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71.

Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
72.
Several regulatory bodies have agreed that low-dose radiation used in medical imaging is a weak carcinogen that follows a linear, non-threshold model of cancer risk. While avoiding radiation is the best course of action to mitigate risk, computed tomography (CT) scans are often critical for diagnosis. In addition to the as low as reasonably achievable principle, a more concrete method of dose reduction for common CT imaging exams is the use of a diagnostic reference level (DRL). This paper examines Canada's national DRL values from the recent CT survey and compares it to published provincial DRLs as well as the DRLs in the United Kingdom and the United States of America for the 3 most common CT exams: head, chest, and abdomen/pelvis. Canada compares well on the international scale, but it should consider using more electronic dose monitoring solutions to create a culture of dose optimization.  相似文献   
73.
74.
目的:建立液相色谱-串联质谱法(UPLC-MS/MS)同时测定人血浆中头孢哌酮与舒巴坦的浓度,分析头孢哌酮/舒巴坦血药浓度监测结果,为临床合理用药提供参考。方法:以氯唑沙宗为内标,采用Waters BEHC18柱(2.1 mm×100 mm,1.7 μm)进行分离,通过串联质谱仪,负离子检测模式下,以多反应监测(MRM)方式进行定量测定。对某院2018年以不同给药方案进行治疗的73例住院患者测定的头孢哌酮/舒巴坦血药浓度结果进行分析。结果:头孢哌酮与舒巴坦在测定条件下1~200 mg·L-1范围内线性关系良好,两者日内精密度RSD均<10%,基质效应分别为(72.77±0.99)%与(75.72±0.11)%,提取回收率均>90%。73例患者共监测血药浓度96次,其中不同给药方案2 g,q8 h(43例次);2 g,q12 h(26例次);2 g,q6 h(27例次),各组头孢哌酮血药浓度的中位数分别为34.12 mg·L-1(4.12~177.79 mg·L-1)、31.23 mg·L-1(1.89~251.8 mg·L-1)、59.96 mg·L-1(1.77~140.58 mg·L-1),舒巴坦血药浓度的中位数分别为6.3 mg·L-1(0.61~136.01 mg·L-1)、28.83 mg·L-1(0.5~133.69 mg·L-1)、11.17 mg·L-1(0.73~143.53 mg·L-1)。Mann-Whitney U检验显示,头孢哌酮血药浓度结果无统计学差异(P>0.05),舒巴坦有统计学差异(P<0.05)。结论:本检测方法操作简便、快速、重复性好,可满足临床头孢哌酮与舒巴坦浓度的检测;头孢哌酮/舒巴坦在不同给药方案下血药浓度结果与个体差异相关,有必要开展血药浓度监测并依据结果适时调整用药方案,提高治疗效果减少耐药率的发生。  相似文献   
75.
正确编制“本年盈余与预算结余差异调节表”是公立医院执行《政府会计制度》的一大难点,现有的几种差异调节方法存在诸多不足,核算正确与否依赖会计人员的基本素质,而且工作量巨大。以财务会计与预算会计差异产生的基本原理为基础,利用计算机软件实时校验并自动登记差异,是简便、高效、准确编制“本年盈余与预算结余差异调节表”的方法,本文对此进行了举例说明。  相似文献   
76.
Abstract

This research explores how the level of consumers’ need for cognition (NFC) is associated with celebrity endorser credibility and examines its effects on advertising-related attitudes. A 3 (endorser types: actor/actress, athlete, TV personality/talent) × 2 (endorser’s gender) factorial experiment with 435 Japanese consumers was conducted. Concerning Japanese OTC drug advertising, lower NFC individuals perceived celebrity endorsers as more credible in comparison to higher NFC individuals. The main effects of NFC and endorser type on endorser credibility existed; however, no interaction between the two variables was found. The endorser type had an influence on attitudes toward ads and the advertised brand.  相似文献   
77.
《Cancer radiothérapie》2020,24(4):306-315
French regulations about research ethics are based on the so-called Jardé law, which defines researches involving human beings. Researches involving human beings require the submission of research protocols to a committee for protection of persons with a precise list of documents to submit for a favourable opinion. This law describes different categories of researches and determines the ethical procedures to apply before setting up a research protocol. This issue of categorisation is central and must be taken into account by researchers from the beginning of the research process. Researches considered as not involving human beings also require a set of ethical precautions focused on patients’ information and the collection of their non-opposition (due to the application of the General Data Protection Regulation adopted by the European Parliament). Thus, many regulations exist and they require a real work for researchers to meet these requirements in research ethics. This article aims to summarise French regulations. Selected examples are specifically taken into the field of radiation oncology research.  相似文献   
78.
ObjectiveProgrammed death ligand 1 (PD-L1) has been reported to be connected to prognosis in individuals with malignant pleural mesothelioma (MPM), although there is no consensus based on data from previous studies. Accordingly, this quantitative meta-analysis investigated prognostic and clinicopathological utility of PD-L1 in patients with MPM.MethodsA comprehensive search of the PubMed, Web of Science, Embase, and Cochrane Library databases for articles published up to October 4, 2019 was performed. Studies using immunohistochemical techniques to detect/quantify the expression of PD-L1 in MPM tissue were enrolled in the analysis. The combined hazard ratio (HR) and corresponding 95% confidence interval (CI) was applied to assess the association between PD-L1 expression and overall survival (OS).ResultsA total of 11 studies comprising 1606 patients was included in the present meta-analysis. For OS, pooled data revealed an HR of 1.50 (95% CI 1.32–1.70; p < 0.001), suggesting that patients with PD-L1 overexpression experience inferior OS. Subgroup analysis revealed that elevated PD-L1 remained a significant prognostic indicator for worse OS, irrespective of sample size, cut-off value, ethnicity, and Newcastle-Ottawa Scale score. Moreover, PD-L1 overexpression was associated with non-epithelioid histology (odds ratio 4.30 [95% CI 1.89–9.74]; p < 0.001).ConclusionsResults of this meta-analysis show that elevated expression of PD-L1 could be a factor predicting poorer survival in patients with MPM.  相似文献   
79.
80.
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