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   5723篇
  免费   531篇
  国内免费   309篇
耳鼻咽喉   33篇
儿科学   86篇
妇产科学   116篇
基础医学   733篇
口腔科学   121篇
临床医学   746篇
内科学   968篇
皮肤病学   80篇
神经病学   335篇
特种医学   190篇
外科学   719篇
综合类   822篇
现状与发展   2篇
一般理论   1篇
预防医学   310篇
眼科学   153篇
药学   501篇
  2篇
中国医学   228篇
肿瘤学   417篇
  2024年   16篇
  2023年   82篇
  2022年   208篇
  2021年   252篇
  2020年   200篇
  2019年   166篇
  2018年   215篇
  2017年   170篇
  2016年   170篇
  2015年   230篇
  2014年   291篇
  2013年   264篇
  2012年   422篇
  2011年   466篇
  2010年   264篇
  2009年   247篇
  2008年   314篇
  2007年   301篇
  2006年   270篇
  2005年   272篇
  2004年   219篇
  2003年   188篇
  2002年   159篇
  2001年   146篇
  2000年   144篇
  1999年   156篇
  1998年   95篇
  1997年   80篇
  1996年   74篇
  1995年   66篇
  1994年   55篇
  1993年   37篇
  1992年   49篇
  1991年   38篇
  1990年   38篇
  1989年   30篇
  1988年   27篇
  1987年   23篇
  1986年   25篇
  1985年   14篇
  1984年   14篇
  1983年   11篇
  1982年   6篇
  1981年   6篇
  1979年   10篇
  1973年   2篇
  1972年   4篇
  1971年   3篇
  1970年   6篇
  1969年   6篇
排序方式: 共有6563条查询结果,搜索用时 46 毫秒
91.
92.
93.
目的 构建个性化知识图谱技术和定性访谈法结合,进一步挖掘张忠德教授辨治间质性肺疾病临证特征与用药规律。方法 采用回顾性分析,系统收集张忠德教授广东省中医院门诊2010年8月至2020年8月治疗间质性肺疾病病历,按照诊断标准、纳入标准、排除标准,严格筛选后,通过广东省中医院大数据挖掘团队中医药大数据智能处理与知识服务系统进行数据挖掘分析,并通过多元化视觉定性访谈法,将定量与定性分析有效结合。结果 共筛选出347首方,共141味药物,常用药物频次 ≥ 84次的药物有10味,其中党参、麦芽、黄芪、紫菀、白术等为核心用药,通过症状与药物推理知识地图显示,党参、炒麦芽、黄芪、大枣、太子参、山萸肉、巴戟天等为主要治疗用药;临证遣方用药知识关联分析,得知咳嗽、耳鸣、心悸、水肿、头痛、胸闷、恶寒等为多见,针对咳嗽,首选紫苏子、橘红、桂枝等温肺降气通阳之品等;频繁聚集显示,常用药对炒麦芽-炒白术、黄芪-党参、黄精-菟丝子、前胡-紫菀、炙枇杷叶-浙贝母等;聚类分析结果得到4组关系密切的聚类新药物组合;以脾为中轴,肺肾共扶为主的“平调五脏论”,分期阶梯辨治间质性肺疾病。结论 张忠德教授认为间质性肺疾病,虚实夹杂为多见,应从肺、脾、肾着手,采用平调五脏论分期阶梯辨治,用药配伍精简,以和为贵,以平为期。  相似文献   
94.
95.
目的:探讨结构式手术交接单对改进冠状动脉介入术护理质量的效果。方法:采用非同期对照的方法,收集采用表单前后各6个月的50例行冠脉介入术的患者,观察术后交接率以及临床事件发生率,采用卡方检验比较前后差异。结果:实验组在皮下血肿、疼痛评估、臂围测量、对比剂用量以及尿量监测等5个方面的术后交接率分别上升14%、60%、46%,86%及52%;临床事件发生率下降14%;组间比较差异有统计学意义(P<0.05)。结论:改进后的结构式手术交接单,保证护理过程的完整、准确,显著提高围术期护理质量。  相似文献   
96.
Lgr5 was originally discovered as a common Wnt target gene in adult intestinal crypts and colon cancer. It was subsequently identified as an exquisite marker of multiple Wnt-driven adult stem cell types. Lgr5 and its homologs, Lgr4 and Lgr6, constitute the receptors for R-spondins, potent Wnt signal enhancers and stem cell growth factors. The Lgr5/R-spondin complex acts by neutralizing Rnf43 and Znrf3, two transmembrane E3 ligases that remove Wnt receptors from the stem cell surface. Rnf43/Znrf3 are themselves encoded by Wnt target genes and constitute a negative Wnt feedback loop. Thus, adult stem cells are controlled by an intricate interplay of potent Wnt agonists, antagonists, and anti-antagonists.  相似文献   
97.
α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors are considered to play a crucial role in synaptic plasticity in the developing visual cortex. In this study, we established a rat model of binocular form deprivation by suturing the rat binocular eyelids before eye-opening at postnatal day 14. During development, the decay time of excitatory postsynaptic currents mediated by α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors of normal rats became longer after eye-opening; however, the decay time did not change significantly in binocular form deprivation rats. The peak value in the normal group became gradually larger with age, but there was no significant change in the binocular form deprivation group. These findings indicate that binocular form deprivation influences the properties of excitatory postsynaptic currents mediated by α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors in the rat visual cortex around the end of the critical period, indicating that form stimulation is associated with the experience-dependent modification of neuronal synapses in the visual cortex.  相似文献   
98.
99.
Objectives: (1) To assess the ability of flow cytometric immunophenotyping to detect and quantitate eosinophils in patients with eosinophilic otitis media (EOM). (2) to evaluate the association of EOM to bronchial asthma.

