首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   254307篇
  免费   28955篇
  国内免费   15567篇
耳鼻咽喉   2889篇
儿科学   3242篇
妇产科学   3314篇
基础医学   19466篇
口腔科学   6162篇
临床医学   32033篇
内科学   32067篇
皮肤病学   2478篇
神经病学   11102篇
特种医学   15837篇
外国民族医学   44篇
外科学   24597篇
综合类   45987篇
现状与发展   82篇
一般理论   8篇
预防医学   28086篇
眼科学   5897篇
药学   25339篇
  605篇
中国医学   26646篇
肿瘤学   12948篇
  2024年   795篇
  2023年   5165篇
  2022年   10608篇
  2021年   13359篇
  2020年   12449篇
  2019年   7476篇
  2018年   7904篇
  2017年   6778篇
  2016年   7931篇
  2015年   9178篇
  2014年   20054篇
  2013年   18287篇
  2012年   25083篇
  2011年   24871篇
  2010年   18660篇
  2009年   13738篇
  2008年   11606篇
  2007年   13959篇
  2006年   11862篇
  2005年   8301篇
  2004年   7596篇
  2003年   7096篇
  2002年   5788篇
  2001年   5171篇
  2000年   4336篇
  1999年   4150篇
  1998年   3203篇
  1997年   2871篇
  1996年   1839篇
  1995年   1176篇
  1994年   868篇
  1993年   719篇
  1992年   1421篇
  1991年   1196篇
  1990年   1114篇
  1989年   529篇
  1988年   571篇
  1987年   450篇
  1986年   375篇
  1985年   130篇
  1984年   78篇
  1983年   38篇
  1982年   26篇
  1981年   10篇
  1980年   8篇
  1979年   3篇
  1976年   3篇
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
131.
文章回顾中医体质研究40年来在6大理论创新、3大技术创新、4大转化应用、2大学术平台方面取得的辉煌成就。展望未来,中医体质研究将积极策应国家需求,进一步发挥其原创优势、深化理论研究、完善技术方法、加快平台建设、提升服务能力,为实施“健康中国”战略作贡献。  相似文献   
132.
《Neuropsychopharmacology》2019,85(11):956-965
BackgroundBinge eating and other forms of disordered eating behavior (DEB) are associated with failed inhibitory control. This study investigated the neural correlates of failed inhibitory control as a potential biomarker for DEB.MethodsThe study used prospective longitudinal data from the European IMAGEN study adolescent cohort. Participants completed baseline assessments (questionnaires and a brain scan [functional magnetic resonance imaging]) at 14 years of age and a follow-up assessment (questionnaires) at 16 years of age. Self-reported binge eating and/or purging were used to indicate presence of DEB. Neural correlates of failed inhibition were assessed using the stop signal task. Participants were categorized as healthy control subjects (reported no DEB at both time points), maintainers (reported DEB at both time points), recoverers (reported DEB at baseline only), and developers (reported DEB at follow-up only). Forty-three individuals per group with complete scanning data were matched on gender, age, puberty, and intelligence (N = 172).ResultsAt baseline, despite similar task performance, incorrectly responding to stop signals (failed inhibitory control) was associated with greater recruitment of the medial prefrontal cortex and anterior cingulate cortex in the developers compared with healthy control subjects and recoverers.ConclusionsGreater recruitment of the medial prefrontal and anterior cingulate regions during failed inhibition accords with abnormal evaluation of errors contributing to DEB development. As this precedes symptom onset and is evident despite normal task performance, neural responses during failed inhibition may be a useful biomarker of vulnerability for DEB. This study highlights the potential value of prospective neuroimaging studies for identifying markers of illness before the emergence of behavior changes.  相似文献   
133.
134.
135.
136.
目的 了解医学生学习《健康教育》课程的满意度、需求度现状及差异,为《健康教育》课程优化提供参考。方法 以某医科大学在校临床医学生为研究对象,分析医学生对课程内容的需求度和满意度及二者差异。课程内容包括服药依从性、戒烟干预、合理膳食、心理压力管理、中医康复技术、慢性传染病健康教育、急性传染病健康教育、移动健康技术教育、运动康复指导及健康促进理论。采用频数和构成比指标进行统计描述,采用卡方检验进行健康教育课程学习情况与专业/ 学制之间、相关课程内容学习的需求度与学制的差异,相关课程内容学习需求度与满意度的关联比较采用秩和检验。以P < 0.05 为差异具有统计学意义。结果 戒烟干预、合理膳食、心理压力管理、中医康复技术、慢性传染病健康教育、急性传染病健康教育、移动健康技术教育及健康促进理论八项的学习需求度在长学制医学生与五年制医学生中的总体分布位置不同(U = 2.4、2.2、2.5、2.3、2.4、2.4、2.3、2.0,P 均< 0.05);服药依从性、戒烟干预、合理膳食、心理压力管理、慢性传染病健康教育、急性传染病健康教育、移动健康技术教育及运动康复指导八项的满意度与需求度之间的总体位置分布不同(U = 6.2、5.2、7.2、9.2、5.9、6.1、2.1、3.2,P 均< 0.05);不同学制的医学生对于慢性病人、老年人、孕产妇、传染病人、高危人群和职业暴露人群的健康教育重点关注人群侧重有所不同,其差异具有统计学意义(χ2 = 8.9、14.2、9.9、6.9、23.9、17.8,P 均< 0.05);在教学方式上,不同学制的医学生对于教师课堂讲授和小组讨论的偏好上的差异具有统计学意义(χ2=6.3、9.5,P 均< 0.05)。结论 当前健康教育课程的教学内容和结构未能完全满足不同学制、年级医学生的学习需求,需要对课程教学内容、教学方式和开设时间进行进一步的优化设计。  相似文献   
137.
