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   102579篇
  免费   9273篇
  国内免费   4864篇
耳鼻咽喉   808篇
儿科学   2914篇
妇产科学   1793篇
基础医学   12080篇
口腔科学   2394篇
临床医学   9961篇
内科学   16718篇
皮肤病学   1465篇
神经病学   7797篇
特种医学   1918篇
外国民族医学   31篇
外科学   8834篇
综合类   17357篇
现状与发展   13篇
预防医学   8206篇
眼科学   2872篇
药学   9715篇
  29篇
中国医学   3587篇
肿瘤学   8224篇
  2024年   101篇
  2023年   1147篇
  2022年   2205篇
  2021年   3342篇
  2020年   3180篇
  2019年   2904篇
  2018年   2885篇
  2017年   3290篇
  2016年   3648篇
  2015年   3624篇
  2014年   6404篇
  2013年   7210篇
  2012年   6668篇
  2011年   7410篇
  2010年   6128篇
  2009年   5824篇
  2008年   6057篇
  2007年   6117篇
  2006年   5486篇
  2005年   4836篇
  2004年   4105篇
  2003年   3547篇
  2002年   2945篇
  2001年   2537篇
  2000年   2164篇
  1999年   1797篇
  1998年   1472篇
  1997年   1278篇
  1996年   1130篇
  1995年   1138篇
  1994年   946篇
  1993年   757篇
  1992年   643篇
  1991年   548篇
  1990年   491篇
  1989年   377篇
  1988年   310篇
  1987年   252篇
  1986年   218篇
  1985年   311篇
  1984年   264篇
  1983年   150篇
  1982年   208篇
  1981年   135篇
  1980年   143篇
  1979年   92篇
  1978年   64篇
  1977年   53篇
  1976年   46篇
  1975年   35篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
1.
2.
3.
目的 探究影响我国老年人认知水平的变化趋势,分离出年龄、队列效应。方法 基于CLHLS(2002—2018)多重队列追踪数据,以Stata16.0软件为工具,运用分层生长曲线模型进行统计分析。结果 本研究发现,个体行为生活方式、社会经济地位、性别、慢性病数量对认知水平均具有统计学意义;年龄、队列对认知水平的变化具有独立效应;随着年龄的增长,我国老年人认知水平下降,认知水平的城乡、性别差异明显;较年轻出生队列的老年人认知水平较好,认知水平的城乡差异随着队列的年轻化而变大,性别差异在较年轻队列有略微缩小的趋势。结论 影响认知水平因素复杂,认知障碍会增加医疗成本及照护负担,因此需准确把握老年认知水平的变化规律与作用路径,从而为卫生服务、养老保障、长期医疗照护的资源配置提供科学依据。  相似文献   
4.
【目的】了解上海市闵行区小学生近视状况及相关因素分析。【方法】选取2019年1月1日至12月31日期间参加屈光筛查的11 356名6~10岁小学生作为本次研究的对象,调查项目包括视力检查和电脑验光。【结果】6~10岁社区小学生近视检出率45.59%。女性高于男性,6~10岁检出率分别为22.88%、31.77%、47.62%、60.53%、69.84%,呈线性趋势(χ2=1.31,P<0.001)。多因素logistic回归分析结果显示,性别、年龄、父母近视状态是社区小学生屈光近视的影响因素;出生体重、是否早产、体重指数(BMI)对社区小学生屈光近视无影响。【结论】社区儿童青少年屈光近视的检出率较高,且不同人群特征检出情况有所差异,因此需针对不同年龄段、不同学生特征儿童青少年采取综合施策优先,重点人群重点防控的多层次防控策略。  相似文献   
5.
ObjectiveThere is a paucity of data concerning the use of granulocyte colony-stimulating factors (G-CSFs) in pediatric patients with acute lymphoblastic leukemia (ALL). The aim of the present study was to evaluate the effect of G-CSF use on relapse-free and overall survival in 358 consecutive, newly diagnosed pediatric ALL patients uniformly treated at the same institution between April 2012 and April 2020.Materials and MethodsPatients were evaluated in two separate periods, based on the G-CSF treatment approach. All patients who underwent ALL treatment between April 2012 and December 2016 received G-CSF (G-CSF+ arm; n: 245) in the course of the protocol for reducing the risk of febrile neutropenia and/or inducing neutrophil recovery to prevent any treatment delay. No patients after December 2016 received G-CSF, even if they belonged to the high-risk group, and these were included in the G-CSF? arm (n: 113).ResultsEstimated mean relapse-free (106.5 months; 95 % CI 102?110.8 vs 82 months 95 % CI 75.2?88.9; p: 0.794) and overall survival (111.4 months; 95 % CI 108?114.8 vs 85 months 95 % CI 80.4?89.8; p: 0.431) rates were similar between the G-CSF+ and G-CSF? groups.ConclusionsOur findings indicate that G-CSF use during ALL treatment had no effect on relapse rates or overall survival.  相似文献   
6.
