全文获取类型
收费全文 | 10659篇 |
免费 | 1756篇 |
国内免费 | 416篇 |
专业分类
耳鼻咽喉 | 84篇 |
儿科学 | 235篇 |
妇产科学 | 120篇 |
基础医学 | 814篇 |
口腔科学 | 216篇 |
临床医学 | 1231篇 |
内科学 | 1201篇 |
皮肤病学 | 130篇 |
神经病学 | 552篇 |
特种医学 | 225篇 |
外国民族医学 | 5篇 |
外科学 | 562篇 |
综合类 | 2381篇 |
预防医学 | 2481篇 |
眼科学 | 145篇 |
药学 | 912篇 |
8篇 | |
中国医学 | 892篇 |
肿瘤学 | 637篇 |
出版年
2024年 | 26篇 |
2023年 | 227篇 |
2022年 | 455篇 |
2021年 | 743篇 |
2020年 | 817篇 |
2019年 | 508篇 |
2018年 | 455篇 |
2017年 | 503篇 |
2016年 | 576篇 |
2015年 | 516篇 |
2014年 | 992篇 |
2013年 | 902篇 |
2012年 | 877篇 |
2011年 | 887篇 |
2010年 | 655篇 |
2009年 | 513篇 |
2008年 | 478篇 |
2007年 | 472篇 |
2006年 | 370篇 |
2005年 | 301篇 |
2004年 | 230篇 |
2003年 | 196篇 |
2002年 | 153篇 |
2001年 | 146篇 |
2000年 | 124篇 |
1999年 | 94篇 |
1998年 | 80篇 |
1997年 | 43篇 |
1996年 | 49篇 |
1995年 | 47篇 |
1994年 | 50篇 |
1993年 | 42篇 |
1992年 | 28篇 |
1991年 | 22篇 |
1990年 | 36篇 |
1989年 | 22篇 |
1988年 | 17篇 |
1987年 | 26篇 |
1986年 | 17篇 |
1985年 | 19篇 |
1984年 | 17篇 |
1983年 | 17篇 |
1982年 | 17篇 |
1981年 | 9篇 |
1980年 | 10篇 |
1979年 | 12篇 |
1978年 | 8篇 |
1977年 | 9篇 |
1976年 | 11篇 |
1974年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Hideya Yamamoto Yasuki Kihara Shinichiro Fujimoto Hiroyuki Daida Kazuhiro Kobuke Yoshitaka Iwanaga Shunichi Miyazaki Tomohiro Kawasaki Takashi Fujii Sachio Kuribayashi 《Journal of Cardiovascular Computed Tomography》2021,15(2):148-153
BackgroundWhether coronary plaque characteristics assessed in coronary computed tomography angiography (CCTA) in association with the coronary artery calcium score (CACS) have predictive value for coronary events is unclear. We aimed to examine the predictive value of the CACS and plaque characteristics for the occurrence of coronary events.MethodsAmong 2802 patients who were analyzed in the PREDICT registry, 2083 with suspected coronary artery disease (CAD) were studied using post hoc analysis. High-risk plaques were defined as having ≥2 adverse characteristics, such as low computed tomographic attenuation, positive remodeling, spotty calcification, and napkin-ring sign. An adjudicative composite of coronary events (cardiac death, nonfatal acute coronary syndrome, and coronary revascularization ≥3 months after indexed CCTA) were analyzed.ResultsSeventy-three (3.5%) patients had coronary events and 313 (15.0%) had high-risk plaques. Multivariate Cox proportional hazard analysis showed that high-risk plaques remained an independent predictor of coronary events (adjusted hazard ratio [HR] 1.95, 95% confidence interval [CI] 1.13–3.34, P ?= ?0.0154), as well as the log-transformed CACS (adjusted HR 1.24, 95% CI 1.11–1.39, P ?= ?0.0002) and the presence of obstructive stenosis (adjusted HR 5.63, 95% CI 3.22–10.12, P 0.0001). In subgroup analyses, high-risk plaques were independently predictive only in the low CACS class (<100).ConclusionThis study shows that assessment of adverse features by coronary plaque imaging independently predicts coronary events in patients with suspected CAD and a low CACS. Our findings suggest that the clinical value of high-risk plaques to CACS and stenosis assessment appears marginal. 相似文献
22.
《Sleep medicine》2021
ObjectivesInsomnia is a common problem affecting young adult cancer survivors (YACS) even years after treatment, yet it often goes unidentified and untreated. The Insomnia Severity Index is a widely-used insomnia measure, but has not been studied as an insomnia screener for YACS. The goal of this study was to validate the ISI in YACS by determining its utility in identifying YACS with insomnia disorder diagnosed with the Structured Clinical Interview for the DSM-5 (SCID-5).Methods250 YACS completed the ISI and SCID-5 Insomnia Module. Area under the curve (AUC) was calculated to reflect the ISI's discrimination between YACS with and without SCID-5 insomnia disorder. An ISI cut-off score with sensitivity ≥0.85 and specificity ≥0.75 was deemed acceptable.ResultsOf 250 participants, 52 met criteria for SCID-5 insomnia disorder diagnosis. The ISI had excellent discrimination, with an AUC = 0.91. A cut-off score ≥8 met study clinical screening criteria with sensitivity of 0.85 and specificity of 0.77. A cut-off score ≥7 with a higher sensitivity (0.96) but lower specificity (0.70) was noted as a potential alternative. Cut-off scores ≥12 and ≥ 14 were recommended for applications prioritizing overall accuracy.ConclusionsResults support validity of the ISI for identifying YACS with insomnia disorder. For clinical screening, data support the use of an ISI cut-off score ≥8 in YACS, and additional cut-off scores were found for research purposes or higher sensitivity. Results of this study and prior studies of the ISI offer important reminders that cut-off scores derived from different populations are not generalizable. 相似文献
23.