薄层色谱鉴别在历版《中国药典》中的应用经历了从无到有、从少到多的过程;而薄层扫描含量测定在最近几版《中国药典》中的应用比例逐渐降低。随着对中药质量标准体系要求的进一步提高,薄层色谱法的不足之处陆续显现,如仪器普及率低、设备并不简单、结果重复性和稳定性较差、鉴别速度及准确性不及高效液相色谱法、展开剂毒性大等,逐渐不合时宜。在制定中药质量标准时,研究者不应该墨守成规,薄层色谱鉴别也不应该是雷打不动的定性鉴别必备选项。高效液相色谱法具备完全取代薄层色谱法的可行性,薄层色谱法可作为高效液相色谱法的补充。为充分降低检测成本、缩短检测周期、提高鉴别效率,笔者建议中药质量标准体系应该大幅减少薄层色谱鉴别方法的应用,增加高效液相特征图谱鉴定,尽量做到“一个条件,一张图谱”;除非确有必要,《中国药典》等国家质量标准体系应将薄层色谱鉴别作为推荐方法,而非强制标准。  相似文献   
138.
139.
《Injury》2023,54(2):362-369
BackgroundWe aimed to evaluate the biomechanical stiffness and strength of different internal fixation configurations and find suitable treatment strategies for low transcondylar fractures of the distal humerus.Methods and materialsThirty 4th generation composite humeri were used to create low transcondylar fracture models that were fixed by orthogonal and parallel double plates as well as posterolateral plate and medial screw (PPMS) configurations (n=10 in each group) using an anatomical locking compression plate-screw system and fully threaded medial cortical screws. Posterior bending (maximum 50 N), axial loading (maximum 200 N) and internal rotation (maximum 10 N·m) were tested, in that order, for each specimen. Stiffness under different biomechanical settings among different configurations were compared. Another 18 sets of fracture models were created using these three configurations (n=6 in each group) and the load to failure under axial loading among different configurations was compared.ResultsUnder posterior bending, the stiffness of parallel group was higher than orthogonal group (P<0.001), and orthogonal group was higher than PPMS group (P<0.001). Under axial loading, the stiffness of parallel group was higher than orthogonal group (P=0.001) and PPMS group (P<0.001); however, the difference between orthogonal and PPMS group was not statistically significant (P>0.05). Under internal rotation, the stiffness of parallel group was higher than orthogonal group (P=0.044), and orthogonal group was higher than PPMS group (P=0.029). In failure test under axial loading, the load to failure in the orthogonal group was lower than parallel group (P=0.009) and PPMS group (P=0.021), but the difference between parallel group and PPMS group was not statistically significant (P>0.05). All specimens in orthogonal group demonstrated “distal medial failure”; most specimens had “distal medial and trochlear failure” in the parallel group; most specimens exhibited “contact failure” in the PPMS group.ConclusionFor treating low transcondylar fractures, the overall stiffness and strength of the parallel configuration were superior to those of the orthogonal and PPMS configurations. Nevertheless, the PPMS configuration can provide adequate stability and stiffness comparable to double-plate configurations under axial loading. Therefore, the PPMS construct may have certain clinical value.  相似文献   
140.
BackgroundHeavy metal contamination has become a serious issue in this century especially detected in fish organs. Due to the presence of radioactive compounds in agricultural and sewage effluent, which destroys aquatic ecosystems, threatening human livelihoods. Health hazards associated with low and high consumption consumers assessed in five commercial fish species collected from Hurghada City, Egypt, during winter and summer, 2020. Atomic absorption spectrophotometer technique used for determination heavy meals in different organs and expressed as μg/g wet weight.ResultsHeavy metal concentrations in muscle ranged between:(0.054–0.109), (0.260–1.043), (0.264–0.897), (5.895–11.898), (0.381–0.970), (13.582–29.133) and (0.332–0.589) µg/g for Cd, Pb, Mn, Zn, Cu, Fe and Ni respectively, which were lower than those of gills and liver. These concentrations were within WHO, FAO/WHO, and EU standards. Consumption of edible species was lower than the (TDIs) established by the (JECFA) and Egyptian Standards. Even though THQ and TTHQ values were < 1 while, in children with highly consumer were> 1.ConclusionThis study concluded that intake of Red Sea fish is safe for human health. It is critical for consumers to be aware of the consequences of excessive fish consumption, particularly children with highly consumer, which represent possible health risks.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号