全文获取类型
收费全文 | 336167篇 |
免费 | 30488篇 |
国内免费 | 7726篇 |
专业分类
耳鼻咽喉 | 4426篇 |
儿科学 | 5667篇 |
妇产科学 | 5095篇 |
基础医学 | 28492篇 |
口腔科学 | 11101篇 |
临床医学 | 35572篇 |
内科学 | 31523篇 |
皮肤病学 | 4011篇 |
神经病学 | 17897篇 |
特种医学 | 9601篇 |
外国民族医学 | 29篇 |
外科学 | 29257篇 |
综合类 | 52621篇 |
一般理论 | 27篇 |
预防医学 | 49707篇 |
眼科学 | 3273篇 |
药学 | 38023篇 |
508篇 | |
中国医学 | 33274篇 |
肿瘤学 | 14277篇 |
出版年
2024年 | 515篇 |
2023年 | 6436篇 |
2022年 | 10120篇 |
2021年 | 15524篇 |
2020年 | 16410篇 |
2019年 | 16064篇 |
2018年 | 14099篇 |
2017年 | 13751篇 |
2016年 | 12468篇 |
2015年 | 11921篇 |
2014年 | 24032篇 |
2013年 | 24349篇 |
2012年 | 21662篇 |
2011年 | 23148篇 |
2010年 | 18042篇 |
2009年 | 16257篇 |
2008年 | 15268篇 |
2007年 | 15246篇 |
2006年 | 13015篇 |
2005年 | 10986篇 |
2004年 | 9089篇 |
2003年 | 8044篇 |
2002年 | 6170篇 |
2001年 | 5422篇 |
2000年 | 4600篇 |
1999年 | 3800篇 |
1998年 | 3005篇 |
1997年 | 2700篇 |
1996年 | 2238篇 |
1995年 | 2282篇 |
1994年 | 2126篇 |
1993年 | 1771篇 |
1992年 | 1632篇 |
1991年 | 1439篇 |
1990年 | 1231篇 |
1989年 | 1207篇 |
1988年 | 1086篇 |
1987年 | 948篇 |
1986年 | 845篇 |
1985年 | 2191篇 |
1984年 | 2375篇 |
1983年 | 1470篇 |
1982年 | 1917篇 |
1981年 | 1351篇 |
1980年 | 1185篇 |
1979年 | 1021篇 |
1978年 | 824篇 |
1977年 | 613篇 |
1976年 | 765篇 |
1975年 | 510篇 |
排序方式: 共有10000条查询结果,搜索用时 88 毫秒
1.
2.
《Journal of pediatric surgery》2023,58(7):1274-1280
BackgroundPerianal abscesses and anal fistulas are common. The principle of intention-to-treat has not been considered in previous systemic reviews. Thus, the comparison between primary and post-recurrence management was confused, and the recommendation of primary treatment is obscure. The current study aims to identify the optimal initial treatment for pediatric patients.MethodsUsing PRISMA guidelines, studies were identified from MEDLINE, EMBASE, PubMed, Cochrane Library, and Google Scholar without any language or study design restriction. The inclusion criteria include original articles or articles with original data, studies of management for a perianal abscess with or without anal fistula, and patient age of <18 years. Patients with local malignancy, Crohn's disease, or other underlying predisposing conditions were excluded. Studies without analyzing recurrence, case series of <5, and irrelevant articles were excluded in the screening stage. Of the 124 screened articles, 14 articles had no full texts or detailed information. Articles written in a language other than English or Mandarin were translated by Google Translation first and confirmed with native speakers. After the eligibility process, studies that compared identified primary managements were then included in the qualitative synthesis.ResultsThirty-one studies involving 2507 pediatric patients met the inclusion criteria. The study design consisted of two prospective case series of 47 patients and retrospective cohort studies. No randomized control trials were identified. Meta-analyses for recurrence after initial management were performed with a random-effects model. Conservative treatment and drainage revealed no difference (Odds ratio [OR], 1.222; 95% Confidential interval [CI]: 0.615–2.427, p = 0.567). Conservative management had a higher risk of recurrence than surgery without statistical significance (OR 0.278, 95% CI: 0.109–0.707, p = 0.007). Compared with incision/drainage, surgery can prevent recurrence remarkably (OR 4.360, 95% CI: 1.761–10.792, p = 0.001). Subgroup analysis of different approaches within conservative treatment and operation was not performed for lacking information.ConclusionStrong recommendations cannot be made due to the lack of prospective or randomized controlled studies. However, the current study based on real primary management supports initial surgical intervention for pediatric patients with perianal abscesses and anal fistula to prevent recurrence.Level of evidenceType of study: Systemic review; Evidence level: Level II. 相似文献
3.
