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21.
Depression and vitamin D deficiency are major public health problems. The existing literature indicates the complex relationship between depression and vitamin D. The purpose of this study was to examine whether this relationship is moderated or mediated by inflammation. A community sample (n = 7162) from the LIFE-Adult-Study was investigated, for whom depressive symptoms were assessed via the German version of CES-D scale and serum 25-hydroxyvitamin D (25(OH)D) levels and inflammatory markers (IL-6 and CRP levels, WBC count) were quantified. Mediation analyses were performed using Hayes’ PROCESS macro and regression analyses were conducted to test moderation effects. There was a significant negative correlation between CES-D and 25(OH)D, and positive associations between inflammatory markers and CES-D scores. Only WBC partially mediated the association between 25(OH)D levels and depressive symptoms both in a simple mediation model (ab: −0.0042) and a model including covariates (ab: −0.0011). None of the inflammatory markers showed a moderation effect on the association between 25(OH)D levels and depressive symptoms. This present work highlighted the complex relationship between vitamin D, depressive symptoms and inflammation. Future studies are needed to examine the effect of vitamin D supplementation on inflammation and depressive symptomatology for causality assessment.  相似文献   
22.
BackgroundSocial media has become a ubiquitous part of daily life during the COVID-19 pandemic isolation. However, the role of social media use in depression and suicidal ideation of the general public remains unclear. Related empirical studies were limited and reported inconsistent findings. Little is known about the potential underlying mechanisms that may illustrate the relationship between social media use and depression and suicidal ideation during the COVID-19 pandemic.ObjectiveThis study tested the mediation effects of social loneliness and posttraumatic stress disorder (PTSD) symptoms on the relationship between social media use and depressive symptoms and suicidal ideation, as well as the moderation effect of age on the mediation models.MethodsWe administered a population-based random telephone survey in May and June 2020, when infection control measures were being vigorously implemented in Hong Kong. A total of 1070 adults (658 social media users and 412 nonusers) completed the survey. Structural equation modeling (SEM) and multigroup SEM were conducted to test the mediation and moderation effects.ResultsThe weighted prevalence of probable depression was 11.6%; 1.6% had suicidal ideation in the past 2 weeks. Both moderated mediation models of depressive symptoms (χ262=335.3; P<.05; comparative fit index [CFI]=0.94; nonnormed fit index [NNFI]=0.92; root mean square error of approximation [RMSEA]=0.06) and suicidal ideation (χ234=50.8; P<.05; CFI=0.99; NNFI=0.99; RMSEA=0.02) showed acceptable model fit. There was a significantly negative direct effect of social media use on depressive symptoms among older people (β=–.07; P=.04) but not among younger people (β=.04; P=.55). The indirect effect via PTSD symptoms was significantly positive among both younger people (β=.09; P=.02) and older people (β=.10; P=.01). The indirect effect via social loneliness was significant among older people (β=–.01; P=.04) but not among younger people (β=.01; P=.31). The direct effect of social media use on suicidal ideation was not statistically significant in either age group (P>.05). The indirect effects via PTSD symptoms were statistically significant among younger people (β=.02; P=.04) and older people (β=.03; P=.01). Social loneliness was not a significant mediator between social media use and suicidal ideation among either age group (P>.05).ConclusionsSocial media may be a “double-edged sword” for psychosocial well-being during the COVID-19 pandemic, and its roles vary across age groups. The mediators identified in this study can be addressed by psychological interventions to prevent severe mental health problems during and after the COVID-19 pandemic.  相似文献   
23.
目的 基于HPLC指纹图谱与多成分含量测定,并结合主成分分析,评价半枝莲Scutellaria barbata的质量。方法 采用RP-HPLC法,流动相为乙腈-0.1%甲酸水溶液进行梯度洗脱,对19批人工栽培和市售半枝莲药材进行指纹图谱及4种黄酮类成分含量测定研究,应用主成分分析法对半枝莲质量进行评价。结果 建立了半枝莲药材的共有模式指纹图谱,共标定16个共有峰,半枝莲药材的相似度为0.817~0.989,野黄芩苷、野黄芩素、木犀草素、芹菜素的质量分数分别为0.015%~0.850%、0.010%~0.180%、0.00034%~0.07400%、0.0019%~0.0690%;主成分分析结果筛选出累计贡献率达到96.268%的4个主成分(野黄芩苷;野黄芩素;木犀草素;芹菜素),以它们计算所有样本的综合得分,可对半枝莲药材质量进行排序。结论 通过指纹图谱与含量测定相结合,应用主成分分析可全面综合评价半枝莲质量。此方法的建立为半枝莲药材的质量控制及评价提供了了分析方法和数据支撑。  相似文献   
24.
Objective:Using a novel mediation method that presents unbiased results even in the presence of exposure–mediator interactions, this study estimated the extent to which working conditions and health behaviors contribute to educational inequalities in self-rated health in the workforce.Methods:Respondents of the longitudinal Survey of Health, Ageing, and Retirement in Europe (SHARE) in 16 countries were selected, aged 50–64 years, in paid employment at baseline and with information on education and self-rated health (N=15 028). Education, health behaviors [including body mass index (BMI)] and working conditions were measured at baseline and self-rated health at baseline and two-year follow-up. Causal mediation analysis with inverse odds weighting was used to estimate the total effect of education on self-rated health, decomposed into a natural direct effect (NDE) and natural indirect effect (NIE).Results:Lower educated workers were more likely to perceive their health as poor than higher educated workers [relative risk (RR) 1.48, 95% confidence interval (CI) 1.37–1.60]. They were also more likely to have unfavorable working conditions and unhealthy behaviors, except for alcohol consumption. When all working conditions were included, the remaining NDE was RR 1.30 (95% CI 1.15–1.44). When BMI and health behaviors were included, the remaining NDE was RR 1.40 (95% CI 1.27–1.54). Working conditions explained 38% and health behaviors and BMI explained 16% of educational inequalities in health. Including all mediators explained 64% of educational inequalities in self-rated health.Conclusions:Working conditions and health behaviors explain over half of the educational inequalities in self-rated health. To reduce health inequalities, improving working conditions seems to be more important than introducing health promotion programs in the workforce.  相似文献   
25.
