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Base catalysed exchange with sodium hydroxide, calcium oxide or N,N,N,N-tetramethylguanidine in deuterium oxide is a viable procedure for the preparation of terminally deuterated alkynes for those alkynes stable to strong base. The use of silver perchlorate as a catalyst is an alternative practical option when labelling alkynes which are sensitive to base or contain functionalities which would lead to labelling elsewhere in the molecule. Labelling with this catalyst takes place smoothly at ambient temperature in a mixture of N,N-dimethylformamide and deuterium oxide.  相似文献   
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ContextThere is no clear definition of what constitutes a good death or its features. Patients, caregivers, physicians, and relatives have different notions of a good death. Discussions have been driven by academic perspectives, with little research available on the patients' perspectives.ObjectivesTo explore the notions of a good death from the patients' perspective.MethodsA systematic literature search was conducted up to November 2017 using CINAHL®, MEDLINE®, EMBASE®, and PsycINFO® databases. Search terms used were “quality of death,” “good death,” “quality of dying,” or “good dying.” Scientific empirical studies that included the exploration of the notion of a good death in adult patients with advanced and life-threatening diseases were selected separately by two researchers. Hawker's et al. criteria were used to assess the quality of articles. The analysis was conducted using a thematic analysis.ResultsTwo thousand six hundred and fifty two titles were identified; after elimination of duplicates, screening, and final selection, 29 relevant publications remained for analysis. Sample populations included patients with terminal diseases (AIDS, cardiovascular disease, and cancer). Core elements for a “good death” included control of pain and symptoms, clear decision-making, feeling of closure, being seen and perceived as a person, preparation for death, and being still able to give something to others; whereas other factors such as culture, financial issues, religion, disease, age, and life circumstances were found to shape the concept across groups. Studies agree on the individuality of death and dying while revealing a diverse set of preferences, regarding not only particular attributes but also specific ways in which they contribute to a good death.ConclusionsAlthough sharing common core elements, patients' notions of good death are individual, unique, and different. They are dynamic in nature, fluctuating within particular groups and during the actual process of dying. Formal and informal caregivers should carefully follow-up and respect the patient's individual concepts and preferences regarding death and dying, while attending to shared core elements, to better adjust clinical decisions.  相似文献   
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《Vaccine》2020,38(31):4783-4791
A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development.  相似文献   
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目的 探讨钙结合蛋白A6(S100A6)经终末糖基化产物受体(RAGE)介导影响肥胖儿童血管内皮损伤的机制,为进一步提出有针对性的治疗方案提供依据。方法 选取十堰市妇幼保健院2015年7月-2018年7月收治的肥胖患儿91例,根据患儿是否存在血管内皮损伤分成损伤组(n=43)、无损伤组(n=48)。选取同期于本院体检的健康体检儿童45例作为对照组。三组受检者均于入院当日采血检测血清S100A6与游离RAGE(sRAGE)水平,并测定三组血管内皮损伤标志物,包括血管内皮黏附分子-1(sVCAM-1)、可溶性细胞黏附分子-1(sICAN-1)、血管性血友病因子(vWF)水平,检测方法为酶联免疫吸附法。经Pearson线性相关分析S100A6、sRAGE与血管内皮损伤标志物间的相关性。结果 损伤组血清S100A6、sRAGE水平高于无损伤组、对照组,差异有统计学意义(P<0.05)。损伤组血清sVCAM-1、vWF、sICAN-1水平高于无损伤组、对照组,差异有统计学意义(P<0.05)。经Pearson线性相关分析提示S100A6、sRAGE与sVCAM-1、vWF、sICAN-1均呈正相关(P<0.05)。结论 与正常儿童及无血管内皮损伤的肥胖儿童相比,有血管内皮损伤的肥胖儿童血清S100A6、sRAGE明显上调,这可能与sRAGE增高导致S100A6上调,而进一步致sVCAM-1、vWF、sICAN-1水平增高有关。  相似文献   
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Dietary supplements and foods can interact with various drugs, leading to possible clinical concerns. This study aimed to investigate the effect of orally administered sinapic acid (SA) on the pharmacokinetics of aripiprazole (APZ) in rats and its possible modulatory effects on hepatic cytochrome P450 (CYP3A2 and CYP2D6) expression in the liver tissues. Single dose and multiple dose parallel groups of wistar rats were categorized into six groups (n = 6 each) which abstained from food for 12 h prior to the experiment, while water was allowed ad libitum. The investigation was carried out for single dose: Group I was treated with normal saline orally for 15 days (normal control). Group II was administered normal saline orally for 15 days and received APZ (3 mg/kg p.o.) on day 15. Group III received SA (20 mg/kg p.o.) for 15 days and received APZ (3 mg/kg p.o.) on day 15. Group IV was treated with SA (20 mg/kg p.o.) for 15 days. For the multiple dose study, Group I was treated with normal saline orally for 15 days (normal control); Group II received APZ (3 mg/kg p.o.) daily for 15 days; Group III was administered with SA (20 mg/kg p.o.) and APZ (3 mg/kg p.o.) for 15 days and Group IV received SA (20 mg/kg p.o.) for 15 days. The group I and IV were kept common in single and multiple dose groups. After last APZ dose, plasma samples were collected and APZ concentrations were determined using an UPLC-MS/MS technique. The pharmacokinetic parameters were calculated using a non-compartmental analysis. The concomitant administration of APZ with SA (as single or multiple dose) resulted in an increase in APZ absorption and a decrease on its systemic clearance. This was associated with a reduction in CYP3A2 and CYP2D6 protein expressions by 33–43% and -71–68% after the single and multiple co-administration, which are two enzymes responsible of the metabolism of APZ. Therefore, a reduction in the metabolic clearance appears to be the mechanism underlying the drug interaction of dietary supplement containing SA with APZ. Therefore, the concomitant administration of SA and APZ should be carefully viewed. Further investigations are required to assess the clinical significance of such observations in humans.  相似文献   
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【摘要】目的:建立注射用糜蛋白酶中组胺类物质检查方法。 方法:采用组胺检查法对注射用糜蛋白酶中组胺类物质进行限度检查方法学研究,并与现行猫法进行比较研究。结果:加标回收率86%~117%;豚鼠法方法特异性(真阴性率)100%,灵敏度(真阳性率)70%,猫法方法特异性100%,灵敏度70%;四个实验室室内重复性分别为82%、75%、83%、81%;实验室间重复性为92.9%~96.4%.结论:该方法准确与猫法相当、重复性好,可作为降压物质检查法的替代方法。  相似文献   
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