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81.
The purpose of this study was to explore how the muscles which control postural body segments are activated during bilateral isometric ramp pushes exerted with the upper limbs by seated subjects. The paradigm under study presents the advantage that the subject is in a quasi-static posture, and since upper limbs are stretched out, the dynamic phenomena, which might occur, can only originate from the rest of the body, which means from the postural chain. A dynamometer was used to measure the horizontal force, Fx, exerted on the bar, and a custom-designed force-plate was used to measure global reaction forces (Rx) and displacement of the centre of pressure (Xp) along the antero-posterior axis. Electromyograms (EMGs) were picked up by bipolar surface electrodes from 14 muscles crossing the lower limb, pelvis, trunk and upper limb joints. It was shown that transient push efforts require monotonous EMG increase in postural as well as in focal muscles. The EMG sequence starts with the postural muscles and ends with the focal ones. The postural EMG sequence is anticipatory. It is concluded that the EMG sequence is programmed according to the task parameters, and that its role is to counteract in advance the perturbing effect of the effort, in order to allow the effort to be performed efficiently. It is suggested that excitation between the postural muscles is distributed according to their biomechanical role in relation to the supports.  相似文献   
82.
BackgroundObesity has been described as a protective factor in cardiovascular and other diseases being expressed as ‘obesity paradox’. However, the impact of obesity on clinical outcomes including mortality in COVID-19 has been poorly systematically investigated until now. We aimed to compare clinical outcomes among COVID-19 patients divided into three groups according to the body mass index (BMI).MethodsWe retrospectively collected data up to May 31st, 2020. 3635 patients were divided into three groups of BMI (<25 kg/m2; n = 1110, 25?30 kg/m2; n = 1464, and >30 kg/m2; n = 1061). Demographic, in-hospital complications, and predictors for mortality, respiratory insufficiency, and sepsis were analyzed.ResultsThe rate of respiratory insufficiency was more recorded in BMI 25?30 kg/m2 as compared to BMI < 25 kg/m2 (22.8% vs. 41.8%; p < 0.001), and in BMI > 30 kg/m2 than BMI < 25 kg/m2, respectively (22.8% vs. 35.4%; p < 0.001). Sepsis was more observed in BMI 25?30 kg/m2 and BMI > 30 kg/m2 as compared to BMI < 25 kg/m2, respectively (25.1% vs. 42.5%; p = 0.02) and (25.1% vs. 32.5%; p = 0.006). The mortality rate was higher in BMI 25?30 kg/m2 and BMI > 30 kg/m2 as compared to BMI < 25 kg/m2, respectively (27.2% vs. 39.2%; p = 0.31) (27.2% vs. 33.5%; p = 0.004). In the Cox multivariate analysis for mortality, BMI < 25 kg/m2 and BMI > 30 kg/m2 did not impact the mortality rate (HR 1.15, 95% CI: 0.889?1.508; p = 0.27) (HR 1.15, 95% CI: 0.893?1.479; p = 0.27). In multivariate logistic regression analyses for respiratory insufficiency and sepsis, BMI < 25 kg/m2 is determined as an independent predictor for reduction of respiratory insufficiency (OR 0.73, 95% CI: 0.538?1.004; p = 0.05).ConclusionsHOPE COVID-19-Registry revealed no evidence of obesity paradox in patients with COVID-19. However, Obesity was associated with a higher rate of respiratory insufficiency and sepsis but was not determined as an independent predictor for a high mortality.  相似文献   
83.