24.
目的探讨《临证指南医案》痹证用药特点。方法 运用数据挖掘技术统计药物使用频次、性味归经并进行关联规则、聚类、复杂网络分析等。结果 筛选出83首处方,共涉及中药125味,使用频次前5位依次为桂枝、茯苓、白术、当归、苦杏仁,功效类别以补虚药为主,性味以甘温最多,归经主要涉及肺、脾、肝、心、肾、胃;关联规则得到10对常见组合,高频中药聚为4类,复杂网络分析得到1个核心组合。结论 叶氏常从络病角度治痹,或通、或补、或通补皆施,重视肺脾,注重调和气血营卫,擅长通补奇经治法。 相似文献
25.
《European journal of surgical oncology》2021,47(8):1856-1861
The extent of peritoneal metastases (PM) largely determines the possibility of complete or optimal cytoreductive surgery in advanced ovarian cancer. An objective scoring system to quantify the extent of PM can help clinicians to decide whether or not to embark on CRS. Therefore several scoring systems have been developed by different research teams and this review summarizes their performance in predicting a complete or optimal cytoreduction in patients with advanced ovarian cancer. A systematic search in the MEDLINE database revealed 19 articles that described a total of five main scoring systems to predict the completeness of CRS in patients with FIGO stage III-IV ovarian cancer based on the surgical exploration of the abdominal cavity; PCI, PIV, Eisenkop, Espada, and Kasper. The Peritoneal Cancer Index (PCI) and the Predictive Index Value (PIV) were mentioned most frequently and showed AUCs of 0.69–0.92 and 0.66–0.98, respectively. Due to the use of different cut-offs sensitivities and specificities greatly varied. Therefore with the current data, no scoring system could be identified as best. An objective measure of the extent of disease can be of great clinical use for identifying ovarian cancer patients for which a complete (or optimal) CRS is achievable, however due to local differences in treatment strategies and surgical policy a widely adopted objective scoring system with a standard cut-off value is not feasible. Nevertheless, objective scoring systems can play an important role to guide treatment decisions. 相似文献
26.
矿化胶原材料是由胶原和羟基磷灰石组成的新型、有效的骨替代材料,多通过体外仿生学方法合成,模拟天然骨质的化学组成和结构,是一种严格的三维等级序列的多孔材料。因其具有良好的机械性能、生物相容性、骨传导性、骨诱导性和生物降解性等特性,在口腔医学中作为修复材料被广泛应用。文章就矿化胶原材料的性质、分类及其在口腔临床中的应用做一综述,以期为以后科学使用该种材料奠定基础。 相似文献
27.
28.
目的:为进一步深入研究和探讨肝阴虚证候的本质,本文分析和整理肝阴虚证的病因病机、证候表征、证候属性疾病及遣方选药的规律。方法:运用检索文献并进行频数统计的方法,检索查阅1960年9月1日至2019年1月10日中国知网中医临床研究文献。结果:肝阴虚证的病因病机为肝失疏泄,气机郁滞,化火伤阴,阴液亏虚,失于濡养;证候辨证要点主要为脉弦细数,舌红少津,头晕目眩,五心烦热,口咽干燥,两目干涩;证候临床属性疾病有肝炎、肝硬化、肝纤维化、肝癌;临床上治疗肝阴虚证使用处方主要为一贯煎、补肝汤、四物汤、芍药甘草汤,临床高频使用中药为生地黄、白芍、枸杞、当归、麦冬。结论:本文对于肝阴虚证的证候特点以及辨证用药规律做出系统的总结与归纳,将有关肝阴虚证的论述联系起来,形成统一的整体,为揭示肝阴虚证的本质与临床上形成较为成熟的肝阴虚证治疗方案提供参考。 相似文献
29.
30.
目的: 对海洋生物医用材料在医疗领域的应用情况和海洋生物材料来源医疗器械的安全性评价趋势进行分析,为推进该材料的临床转化提供参考。方法: 归纳海洋生物医用材料的分类和应用,介绍该材料的安全性评价的程序要点,探讨其安全性评价中面临的挑战。结果与结论: 常用的海洋生物医用材料主要为多糖和蛋白质,在创伤修复和组织工程领域应用广泛。海洋生物医用材料具有生物活性和良好的生物相容性,对此类材料的安全性评价应根据材料特性和预期用途,科学制定评价程序和选择检验方法。 相似文献