《The Journal of thoracic and cardiovascular surgery》2023,165(1):301-326
ObjectiveThe use of mechanical circulatory support (MCS) in lung transplantation has been steadily increasing over the prior decade, with evolving strategies for incorporating support in the preoperative, intraoperative, and postoperative settings. There is significant practice variability in the use of these techniques, however, and relatively limited data to help establish institutional protocols. The objective of the AATS Clinical Practice Standards Committee (CPSC) expert panel was to review the existing literature and establish recommendations about the use of MCS before, during, and after lung transplantation.MethodsThe AATS CPSC assembled an expert panel of 16 lung transplantation physicians who developed a consensus document of recommendations. The panel was broken into subgroups focused on preoperative, intraoperative, and postoperative support, and each subgroup performed a focused literature review. These subgroups formulated recommendation statements for each subtopic, which were evaluated by the entire group. The statements were then developed via discussion among the panel and refined until consensus was achieved on each statement.ResultsThe expert panel achieved consensus on 36 recommendations for how and when to use MCS in lung transplantation. These recommendations included the use of veno-venous extracorporeal membrane oxygenation (ECMO) as a bridging strategy in the preoperative setting, a preference for central veno-arterial ECMO over traditional cardiopulmonary bypass during the transplantation procedure, and the benefit of supporting selected patients with MCS postoperatively.ConclusionsAchieving optimal results in lung transplantation requires the use of a wide range of strategies. MCS provides an important mechanism for helping these critically ill patients through the peritransplantation period. Despite the complex nature of the decision making process in the treatment of these patients, the expert panel was able to achieve consensus on 36 recommendations. These recommendations should provide guidance for professionals involved in the care of end-stage lung disease patients considered for transplantation. 相似文献
4.
5.
《Research in social & administrative pharmacy》2022,18(9):3694-3698
In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area. 相似文献
6.
7.
8.
目的 多样的环境因素使得不同产地栽培滇重楼的化学成分也丰富多样,不同居群栽培滇重楼的甾体皂苷类成分具有很大的差异,多源数据融合分析能更全面的表征药材化学信息,建立一个高效而准确的产地鉴别模型,为其资源合理开发利用提供依据。方法 以来自云南和四川的8个产地(保山、楚雄、大理、红河、丽江、成都、文山、玉溪)共366份栽培滇重楼根茎为实验材料,采集其傅里叶变换近红外光谱(FT-NIR)和衰减全反射-傅里叶变换中红外光谱(ATR-FTMIR)数据。采用Kennard-Stone算法将不同产地的样品分为2/3的训练集和1/3的预测集,基于4种特征变量提取方法(CARS、VIP、SPA、SO-Covsel)结合2种数据融合策略(低级数据融合和中级数据融合),建立偏最小二乘产地判别分析模型。根据模型参数交叉验证均方根误差(RMSECV)和预测均方根误差(RMSEP)评估模型的稳定性,模型训练集和预测集准确率(ACC)评估模型分类性能。结果 近红外光谱和中红外光谱均能反应不同产地栽培滇重楼的化学成分差异,在中级数据融合中,基于VIP和SPA提取的特征变量建立的模型正确率均大于94%。相较于中级数据融合,低级数据融合模型得到了最为满意的结果,其预测集分类正确率达到100%。结论 根据近红外和中红外数据建立的低级数据融合PLS-DA模型,能够用于栽培滇重楼的产地鉴别分析。 相似文献
9.
目的探讨对前列腺癌患者采用一体化管理老年综合评估(CGA)护理模式对其心理因素和生活质量的影响。方法选取2020年3月至2021年3月在南京市第一医院就诊,确诊为前列腺癌,且首次行腹腔镜下前列腺癌根治术的患者96例,随机分为对照组、观察1组、观察2组,各32例。对照组为住院后采用常规护理模式进行护理,观察1组为入院后行CGA干预组,观察2组为一体化管理的CGA干预组。三组患者分别在干预前、出院时,进行焦虑自评量表(SAS)、抑郁自评量表(SDS)测评;在干预前、术后30 d,进行生活质量核心量表QLQ-C30(V3.0)和前列腺癌特异性补充量表QLQ-PR25测评。结果出院时,观察2组SAS、SDS评分显著优于对照组及观察1组(P<0.05);术后30 d,观察2组生活质量QLQ-C30、QLQ-PR25评分显著优于对照组及观察1组(P<0.05)。结论一体化管理CGA护理模式可有效改善前列腺癌患者的心理状态,提高其术后生活质量。 相似文献
10.