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991.
992.
MD Pérez Cárdenas JC Montejo González MP Conde Alonso D Ayuso Murillo AI Fernández Herranz AI Cabrero Cabrero RM Sánchez Fernández 《Canadian Metallurgical Quarterly》1993,8(8):504-509
The main advantages of infusion pumps are their enhanced accuracy and safety in providing enteral nutrition. We proposed to observe pumps reliability in connection with a variety of factors such as the type of pump used, the administration rate and the energy density of the diets used. An experimental design was prepared with two types of enteral nutrition pumps-VP, volumetric pump, and PP, peristaltic pump. The clinical simulation was done by connecting the enteral nutrition equipment to a graduated dosing system, making hourly measurements of the volume infused. The Reliability Index (RI) used was the ratio between the volume infused by the pump and the regulated dose (Vi/Do). Five volumetric pumps (FLEXIFLO COMPANION) and five peristaltic pumps (FLEXIFLO II) were selected at random from a single commercial outlet. Each was used for twenty-three hours, without interruption, to infuse five types of diet with different energy densities (D1:2 Kcal/ml, D2: 1.5 Kcal/ml, D3: 1.25 Kcal/ml, D4: diet with fibre, and D5: reconstituted powder diet) at three different flow rates (40, 80 and 120 ml/h), to provide fifteen experimental conditions with each pump. Reliability was maintained for both types of pump within the margin of error claimed by the manufacturer (+/- 10%) except in the first hour of infusion (RI = 71.4%). Comparison of the overall RI between the two pump types revealed significant differences, with an RI below the reference range for the VP only during hour 23 (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
993.
SX Cai ZL Zhou JC Huang ER Whittemore ZO Egbuwoku Y Lü JE Hawkinson RM Woodward E Weber JF Keana 《Canadian Metallurgical Quarterly》1996,39(17):3248-3255
A series of 1,2,3,4-tetrahydroquinoline-2,3,4-trione 3-oximes (QTOs) was synthesized and evaluated for antagonism of NMDA receptor glycine site. Glycine site affinity was determined using a [3H]DCKA binding assay in rat brain membranes and electrophysiologically in Xenopus oocytes expressing 1a/2C subunits of cloned rat NMDA receptors. Selected compounds were also assayed for antagonism of AMPA receptors in Xenopus oocytes expressing rat brain poly-(A)+RNA. QTOs were prepared by nitrosation of 2,4-quinolinediols. Structure-activity studies indicated that substitutions in the 5-, 6-, and 7-positions increase potency, whereas substitution in the 8-position causes a decrease in potency. Among the derivatives evaluated, 5,6,7-trichloro-QTO was the most potent antagonist with an IC50 of 7 nM in the [3H]DCKA binding assay and a Kb of 1-2 nM for NMDA receptors expressed in Xenopus oocytes. 5,6,7-Trichloro-QTO also had a Kb of 180 nM for AMPA receptors in electrophysiological assays. The SAR of QTOs was compared with the SAR of 1,4-dihydroquinoxaline-2,3-diones (QXs). For compounds with the same benzene ring substitution pattern, QTOs were generally 5-10 times more potent than the corresponding QXs. QTOs represent a new class of inhibitors of the NMDA receptor which, when appropriately substituted, are among the most potent glycine site antagonists known. 相似文献
994.
A Heding R Gill Y Ogawa P De Meyts RM Shymko 《Canadian Metallurgical Quarterly》1996,271(24):13948-13952
Most insulin-like growth factor (IGF) molecules in the circulation are found in a 150-kDa complex containing IGF-binding protein-3 (IGFBP-3) and an acid-labile subunit, which does not itself bind IGF. Affinities (Kd values) between 0.03 and 0.5 nM have been reported for IGF-I/IGFBP-3 binding, but no kinetic data are available. In this study we measured the high affinity binding of unlabeled IGFs and IGF analogues to recombinant unglycosylated IGFBP-3, using a BIAcoretrade mark instrument (Pharmacia Biosensor AB). IGF-I binding showed fast association and slow non-first-order dissociation kinetics, and an equilibrium Kd of 0.23 nM. IGF-II had similar kinetics with slightly higher affinity. Analogues with mutations in the first 3 amino acids of the B-region (des(1-3) IGF-I and long IGF-I) showed 25 and 50 times lower affinity than IGF-I. Replacement of residues 28-37 by Gly-Gly-Gly-Gly or deletion of residues 29-41 in the C-region had little effect on the kinetic parameters, contrasting with the markedly impaired binding of these analogues to the IGF-I receptor. Swapping of the disulfide bridges in IGF-I and the C-region mutants decreased the affinity dramatically for IGFBP-3, primarily by decreasing the association rate. Insulin had approximately 1000 times lower affinity than IGF-I. 相似文献
995.
Scleroderma (SSc) is a disease characterized by skin fibrosis but it is the end-organ effect of microvascular injury and fibrosis that is important prognostically. Pulmonary involvement in SSc patients, either of parenchymal fibrosis and/or pulmonary hypertension, is a major cause of morbidity and mortality. Interstitial lung disease occurs more commonly in patients with diffuse SSc and is associated with a loss of lung volume, as well as a defect of gas exchange. Parenchymal fibrosis may also cause pulmonary hypertension. Isolated pulmonary hypertension occurs exclusively in patients with limited SSc and is detectable by a reduced DCO. The early identification of either manifestation is difficult. Patients may have minimal symptoms, unremarkable physical findings, normal chest radiographs and/or minimally abnormal pulmonary function tests at a time when significant lung pathology is present. It is essential to attempt to identify pulmonary disease early, at a potentially reversible stage. Multiple therapeutic endeavours have yielded only short-term or minimal benefits in symptoms and pulmonary function, and thus a major alteration in SSc pulmonary prognosis has not been achieved. Further study of the pathogenesis of this disease manifestation will be helpful in its earlier identification and intervention. 相似文献
996.
