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991.
Even though Arcobacter butzleri has been implicated in some human disease as diarrhoea and bacteraemia, much of its pathogenesis and virulence factors remain unclear.In this work we have compared pathogenic and genotypic properties of six A. butzleri isolates from human and non-human sources. The tested isolates showed to be susceptible to tetracyclines and aminoglycosides, however non-human isolates were all resistant to quinolones. The ability to form biofilms was variable among the tested strains, and all of them showed a weak haemolytic activity. The presence of nine putative virulence genes was determined, with cadF, ciaB, cj1349, mviN, pldA, tlyA being detected in all strains, while irgA (3/6), hecA (5/6), hecB (4/6) were detected only in some strains. High levels of adhesion were observed for A. butzleri on Caco-2 cells, with pre-existing inflammation showing no significant effect on the adherence ability; yet variable levels of invasion were observed. A. butzleri isolates were able to survive intracellularly in Caco-2 cells and to induce a significant up-regulation of interleukin-8 secretion and structural cell rearrangements. These data brings new insights on A. butzleri virulence and highlights its pathogenic potential.  相似文献   
992.
993.
Redox‐active polymers became the focus of attention in the field of organic electronics during the last decade. Quinoide systems are intensively studied in this field. Although benzoquinones are generally known as radical scavengers, certain monomers can be polymerized by radical polymerization techniques. For this purpose, methacrylate functionalities are attached to the redox‐active quinone moiety. A free‐radical polymerization technique is applied utilizing AIBN as initiator. The molar mass can be adjusted by the choice of an appropriate solvent system. Electrochemical investigations of these new monomers and polymers, in particular cyclic voltammetry, are performed in aqueous and non‐aqueous electrolytes in the dissolved and solid states, showing the potential usefulness of the system for applications in organic radical batteries.

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994.
11h is a very potent inhibitor against epidermal growth factor receptor triple mutation L858R/T790M/C797S (EGFRTM) with 13‐fold stronger potency than the FDA‐approved osimertinib. Recently, two new EGFRTM inhibitors, 11d and 11e , were reported which revealed 2.8‐ and 2.3‐fold stronger potency than 11h , respectively. 11h , 11d, and 11e have the same structures but differ only in their aliphatic chain length. However, the exact effects of differential aliphatic chain length on the inhibitory potencies of these compounds require further elaboration at the atomistic level, hence the objective of this report. Various computational tools were employed for this purpose. From our findings, it was revealed that van der Waals (vdW) interactions modulate the binding mechanisms of these inhibitors and play the most important role in the differential inhibitory activities of 11d , 11h, and 11e . The strong hydrogen bond formation between the aliphatic chain of 11d and key residue ARG841 was recognized as the reason for its higher activity and inhibitory potency relative to 11h and 11e . Moreover, the extension of the N‐terminal loop into the active site for vdW interaction with the phenyl group of 11e and carbon–hydrogen bond formed between the aliphatic chain of 11e and LEU718 engendered a higher activity of 11e than 11h .  相似文献   
995.
In recent years, the design, development, and evaluation of several inhibitors of the BACE1 enzyme, as part of Alzheimer's treatment, have gathered the scientific community's interest. Here, a linear regression model was built using binding free energy calculations through the Bennett acceptance ratio method for 20 known inhibitors of the BACE1 enzyme, with a Pearson coefficient of R = 0.88 and R2 = 0.78. The validation of this model was verified employing eight additional random inhibitors, which also gave a linear correlation with R = 0.97 and R2 = 0.93. Furthermore, this linear regression model was also used for proposing the structure of four potential BACE1 inhibitors, and the most active of them gave a theoretical Kd = 10 nM. However, these molecules have not been synthesized yet. Our team used a total time of more than 800 ns for the Molecular Dynamics to carry out this study, and all the software used were freely available.  相似文献   
996.
BACKGROUND There are few effective tools to predict survival in patients with invasive intraductal papillary mucinous neoplasms of the pancreas.AIM To develop comprehensive nomograms to individually estimate the survival outcome of patients with invasive intraductal papillary mucinous neoplasms of the pancreas.METHODS Data of 1219 patients with invasive intraductal papillary mucinous neoplasms after resection were extracted from the Surveillance,Epidemiology,and End Results database,and randomly divided into the training(n=853)and the validation(n=366)cohorts.Based on the Cox regression model,nomograms were constructed to predict overall survival and cancer-specific survival for an individual patient.The performance of the nomograms was measured according to discrimination,calibration,and clinical utility.Moreover,we compared the predictive accuracy of the nomograms with that of the traditional staging system.RESULTS In the training cohort,age,marital status,histological type,T stage,N stage,M stage,and chemotherapy were selected to construct nomograms.Compared with the American Joint Committee on Cancer 7th staging system,the nomograms were generally more discriminative.The nomograms passed the calibration steps by showing high consistency between actual probability and nomogram prediction.Categorial net classification improvements and integrated discrimination improvements suggested that the predictive accuracy of the nomograms exceeded that of the American Joint Committee on Cancer staging system.With respect to decision curve analyses,the nomograms exhibited more preferable net benefit gains than the staging system across a wide range of threshold probabilities.CONCLUSION The nomograms show improved predictive accuracy,discrimination capability,and clinical utility,which can be used as reliable tools for risk classification and treatment recommendations.  相似文献   
997.