Methods: Twenty-one patients with chronic otorrhea or middle ear effusion (MEE) were included in this prospective cohort study. Group I composed of 10 patients (14 ears) and associated to bronchial asthma. Group II included 11 patients (11 ears) without bronchial asthma. Samples of MEE were sent for flow cytometric analysis at initial presentation. Patients with positive eosinophils on flow cytometric immunophenotyping were analyzed after one-month course of dexamethasone eardrops.

Results: EOM was diagnosed in all patients of group I and in three patients of group II. The mean eosinophils percentage was 43.5% and 14.2% for group I and group II, respectively (p?=?.006). Those patients showed a significant response to dexamethasone eardrops, both on clinical examination and on flow cytometric analysis with a decrease in eosinophil levels post-treatment. However, this improvement was temporary and symptoms recurred after treatment cessation. Bronchial asthma was not associated to all patients with EOM.

Conclusion: Diagnosis of EOM remained mostly clinical; flow cytometry immunophenotyping of MEE may be helpful as an additional tool in diagnosis and monitoring the response to treatment, particularly in non-asthmatic patients.  相似文献   
100.
Mounting evidence has recently underscored the importance of DNA methylation in normal brain functions. DNA methylation machineries are responsible for dynamic regulation of methylation patterns in discrete brain regions. In addition to methylation of cytosines in genomic DNA (5-methylcytosine; 5mC), other forms of modified cytosines, such as 5-hydroxymethylcytosine, 5-formylcytosine, and 5-carboxylcytosine, can potentially act as epigenetic marks that regulate gene expression. Importantly, epigenetic modifications require cognate binding proteins to read and translate information into gene expression regulation. Abnormal or incorrect interpretation of DNA methylation patterns can cause devastating consequences, including mental illnesses and neurological disorders. Although DNA methylation was generally considered to be a stable epigenetic mark in post-mitotic cells, recent studies have revealed dynamic DNA modifications in neurons. Such reversibility of 5mC sheds light on potential mechanisms underlying some neurological disorders and suggests a new route to correct aberrant methylation patterns associated with these disorders.  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