RM Roumen T Hendriks J van der Ven-Jongekrijg GA Nieuwenhuijzen RW Sauerwein JW van der Meer RJ Goris 《Canadian Metallurgical Quarterly》1993,218(6):769-776
OBJECTIVE: This study investigates the course of serum cytokine levels in patients with multiple trauma, patients with a ruptured abdominal aortic aneurysm (AAA), and patients undergoing elective AAA repair and the relationship of these cytokines to the development of adult respiratory distress syndrome (ARDS) and multiple organ failure (MOF). SUMMARY BACKGROUND DATA: Severe tissue trauma, hemorrhagic shock, and ischemia-reperfusion injury are pathophysiologic mechanisms that may result in an excessive uncontrolled activation of inflammatory cells and mediators. This inflammatory response is thought to play a key role in the development of (remote) cell and organ dysfunction, which is the basis of ARDS and MOF. METHODS: The study concerns 28 patients with multiple trauma, 20 patients admitted in shock because of a ruptured AAA, and 18 patients undergoing elective AAA repair. Arterial blood was serially sampled from admission (or at the start of elective operation) to day 13 in the intensive care unit, and the serum concentrations of tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1 beta, and IL-6 were determined. RESULTS: Twenty-two patients died, 15 within 48 hours and 7 after several weeks, as a result of ARDS/MOF. At hospital admission and after 6 hours, these nonsurvivors had significantly higher plasma TNF-alpha and IL-1 beta levels than did the survivors. At the same measuring points, TNF-alpha and IL-1 beta were significantly more elevated in patients with ruptured AAA than in traumatized patients. However, IL-6 was significantly higher in the traumatized patients. In 10 patients, ARDS/MOF developed, and 41 had an uncomplicated course in this respect. Those with ARDS/MOF exhibited significantly different cytokine patterns in the early postinjury phase. TNF-alpha and IL-1 beta levels were higher mainly on the first day of admission; IL-6 concentrations were significantly elevated in patients with ARDS/MOF from the second day onward. The latter cytokine showed a good correlation with the daily MOF score during the whole 2-week observation period. CONCLUSIONS: In the early postinjury phase, higher concentrations of these cytokines are associated, not only with an increased mortality rate, but also with an increased risk for subsequent ARDS and MOF. These data therefore support the concept that these syndromes are caused by an overwhelming autodestructive inflammatory response. 相似文献
997.
RV Cellona GP Walsh TT Fajardo RM Abalos EC dela Cruz L Guido-Villahermosa MV Felicio-Balagon GJ Steenbergen JT Douglas 《Canadian Metallurgical Quarterly》1993,61(2):192-198
An indirect enzyme-linked immunosorbent assay (ELISA) using natural disaccharide octyl bovine serum albumin (ND-O-BSA) as antigen was used in testing leprosy patients, contacts and a normal population in Cebu, The Philippines, from 1985 to 1989. A total of 1413 persons were studied. The results suggested that ELISA reactivity and the bacterial index (BI) correlate in a general way. In multibacillary (MB) leprosy, positivity ranges from 54.2% to 92.3% among patients with a BI of < 2+ to > 4+ on the Ridley scale, with an overall average of 84.5%. Paucibacillary (PB) leprosy patients have a low degree of reactivity, with only 15.0% ELISA positive. The test is more efficient in detecting MB than PB leprosy. The contacts of MB leprosy showed 6.5% positivity; contacts of PB leprosy, 7.0% positivity. The normal population showed 1.7% positive ELISA or 17 per thousand population, which is very much less than that of the household contacts. However, because the normal population is a much larger population than the household contact population in a community, more new leprosy cases would emanate from it. Leprosy workers are concerned about the transmission of the disease to household contacts. However, for the reason stated above, we should be more concerned with the silent spread of the disease to the normal population in the community.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
998.
Coffey Patricia; Leitenberg Harold; Henning Kris; Turner Tonia; Bennett Robert T. 《Canadian Metallurgical Quarterly》1996,64(5):1090
With a community sample of 192 women who had been sexually abused during childhood, the investigators determined if methods of coping in adulthood with the aftermath of child sexual abuse were associated with current symptoms of psychological distress. Multiple regression analyses indicated that disengagement methods of coping with the sexual abuse accounted for unique variance in general psychological distress even after controlling for characteristics of the abuse and methods of coping with other stressors. Disengagement methods of coping were also used more often to deal with the stressful aspects of having been sexually abused than to deal with other stressful events. In contrast, engagement methods of coping were used more often to deal with the other stressors than with sexual abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
In this paper a combined theoretical and experimental study is reported on the process of solidification of a liquid metal droplet by impaction on a cold substrate (splat-quenching). The study is focused on the heat transfer aspects of this process and on the identification of parameters affecting the heat transfer mechanism. To this end, the effect of the droplet impact velocity and temperature, the effect of the substrate material and its initial temperature, and the effect of the thermal contact resistance between the splat and the substrate are investigated. A two-dimensional conduction model accounting for the freezing process in the splat and for the solidification kinetics has predicted reasonably well the trends observed in the experimental part of the study. 相似文献