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101.
IntroductionThe Bombay phenotype is a rare blood group determined by the absence of H antigens. Bombay individuals produce anti-H, a clinically significant antibody that react against all ABO blood group. Anti-H can mask underlying alloantibody during antibody investigation, a challenge in current transfusion practice. The aim of this article is to explore saliva inhibition, a novel method to detect underlying alloantibody in Bombay individuals.Case PresentationThe case is a 93-year-old female transfused with pre-donated autologous blood for a surgery. We determined anti-H subclass and thermal amplitude, secretor status, and optimal ratio of saliva and Bombay plasma. Plasma samples containing anti-H were spiked with anti-Fy(a) to determine the effectiveness of saliva inhibition in uncovering underlying alloantibodies.ResultsAnti-H was confirmed to be predominately IgM with broad thermal amplitude. Tube immediate spin (IS) showed stronger anti-H reactivity compared to column agglutination technology (CAT). Spiked anti-Fy(a) was successfully detected using saliva inhibition method.ConclusionTube IS appears more sensitive to anti-H. Saliva inhibition appears to be a promising method to detect underlying alloantibody in the plasma of Bombay phenotype individuals.  相似文献   
102.
To explore the mechanism of silver and rhodium catalysis and reveal the origin of the chemo- and enantioselectivity of the reaction, density functional theory calculations were performed on the first silver-catalyzed highly enantioselective carbene transfer reaction. The calculation results reveal that when silver is used as a catalyst, due to the participation of the phosphate anion in the transition state, the enhanced nucleophilicity of the α-diazoacetamide unit promotes smooth dearomatization before generation of the silver carbene. Because the generated rhodium carbene has stronger electrophilicity, typical carbene reactions (C–H insertion and the Büchner reaction) are favored. In addition, in the process of silver catalyzed dearomatization, the formation of an R-type transition state is determined by the small torsion energy and strong interaction energy.

DFT calculations reveal the mechanism, as well as the origins of chemoselectivity and enantioselectivity in the Ag vs. Rh catalyzed intramolecular carbene transfer reaction.  相似文献   
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OBJECTIVE: To explore the extent and impact of professional boundary crossings in metropolitan, regional and rural mental health practice in Victoria and identify strategies mental health clinicians use to manage dual relationships. METHOD: Nine geographically located focus groups consisting of mental health clinicians: four focus groups in rural settings; three in a regional city and two in a metropolitan mental health service. A total of 52 participants were interviewed. RESULTS: Data revealed that professional boundaries were frequently breached in regional and rural settings and on occasions these breaches had a significantly negative impact. Factors influencing the impact were: longevity of the clinician's relationship with the community, expectations of the community, exposure to community 'gossip' and size of the community. Participants reported greater stress when the boundary crossing affected their partner and/or children. Clinicians used a range of proactive and reactive strategies, such as private telephone number, avoidance of social community activities, when faced with a potential boundary crossing. The feasibility of reactive strategies depended on the service configuration: availability of an alternative case manager, requirement for either patient or clinician to travel. The greater challenges faced by rural and regional clinicians were validated by metropolitan participants with rural experience and rural participants with metropolitan experience. CONCLUSIONS: No single strategy is used or appropriate for managing dual relationships in rural settings. Employers and professional bodies should provide clearer guidance for clinicians both in the management of dual relationships and the distinction between boundary crossings and boundary violation. Clinicians are clearly seeking to represent and protect the patients' interests; consideration should be given by consumer groups to steps that can be taken by patients to reciprocate.  相似文献   
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Tickborne diseases (TBDs) such as Lyme disease result in ≈500,000 diagnoses annually in the United States. Various methods can reduce the abundance of ticks at small spatial scales, but whether these methods lower incidence of TBDs is poorly understood. We conducted a randomized, replicated, fully crossed, placebo-controlled, masked experiment to test whether 2 environmentally safe interventions, the Tick Control System (TCS) and Met52 fungal spray, used separately or together, affected risk for and incidence of TBDs in humans and pets in 24 residential neighborhoods. All participating properties in a neighborhood received the same treatment. TCS was associated with fewer questing ticks and fewer ticks feeding on rodents. The interventions did not result in a significant difference in incidence of human TBDs but did significantly reduce incidence in pets. Our study is consistent with previous evidence suggesting that reducing tick abundance in residential areas might not reduce incidence of TBDs in humans.  相似文献   
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Approximately 25 % of mismatch repair (MMR) variants are exonic nucleotide substitutions. Some result in the substitution of one amino acid for another in the protein sequence, so-called missense variants, while others are silent. The interpretation of the effect of missense and silent variants as deleterious or neutral is challenging. Pre-symptomatic testing for clinical use is not recommended for relatives of individuals with variants classified as ‘of uncertain significance’. These relatives, including non-carriers, are considered at high-risk as long as the contribution of the variant to disease causation cannot be determined. This results in continuing anxiety, and the application of potentially unnecessary screening and prophylactic interventions. We encountered a large Irish Lynch syndrome kindred that carries the c.544A>G (p.Arg182Gly) alteration in the MLH1 gene and we undertook to study the variant. The clinical significance of the variant remains unresolved in the literature. Data are presented on cancer incidence within five kindreds with the same germline missense variant in the MLH1 MMR gene. Extensive testing of relevant family members in one kindred, a review of the literature, review of online MMR mutation databases and use of in silico phenotype prediction tools were undertaken to study the significance of this variant. Clinical, histological, immunohistochemical and molecular evidence from these families and other independent clinical and scientific evidence indicates that the MLH1 p.Arg182Gly (c.544A>G) change causes Lynch syndrome and supports reclassification of the variant as pathogenic.  相似文献   
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Ovarian cancer is an important health concern worldwide. The majority of patients present with advanced disease, and despite initial chemosensitivity, most relapse and die from their disease. Better therapeutic options are urgently required. Maximal surgical debulking in combination with platinum/taxane chemotherapy has been the standard of care in advanced ovarian cancer since the mid-1990s. Trials investigating the addition of a third chemotherapeutic agent have disappointingly failed to demonstrate benefit. Intra-peritoneal therapy demonstrated improvements in outcomes in some trials, but at the cost of increased toxicity and inconvenience. Encouragingly, prospective data has now demonstrated benefits with bevacizumab in both the first-line and relapsed settings; however, interpretation is complex, particularly considering recent data demonstrating non-inferiority of neo-adjuvant chemotherapy with delayed primary surgery, and other data demonstrating a substantial improvement in outcome as a result of first-line paclitaxel dose fractionation. This article reviews the recent advances in ovarian cancer treatment and discusses current management and key areas for future research.  相似文献   
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