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   304852篇
  免费   14450篇
  国内免费   8390篇
耳鼻咽喉   2222篇
儿科学   8569篇
妇产科学   4265篇
基础医学   27720篇
口腔科学   4158篇
临床医学   29309篇
内科学   45989篇
皮肤病学   2137篇
神经病学   21344篇
特种医学   13768篇
外国民族医学   47篇
外科学   40550篇
综合类   31958篇
现状与发展   33篇
一般理论   3篇
预防医学   29794篇
眼科学   5796篇
药学   24365篇
  137篇
中国医学   10867篇
肿瘤学   24661篇
  2024年   186篇
  2023年   1529篇
  2022年   3182篇
  2021年   5165篇
  2020年   4597篇
  2019年   3628篇
  2018年   25371篇
  2017年   21307篇
  2016年   22897篇
  2015年   6485篇
  2014年   8070篇
  2013年   8536篇
  2012年   18287篇
  2011年   32818篇
  2010年   28260篇
  2009年   19932篇
  2008年   28468篇
  2007年   30542篇
  2006年   9018篇
  2005年   9347篇
  2004年   8852篇
  2003年   9243篇
  2002年   6432篇
  2001年   3358篇
  2000年   2787篇
  1999年   1925篇
  1998年   1176篇
  1997年   1254篇
  1996年   827篇
  1995年   729篇
  1994年   698篇
  1993年   413篇
  1992年   312篇
  1991年   320篇
  1990年   338篇
  1989年   219篇
  1988年   185篇
  1987年   152篇
  1986年   109篇
  1985年   82篇
  1984年   43篇
  1983年   48篇
  1982年   38篇
  1980年   48篇
  1974年   26篇
  1938年   60篇
  1937年   25篇
  1934年   31篇
  1932年   56篇
  1930年   46篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
72.
AimsThis retrospective study aims to analyze and explore the clinical characteristics, risk factors, and in-hospital outcomes - including return of spontaneous circulation (ROSC) and survival to discharge - of hospitalized patients admitted with acute coronary syndrome (ACS) suffering cardiac arrest.MethodsACS patients admitted to three tertiary hospitals in Fujian, China, were evaluated retrospectively from January 1, 2012 to December 30, 2016. Data were collected, based on the Utstein Style, for all cases of attempted resuscitation for IHCA. We analyzed patient characteristics, pre-event variables, event variables, and the main outcomes, including ROSC and survival to discharge, and identified the influencing factors on the outcomes.ResultsThe total number of ACS admissions across the three hospitals during this study period was 21,337. Among these admissions, 320 ACS patients experienced IHCA (incidence: 1.50%); 134 (41.9%) patients experienced ROSC; and 68 (21.2%) survived to discharge. The findings indicated that four factors were associated with ROSC, including age <70 years-old, shockable rhythm, duration of resuscitation (≤15 min and 16–30 min), and PCI. Five factors were associated with survival to discharge, including age <70 years-old, shockable rhythm, the duration of resuscitation (≤15 min and 16–30 min), Killip ≤ II, and CCI ≤ 2.ConclusionYounger age, shockable rhythm, and shorter duration of resuscitation were all factors demonstrated to be a predictor of ROSC and survival to hospital discharge.  相似文献   
73.

Previous systematic reviews have found a higher sero-prevalence of EBV antibodies in SLE patients compared with controls. Because many studies have been published, there is a need to apply more precise systematic review methods. We examined the association between EBV and SLE patients by conducting a systematic review and meta-analysis of case–control studies that examined the prevalence of EBV antibodies and the DNA-positive rate. We searched the MEDLINE and EMBASE databases from 1966 to 2018 with no language restrictions. The Mantel–Haenszel odds ratios (OR) for EBV antibody sero-positivity were calculated, and meta-analyses were conducted. Quality assessment was performed using a modified version of the Newcastle–Ottawa scale, and 33 studies were included. Most studies found a higher sero-prevalence of VCA IgG and EA IgG in SLE patients compared with controls. Meta-analysis demonstrated a significantly higher OR for sero-positivity to VCA IgG and EA IgG for SLE cases (2.06 [95% confidence interval (CI) 1.30–3.26, p = 0.002] and 7.70, [95% CI 4.64–12.76, p < 0.001], respectively). The overall OR for the DNA-positive rate for SLE patients compared with controls was 3.86 (95% CI 1.52–9.83, p = 0.005). Other antibodies, i.e., VCA IgA/IgM, EBNA IgA, and EA IgA/IgM, also demonstrated a significant difference between SLE patients and controls. These findings support previous systematic reviews; however, publication bias cannot be excluded. The methodological conduct of studies could be improved, particularly when selecting controls and analyses of laboratory conduct.

  相似文献   
74.
