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201.
Summary Glucose was infused into anaesthetized dogs before and after pancreatectomy. In the diabetics blood glucose was regulated first by closed-loop and then by open-loop insulin delivery schemes. Insulin requirements for the latter were determined by resolving the former into a sequence of 3 different infusion rates: during the baseline and recovery periods, basal insulin was delivered at 0.37±0.02 mU/kg/min, while during the 60 min glucose infusion (10 mg/kg/min) there was an 8 min infusion at 4.96±0.37 mU/kg/min and a 52 min component at 1.85±0.08 mU/kg/min. With the open-loop method under these highly standardized conditions glycaemia was similar to normal controls but IRI levels were significantly higher, 13.5 vs 8.0 U/ml (p<0.05) in the baseline and recovery periods and 74 vs 25 U/ml (p<0.05) during the glucose infusion. It was concluded that: constant normogly-caemia can be maintained in the basal state by a constant rate of peripheral insulin delivery but at rates resulting in peripheral hyperinsulinaemia; the glycaemic response to glucose infusion can be normalized by a two component waveform of insulin delivery; and the closed-loop method can serve as a useful guide in determining insulin requirements. 相似文献
202.
Summary This study characterizes the glycaemic and insulin responses of a group of 5 anaesthetized dogs to a portal glucose infusion of 10 mg/kg/min before and after pancreatectomy. Insulin was administered intraportally to the pancreatectomized dogs according to a simple preprogrammed waveform composed of a constant basal rate of 0.35±0.02 mU/kg/min which was increased to 2.00mU/kg/min at the time of the 60 minute glucose challenge. When this square waveform was applied the glycaemic response was similar to that seen in the normal controls in the baseline and challenge periods. Blood glucose concentration differed significantly (p<0.05) only from 20 to 100 minutes after the end of the challenge when it was higher by 20±1 mg/dl. Insulin levels were not significantly different from controls. It may be concluded that normoglycaemia and normoinsulinaemia can be maintained by a simple constant rate of portal insulin delivery while the blood glucose response to a glucose infusion can be ostensibly normalized without hyperinsulinaemia simply by enhancing insulin delivery during the challenge. The feasibility of this approach implies that with further development of the preprogrammed waveforms and with a greater understanding of their characteristics portable insulin delivery systems may be realized which accomodate more physiological challenges. The portal route for insulin delivery may however be necessary if peripheral hyperinsulinism is inappropriate. 相似文献
203.
V A Rosetti B M Thompson J Miller J R Mateer C Aprahamian 《Annals of emergency medicine》1985,14(9):885-888
Substantial difficulties can be encountered when establishing rapid intravascular access in critically ill children. The historic technique of tibial intraosseous infusion is presented as an alternate intravenous route in children less than 3 years old. Review of the literature reveals this technique to be a rapid, reliable method with an acceptably low complication rate. Substances absorbed through the marrow, flow rates, technical difficulties, and complications are discussed. 相似文献
204.
目的:探究静脉用药调配中心(PIVAS)优化院内感染控制管理对患者静脉输液质量及降低医院感染率的影响。方法:抽取2015年1月—2016年12月间PIVAS 1586例患者资料(优化管理前);另抽取2017年1月—2019年1月实施优化管理后的1865例患者资料(优化管理后);优化管理前后PIVAS工作人员均为25名;比较优化管理前后静脉输液质量及医院感染率的差异。结果:与优化管理前相比,优化管理后化疗药物的包装、输液配制质量及操作台环境的满意度均较高(P<0.05),院内感染发生率低于优化管理前(P<0.05)。结论:PIVAS实施优化院内感染控制管理,有效提高了静脉输液质量,遏制了院内感染的发生,保证了患者用药的安全性。 相似文献
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206.
