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51.
Cytochrome-c oxidase (ferrocytochrome-c:oxygen oxidoreductase, EC 1.9.3.1) has been isolated from bovine heart mitochondria by the combined use of the non-ionic detergent Triton X-100 as solubilizing agent and hydroxyapatite chromatography as the most important step in the purification of this membrane protein. This method is fast and very reproducible. The enzymic complex, purified in the form of protein/detergent/phospholipid mixed micelles, contains 9.7 mumol heme a per mg protein, and has a high molecular activity (500 mol cytochrome c per s per mol enzyme). These mixed micelles have been studied by laser light scattering, which has shown that the average molecular weight of the micelles is 540 +/- 80 kDa. This implies that cytochrome-c oxidase is purified in the form of a dimer. The average quadratic radius of gyration of the micelles is 40 +/- 10 nm, corresponding in our case to an approximately spherical shape. 相似文献
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Spiros Liras Stanton F. McHardy Martin P. Allen Barb E. Segelstein Steven D. Heck Dianne K. Bryce Anne W. Schmidt Michelle Vanase-Frawley Ernesto Callegari Stafford McLean 《Bioorganic & medicinal chemistry letters》2010,20(2):503-507
The design and synthesis of novel opiates are reported. Based on the message-address principle a novel class of 4,4- and 3,3-biaryl piperidines was designed and synthesized. Biological evaluation confirmed that these compounds exhibit high affinity and selectivity for the delta opioid receptor. Key structure–activity relationships that influence affinity, selectivity, functional activity and clearance are reported. 相似文献
53.
The increase in serum cortisol concentrations following naloxone administration to female pigs was abolished by hypophysial stalk-transection, even though CRH and ACTH stimulated cortisol release in these animals. We suggest that the opioid antagonist enhances cortisol secretion primarily by a central action in pigs. 相似文献
54.
UV irradiation and mitomycin C exposure trigger a protease-activity-dependent inhibition of cell division in Rhodobacter capsulatus, which begins about 2 h after the treatment is applied. UV irradiation also induces a dose-dependent mutagenesis with a maximal rate between 5 and 10 J m-2, with increased synthesis of a protein of Mr approximately 30,000 between 2 and 3 h after UV irradiation. In addition, R. capsulatus has an efficient photoreactivation system that reverses the lethal effects of UV irradiation in the presence of intense visible light. 相似文献
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Restriction-modification systems in Streptomyces antibioticus 总被引:2,自引:0,他引:2
J Sànchez C Barbès A Hernandez C R de los Reyes Gavilàn C Hardisson 《Canadian journal of microbiology》1985,31(10):942-946
Several restriction systems were detected in different strains of Streptomyces antibioticus by using actinophages as biological indicators. Adsorption of phages to the bacteria, together with the study of the efficiency of plating gave an initial indication of restriction in three strains. The alternation of efficiency of plating values obtained from restricting and nonrestricting hosts, gave evidence for the presence of a restriction-modification system in another strain. No common modification systems were detected among the different strains tested. Two specific endonucleases with a possible role in restriction were detected in strains ATCC 11891 and ETH 7451, respectively. 相似文献
57.
Kenneth Cusi Scott Isaacs Diana Barb Rita Basu Sonia Caprio W. Timothy Garvey Sangeeta Kashyap Jeffrey I. Mechanick Marialena Mouzaki Karl Nadolsky Mary E. Rinella Miriam B. Vos Zobair Younossi 《Endocrine practice》2022,28(5):528-562
ObjectiveTo provide evidence-based recommendations regarding the diagnosis and management of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) to endocrinologists, primary care clinicians, health care professionals, and other stakeholders.MethodsThe American Association of Clinical Endocrinology conducted literature searches for relevant articles published from January 1, 2010, to November 15, 2021. A task force of medical experts developed evidence-based guideline recommendations based on a review of clinical evidence, expertise, and informal consensus, according to established American Association of Clinical Endocrinology protocol for guideline development.Recommendation SummaryThis guideline includes 34 evidence-based clinical practice recommendations for the diagnosis and management of persons with NAFLD and/or NASH and contains 385 citations that inform the evidence base.ConclusionNAFLD is a major public health problem that will only worsen in the future, as it is closely linked to the epidemics of obesity and type 2 diabetes mellitus. Given this link, endocrinologists and primary care physicians are in an ideal position to identify persons at risk on to prevent the development of cirrhosis and comorbidities. While no U.S. Food and Drug Administration-approved medications to treat NAFLD are currently available, management can include lifestyle changes that promote an energy deficit leading to weight loss; consideration of weight loss medications, particularly glucagon-like peptide-1 receptor agonists; and bariatric surgery, for persons who have obesity, as well as some diabetes medications, such as pioglitazone and glucagon-like peptide-1 receptor agonists, for those with type 2 diabetes mellitus and NASH. Management should also promote cardiometabolic health and reduce the increased cardiovascular risk associated with this complex disease. 相似文献
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Bernardo CG González JJ Sanz L Barbón E Noval JG Fresno MF Aza J 《The International journal of biological markers》2004,19(3):190-195
INTRODUCTION AND AIMS: The role of genetic factors in the etiology and prognosis of patients with sporadic colorectal cancer is controversial. We have therefore investigated the biological and clinicopathological influence of immunohistochemical MSH2 expression in colorectal cancer. PATIENTS AND METHODS: A total of 49 consecutive patients with unselected colorectal cancer operated on in our unit were included in the study. All tumors were resected and tumor specimens were evaluated for MSH2 expression. Clinicopathological data and patient survival were correlated with MSH2 staining. Uni- and multivariate analyses were performed. The minimum follow-up period was five years. RESULTS: Curative resection was performed in 34 patients (64.9%), 14 of whom subsequently relapsed. At the end of the overall follow-up 25 (51%) patients had died, 21 of cancer-related causes. Twenty-eight patients (57.1%) were negative for MSH2 staining. Only vascular invasion was significantly correlated with MSH2 expression (lower median values; p=0.04). The overall median survival was 47.9 months (95% CI=27-86.6%). Multivariate analysis of variables in relation to survival showed that T stage (p=0.001), N stage (p<0.001) and MSH2 expression (p=0.01) were independent factors for survival. CONCLUSIONS: Reduced MSH2 expression is frequent in unselected colorectal cancer patients. Only vascular invasion was correlated with MSH2 expression in this study. Survival was related to TN stage and MSH2 staining. 相似文献