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1.
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   
2.
Cantharidin (CTD) is an effective antitumor agent. However, it exhibits significant hepatotoxicity, the mechanism of which remains unclear. In this study, biochemical and histopathological analyses complemented with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS)-based targeted metabolomic analysis of bile acids (BAs) were employed to investigate CTD-induced hepatotoxicity in rats. Sixteen male and female Sprague–Dawley rats were randomly divided into two groups: control and CTD (1.0 mg/kg) groups. Serum and liver samples were collected after 28 days of intervention. Biochemical, histopathological, and BA metabolomic analyses were performed for all samples. Further, the key biomarkers of CTD-induced hepatotoxicity were identified via multivariate and metabolic pathway analyses. In addition, metabolite–gene–enzyme network and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used to identify the signaling pathways related to CTD-induced hepatotoxicity. The results revealed significantly increased levels of biochemical indices (alanine aminotransferase, aspartate aminotransferase, and total bile acid). Histopathological analysis revealed that the hepatocytes were damaged. Further, 20 endogenous BAs were quantitated via UHPLC-MS/MS, and multivariate and metabolic pathway analyses of BAs revealed that hyocholic acid, cholic acid, and chenodeoxycholic acid were the key biomarkers of CTD-induced hepatotoxicity. Meanwhile, primary and secondary BA biosynthesis and taurine and hypotaurine metabolism were found to be associated with the mechanism by which CTD induced hepatotoxicity in rats. This study provides useful insights for research on the mechanism of CTD-induced hepatotoxicity.  相似文献   
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社会力量具备相应的经济基础和技术条件,对于公立互联网医院体系建设具有积极的促进作用。但是实践中仍然存在商业模式不完善、监管制度不健全等问题。基于经济学契约理论要义,提出在坚持激励与约束机制并举、平衡公私益关系的前提下,通过完善医保政策、构建互联网医疗服务价格分类管理机制来促进社会力量向医疗服务公益性目标回归,并通过构建完善的监督体制来约束部分社会力量的盲目逐利性行为。  相似文献   
5.
Zedoary tumeric (Curcumae Rhizoma, Ezhu in Chinese) has a long history of application and has great potential in the treatment of liver cancer. The anti liver cancer effect of zedoary tumeric depends on the combined action of multiple pharmacodynamic substances. In order to clarify the specific mechanism of zedoary tumeric against liver cancer, this paper first analyzes the mechanism of its single pharmacodynamic substance against liver cancer, and then verifies the joint anti liver cancer mechanism of its "pharmacodynamic group". By searching the research on the anti hepatoma effect of active components of zedoary tumeric in recent years, we found that pharmacodynamic substances, including curcumol, zedoarondiol, curcumenol, curzerenone, curdione, curcumin, germacrone, β-elemene, can act on multi-target and multi-channel to play an anti hepatoma role. For example, curcumin can regulate miR, GLO1, CD133, VEGF, YAP, LIN28B, GPR81, HCAR-1, P53 and PI3K/Akt/mTOR, HSP70/TLR4 and NF-κB. Wnt/TGF/EMT, Nrf2/Keap1, JAK/STAT and other pathways play an anti hepatoma role. Network pharmacological analysis showed that the core targets of the "pharmacodynamic group" for anti-life cancer are AKT1, EGFR, MAPK8, etc, and the core pathways are neuroactive live receiver interaction, nitrogen metabolism, HIF-1 signaling pathway, etc. At the same time, by comparing and analyzing the relationship between the specific mechanisms of pharmacodynamic substance and "pharmacodynamic group", it is found that they have great reference significance in target, pathway, biological function, determination of core pharmacodynamic components, formation of core target protein interaction, in-depth research of single pharmacodynamic substance, increasing curative effect and so on. By analyzing the internal mechanism of zedoary tumeric pharmacodynamic substance and "pharmacodynamic group" in the treatment of liver cancer, this paper intends to provide some ideas and references for the deeper pharmacological research of zedoary tumeric and the relationship between pharmacodynamic substance and "pharmacodynamic group".  相似文献   
6.
顺铂(DDP)作为第一个被发现的金属抗癌药物,是目前最有潜力和应用最广泛的抗肿瘤药物。顺铂在宫颈癌的治疗中尤为重要,目前已被推荐为同步放化疗的首选药物。但随着广泛的使用,顺铂的耐药性逐渐显露出来,并成为限制临床疗效和部分患者肿瘤治疗进展的主要原因之一。顺铂的耐药机制复杂,发生环节较多,但具体耐药机制尚不明确,目前按照顺铂耐药发生的环节可分为:①顺铂在血液循环过程中产生耐药;②顺铂通过细胞膜的流入或流出产生耐药;③顺铂在胞质中产生耐药;④顺铂与DNA结合后产生耐药。本文综述了宫颈癌顺铂耐药可能发生的四个环节及克服耐药常用的手段,为提高顺铂对宫颈癌的疗效提供依据。  相似文献   
7.
