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71.
非核苷类逆转录酶抑制剂奈韦拉平   总被引:11,自引:0,他引:11  
艾滋病是严重威胁人类健康的传染性疾病,它是由HIV引发,特别是HIV-1。奈韦拉平是一种新型的非核苷类逆转录酶抑制剂,该药与核苷类逆转录酶抑制剂或蛋白酶抑制剂合用可用于治疗艾滋病,单独用药可用于预防HIV感染和母婴传播。  相似文献   
72.
73.
骨髓增生异常综合征(MDS)是克隆性造血干细胞疾病,临床表现呈现多样性和异质性,以血细胞减少为特征,少数有进展为急性白血病的危险。近十年出现了多种新的治疗方案,本文综述近年上市的以及目前处于临床研究阶段的治疗MDS的新药开发进展。  相似文献   
74.
陈航 《海峡药学》2011,23(11):220-222
目的 考察合成的向日葵胰蛋白酶抑制剂的抑制效果,计算其抑制常数Ki.方法 采用Fmoc固相化学合成方法,反相柱纯化后用CytofluorTM微孔板发光检测仪测定向日葵胰蛋白酶抑制剂的抑制常数.结果与结论 向日葵胰蛋白酶抑制剂的Ki值为2.2nM±0.5(n=8),抑制效果良好.  相似文献   
75.
子宫内膜异位症患者腹腔液中MMP-1和TIMP-1的检测   总被引:2,自引:0,他引:2  
目的 探讨腹腔液中基质金属蛋白酶1(MMP-1)及其组织抑制剂(TIMP-1)在子宫内膜异位症(EM)发病机制中的作用.方法 双抗体夹心酶联免疫吸附法定量检测44例EM患者(Ⅰ期8例、Ⅱ期2例、Ⅲ期20例、Ⅳ期14例)和30例对照组患者腹腔液中MMP-1、TIMP-1水平.结果 EM患者腹腔液中MMP-1的水平高于对照组(P<0.05),TIMP-1的水平低于对照组(P<0.01),Ⅰ~Ⅱ期腹腔液TIMP-1水平高于Ⅲ~Ⅳ期(P<0.05);对照组腹腔液MMP-1水平与TIMP-1水平呈直线正相关关系;r-AFS分期与腹腔液TIMP-1水平呈负相关关系.结论 腹腔液中MMP-1和TIMP-1可能参与了EM的发生、发展.  相似文献   
76.
Abstract

Surfactin, a natural lipopeptide produced by Bacillus, is gaining attention for potentially biomedical and pharmaceutical applications. Here, surfactin was assayed for oral delivery of insulin (INS) by its ability to bind to and promote protein to penetrate through the cell membrane. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, surfactin was found to form co-precipitates with INS to protect it from acidic and enzymatic attack in the gastrointestinal tract. Further analysis by non-reductive electrophoresis showed surfactin could bind to INS forming heteropolymers. Analysis with circular dichroism, we found this binding significantly influenced the INS structure with decreased rigid α-helix and β-turn, but with increased flexible β-sheet and random coil. The change with more flexible structure was favorable for INS to penetrate through the cell membrane. Fluorescence spectra analysis also showed surfactin could lead Phe and Tyr in the inner of INS exposed outside, further promoting INS permeabilization by improving the hydrophobic-lipophilic interactions between INS and cell membrane. As a result, the effective permeability (Peff) of INS plus surfactin was 4.3 times of that of INS alone. In vivo assay showed oral INS with surfactin displayed excellent hypoglycemic effects with a relative bioavailability of 12.48% and 5.97% in diabetic mice and non-diabetic dogs, respectively. Summary, surfactin is potential for oral delivery of INS by its role as an effective protease inhibitor and permeability enhancer.  相似文献   
77.
Aim: The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is an ongoing debate and novel data has emerged. The aim of this meta-analysis was to assess outcomes of short vs. control DAPT duration. In addition, the role of single antiplatelet therapy (SAPT) after DAPT with either aspirin or P2Y12 inhibitor monotherapy was analyzed. Methods: The authors searched MEDLINE and Cochrane databases and proceedings of international meetings for randomized controlled trials (RCT) comparing ≤ 3 months with ≥ 6 months DAPT after DES implantation. The primary and co-primary outcomes of interest were definite or probable stent thrombosis (ST) and bleeding. In addition, we performed an analysis on studies who continued with either aspirin or P2Y12 monotherapy after DAPT. Results: 9 RCTs comprising 41,864 patients were included and we analyzed a short DAPT duration of median 1.5 months vs. 12.1 months in the control group. The risk for ST was similar with short vs. control DAPT duration (0.5 vs. 0.5%; hazard ratio 1.17[95% CI 0.89-1.54];p=0.26). Bleeding was significantly reduced with short vs. control DAPT duration (1.9 vs. 3.0%; 0.65[0.54-0.77];p<0.0001). ST was not different between short vs. control DAPT duration in the analysis of the 4 RCTs who continued with aspirin after DAPT and the 5 P2Y12 RCTs, respectively, and no heterogeneity was detected (p=0.861). Bleeding was also reduced with short vs. control DAPT in both the aspirin (1.2 vs. 1.7%; 0.71[0.51-0.99];p=0.04) and P2Y12 inhibitor studies (2.1 vs. 3.4%; 0.62[0.47-0.80];p=0.0003) and no heterogeneity was detected (p=0.515). Conclusions: Our meta-analysis shows that short DAPT ≤ 3 months followed by SAPT reduces bleeding and is not associated with an increase in ST. The results were consistent within the aspirin and P2Y12 SAPT studies.  相似文献   
78.