Han  Xin  Xiao  Yi  Tang  Yi  Zheng  Xiaonan  Anwar  Mawluda  Qin  Wei 《Clinical and experimental medicine》2019,19(4):479-486
Clinical and Experimental Medicine - IgA nephropathy (IgAN) is the most common glomerulonephritis worldwide. The classic manifestation of IgAN is episodic hematuria and proteinuria. Nephrotic...  相似文献   
75.
76.
77.
In the search for a therapeutic schedule for spinal cord injury, it is necessary to understand key genes and their corresponding regulatory networks involved in the spinal cord injury process. However, ad hoc selection and analysis of one or two genes cannot fully reveal the complex molecular biological mechanisms of spinal cord injury. The emergence of second-generation sequencing technology(RNA sequencing) has provided a better method. In this study, RNA sequencing technology was used to analyze differentially expressed genes at different time points after spinal cord injury in rat models established by contusion of the eighth thoracic segment. The numbers of genes that changed significantly were 944, 1362 and 1421 at 1, 4 and 7 days after spinal cord injury respectively. After gene ontology analysis and temporal expression analysis of the differentially expressed genes, C5ar1, Socs3 and CCL6 genes were then selected and identified by real-time polymerase chain reaction and western blot assay. The mRNA expression trends of C5ar1, Socs3 and CCL6 genes were consistent with the RNA sequencing results. Further verification and analysis of C5ar1 indicate that the level of protein expression of C5ar1 was consistent with its nucleic acid level after spinal cord injury. C5ar1 was mainly expressed in neurons and astrocytes. Finally, the gene Itgb2,which may be related to C5ar1, was found by Chilibot database and literature search. Immunofluorescence histochemical results showed that the expression of Itgb2 was highly consistent with that of C5ar1. Itgb2 was expressed in astrocytes. RNA sequencing technology can screen differentially expressed genes at different time points after spinal cord injury. Through analysis and verification, genes strongly associated with spinal cord injury can be screened. This can provide experimental data for further determining the molecular mechanism of spinal cord injury, and also provide possible targets for the treatment of spinal cord injury. This study was approved ethically by the Laboratory Animal Ethics Committee of Jiangsu Province, China(approval No. 2018-0306-001) on March 6, 2018.  相似文献   
78.
Rosacea has been reported to be associated with psychiatric disorders. Nevertheless, a nationwide study of the relationship between rosacea and comorbid psychiatric diseases in an Asian population has not been conducted. The aim of this study was to clarify the role of rosacea in the various psychiatric disorders by using a nationwide database in Taiwan. Data were obtained from the National Health Insurance Research Database of Taiwan from 2000 to 2013. In total, 7881 patients with rosacea and 31 524 age‐ and sex‐matched controls were enrolled. Patients with rosacea tended to have more coexisting psychiatric disorders. After adjusting for age, sex, comorbidity and residence/regions, the adjusted hazard ratio (HR) of psychiatric disorders for patients with rosacea was 2.761 (95% CI = 2.650–2.877, < 0.001). Among them, the highest adjusted HR are phobic disorder and obsessive–compulsive disorder of 7.841 (95% CI = 7.526–8.170, < 0.001) and 6.389 (95% CI = 6.132–6.657, < 0.001), respectively. The National Health Insurance Research Database of Taiwan does not include the information about rosacea subtypes, severity and laboratory parameters. In conclusion, rosacea is related to various psychiatric disorders. In addition to anxiety and depression, patients are also at increased risk of phobic disorder and obsessive–compulsive disorder.  相似文献   
79.
罗洋  代艺  李芬 《护理学杂志》2019,34(17):39-41
目的改进造口袋更换方法,以提高回肠造口、襻式造口和水肿造口三类特殊造口患者的维护效果。方法将行临时性或永久性肠造口术患者77例随机分为对照组39例和观察组38例。对照组采取常规方法更换造口袋,观察组采取改进方法更换造口袋,即调整涂抹防漏膏、套入造口袋和清洁皮肤的顺序。比较两组术后9 d内粪水性皮炎发生率、造口底盘渗漏率和造口袋更换用时。结果观察组术后9 d内粪水性皮炎发生率显著低于对照组,术后第3天和第6天造口底盘渗漏发生率显著低于对照组(均P0.05),但观察组术后第1天、第3天和第6天造口袋更换时间显著长于对照组(均P0.01)。结论采取改进的造口袋更换方法对特殊造口进行维护,有利于减少造口底盘渗漏,降低粪水性皮炎的发生。  相似文献   
80.
考察《伤寒杂病论》经方中配伍应用芍药的61首经方(56首原方,5首加减方)及126条相关条文。通过对经方剂量、比例、配伍、病位主症的分析,认为:经方中芍药为白芍;白芍并非补血药,其益阴补血的功效是通过配伍实现;经方中"分"为计量单位;芍药在丸散汤中的常见用量;经方中芍药主治的症状包括四肢挛急、腹痛、烦满、下利、小便不利等。与不同药物配伍,作用部位与症状随之变化,常见配伍有桂枝、附子、甘草、柴胡、黄芩、枳实、当归、茯苓等。  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