首页 | 官方网站   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   17238篇
  免费   1968篇
  国内免费   691篇
医药卫生   19897篇
  2024年   128篇
  2023年   675篇
  2022年   1077篇
  2021年   1686篇
  2020年   1313篇
  2019年   987篇
  2018年   800篇
  2017年   622篇
  2016年   639篇
  2015年   698篇
  2014年   1246篇
  2013年   1148篇
  2012年   988篇
  2011年   1125篇
  2010年   903篇
  2009年   813篇
  2008年   951篇
  2007年   804篇
  2006年   607篇
  2005年   451篇
  2004年   321篇
  2003年   255篇
  2002年   188篇
  2001年   127篇
  2000年   123篇
  1999年   120篇
  1998年   111篇
  1997年   115篇
  1996年   88篇
  1995年   80篇
  1994年   73篇
  1993年   64篇
  1992年   47篇
  1991年   43篇
  1990年   38篇
  1989年   40篇
  1988年   37篇
  1987年   24篇
  1986年   30篇
  1985年   35篇
  1984年   33篇
  1983年   18篇
  1982年   38篇
  1981年   23篇
  1980年   29篇
  1979年   30篇
  1978年   18篇
  1977年   20篇
  1976年   20篇
  1975年   12篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
目的 运用网络药理学方法及分子对接技术探讨黄芪干预腹膜纤维化的可能机制。方法 利用中药系统药理学数据库及分析平台(TCMSP)检索黄芪的主要化学成分及靶点,并补充文献报道相关药理作用的成分作为潜在活性成分。以"peritoneal fibrosis"为关键词分别在OMIM、Genecards获取目前已知的与腹膜纤维化相关的疾病靶点,后取两者的交集靶点;对交集基因通过STRING数据库与Cytoscape 3.7.2软件构建"药物-成分-靶点-疾病"网络及蛋白互作(PPI)网络并筛选核心网络。基于R软件使用Bioconductor生物信息软件对核心靶点进行GO及KEGG富集分析,最终采用AutoDock软件将主要有效成分与核心靶点进行分子对接,得出其结合能力。结果 筛选出20个黄芪活性成分及文献报道有相关药理作用4个, 457药物作用靶点,与674个腹膜纤维化病靶点取交集,得到86个共同靶点。GO功能富集分析提示黄芪拮抗腹膜纤维化主要参与了蛋白激酶B信号转导的调节、细胞对化学的应激反应、炎症反应的调节等通路; KEGG通路富集分析主要涉及调控肿瘤、磷脂酰肌醇-3-羟激酶-蛋白激酶B(PI3K-Akt)、晚期糖基化终末产物/晚期糖基化终末产物受体(AGE-RAGE)、人类巨细胞病毒感染、HIF-1信号通路等;分子对接结果显示关键靶点与活性成分具有较好的结合能力。结论 黄芪治疗腹膜纤维化的分子机制,可能与抑制炎症及氧化应激反应、调节多种信号通路等相关。  相似文献   
4.
随着社会的发展,人类生活方式的改变,高血压病越来越高发,具有低龄化趋势,代谢综合征常伴随发生,此种情况下的高血压往往是以舒张压升高为主,临床表现常与“亚健康”状态混淆,未能引起患者甚至部分医生的重视,然而事实上越来越多的科学研究证实舒张压高之危害十分明显,不容忽视。尽管现代医学对舒张压高的病因及病理机制有明确的阐述,但是暂时没有特效的药物。李延教授在治疗高血压病方面有着丰富的临床经验,临床中运用泽泻汤合温胆汤加减治疗舒张压高之眩晕,切中病机,加减灵活,屡有良效。文中从中医角度阐述舒张压高的病因病机,介绍李师辨病辨证思路,组方用药特点,附三则典型验案,另加个人心得体会,以期为舒张压高的有效治疗提供思路。  相似文献   
5.
It is well recognized that the world population is ageing rapidly. Therefore, it is important to understand ageing processes at the cellular and molecular levels to predict the onset of age‐related diseases and prevent them. Recent research has focused on the identification of ageing biomarkers, including those associated with the properties of the Golgi apparatus. In this context, Golgi‐mediated glycosylation of proteins has been well characterized. Additionally, other studies show that the secretion of many compounds, including pro‐inflammatory cytokines and extracellular matrix–degrading enzymes, is modified during ageing, resulting in physical and functional skin degradation. Since the Golgi apparatus is a central organelle of the secretory pathway, we investigated its structural organization in senescent primary human dermal fibroblasts using confocal and electron microscopy. In addition, we monitored the expression of Golgi‐related genes in the same cells. Our data showed a marked alteration in the Golgi morphology during replicative senescence. In contrast to its small and compact structure in non‐senescent cells, the Golgi apparatus exhibited a large and expanded morphology in senescent fibroblasts. Our data also demonstrated that the expression of many genes related to Golgi structural integrity and function was significantly modified in senescent cells, suggesting a relationship between Golgi apparatus function and ageing.  相似文献   
6.
正目前,临床上对于直肠癌常用的影像评估方法有MRI、螺旋CT、PET-CT、直肠腔内超声(ERUS)等。而MRI作为首选检查方式,对肿瘤位置、浸润深度、淋巴结转移、血管侵犯、环周切缘及周围器官侵犯等方面的评估均具有明显优势~([1-2])。通过MRI诊断淋巴结的方法通常是影像科医师逐层浏览每一幅图像,从中识别淋巴结的形状、界限及密度来判断,这种传统方式耗时较长且存在主观偏倚,导致  相似文献   
7.

