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31.
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   
32.
Elevated serum uric acid (SUA) levels have been associated with several cardiovascular risk factors and the progression of coronary artery disease. In the setting of acute myocardial infarction, increasing evidence suggests that high SUA levels could be related to adverse outcomes. Interestingly elevated SUA levels have been linked to endothelial dysfunction, inflammation and oxidative stress. The aim of this review is to discuss the potential negative effects of SUA in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention, analyzing the possible underlying pathophysiological mechanisms.  相似文献   
33.
《Drug discovery today》2022,27(6):1733-1742
Compounds that exhibit assay interference or undesirable mechanisms of bioactivity are routinely encountered in assays at various stages of drug discovery. We observed that assays for the investigation of thiol-reactive and redox-active compounds have not been collected in a comprehensive review. Here, we review these assays and subject them to experimental optimization to improve their reliability. We demonstrate the usefulness of our assay cascade by assaying a library of bioactive compounds, chemical probes, and a set of approved drugs. These high-throughput assays should complement the array of wet-lab and in silico assays during the initial stages of hit discovery campaigns to pursue only hit compounds with tractable mechanisms of action.  相似文献   
34.
电离辐射会对人体造成损伤,根据受照剂量、时间等因素的不同可诱发多种生物效应。目前对于低剂量辐射产生的健康效应仍有争议,筛选对低剂量敏感的辐射响应生物标志物,对于完善低剂量辐射生物效应机制、拓宽低剂量辐射在临床中的应用均具有重要理论意义。综述探讨各核糖核酸(RNA)在低剂量辐射反应中的变化及其对辐射敏感性的调节作用,同时评估各RNA作为低剂量辐射响应标志物的潜力。  相似文献   
35.
目的 建立细叶亚菊的质量标准,为其质量控制和合理开发利用提供科学参考。方法 采用性状鉴别、显微鉴别、薄层色谱法(TLC)对细叶亚菊进行定性分析;参照《中国药典》(2020年版)通则方法对细叶亚菊水分、总灰分、酸不溶性灰分、水溶性浸出物进行含量检查;利用高效液相色谱法(HPLC)测定细叶亚菊中绿原酸、异绿原酸A的含量。结果 确定了细叶亚菊的药材性状及显微特征。TLC鉴别显示,供试品(细叶亚菊药材)与对照品(绿原酸、异绿原酸A)在相应位置上均显示相同颜色的荧光斑点。13批细叶亚菊水分、总灰分、酸不溶性灰分、浸出物的含量分别为8.55%-13.07%、6.81%-12.68%、1.11%-3.53%、8.41%-11.64%;绿原酸、异绿原酸A的含量范围分别为0.072%-0.440%、0.283%-1.324%(n=3)。结论 本研究建立的方法准确稳定,可为细叶亚菊的质量控制提供参考。暂规定细叶亚菊水分不得过12.0%,总灰分不得过10.0%,酸不溶性灰分不得过2.5%,水溶性浸出物不得少于8.0%,绿原酸不得少于0.2%,异绿原酸A不得少于0.6%。  相似文献   
36.
Matrix metalloproteinase-11 (MMP11) is an enzyme with proteolytic activity against matrix and nonmatrix proteins. Although most MMPs are secreted as inactive proenzymes and are later activated extracellularly, MMP11 is activated intracellularly by furin within the constitutive secretory pathway. It is a key factor in physiological tissue remodeling and its alteration may play an important role in the progression of epithelial malignancies and other diseases. TCGA colon and colorectal adenocarcinoma data showed that upregulation of MMP11 expression correlates with tumorigenesis and malignancy. Here, we provide evidence that a germline variant in the MMP11 gene (NM_005940: c.232C>T; p.(Pro78Ser)), identified by whole exome sequencing, can increase the tumorigenic properties of colorectal cancer (CRC) cells. P78S is located in the prodomain region, which is responsible for blocking MMP11's protease activity. This variant was detected in the proband and all the cancer-affected family members analyzed, while it was not detected in healthy relatives. In silico analyses predict that P78S could have an impact on the activation of the enzyme. Furthermore, our in vitro analyses show that the expression of P78S in HCT116 cells increases tumor cell invasion and proliferation. In summary, our results show that this variant could modify the structure of the MMP11 prodomain, producing a premature or uncontrolled activation of the enzyme that may contribute to an early CRC onset in these patients. The study of this gene in other CRC cases will provide further information about its role in CRC development, which might improve patient treatment in the future.  相似文献   
37.
IntroductionRapid diagnostic tests have been developed recently for rapid species or resistance genes identification, offering the potential to improve the selection of appropriate antibiotics. The newly developed FilmArray Blood Culture Identification 2 (BCID2) panel, which can identify more species and resistance genes, such as extended-spectrum beta-lactamase, is expected to make an impact on antimicrobial practice.MethodsThe consecutive 50 inpatients with Gram-negative bacilli bacteremia were enrolled to this retrospective single-center study. In addition to the existing FilmArray Blood Culture Identification (BCID) panel, we have implemented BCID2 panel for positive blood culture. The sensitivity and specificity of BCID and BCID2 panel were respectively calculated, and a simulation study of time to effective, optimal and de-escalation therapy was performed based on BCID or BCID2 result.ResultsA total of 52 Gram-negative organisms in 50 patients were identified from blood cultures. Of these, 45 (87%) organisms were detected by BCID2 panel, which was more than BCID panel (41 organisms, 79%). BCID2 panel detected 5 CTX-M genes, which were concordant with conventional method. The time to effective therapy did not differ between BCID arm and BCID2 arm; however, the median time to optimal therapy (34 h in BCID arm and 26 h in BCID2 arm, P = 0.0007) and the median time to de-escalation therapy (42 h in BCID arm and 22 h in BCID2 arm, P = 0.0005) were significantly shortened.ConclusionsThis simulation study of BCID2 panel showed high sensitivity and specificity, and the potential impact on shortening the time to optimal and de-escalation therapy.  相似文献   
38.
39.
目的:评价注射用核糖核酸Ⅱ联合化疗在真实世界中治疗晚期胰腺癌的疗效和安全性。方法:基于LinkDoc数据库纳入2012年至2018年就诊于河南省肿瘤医院等10家研究中心且确诊为局部进展期和晚期胰腺癌的患者923例,试验组采用化疗联合注射用核糖核酸Ⅱ治疗,对照组采用单纯化疗治疗。采用倾向性评分匹配的方法均衡两组的基线信息,比较两组间的总生存期(overall survival,OS)、无进展生存期(progression-free survival,PFS)及不良事件和化疗相关不良反应的发生率。结果:试验组和对照组的中位OS分别为7.5个月和6.7个月,中位PFS分别为3.7个月和3.3个月,差异均无统计学意义(P>0.05)。试验组不良事件发生率略低于对照组(88.7%vs 92.1%),试验组化疗相关不良反应发生率略高于对照组(64.1%vs 57.1%),差异均无统计学意义(P>0.05)。结论:注射用核糖核酸Ⅱ联合化疗治疗晚期胰腺癌具有生存获益趋势,无肝转移患者是潜在的优势人群,该结论尚需前瞻性研究进一步确证。  相似文献   
40.
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