《Clinical neurophysiology》2021,132(6):1312-1320
ObjectiveTo investigate the additional value of EEG functional connectivity features, in addition to non-coupling EEG features, for outcome prediction of comatose patients after cardiac arrest.MethodsProspective, multicenter cohort study. Coherence, phase locking value, and mutual information were calculated in 19-channel EEGs at 12 h, 24 h and 48 h after cardiac arrest. Three sets of machine learning classification models were trained and validated with functional connectivity, EEG non-coupling features, and a combination of these. Neurological outcome was assessed at six months and categorized as “good” (Cerebral Performance Category [CPC] 1–2) or “poor” (CPC 3–5).ResultsWe included 594 patients (46% good outcome). A sensitivity of 51% (95% CI: 34–56%) at 100% specificity in predicting poor outcome was achieved by the best functional connectivity-based classifier at 12 h after cardiac arrest, while the best non-coupling-based model reached a sensitivity of 32% (0–54%) at 100% specificity using data at 12 h and 48 h. Combination of both sets of features achieved a sensitivity of 73% (50–77%) at 100% specificity.ConclusionFunctional connectivity measures improve EEG based prediction models for poor outcome of postanoxic coma.SignificanceFunctional connectivity features derived from early EEG hold potential to improve outcome prediction of coma after cardiac arrest.  相似文献   
8.
目的 探讨 σ度量在深圳市龙华区三家综合医院临床生化检验结果互认中的应用价值。方法 收集三家医院 2019年广东省临检中心常规化学,特殊蛋白前两次的室间质评( EQA)样本,经混匀并分割成比对样本送至各评价实验室进行检测;以卫生部临检中心( NCCL)标准和生物学变异导出的允许总误差( TEa%)为质量规范,通过加权法计算出各项目 2019年 1~ 6月期间室内质控在控数据的不精密度,以 2018年参加卫生部室间质评( EQA)数据作为偏倚( bias%)来源,计算三家医院 29个检验项目的 σ度量值并进行性能评价,利用质量目标指数( QGI)提出改善方法;将评价项目的 σ度量值与直接比对试验进行比较,通过统计分析确定 σ截断值( cut-off)。结果 ①三家医院 29个生化项目的性能并不一致,将项目中、高值的 σ值进行配对 t检验,其 t值分别为 2.28,3.01和 0.74,按 α =0.05水准判断得出医院 A与 B,医院 A与 C间的性能差异有统计学意义,医院 B与 C间的性能差异无统计学意义,医院 A项目性能要优于 B,C医院。评估的 87个项目中有 53项 σ平均值 <6,根据 QGI判断,3个项目需优先改善准确度,10个项目需同步改善准确度和精密度,另 40个项目需优先改善精密度。②对医院间项目比对通过率进行配对 χ2检验,其 χ2分别为 5.33,6.25和 2.5,按α=0.05水准判断, B与 A医院比对通过率低于 C与 A医院、 C与 B医院,差异有统计学意义; C与 A医院比对通过率跟 C与 B医院差异无统计学意义。③将 σ度量值与直接比对试验进行比较,经配对 χ2检验,当 σ cut-off值取≥ 2σ, ≥ 3σ,≥ 4σ,≥ 5σ和≥ 6σ时,其 χ2分别为 7.20,0.00,9.09,15.06和 16.06,按 χ20.05,1=3.84,α=0.05水准判断,当σcut-off值取≥ 3σ时,两种比对方法的差异无统计学意义。结论 σ度量值可以单独用于评价医院间生化检验结果的互认,在判断项目是否具有可比性时,可考虑将 σ cut-off值设为≥ 3σ。  相似文献   
9.
降尿酸是治疗痛风和高尿酸血症的基本方法,目前降尿酸作用途径主要是通过抑制黄嘌呤氧化酶、腺苷脱氨酶等合成酶的活性,或(且)影响肾脏尿酸转运蛋白(OAT1、OAT3、URAT1、GLUT9)等的表达,进而降低尿酸的水平。由于中药治疗高尿酸血症及痛风的作用机制尚不明确,因此本文通过检索中国知网、维普、万方、pubMed、Embase等数据库,对相关文献进行筛选,总结了具有明确降尿酸作用机制的单味中药,并进行功效归类,有助于对其作用机制进一步研究,为防治痛风和高尿酸血症提供更可靠、更安全的中医治疗依据。  相似文献   
10.
Motion perception is a vital part of our sensory repertoire in that it contributes to navigation, awareness of moving objects, and communication. Motion sense in carnivores and primates originates with primary visual cortical neurons selective for motion direction. More than 60 years after the discovery of these neurons, there is still no consensus on the mechanism underlying direction selectivity. This paper describes a model of the cat''s visual system in which direction selectivity results from the well-documented orientation selectivity of inhibitory neurons: inhomogeneities in the orientation preference map for inhibitory neurons leads to spatially asymmetric inhibition, and thus to direction selectivity. Stimulation of the model with a drifting grating shows that direction selectivity results from the relative timing of excitatory and inhibitory inputs to a neuron. Using a stationary contrast-reversing grating reveals that the inhibitory input is spatially displaced in the preferred direction relative to the excitatory input, and that this asymmetry leads to the timing difference. More generally, the model yields physiologically realistic estimates of the direction selectivity index, and it reproduces the critical finding with contrast-reversing gratings that response phase advances with grating spatial phase. It is concluded that a model based on intracortical inhibition can account well for the known properties of direction selectivity in carnivores and primates.SIGNIFICANCE STATEMENT Motion perception is vital for navigation, communication, and the awareness of moving objects. Motion sense depends on cortical neurons that are selective for motion direction, and this paper describes a model for the physiological mechanism underlying cortical direction selectivity. The essence of the model is that intracortical inhibition of a direction-selective cell is spatially inhomogeneous and therefore depends on whether a stimulus generates inhibition before or after reaching the cell''s receptive field: the response is weaker in the former than in the latter case. If the model is correct, it will contribute to the understanding of motion processing in carnivores and primates.  相似文献   
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