网(CNKI)、万方数据知识服务平台、中国生物医学文献数据库、Web of Science核心数据集、PubMed、Cochrane Library中收录的关于结直肠癌患者生命质量研究的中英文文献进行可视化分析。结果:检索得到中文文献1 285篇,英文文献871篇,中英文文献发文量均呈上升趋势,相关研究关注的重点主要是结直肠癌患者造口、抑郁、免疫、肠道功能、化疗及化疗药物,但机构之间、学者之间合作程度及研究类型等方面存在一定差异。结论:中文文献相关研究起步晚、发展快,但在研究质量与研究深度等方面与英文文献相比还有一定差距;国内学者之间、机构之间应加强合作,关心患者肠道功能、心理状况,提高患者体力活动水平,开展更多高质量研究。 相似文献
7.
《Revista portuguesa de cardiologia》2022,41(4):299-307
AimsMyocardial strain analysis enables more precise assessment of cardiac performance but is relatively load dependent. New tools have been developed with afterload adjustment. Our objective was to assess myocardial work (MW) in patients with repaired aortic coarctation (rACo).MethodsProspective study of consecutive patients with rACo who underwent a routine transthoracic echocardiogram in 2018 and 2019 at our center. Patients with significant aortic valve disease, pacemaker, or other congenital heart diseases (except for mild bicuspid aortic valve disease) were excluded. Global longitudinal strain with two dimensional speckle tracking analysis and MW were obtained (GWI:Global Work Index; GCW: Global Constructive Work; GWW: Global Wasted Work; GWE: Global Work Efficiency). Blood pressure was measured in the patient's right arm.ResultsWe included 42 patients in the analysis, mean age of 37±10 years, 38% males. In this group, 52% had hypertension and 64% had a concomitant bicuspid aortic valve. In comparison to previously published reference values, patients with rACo had significantly lower GWI (1807 vs. 1896 mmHg%) and GCW (2173 vs. 2232 mmHg%) (p<0.001), particularly in males. Systolic blood pressure is an independent predictor for GWI (β=0.432) and for GCW (β=0.534) and GLS an independent predictor of all MW parameters (β>0.594). Neither age nor gender were independent predictors.ConclusionsIn patients with rACo, there are some signs of left ventricular dysfunction with a reduction in GCW and GWI and with preserved GWE, despite normal ejection fraction and strain. 相似文献
8.
9.
目的:探讨经皮冠状动脉介入(PCI)术后病人的体力活动水平及其影响因素。方法:选择常州市三级甲等综合医院心内科接受PCI治疗的冠心病病人,收集资料,分析PCI术后冠心病病人体力活动动机、体力活动和自我效能现状;冠心病病人自我效能、体力活动动机与体力活动的相关性,并分析影响PCI术后病人体力活动水平的相关危险因素。结果:共发放调查问卷400份,回收400份,有效率为94.75%(379/400);379例冠心病病人术后每周体力活动为(3570.85±314.19)MET-min,以低、中强度为主;冠心病病人术后自我效能总分、体力活动动机总分与体力活动呈正相关(P<0.05);体质指数(BMI)、PCI次数≥2次、年龄、PCI支架数量≥3枚、自我效能、体力活动动机是影响PCI术后冠心病病人体力活动水平的高危因素(OR>1且P<0.05)。结论:PCI术后病人体力活动水平处于较低的水平,PCI次数、BMI、年龄、PCI支架数量、自我效能、体力活动动机是影响PCI术后冠心病病人体力活动水平的高危因素,临床需针对各高危因素制定相应的干预措施,提高病人体力活动水平。 相似文献
10.
AimThe aim of the study was to describe the characteristics of the Bachelor’s thesis of fourth-year nursing students at a Spanish public university, the criteria that students used to choose a topic and students’ degree of satisfaction after completing the Bachelor’s thesis.DesignQuantitative study.MethodsWe examined 420 Bachelor’s theses carried out from 2013 to 2018 and conducted an online survey among fourth-year students in the 2017–18 and 2018–19 academic years (81 completed questionnaires).ResultsThe Bachelor’s thesis took the form of a research proposal. The most frequent proposal type was a qualitative hospital-based study whose objective was to understand the experiences of adult or adolescent patients, close family members, or nurses. Students chose topics for personal reasons. Most participants reported feeling satisfied with the knowledge and skills acquired.ConclusionsStudents completing a Bachelor’s thesis in the form of a research proposal have the potential to transfer their research skills to their nursing practice. 相似文献