目的:研制一款基于体表心电、膈肌电和胸阻抗信号的呼吸功能监测仪原理样机,可在家庭、医疗急救等场合实现对呼吸功能的持续监测。方法:以STM32F411VET6单片机开发系统为平台,用一对Ag/AgCl电极作为高频激励信号的输出和心电、胸阻抗信号的检测电极,另一对Ag/AgCl电极作为膈肌电信号检测电极,两对电极同时检测心电、膈肌电和胸阻抗信号。系统硬件主要包括心电信号检测电路、胸阻抗信号检测电路、膈肌电信号检测电路、恒流源激励电路以及微控制器。系统采用12 V可充电锂电池供电,模拟信号通过单片机A/D转换成数字信号,通过SDIO接口存储于SD卡。在完成样机制作和性能测试之后,采集13例因呼吸功能障碍实施机械通气患者和13例健康成年人的信号,计算15个与呼吸功能相关的参数,比较机械通气患者与健康对照组参数之间的差异,验证了呼吸功能监测仪的可靠性。结果:样机采集信号的信噪比>10 dB、共模抑制比>80 dB,样机漏电流<30μA。机械通气患者的吸气时间、呼气时间、潮气量、胸阻抗峰峰值、胸阻抗1 s变化量、膈肌电低频功率、膈肌电高频功率、高频比低频、膈肌放电面积、膈肌放电时...  相似文献   
26.
This study was designed to investigate the effect of divided administration of edrophonium on the course of neuromuscular recovery from a pipecuronium neuromuscular blockade. During thiopentone-nitrous oxide-halothane anaesthesia 48 patients were given pipecuronium 70 micrograms.kg-1. Patients were randomly assigned to one of four groups (n = 12 in each) to receive either edrophonium 1 mg.kg-1 (Groups I and II) or edrophonium 0.75 mg.kg-1 (Groups III and IV). In Groups I and III (single-dose groups), edrophonium was administered as a single bolus dose. In Groups II and IV (divided-dose groups) edrophonium was administered as an initial dose of 0.25 mg.kg-1 followed three minutes later by either 0.75 or 0.50 mg.kg-1 respectively. Reversal was attempted at 20% spontaneous recovery of twitch height. Administration of edrophonium in divided doses (Groups II and IV) accelerated the reversal of the pipecuronium neuromuscular blockade. At ten minutes post-reversal, train-of-four (TOF) ratio recovery reached 0.75 or more in 12 (100%) and in ten (83%) patients in Groups II and IV respectively. Similarly, times to attain a TOF of 0.75 (SEM) were shorter in the divided-dose groups than in the single-dose groups (P less than 0.05), being 354.5 (38.7) and 398.3 (49.1) sec in Groups II and IV vs 705.4 (66.6) and 651.2 (54.3) sec in Groups I and III respectively. Time was counted from the first administration of edrophonium. It is concluded that administration of edrophonium in divided doses produced a faster reversal of residual pipecuronium-induced neuromuscular blockade than single bolus administration. Also, administration in divided doses reduced the requirements of edrophonium needed for reversal of pipecuronium neuromuscular blockade.  相似文献   
27.
调补气血针法对SAMP10脑中枢神经递质含量影响的研究   总被引:2,自引:0,他引:2  
目的 :旨在揭示调补气血针法治疗痴呆的中枢作用机制。方法 :采用HPLC -ECD法对SAMP10及SAMR1脑组织单胺类神经递质和乙酰胆碱 (Ach)含量进行测定。结果 :①SAMP10脑组织DA、5 -HT、Ach的含量显著低于SAMR1的含量 ;②调补气血针法可使脑组织降低的DA、5 -HT、Ach的含量显著提高。结论 :①SAMP10小鼠的学习、记忆障碍发病机制之一可能是脑组织Ach和单胺类神经递质的代谢异常出现了神经损害 ;②调补气血针法改善了SAMP10的学习、记忆状况  相似文献   
28.
浅谈历代医家对温病病因和发病的认识   总被引:2,自引:0,他引:2  
作者对自《内经》到《温热论》时期温热病的病因和发病的认识进行了总结。此由最初的以“伤寒”总称各种热病,逐步发展至“外感六淫化火说”、“非时之气,戾气说”、“伏邪之说”、“新感学说”,至清代产生了“温热毒邪学说”,从病因和发病上根本区别了温病与伤寒,同时创立了卫气营血辨证、三焦辨证等理论,形成了《温热论》。  相似文献   
29.
中医药治疗恶性肿瘤的研究进展   总被引:1,自引:0,他引:1  
阐述了中医对恶性肿瘤病因病机的认识及治则治法,对目前中医药治疗恶性肿瘤的几种新思路进行了探讨.在指出中医药治疗恶性肿瘤中存在的问题的同时,提出了笔者的几点建议。  相似文献   
30.
试论当代中医治疗乙型肝炎的基本原则   总被引:8,自引:0,他引:8  
陈立华 《中医杂志》2004,45(12):883-885,896
作为难治性疾病之一的病毒性乙型肝炎(简称乙肝),在临床运用中医中药治疗的过程中,必须严格遵循师古不泥古,开拓创新的原则.抗病毒原则、重视客观检测的原则、临床再探索的原则、辨病与辨证统一的原则以及重视药物毒性须慎重择药的原则等.  相似文献   
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