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   127212篇
  免费   12198篇
  国内免费   3719篇
耳鼻咽喉   954篇
儿科学   1888篇
妇产科学   1575篇
基础医学   13008篇
口腔科学   3897篇
临床医学   13291篇
内科学   15645篇
皮肤病学   1519篇
神经病学   8130篇
特种医学   3553篇
外国民族医学   11篇
外科学   9789篇
综合类   18545篇
现状与发展   8篇
一般理论   3篇
预防医学   22374篇
眼科学   1395篇
药学   15984篇
  127篇
中国医学   5889篇
肿瘤学   5544篇
  2024年   416篇
  2023年   2333篇
  2022年   4881篇
  2021年   6431篇
  2020年   6028篇
  2019年   5133篇
  2018年   4816篇
  2017年   5082篇
  2016年   5279篇
  2015年   5098篇
  2014年   9504篇
  2013年   9837篇
  2012年   8706篇
  2011年   9193篇
  2010年   6806篇
  2009年   6264篇
  2008年   5957篇
  2007年   5854篇
  2006年   4941篇
  2005年   4271篇
  2004年   3454篇
  2003年   3099篇
  2002年   2424篇
  2001年   2288篇
  2000年   1804篇
  1999年   1506篇
  1998年   1401篇
  1997年   1303篇
  1996年   1099篇
  1995年   993篇
  1994年   947篇
  1993年   738篇
  1992年   701篇
  1991年   593篇
  1990年   506篇
  1989年   504篇
  1988年   442篇
  1987年   378篇
  1986年   291篇
  1985年   385篇
  1984年   299篇
  1983年   179篇
  1982年   205篇
  1981年   157篇
  1980年   155篇
  1979年   116篇
  1978年   76篇
  1977年   54篇
  1976年   73篇
  1974年   41篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
111.
112.
The World Health Organization has reported an annual global suicide rate of 14.5 per 100,000 people. On the other hand, it is estimated that approximately one‐third of the global population are infected with Toxoplasma gondii (T. gondii) parasite. It is widely assumed that microbial pathogens, such as T. gondii, are probably associated with affective and behavioural modulation. The present article aimed to assess the proposed role of toxoplasmosis in raising the risk of suicidal ideation (SI) and suicide attempts (SA) using the available epidemiological data. Seven major electronic databases and the Internet search engine Google were searched for all the studies published between the 1st of January 1950 and 31st of October 2019. The heterogeneity and the risk of bias within and across studies were assessed. Following data extraction, pooled odds ratios (ORs) with 95% confidence interval (CI) across studies were calculated using the random‐effects models. A total number of 9,696 articles were screened and 27 studies were regarded as eligible in our systematic review (SI with five papers and 22 papers on SA). A significant association was detected between antibodies against T. gondii with TA (ORs = 1.57; 95% confidence interval [CI] 1.23–2.00, p = .000). Exploration of the association between T. gondii and SA yielded a positive effect of seropositivity for IgG antibodies but not IgM. Despite the limited number of studies, a statistical association was detected between suicidal behaviours and infection with latent T. gondii.  相似文献   
113.
目的分析新生儿重症监护病房(NICU)中重症肺炎新生儿多种菌感染危险因素。方法回顾分析2014年1月至2019年5月收入NICU的1 057例重症细菌肺炎新生儿的临床资料,分析其多种菌感染的危险因素。结果单因素分析显示,胎龄(37周)、出生体质量(2 500 g)、发病日龄(7 d)、羊水污染(Ⅱ、Ⅲ度)、感染类型(医院感染)、住院时间(≥14天)、机械通气、Apagar评分(7分)、胎膜早破、抗菌药物使用天数(≥10天)、更换抗菌药物(≥3种)、联合使用抗菌药物(≥3种)12个因素是NICU中重症肺炎新生儿多种菌感染的危险因素,差异有统计学意义(P均0.05)。多因素分析显示,更换抗菌药物(≥3种)、Apagar评分(7分)、感染类型(医院感染)、机械通气、羊水污染(Ⅱ、Ⅲ度)是NICU中重症肺炎新生儿多种菌感染的独立危险因素(P0.05)。结论临床应针对主要危险因素采取综合防控措施,减少NICU新生儿重症肺炎多种菌感染。  相似文献   
114.