IntroductionThere is controversy regarding the ideal pancreaticojejunostomy technique after pancreaticoduodenectomy. Many authors consider the external Wirsung stenting technique to be associated with a low incidence of fistula, morbidity and mortality. We analyse our experience with this technique.Patients and methodsA retrospective analysis of the morbidity and mortality of a series of 80 consecutive patients who had been treated surgically over a 6.5-year period for pancreatic head or periampullary tumors, performing pancreaticoduodenectomy and pancreaticojejunostomy with external Wirsung duct stenting.ResultsMean patient age was 68.3 ± 9 years, and the resectability rate was 78%. The texture of the pancreas was soft in 51.2% of patients and hard in 48.8%. Pylorus-preserving resection was performed in 43.8%. Adenocarcinoma was the most frequent tumor (68.8%), and R0 was confirmed in 70% of patients. Biochemical fistula was observed in 11.2%, pancreatic fistula grade B in 12.5% and C in 2.5%, whereas the abdominal reoperation rate was 10%. Median postoperative hospital stay was 16 days, and postoperative and 90-day mortality was 2.5%. Delayed gastric emptying was observed in 36.3% of patients, de novo diabetes in 12.5%, and exocrine insufficiency in 3. Patient survival rates after 1, 3 and 5 years were 80.2, 53.6 and 19.2%, respectively.ConclusionsAlthough our low rates of postoperative complications and mortality using external Wirsung duct stenting coincides with other more numerous recent series, it is necessary to perform a comparative analysis with other techniques, including more cases, to choose the best reconstruction technique after pancreaticoduodenectomy.  相似文献   
84.
BackgroundSleeve gastrectomy (SG) has become the most prevalent bariatric-metabolic surgical approach in the United States. Its popularity among surgeons and patients is mainly due to a better safety profile and less overall morbidity, with broad benefits from a systemic and metabolic perspective.ObjectiveComprehensively describe the short-term multiorgan metabolic effects of rapid weight loss after SG.SettingAcademic hospital, United States.MethodsWe retrospectively reviewed the charts of patients that underwent SG at our institution between 2012 and 2016. We analyzed the required variables to calculate multiple risk scores, such as cardiovascular, hypertension, and diabetes risk scores. Furthermore, the renal and hepatic functions and the metabolic and hematologic profiles were assessed at 12 months of follow-up.ResultsA total of 1002 patients were included in the analysis. The percentage of excess body mass index loss was, on average, 65% at 12 months of follow-up. We observed a positive cardio-renal-hepatic improvement, demonstrated by a substantial reduction of the 10-year cardiovascular risk. We noticed an improvement of renal function, which was more significant in chronic kidney disease (stage ≥2), and a significant improvement on liver function tests (measured by decreased aspartate aminotransferase and alanine transaminase) at 12 months of follow-up. Our data also show a positive impact on decreasing the risk of developing hypertension and type 2 diabetes. There was a positive impact on the lipid profile, with the exception of low-density lipoprotein.ConclusionThere are significant short-term benefits on multiorgan metabolic parameters after rapid weight loss in severely obese patients undergoing sleeve gastrectomy.  相似文献   
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Summary The genetic polymorphism of transferrin (Tf) was studied in a sample of 385 healthy unrelated subjects of both sexes resident in the province of Cádiz (southern Spain). Isoelectric focusing was carried out in polyacrylamide gels, followed by staining with Coomassie Blue R250. The gene frequencies obtained were as follows: Tf C1, 0.7922; Tf C2, 0.1883; Tf C3, 0.0195.  相似文献   
88.
Electroconvulsive therapy (ECT) was successfully used to treat a patient with large neurosurgical defects of the cranium and small pieces of shrapnel in the zygoma and neck. Other patients with a variety of skull defects have also been treated successfully. Theoretical considerations of current pathway in ECT would suggest an alteration through the brain when the skull is deformed, but this does not appear to affect clinical outcome.  相似文献   
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90.
Summary The need for further information on drug utilization patterns during pregnancy in different countries was assessed by reviewing literature obtained by hand and computer searches for the years 1960–1988.The 13 identified studies showed that pregnant women used an average of 4.7 drugs. The most commonly ingested medications were vitamins and iron preparations (almost all women), analgesics, antiemetics and antacids.However, the important variables taken into account differently in each study, such as date of surveillance, country, size of population, personal habits, and physiopathological and demographic characteristics, may it impossible to construct a comprehensive, detailed, up-to-date picture of drug utilization during pregnancy.The evaluation confirmed the need for systematic permanent surveillance of drug utilization in pregnancy, so as to avoid the use of data based on widely differing contexts, times and methods, in a field where knowledge is often derived from scanty information.This study was supported in part by the National Research Council (CNR, Rome, Italy), Convenzione Farmacologia Clinica  相似文献   
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