目的 探讨血液肿瘤患者接受化疗后发生肛周感染的危险因素。方法 采用回顾性病例对照研究的方法,对四川省某三级甲等医院血液内科2020年12月—2021年5月收治的进行化疗的348例血液肿瘤住院患者相关资料(人口学特征、疾病特征、医疗及护理病例记录、实验室检查结果)予以回顾性分析,根据出院诊断发生肛周感染的病例作为病例组,其余病例作为对照组,统计血液肿瘤患者接受化疗后肛周感染的发生率,采用单因素分析和二元Logistic回归分析肛周感染的危险因素。结果 348例血液肿瘤化疗患者,发生肛周感染35例,感染率为10.1%;Logistic回归分析显示,年龄<60岁(OR=8.776,P=0.039)、痔疮史(OR=7.733,P<0.001)、肛周感染史(OR=14.981,P<0.001)、腹泻(OR=3.893,P=0.019)及白细胞计数<1×109/L(OR=6.851,P=0.002)是血液肿瘤患者接受化疗后发生肛周感染的独立危险因素。结论 血液肿瘤患者接受化疗后肛周感染的发生率较高,年龄<60岁、痔疮史、肛周感染史、腹泻、白细胞计数<1×109/L导致血液肿瘤化疗患者肛周感染率增加,在护理化疗期的血液肿瘤患者过程中,应该结合肛周感染的危险因素,采取针对性干预措施,降低肛周感染发生率。  相似文献   
7.
《Vaccine》2022,40(19):2679-2695
Vaccinations are essential for preventing infectious diseases in children with chronic diseases as they have increased risk of infection from frequent use of biologics. Response to immunizations in this group is not well known.ObjectiveA systematic review was performed to evaluate three primary outcomes: efficacy; immunogenicity; and safety of vaccines in children with chronic conditions treated with biologics.MethodsThe protocol for our systematic review and meta-analysis was registered and published with PROSPERO. We searched electronic bibliographic databases for studies published from 2009 to 2019, focusing on vaccinations in children with chronic conditions treated with biologics.ResultsWe retrieved 532 records. Thirty-one full-text articles were selected, and 14 were included in the meta-analysis. No significant publication bias was found. Efficacy: limited data are available regarding the efficacy of vaccination, as most studies have focused on immunogenicity as surrogate outcome for efficacy. Immunogenicity: patients receiving anti-TNF-alpha therapy had a statistically significant risk of poor seroconversion (p = 0.028) and seroprotection by the serotype B influenza vaccine [inflammatory bowel disease (IBD) p = 0.013; juvenile idiopathic arthritis (JIA) p = 0.004]. We found adequate responses with H1N1 and H3N2 serotypes. Few studies existed for pneumococcal, hepatitis A virus, hepatitis B virus, varicella-zoster virus, Measles Mumps Rubella virus, and multiple vaccine administration. Safety: vaccine administration was not associated with serious side effects, but JIA patients on anti-TNF alpha therapy had a statistically significant risk of presenting with myalgia or arthralgia postinfluenza vaccine (p = 0.014).ConclusionsMore evidence concerning efficacy, immunogenicity, and safety of vaccinations is needed to guide physicians in the vaccine decision process for this pediatric population.  相似文献   
8.
In 2019, the scientists who discovered how cells sense and adapt to oxygen availability were awarded the Nobel Prize. This elegant sensing pathway is conserved throughout evolution, and it underpins the physiology and pathology that we, as clinicians in anaesthesia and critical care, encounter on a daily basis. The purpose of this review is to bring hypoxia-inducible factor, and the oxygen-sensing pathway as a whole, to the wider clinical community. We describe how this unifying mechanism was discovered, and how it orchestrates diverse changes such as erythropoiesis, ventilatory acclimatisation, pulmonary vascular remodelling and altered metabolism. We explore the lessons learnt from genetic disorders of oxygen sensing, and the wider implications in evolution of all animal species, including our own. Finally, we explain how this pathway is relevant to our clinical practice, and how it is being manipulated in new treatments for conditions such as cancer, anaemia and pulmonary hypertension.  相似文献   
9.
目的:探讨赣南地区原发性肺鳞癌患者EGFR和ALK基因突变的特点,科学指导此类患者优选靶向用药。方法:入组73例原发性肺鳞癌病例,采用ARMS-PNA技术检测EGFR基因第18、19、20、21外显子突变,应用不平衡法检测其中60例病例的ALK融合基因,回顾性分析EGFR和ALK基因突变患者的临床病理特征。结果:EGFR基因突变8例,阳性率为10.96%(8/73),4例为L858R突变,3例为19del突变,1例为G719X突变。女性患者突变率(66.67%,2/3)明显高于男性患者(8.57%,6/70)(P=0.030),EGFR基因突变在高龄(≥60岁)、进展期(N_(1-3)、Ⅲ+Ⅳ期)患者中相对较高,但差异无统计学意义(P>0.05)。EGFR基因突变与吸烟史、T分期以及肿瘤分布位置均无相关性(P>0.05);ALK融合基因表达2例,阳性率3.33%(2/60),与患者性别、年龄、吸烟史、TNM分期及肿瘤分布类型等各临床病理特征均无相关性(P>0.05);未发现EGFR和ALK基因共存突变病例。结论:赣南地区原发性肺鳞癌患者EGFR和ALK基因突变率相对不高,EGFR基因突变以L858R和19del突变为主,且好发于女性患者,可能是患者病情进展的预测因子之一。  相似文献   
10.
The objectives of this study were to factor analyze the Moral Distress Scale–Revised (MDS-R) in NICU nurses and to evaluate the relationships among dimensions of the MDS-R and the demoralization, exhaustion, and loss of motive dimensions of the Burnout Measure (BM). A total of 142 NICU nurses completed modified pen-and-paper versions of the MDS-R and BM. Exploratory and confirmatory factor analyses showed that the MDS-R-14 was a relatively good fit for the data. The compromised care dimension predicted BM demoralization (β = 0.24) and exhaustion (β = 0.22), the futile care dimension predicted BM exhaustion (β = 0.18), and the untruthful care dimension predicted BM demoralization (β = .25). Strategies to mitigate moral distress and resulting burnout in NICU nurses should address futile care, compromised care, and untruthful care.  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