Background

It has been reported that particulate matter (PM) is associated with cardiovascular diseases (CVD) while metabolic syndrome is also an important risk factor for CVD. However, few studies have investigated the epidemiological association between PM and metabolic syndrome.

Objective

To investigate the association between one-year exposure to PM with an aerodynamic diameter <2.5?μm (PM2.5) and the risk of metabolic syndrome in Korean adults without CVD.

Methods

Exposure to PM2.5 was assessed using a Community Multiscale Air Quality (CMAQ) model. Metabolic syndrome was defined by National Cholesterol Education Program Adult Treatment Panel III. Andersen and Gill model with time-varying covariates, considering recurrent events, was used to investigate the association between one-year average PM2.5 and the risk of incident metabolic syndrome in 119,998 adults from the national health screening cohort provided by Korea National Health Insurance from 2009 to 2013.

Results

Higher risk of metabolic syndrome, waist-based obesity, hypertension, hypertriglyceridemia, low HDL cholesterol, and hyperglycemia were significantly associated with a 10-μg/m3 increase in PM2.5 [adjusted hazard ratio (HR): 1.070, 1.510, 1.499, 1.468, 1.627 and 1.380, respectively]. In addition, the risk of metabolic syndrome associated with PM2.5 exposure was significant in the consistently obese group (obese at baseline and endpoint).

