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871.
W. J. Malaisse J. C. Hutton A. Sener J. Levy A. Herchuelz G. Devis G. Somers 《The Journal of membrane biology》1978,38(3):193-208
Summary The role of extracellular Ca2+ in the regulation of islet function is investigated. Decreasing extracellular Ca2+ concentrations cause a dose-related inhibition of glucose-induced insulin release. Whereas the efflux of45Ca from perifused islets is transiently increased on exposure to Ca2+-deprived media, it is unaffected by a partial lowering of the extracellular Ca2+ concentration. Under the latter condition, therefore, the observed reduction in the size of the islets' exchangeable calcium pool(s) appears to be due to reduced Ca2+ entry. The proper effect of glucose on Ca handling by the islets is apparently not affected by a lowering in the extracellular Ca2+ concentration. Nevertheless, in islets exposed to glucose and incubated in Ca2+-deprived media, glucose uptake and oxidation and lactate output are decreased, whereas the islet ATP level is increased, as if extracellular Ca2+ shortage were to affect not only the cellular pool of Ca regulating insulin release, but also energy-consuming processes possibly located at the cell membrane. 相似文献
872.
D. J. M. Schmedding W. Somers C. van Dijk H. Günther J. P. van der Lugt H. Simon 《Biotechnology Techniques》1992,6(5):439-444
Summary The rate of the bio-electrochemical conversion of crotonic acid into butyric acid by enoate reductase is dependent on the
type of viologen used. This illustrates that the reaction between enzyme and mediator, rather than the reaction between enzyme
and crotonic acid, is rate limiting. Thus for bio-electrochemical conversion of enoates into saturated chiral acids immobilization
of enoate reductase is beneficial from a kinetic point of view. The highest rate constant (k'=7.0×106 M−1.s−1) was measured using mono-N-(aminopropyl) viologen. 相似文献
873.
874.
The inter-relationship between the age of carrot roots at harvest and infection by Mycocentrospora acerina in storage 总被引:1,自引:0,他引:1
Infection of carrot roots by Mycocenlrospora acerina in chill storage (3.5 °C) following inoculation with chlamydospores was studied in 1973–74 and 1974–75. AREAS of intact periderm were only rarely infected, and the high level of periderm resistance predominated over other variables. However, wound infection tended to increase with depth of wound and with increasing age of the plants at harvest. Irrespective of age of root or depth of wound, roots were comparatively resistant to infection at harvest and early in storage, resistance being expressed as a restriction of mycelial growth on the wound surface or localisation of the lesion. Increasing susceptibility with time in storage, depth of wounds, or age at harvest, resulted in larger numbers of inoculated sites becoming infected and a more rapid development from localised to progressive lesions. 相似文献
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In an African female infant with exstrophy who was a candidate for complete reconstruction of the urinary tract, pelvis, and abdominal wall, the treatment program was simplified by performing iliac osteotomies at the same time as the other repairs, using a single transverse lumbosacral incision for access. A series of 3 wire loops held the symphysis in apposition. A plaster spica, followed by a plaster girdle, minimized the tension on the pubic wires. We believe that we obtained, by this method, superior strength and a better appearance of the abdominal wall and perineum. 相似文献
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Emma Rose McGlone Iain Carey Vladica Veli
kovi Prem Chana Kamal Mahawar Rachel L. Batterham James Hopkins Peter Walton Robin Kinsman James Byrne Shaw Somers David Kerrigan Vinod Menon Cynthia Borg Ahmed Ahmed Bruno Sgromo Chandra Cheruvu Gul Bano Catherine Leonard Howard Thom Carel W le Roux Marcus Reddy Richard Welbourn Peter Small Omar A. Khan 《PLoS medicine》2020,17(12)
BackgroundAlthough bariatric surgery is well established as an effective treatment for patients with obesity and type 2 diabetes mellitus (T2DM), there exists reluctance to increase its availability for patients with severe T2DM. The aims of this study were to examine the impact of bariatric surgery on T2DM resolution in patients with obesity and T2DM requiring insulin (T2DM-Ins) using data from a national database and to develop a health economic model to evaluate the cost-effectiveness of surgery in this cohort when compared to best medical treatment (BMT).Methods and findingsClinical data from the National Bariatric Surgical Registry (NBSR), a comprehensive database of bariatric surgery in the United Kingdom, were extracted to analyse outcomes of patients with obesity and T2DM-Ins who underwent primary bariatric surgery between 2009 and 2017. Outcomes for this group were combined with data sourced from a comprehensive literature review in order to develop a state-transition microsimulation model to evaluate cost-effectiveness of bariatric surgery versus BMT for patients over a 5-year time horizon. The main outcome measure for the clinical study was insulin cessation at 1-year post-surgery: relative risks (RR) summarising predictive factors were determined, unadjusted, and after adjusting for variables including age, initial body mass index (BMI), duration of T2DM, and weight loss. Main outcome measures for the economic evaluation were total costs, total quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) at willingness-to-pay threshold of GBP£20,000.A total of 2,484 patients were eligible for inclusion, of which 1,847 had 1-year follow-up data (mean age of 51 years, mean initial BMI 47.2 kg/m2, and 64% female). 67% of patients no longer required insulin at 1-year postoperatively: these rates persisted for 4 years. Roux-en-Y gastric bypass (RYGB) was associated with a higher rate of insulin cessation (71.7%) than sleeve gastrectomy (SG; 64.5%; RR 0.92, confidence interval (CI) 0.86–0.99) and adjustable gastric band (AGB; 33.6%; RR 0.45, CI 0.34–0.60; p < 0.001). When adjusted for percentage total weight loss and demographic variables, insulin cessation following surgery was comparable for RYGB and SG (RR 0.97, CI 0.90–1.04), with AGB having the lowest cessation rates (RR 0.55, CI 0.40–0.74; p < 0.001). Over 5 years, bariatric surgery was cost saving compared to BMT (total cost GBP£22,057 versus GBP£26,286 respectively, incremental difference GBP£4,229). This was due to lower treatment costs as well as reduced diabetes-related complications costs and increased health benefits. Limitations of this study include loss to follow-up of patients within the NBSR dataset and that the time horizon for the economic analysis is limited to 5 years. In addition, the study reflects current medical and surgical treatment regimens for this cohort of patients, which may change.ConclusionsIn this study, we observed that in patients with obesity and T2DM-Ins, bariatric surgery was associated with high rates of postoperative cessation of insulin therapy, which is, in turn, a major driver of overall reductions in direct healthcare cost. Our findings suggest that a strategy utilising bariatric surgery for patients with obesity and T2DM-Ins is cost saving to the national healthcare provider (National Health Service (NHS)) over a 5-year time horizon.Emma Rose McGlone and colleagues report the clinical and cost- effectiveness of bariatric surgery for patients with Type 2 diabetes. 相似文献
880.