D. Santos-García M.J. Catalán V. Puente F. Valldeoriola I. Regidor P. Mir J. Matías-Arbelo J.C. Parra F. Grandas 《Neurología (Barcelona, Spain)》2021,36(2):101-111
ObjectivesTo compare the characteristics of patients undergoing treatment with continuous intestinal infusion of levodopa-carbidopa (CIILC) for advanced Parkinson's disease and the data on the effectiveness and safety of CIILC in the different autonomous communities (AC) of Spain.MethodsA retrospective, longitudinal, observational study was carried out into 177 patients from 11 CAs who underwent CIILC between January 2006 and December 2011. We analysed data on patients’ clinical and demographic characteristics, variables related to effectiveness (changes in off time/on time with or without disabling dyskinesia; changes in Hoehn and Yahr scale and Unified Parkinson's Disease Rating Scale scores; non-motor symptoms; and Clinical Global Impression scale scores) and safety (adverse events), and the rate of CIILC discontinuation.ResultsSignificant differences were observed between CAs for several baseline variables: duration of disease progression prior to CIILC onset, off time (34.9-59.7%) and on time (2.6-48.0%; with or without disabling dyskinesia), Hoehn and Yahr score during on time, Unified Parkinson's Disease Rating Scale-III score during both on and off time, presence of ≥ 4 motor symptoms, and CIILC dose. Significant differences were observed during follow-up (> 24 months in 9 of the 11 CAs studied) for the percentage of off time and on time without disabling dyskinesia, adverse events frequency, and Clinical Global Impression scores. The rate of CIILC discontinuation was between 20-40% in 9 CAs (78 and 80% in remaining 2 CAs).ConclusionsThis study reveals a marked variability between CAs in terms of patient selection and CIILC safety and effectiveness. These results may have been influenced by patients’ baseline characteristics, the availability of multidisciplinary teams, and clinical experience. 相似文献
207.
ObjectivesTo assess energy dissipation capacities and surface damping abilities of different CAD/CAM restorative materials (CRMs) to characterize stress resistance during load peaks.MethodsUsing instrumented indentation testing (IIT), Martens hardness (HM) together with its elastic (ηIT) and plastic index (ηITdis) and Leeb hardness (HLD) together with its deduced energy dissipation (HLDdis) were determined for eight ceramic, eight composite, and four polymer-based materials as well as three metals. The results were compared to those of bovine enamel. Ten indentations per material were performed at room temperature (23 ± 1 °C) on two separate specimens (12.0 × 12.0 × 3.5 mm3) after water storage (24 h; 37.0 ± 1.0 °C). Hardness parameters were recorded, and data were analyzed with one-way MANOVA (Games-Howell post hoc tests, α = 0.05). Correlations between different parameters were tested (Pearson, α = 0.05).ResultsIndependently determined HLDdis, and ηITdis values substantiated different energy dissipation characteristics of CRM, whereby a strong correlation was observed for the two datasets (r = 0.956, p = 0.011). Ceramics had the significantly lowest values (p < 0.001) while both parameters revealed the highest surface damping effects for metals (p < 0.001), followed in both cases by bovine enamel. Energy dissipation of polymer and composite CRM was in between ceramics and bovine enamel (p < 0.001), whereas only for HLDdis did both show no significant difference (p > 0.05).SignificancePromising new HLDdis and ηITdis data allow a reliable differentiation of energy dissipation and surface damping capacities of CRMs. Previously published rankings of edge chipping and loss tangent results were perfectly reproduced, especially by HLDdis. 相似文献
208.
Maria José Azevedo de Brito Fábio Xerfan Nahas Neli Regina Siqueira Ortega Táki Athanássios Cordás Gal Moreira Dini Miguel Sabino Neto Lydia Masako Ferreira 《International journal of medical informatics》2013,82(9):844-853
PurposeTo develop a fuzzy linguistic model to quantify the level of distress of patients seeking cosmetic surgery. Body dysmorphic disorder (BDD) is a mental condition related to body image relatively common among cosmetic surgery patients; it is difficult to diagnose and is a significant cause of morbidity and mortality. Fuzzy cognitive maps are an efficient tool based on human knowledge and experience that can handle uncertainty in identifying or grading BDD symptoms and the degree of body image dissatisfaction. Individuals who seek cosmetic procedures suffer from some degree of dissatisfaction with appearance.MethodsA fuzzy model was developed to measure distress levels in cosmetic surgery patients based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), diagnostic criterion B for BDD. We studied 288 patients of both sexes seeking abdominoplasty, rhinoplasty, or rhytidoplasty in a university hospital.ResultsPatient distress ranged from “none” to “severe” (range = 7.5–31.6; cutoff point = 18; area under the ROC curve = 0.923). There was a significant agreement between the fuzzy model and DSM-IV criterion B (kappa = 0.805; p < 0.001).ConclusionThe fuzzy model measured distress levels with good accuracy, indicating that it can be used as a screening tool in cosmetic surgery and psychiatric practice. 相似文献
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210.