Conclusion

Exposure to one-year average PM2.5 is associated with an increased risk of metabolic syndrome and its components in adults without CVD. These associations are particularly prominent in the consistently obese group (obese at baseline and endpoint). Our findings indicate that PM2.5 affects the onset of MS and its components which may lead to increase the risk of CVD.  相似文献   
8.
BackgroundMetabolic syndrome (MetS) is related to the increased risk of major cardiovascular diseases (CVD). The link between high serum total bilirubin (TBL) is cross-sectionally related to MetS and its components. However, whether serum TBL predicts incidence of MetS and its components remains inconclusive.MethodsThe present study included 893 women aged 70 ± 9 years from a rural village. We examined the relationship between serum TBL and MetS based on the modified criteria of the National Cholesterol Education Program's Adult Treatment Panel (NCEP-ATP) III report in a cross-sectional (N = 893) and cohort (N = 288) data.ResultsIn the cross-sectional study, serum TBL (β = 0.536, p < 0.001) as well as age, alcohol consumption, exercise habits, history of CVD, SUA, GGT, and ALT was significantly and dependently associated with number of MetS components, but in the cohort study serum TBL was not associated with number of MetS components. Compared with the 1st tertile of serum TBL (0.20–0.55 mg/dL), multivariate-adjusted odds ratio (95% confidence interval) for the 2nd -3rd tertiles of serum TBL (0.54–2.00 mg/dL) was 0.70 (0.51–0.95) in the cross-sectional study and 0.41 (0.21–0.81) in the cohort study.ConclusionsOur data demonstrated an independently negative association between serum TBL and MetS in Japanese community-dwelling women.  相似文献   
9.
《Brain stimulation》2022,15(2):337-351
BackgroundAbnormalities in frontoparietal network (FPN) were observed in many neuropsychiatric diseases including substance use disorders. A growing number of studies are using dual-site-tACS with frontoparietal synchronization to engage this network. However, a computational pathway to inform and optimize parameter space for frontoparietal synchronization is still lacking. In this case study, in a group of participants with methamphetamine use disorders, we proposed a computational pathway to extract optimal electrode montage while accounting for stimulation intensity using structural and functional MRI.MethodsSixty methamphetamine users completed an fMRI drug cue-reactivity task. Four main steps were taken to define electrode montage and adjust stimulation intensity using 4x1 high-definition (HD) electrodes for a dual-site-tACS; (1) Frontal seed was defined based on the maximum electric fields (EF) predicted by simulation of HD montage over DLPFC (F3/F4 in EEG 10–10), (2) frontal seed-to-whole brain context-dependent correlation was calculated to determine connected regions to frontal seeds, (3) center of connected cluster in parietal cortex was selected as a location for placing the second set of HD electrodes to shape the informed montage, (4) individualized head models were used to determine optimal stimulation intensity considering underlying brain structure. The informed montage was compared to montages with large electrodes and classic frontoparietal HD montages (F3-P3/F4-P4) in terms of tACS-induced EF and ROI-to-ROI task-based/resting-state connectivity.ResultsCompared to the large electrodes, HD frontoparietal montages allow for a finer control of the spatial peak fields in the main nodes of the FPN at the cost of lower maximum EF (large-pad/HD: max EF[V/m] = 0.37/0.11, number of cortical sub-regions that EF exceeds 50% of the max = 77/13). For defining stimulation targets based on EF patterns, using group-level head models compared to a single standard head model results in comparable but significantly different seed locations (6.43 mm Euclidean distance between the locations of the frontal maximum EF in standard-space). As expected, significant task-based/resting-state connections were only found between frontal-parietal locations in the informed montage. Cue-induced craving score was correlated with frontoparietal connectivity only in the informed montage (r = ?0.24). Stimulation intensity in the informed montage, and not in the classic HD montage, needs 40% reduction in the parietal site to reduce the disparity in EF between stimulation sites.ConclusionThis study provides some empirical insights to montage and dose selection in dual-site-tACS using individual brain structures and functions and proposes a computational pathway to use head models and functional MRI to define (1) optimum electrode montage for targeting FPN in a context of interest (drug-cue-reactivity) and (2) proper transcranial stimulation intensity.  相似文献   
10.
目的:采用网状Meta分析方法,将普萘洛尔联合其他治疗与各对照治疗措施进行对比。方法:以“普萘洛尔”,“血管瘤”为关键词检索CNKI、VIP、万方数据;以“propranolol”“hemangioma”为关键词检索Cochrane Library、Embase、pubmed。检索期限为建库至2019年6月1日。采用STATA14.0软件Network程序包进行数据分析。结果:共纳入18篇文献,涉及8项治疗措施,共纳入1469例血管瘤患者。网状Meta分析结果显示:4种联合治疗方式与单纯口服普萘洛尔相比疗效均优于单纯口服普萘洛尔治疗。普萘洛尔联合注射平阳霉素、普萘洛尔联合外用噻吗洛尔、普萘洛尔联合敷贴器的有效率均优于对应的注射平阳霉素、外用噻吗洛尔及敷贴器。各治疗措施的有效性排序为:普萘洛尔联合敷贴器>普萘洛尔联合外用噻吗洛尔>普萘洛尔联合口服糖皮质激素>普萘洛尔联合注射平阳霉素>敷贴器照射>外用噻吗洛尔>口服普萘洛尔>注射平阳霉素。结论:对于婴幼儿血管瘤的治疗,普萘洛尔联合治疗措施疗效均优于单纯的口服普萘洛尔治疗,其中普萘洛尔联合敷贴器的疗效最佳。  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-23

京公网安备 11010802026262号