目的鉴定河南省1例来自柬埔寨的登革热输入性病例的登革病毒(dengue virus,DENV)血清型和基因型及其序列特征和传播来源。方法患者血液标本来源于2019年国家疾病监测系统网络直报的登革热疑似病例。样品经快速检测DENV NS1抗原和IgM/IgG抗体,再提取血清中核酸,应用荧光RT-PCR法进行DENV血清型鉴定,同时用Vero和BHK-21细胞对血清标本进行病毒分离培养,阳性培养物扩增全基因组序列,进行序列系统进化分析。结果该病例实验室确诊为DENV 1型感染,并从血清标本中分离到病毒株,测序后拼接成全长10670 nt的全基因组序列,经系统进化分析,该病毒株属于DENV 1型基因Ⅰ型,与东南亚流行株具有较高同源性和较近亲缘关系。结论2019年河南省来自柬埔寨的输入性病例的病原体为DENV 1型基因I型,此为近年来东南亚输入我国的常见血清型和基因型。  相似文献   
115.
Human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) is one of the leading causes of morbidity and mortality in West Africa. Prevalence among the most productive age group in West and Central Africa stood at 1.5%, 3.4.0%, 2.5%, and 2.1% in 1990, 2000, 2010, and 2015 respectively. This study examined the effect of HIV/AIDS on economic growth in West Africa with focus on 11 countries. The augmented Solow model, rooted in the neoclassical growth theory, was used, which was operationalized using dynamic panel data modeling approach. Incidence, prevalence, number of people living with HIV/AIDS (PLWHA), and AIDS‐related deaths were used to measure HIV/AIDS. Estimations using system GMM returned statistically significant results while those of first difference and difference GMM were not. From the outcome of system GMM analysis, a percentage increase in incidence, prevalence, PLWHA, and AIDS deaths correspondingly reduced growth significantly through their effects on life expectancy by 0.15%, 0.02%, 0.004%, and 0.03%. Acquired immune deficiency syndrome deaths and PLWHA lowered economic growth through enrolment but not significantly. The import of the findings is that HIV/AIDS threatens growth through life expectancy in West Africa. Therefore, its spread in the subregion should be effectively contained while proper treatment should be provided for all infected persons.  相似文献   
116.
117.
Congenital heart disease is a rare but important finding in adults who experience sudden death. Examination of the congenitally malformed heart has historically been considered esoteric and best left to those with expertise. The Cardiac Risk in the Young cardiovascular pathology laboratory based at St George's University of London has now received over 6,000 cases. Of these, 21 congenitally malformed hearts were retained for research and educational purposes. Hearts were assessed using sequential segmental analysis, and causes of death were adjudicated based on thorough macroscopic examination and histology. Congenital malformations that were encountered included atrial septal defects, ventricular septal defects, tetralogy of Fallot, and transposition of the great arteries in both its regular and congenitally corrected variants. Findings also included hearts with mirror-imaged and isomeric atrial appendages. Direct causes of death included myocardial fibrosis, pulmonary hypertension, and hemorrhage. A small but notable proportion did not reveal a substrate for arrhythmia, raising the question of whether the terminal event was due to the congenital heart disease itself, or an underlying channelopathy. Here, we demonstrate the value of simple sequential segmental analysis in describing and categorizing the cases, with the concept of the “morphological method” serving to identify the distinguishing features of the cardiac components. Clin. Anat. 33:394–404, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
118.
鲍雨婷  王琴  陈金  魏力  郝雅楠 《天津护理》2020,28(6):648-652
目的: 应用文献计量学方法,分析国内外医用粘胶相关性皮肤损伤(Medical adhesive-related skin injuries,MARSI)文献的研究主题和热点。方法: 检索Cochrane Library、PubMed、EMbase、Web of science、sinoMed、CNKI、Wanfang、VIP等数据库MARSI相关文献,检索时限为建库至2019年5月。采用SPSS 22.0 软件进行文献计量分析,利用gCLUTO统计对国内外高频主题词进行聚类分析。结果: 共纳入论文103篇,其中外文文献占总文献量的27.18%,中文文献占总文献量的72.82%。聚类分析将国内外高频主题词聚为4大类,依次为皮肤损伤及损伤类型、相关危险因素、风险评估及风险管理、护理干预措施。结论: MARSI仍是国内外研究的热点,其发病机制研究仍处于探索阶段,目前尚缺乏有效的预防策略,研究领域较局限。在今后的研究中,应加强MARSI预防的研究、注重多学科合作。  相似文献   
119.
120.
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