全文获取类型
收费全文 | 555413篇 |
免费 | 40058篇 |
国内免费 | 14427篇 |
专业分类
耳鼻咽喉 | 5376篇 |
儿科学 | 17521篇 |
妇产科学 | 8622篇 |
基础医学 | 46672篇 |
口腔科学 | 12087篇 |
临床医学 | 60045篇 |
内科学 | 96483篇 |
皮肤病学 | 7294篇 |
神经病学 | 44418篇 |
特种医学 | 14295篇 |
外国民族医学 | 36篇 |
外科学 | 53615篇 |
综合类 | 80565篇 |
现状与发展 | 42篇 |
一般理论 | 38篇 |
预防医学 | 52735篇 |
眼科学 | 7615篇 |
药学 | 45476篇 |
560篇 | |
中国医学 | 38623篇 |
肿瘤学 | 17780篇 |
出版年
2023年 | 9530篇 |
2022年 | 13591篇 |
2021年 | 24420篇 |
2020年 | 23118篇 |
2019年 | 26212篇 |
2018年 | 24219篇 |
2017年 | 20952篇 |
2016年 | 18787篇 |
2015年 | 17947篇 |
2014年 | 35318篇 |
2013年 | 38503篇 |
2012年 | 31022篇 |
2011年 | 33513篇 |
2010年 | 26824篇 |
2009年 | 25142篇 |
2008年 | 24720篇 |
2007年 | 24891篇 |
2006年 | 21872篇 |
2005年 | 18646篇 |
2004年 | 15429篇 |
2003年 | 13416篇 |
2002年 | 10787篇 |
2001年 | 9592篇 |
2000年 | 7928篇 |
1999年 | 6869篇 |
1998年 | 5982篇 |
1997年 | 5506篇 |
1996年 | 4388篇 |
1995年 | 4530篇 |
1994年 | 4286篇 |
1993年 | 3521篇 |
1992年 | 3493篇 |
1991年 | 3034篇 |
1990年 | 2565篇 |
1989年 | 2253篇 |
1988年 | 2101篇 |
1987年 | 1864篇 |
1986年 | 1683篇 |
1985年 | 4527篇 |
1984年 | 5411篇 |
1983年 | 3726篇 |
1982年 | 4249篇 |
1981年 | 3913篇 |
1980年 | 3439篇 |
1979年 | 3151篇 |
1978年 | 2724篇 |
1977年 | 2069篇 |
1976年 | 2281篇 |
1975年 | 1682篇 |
1974年 | 1477篇 |
排序方式: 共有10000条查询结果,搜索用时 859 毫秒
11.
《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
12.
目的:探讨初诊急性白血病患者化疗期间应用伏立康唑进行预防侵袭性真菌病(IFD)的临床疗效及安全性。方法:回顾性分析2016年02月至2018年03月期间我院血液科收治的初诊急性白血病行化疗的患者166例,按照是否使用抗真菌药进行预防性治疗分为观察组(应用伏立康唑进行预防治疗,n=103)和对照组(未应用抗真菌药物,n=63),比较两组患者IFD发生率差异,并分析抗真菌药物应用的不良反应。结果:观察组IFD发生率为10.7%,对照组为33.3%,两组患者的IFD发生率有明显差异(P<0.05);所有应用伏立康唑进行预防治疗的患者均未出现严重的不良反应。结论:伏立康唑可以有效减低急性白血病患者化疗期间IFD发生率,并且有着较好的安全性,值得在临床推广应用。 相似文献
13.
Dongbing Lai Emma C. Johnson Sarah Colbert Gayathri Pandey Grace Chan Lance Bauer Meredith W. Francis Victor Hesselbrock Chella Kamarajan John Kramer Weipeng Kuang Sally Kuo Samuel Kuperman Yunlong Liu Vivia McCutcheon Zhiping Pang Martin H. Plawecki Marc Schuckit Jay Tischfield Leah Wetherill Yong Zang Howard J. Edenberg Bernice Porjesz Arpana Agrawal Tatiana Foroud 《Alcoholism, clinical and experimental research》2022,46(3):374-383
14.
15.
《Archivos de bronconeumología》2022,58(1):11-21
BackgroundWe aimed to describe the effectiveness and safety of inhaled antibiotics in chronic obstructive pulmonary disease (COPD) patients, as well as the patient profile in which they are usually prescribed and the patient groups that can most benefit from this treatment.MethodsMulticentre retrospective observational cohort study in COPD patients who had received ≥1 dose of inhaled antibiotics in the last 5 years. Clinical data from the two years prior to and subsequent to the start of the treatment were compared. Primary outcome: COPD exacerbations. Secondary outcomes: side effects, symptomatology (sputum purulence, dyspnoea), microbiological profile and pathogen eradication.ResultsOf 693 COPD patients analyzed (aged 74.1; 86.3% men; mean FEV1 = 43.7%), 71.7% had bronchiectasis and 46.6% presented chronic bronchial infection (CBI) by Pseudomonas aeruginosa (PA). After 1 year of treatment with inhaled antibiotics, there was a significant decrease in the number of exacerbations (?33.3%; P < .001), hospital admissions (?33.3%; P < .001) and hospitalization days (?26.2%; P = .003). We found no difference in effectiveness between patients with or without associated bronchiectasis. Positive patient outcomes were more pronounced in PA-eradicated patients. We found a significant reduction in daily expectoration (?33.1%; P = .024), mucopurulent/purulent sputum (?53.9%; P < .001), isolation of any potentially pathogenic microorganisms (PPM) (?16.7%; P < .001), CBI by any PPM (?37.4%; P < .001) and CBI by PA (?49.8%; P < .001). CBI by any PPM and ≥three previous exacerbations were associated with a better treatment response. 25.4% of patients presented non-severe side-effects, the most frequent of these being bronchospasm (10.5%), dyspnoea (8.8%) and cough (1.7%).ConclusionsIn COPD patients with multiple exacerbations and/or CBI by any PPM (especially PA), inhaled antibiotics appear to be an effective and safe treatment, regardless of the presence of bronchiectasis. 相似文献
16.
17.
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
18.
19.
20.