BackgroundEpidermal growth factor receptor tyrosine kinases inhibitors (EGFR-TKIs) are currently recognized as the standard treatment for advanced non-small cell lung cancer (NSCLC) patients with EGFR mutations. Clinically found patients with different EGFR mutational status have different prognosis.MethodsA retrospective cohort study was performed to explore the relationship between EGFR mutations and abundance with patient survival by using patient data from the Affiliated Cancer Hospital of Zhengzhou University between January 2013 and November 2016. All patients involved in the present study had sensitive EGFR mutations [either exon 19 deletion (DEL) or exon 21 L858R] and treated by EGFR-TKIs. They were followed up every three months until lost or dead. Mutation abundance was calculated as the copies of EGFR mutation divided by copies of EGFR locus, and the cut-off values for 19DEL and L858R were 4.9% and 9.5%, respectively.ResultsTotal of 236 patients were included, comprising 116 (49.2%) patients with 19DEL mutation and 120 (50.8%) patients with L858R mutation. The median follow-up duration was 23.2 months (95% CI: 14.9–26.7 months). Overall survival (OS) was significantly longer in patients with 19DEL mutation (20.9 months, 95% CI: 17.7–24.1 months versus 17.0 months, 95% CI: 14.4–19.6 months in patients with L858R; P=0.008) and in patients with high mutation abundance (20.9 months, 95% CI: 18.3–23.5 months versus 13.0 months, 95% CI: 10.3–15.7 months in patients with low mutation abundance; P<0.001). Multivariate Cox regression including age, performance status and tumor stage revealed that longer OS was independently associated with 19DEL mutation (HR: 0.48, 95% CI: 0.39–0.67, P=0.033) and high mutation abundance (HR: 0.62, 95% CI: 0.50–0.79, P=0.027).ConclusionsEGFR mutation types and abundance was associated with the patients’ survival which might be used to predict the efficacy of targeted therapy by EGFR-TKIs.  相似文献   
79.
Background:The 2020 European Society of Cardiology guidelines do not recommend pretreatment for nonST-segment elevation myocardial infarction (NSTEMI) patients with unclear coronary anatomy, which is inconsistent with our routine preoperative approach to loading P2Y12 receptor inhibitors (e.g., preoperative loading of 300 mg of clopidogrel).Objectives:The purpose of our study was to compare the safety and effectiveness of P2Y12 inhibitors administered before coronary angiography or at least before percutaneous coronary intervention (PCI) with during or after PCI.Methods:Cochrane, PubMed, and Embase databases were searched. The primary effect endpoint and safety endpoint were any-cause death and major bleeding, respectively. Major adverse cardiovascular events, myocardial infarction and revascularization were also analyzed.Results:Our search identified 9 trials. P2Y12 inhibitor pretreatment was associated with lower death from any cause (OR 0.62, 95% CI 0.53–0.72, P < 0.00001) without increasing the risk of bleeding (OR 1.02, 95% CI 0.80–1.30, P = 0.89). However, prasugrel or ticagrelor pretreatment was not associated with a lower risk of mortality (OR 0.70, 95% CI 0.31–1.59, P = 0.40) and increased the risk of bleeding (OR 1.67, 95% CI 1.10–2.54, P = 0.02).Conclusions:In summary, clopidogrel pretreatment was associated with significantly lower mortality, major adverse cardiovascular events, myocardial infarction and revascularization with no increase in major bleeding. However, these advantages were not observed with prasugrel or ticagrelor pretreatment.  相似文献   
80.
Single nucleotide polymorphisms (SNPs) of tissue inhibitor of metalloproteinases-3 (TIMP-3) have been revealed to be related to various cancers. To date, no study explores the relationships between TIMP-3 polymorphisms and uterine cervical cancer. The purposes of this research were to investigate the associations among genetic variants of TIMP-3 and development and clinicopathological factors of uterine cervical cancer, and patient 5 years survival in Taiwanese women. The study included 123 patients with invasive cancer and 97 with precancerous lesions of uterine cervix, and 300 control women. TIMP-3 polymorphisms rs9619311, rs9862 and rs11547635 were checked and their genotypic distributions were determined by real-time polymerase chain reaction. It showed that women with genotypes CT/TT in rs9862 were found to display a higher risk of developing cervical cancer with moderate and poor cell differentiation. Moreover, it revealed that cervical cancer patients carrying genotypes CC in rs9619311 exhibited a poorer 5 years survival, as compared to those with TT/TC in Taiwanese women, using univariate analysis. In addition, pelvic lymph node metastasis was determined to independently predict 5 years survival in cervical cancer patients using multivariate analysis. Conclusively, TIMP-3 SNPs polymorphisms rs9619311 are related to cervical patient survival in Taiwanese women.  相似文献   
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