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Whole-genome sequencing of non-H2S-producing Salmonella enterica serovar Typhimurium and S. enterica serovar Infantis isolates from poultry meat revealed a nonsense mutation in the phsA thiosulfate reductase gene and carriage of a CMY-2 β-lactamase. The lack of production of H2S might lead to the incorrect identification of S. enterica isolates carrying antimicrobial resistance genes.  相似文献   
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Congenital junctional ectopic tachycardia is a rare tachyarrhythmia with high mortality. A pharmacological approach in early infancy is regarded as the first‐line therapeutic option. Pharmacologically, amiodarone alone or in combination with other drugs is the most commonly reported effective agent for congenital junctional ectopic tachycardia, but it has many adverse effects. Here we report the case of a 40‐day‐old infant. The clinical course suggests that combined oral flecainide and propranolol is an effective alternative therapy for early infants. Esophageal lead electrocardiography may give a clear diagnosis of junctional ectopic tachycardia.  相似文献   
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Background: It has been hypothesized that β‐3 adrenergic receptor and peroxisome proliferator‐activated receptor gamma (PPARγ) might have gene–environmental and gene–gene interactions in periodontal disease. The purpose of this study is to elucidate the interaction between β‐3 adrenergic receptor and PPARγ gene polymorphism with periodontal disease. Methods: Three hundred thirty‐two postmenopausal females were enrolled, and their serum high‐sensitivity C‐reactive protein (hsCRP) and hemoglobin A1c (HbA1c) were examined. β‐3 adrenergic receptor and PPARγ genotypes were then determined. An oral examination was performed. The number of remaining teeth was counted, and the probing depth (PD) and clinical attachment level (CAL) were measured. Prevalence‐rate ratios (PRRs) were calculated by multiple Poisson regression analyses to evaluate the relationship among periodontal disease markers, such as the number of sites with CAL 4 to 5 or ≥6 mm or PD 4 to 5 or ≥6 mm, and β‐3 adrenergic receptor polymorphisms, PPARγ polymorphisms, and the interaction term adjusted by age, hsCRP, and HbA1c, after converting the number of remaining teeth (n) to an offset variable. Results: In the participants with body mass index (BMI) ≥25, PRRs of β‐3 adrenergic receptor genotype (Trp/Arg and Arg/Arg) for periodontal disease markers were 0.13 to 0.70 (P <0.0001 to 0.74), those of PPARγ genotype (Pro/Pro) were 0.66 to 3.14 (P = 0.01 to 0.68), and those of the interaction term for the two genotypes were 1.69 to 12.61 (P <0.0001 to 0.33). However, in the participants with BMI <25, a constant tendency was not observed. Conclusion: The results confirmed a positive relationship between the interaction term for β‐3 adrenergic receptor genotype and PPARγ genotype and various periodontal markers in obese elderly females.  相似文献   
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Fridovich identified CuZnSOD in 1969 and manganese superoxide dismutase (MnSOD) in 1973, and proposed ”the Superoxide Theory,” which postulates that superoxide (O2•−) is the origin of most reactive oxygen species (ROS) and that it undergoes a chain reaction in a cell, playing a central role in the ROS producing system. Increased oxidative stress on an organism causes damage to cells, the smallest constituent unit of an organism, which can lead to the onset of a variety of chronic diseases, such as Alzheimer’s, Parkinson’s, amyotrophic lateral sclerosis and other neurological diseases caused by abnormalities in biological defenses or increased intracellular reactive oxygen levels. Oxidative stress also plays a role in aging. Antioxidant systems, including non-enzyme low-molecular-weight antioxidants (such as, vitamins A, C and E, polyphenols, glutathione, and coenzyme Q10) and antioxidant enzymes, fight against oxidants in cells. Superoxide is considered to be a major factor in oxidant toxicity, and mitochondrial MnSOD enzymes constitute an essential defense against superoxide. Mitochondria are the major source of superoxide. The reaction of superoxide generated from mitochondria with nitric oxide is faster than SOD catalyzed reaction, and produces peroxynitrite. Thus, based on research conducted after Fridovich’s seminal studies, we now propose a modified superoxide theory; i.e., superoxide is the origin of reactive oxygen and nitrogen species (RONS) and, as such, causes various redox related diseases and aging.  相似文献   
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