The increasing demand for organ donors to supply the increasing number of patients on kidney waiting lists has led to most transplant centers developing protocols that allow safe utilization from donors with special clini cal situations which previously were regarded as contra indications.Deceased donors with previous hepatitis C infection may represent a safe resource to expand the donor pool.When allocated to serology-matched recipi ents,kidney transplantation from donors with hepatitis C may result in an excellent short-term outcome and a significant reduction of time on the waiting list.Specia care must be dedicated to the pre-transplant evaluation of potential candidates,particularly with regard to live functionality and evidence of liver histological damage such as cirrhosis,that could be a contraindication to transplantation.Pre-transplant antiviral therapy could be useful to reduce the viral load and to improve the long-term results,which may be affected by the progression of liver disease in the recipients.An accurate selection of both donor and recipient is mandatory to achieve a satisfactory long-term outcome.  相似文献   
998.
AIM: To evaluate outcomes of radiofrequency ablation(RFA) therapy for early hepatocellular carcinoma(HCC) and identify survival- and recurrence-related factors. METHODS: Consecutive patients diagnosed with early HCC by computed tomography(CT) or magnetic resonance imaging(MRI)(single nodule of ≤ 5 cm, or multi-(up to 3) nodules of ≤ 3 cm each) and who underwent RFA treatment with curative intent between January 2010 and August 2011 at the Instituto do Cancer do Estado de S o Paulo, Brazil were enrolled in the study. RFA of the liver tumors(with 1.0 cm ablative margin) was carried out under CT-fluoro scan and ultrasonic image guidance of the percutaneous ablation probes. Procedure-related complications were recorded. At 1-mo post-RFA and 3-mo intervals thereafter, CT and MRI were performed to assess outcomes of complete response(absence of enhancing tissue at the tumor site) or incomplete response(enhancing tissue remaining at the tumor site). Overall survival and diseasefree survival rates were estimated by the Kaplan-Meier method and compared by the log rank test or simple Cox regression. The effect of risk factors on survival was assessed by the Cox proportional hazard model. RESULTS: A total of 38 RFA sessions were performed during the study period on 34 patients(age in years: mean, 63 and range, 49-84). The mean follow-up time was 22 mo(range, 1-33). The study population showed predominance of male sex(76%), less severe liver disease(Child-Pugh A, n = 26; Child-Pugh B, n = 8), and single tumor(65%). The maximum tumor diameters ranged from 10 to 50 mm(median, 26 mm). The initial(immediately post-procedure) rate of RFAinduced complete tumor necrosis was 90%. The probability of achieving complete response was significantly greater in patients with a single nodule(vs patients with multi-nodules, P = 0.04). Two patients experienced major complications, including acute pulmonary edema(resolved with intervention) and intestinal perforation(led to death). The 1- and 2-year overall survival rates were 82% and 71%, respectively. Sex, tumor size, initial response, and recurrence status influenced survival, but did not reach the threshold of statistical significance. Child-Pugh class and the model for end-stage liver disease score were identified as predictors of survival by simple Cox regression, but only Child-Pugh class showed a statistically significant association to survival in multiple Cox regression analysis(HR = 15; 95%CI: 3-76 mo; P = 0.001). The 1-and 2-year cumulative disease-free survival rates were 65% and 36%, respectively. CONCLUSION: RFA is an effective therapy for local tumor control of early HCC, and patients with preserved liver function are the best candidates.  相似文献   
999.
刘月红  蒋军红 《临床肺科杂志》2020,25(5):760-763,774
目的探讨非小细胞肺癌(NSCLC)患者EGFR、ALK基因突变状态及病理特征,分析二者与患者预后情况相关性。方法收集2015年1月至2018年1月苏州大学附属第一医院病理确诊的NSCLC病例262例,记录患者临床病理特征及转归,采用突变增阻滞系统(ARMS)-Taqman探针法及RT-PCR检测患者肿瘤样本的EGFR和ALK基因外显子突变情况,采用Kaplan-Meier法和Cox风险回归考察不同基因突变情况的预后、临床病理特征与临床结局的相关性。结果262例NSCLC患者中,168例为野生型,ALK突变12例,突变率4.6%;EGFR突变82例,突变率31.30%,其中18号外显子突变2例,19号外显子突变37例,20号外显子突变9例,21号外显子突变31例;各组间年龄、病理类型比较差异有统计学意义,P<0.05;Wild type组中位OS时间11.6月,ALK组中位OS时间15.0月,EGFR组中位OS时间36.8月,EGFR组OS明显优于ALK组OS时间及Wild type组OS时间,P<0.05;EGFR19号外显子突变组、21号外显子突变组OS生存时间显著高于18号外显子突变组和20号外显子突变组,P<0.05;EGFR阴性(RR=15.751,95%CI:9.252~26.816)、鳞癌(RR=18.344,95%CI:6.187~54.388)为OS的危险因素。结论EGFR突变状态、病理类型对非小细胞肺癌预后具有良好的预测价值,鳞癌和EGFR阴性患者生存期短。EGFR基因少见突变(18号外显子、20号外显子)患者的中位OS时间更短。  相似文献   
1000.
目的观察依达拉奉联合尤瑞克林治疗进展性脑梗死的临床疗效。方法将近年来该院收治的90例急性进展性脑梗死患者随机分为治疗组与对照组各45例,两组患者除常规给予拜阿司匹林抗凝、阿托伐他汀降脂、疏血通改善循环等治疗外,对照组另给予依达拉奉治疗,治疗组另给予依达拉奉联合尤瑞克林治疗,观察比较两组患者治疗前后神经功能损伤情况、血液流变学改变及临床疗效。结果治疗组临床疗效优于对照组( P<0.01)。两组神经功能缺损评分和血液流变学各项指标治疗后均有下降( P<0.05或<0.01),且治疗组的下降幅度大于对照组(P<0.01)。结论依达拉奉联合尤瑞克林对进展性脑梗死具有很好的治疗效果。  相似文献   
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