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71.
This article presents advances in the methodology of rapid various probe configurations comparison for the five-axis, tilting-head machine tools in conjunction with master artifacts. The research was performed in a direct context of automated machining of large, complex jet engine cases made from 17-4PH and 321 stainless steel materials. The aim of the study was to investigate whether all probe configurations have comparable measurement capability for use in manufacturing environment conditions. Based on the preliminary stage of the study, the T1 main straight probe achieved acceptable results of repeatability and reproducibility, lower than 10%, except for the reference diameter measurement of MT#2, where 15.4% R&R was achieved, conditionally accepted. For the straight probe configuration, error lower than 10 μm was achieved for the true position measurement and error ±10 μm for the reference diameter measurement, in relation to the vertical and horizontal head position, with the exception of the T9 and T5 MT#2 probe configuration, where higher error was noticed. The obtained results of the T5 MT#2 and T9 probes were supplemented with additional tests, which are also included. For the custom styli probes, the T4 and T6 configurations, unacceptable error, higher than 0.30 mm, was observed for the Y axis position. Depending on the shop floor and machine tool condition, variability of the results was also observed. Hence, the collected data and research helped to determine the mutual measurement errors and determine the application limitations of probes for an adaptive process flow.  相似文献   
72.
Biglycan, a proteoglycan component of extracellular matrix, has been suspected to contribute to the development of atherosclerosis, but overexpression of biglycan in transgenic mice has been shown to induce cardioprotective genes including nitric oxide (NO) synthases in the heart. Therefore, here we hypothesized if exogenous administration of biglycan exerts cytoprotection. Primary cardiomyocytes from neonatal rats were subjected to 150 min hypoxia and 2 h reoxygenation. Mortality of cardiomyocytes was dose-dependently attenuated by pretreatment with 1-100 nM biglycan. Biglycan enhanced eNOS mRNA and protein, and significantly increased NO content of cardiomyocytes. The NO synthase inhibitor l-nitro-arginine-methyl-ester significantly attenuated the cytoprotective effect of biglycan. This is the first demonstration that biglycan leads to cytoprotection against hypoxia/reoxygenation injury, and that this phenomenon is partially mediated by an NO-dependent mechanism.  相似文献   
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The effects of low molecular weight lymphokine-derived oligopeptides (LK-OPs) on PMNLs effector functions and receptor mediated biochemical events were studied in the case of healthy young and aged subjects. In the case of young subjects the low mol. wt. LK-OPs stimulated the Fc gamma receptor-mediated effector functions of PMNLs, whereas an inhibition was observed in PMNLs of the elderly (extracellular cytotoxicity and intracellular killing). The underlying biochemical events, induced by low mol. wt. LK-OPs stimulation, were also investigated. In PMNLs of young subjects the oxidative metabolism was stimulated (enhanced O2 consumption, O2 and H2O2 production) by low mol. wt. LK-OPs, while in elderly subjects it was inhibited. The cyclic nucleotides regulating the Fc gamma receptor mediated effector functions and the oxygen radicals formation showed an altered dynamic response under low mol. wt. LK-OPs stimulation with aging i.e. the cGMP level could not be changed at all. Our results suggest that low mol. wt. LK-OPs induced inhibition of Fc gamma receptor mediated effector functions with aging could be partly explained by an altered post receptorial coupling switch and as a consequence the lymphokines could not play their role of immunomodulators further impairing the altered immune response with aging.  相似文献   
74.
The aim of this study was to investigate, by using chromosome aberration (CA) and sister chromatid exchange (SCE) tests, whether or not the workers employed in the Iskenderun (Turkey) iron and steel factory have any genotoxic risk. The CA and the SCE were investigated in 48 males employed in a coke ovens unit and 8 males employed in a product side unit of the factory and in control groups. The frequency of CA was higher while the frequency of the SCE was not in all the smoker-nonsmoker workers than in smoker-nonsmoker control groups. In addition, there was no significant decrease in the RI, while the MI was significantly lower than in the controls. .  相似文献   
75.
OBJECTIVES: To evaluate perinatal management and neurological outcome in a group of infants born with Rhesus fetomaternal allo-immunization. PATIENTS AND METHODS: Between 1 January and 31 December 2005, all newborns admitted to neonatal unit of Rouen tertiary centre for Rhesus hemolytic disease were included in a retrospective study and divided in two groups. The newborns who were treated with intrauterine transfusion are in the group 1 and those who needed only postnatal treatment in the group 2. In each case, were considered antenatal management (ultrasonographic data, middle cerebral artery peak systolic velocity, intrauterine transfusion), postnatal treatment (phototherapy, exchange transfusion, transfusion requirements) and neurological outcome. RESULTS: Among 42 cases of Rhesus allo-immunization observed in six years, 28 newborns (67%) were admitted for neonatal cares. No case of fetal hydrops was noted. But 16/28 (57%) were preterm with a median term of 35 weeks gestation (32-36 weeks). In group 1 of six infants who had received intrauterine transfusion (IUT), only one (17%) needed postnatal exchange transfusion, and all six received one to three blood transfusions after their birth. In group 2 of 22 infants who did not receive IUT, 6/22 (27%) needed postnatal exchange and 18/22 (82%) of them received one to four blood transfusions. Phototherapy duration and albumin requirements were similar in both groups. Three deaths occurred, one due to necrotizing enterocolitis and the other two later on due to sudden infant death and fulminant meningococcemia. Neurological outcome of the remaining 25 children was normal. DISCUSSION AND CONCLUSION: Rhesus alloimmunization remain a situation at risk. Neonatal clinical presentation is less severe than previously described due to improvement in antenatal management. Infants required less postnatal exchange transfusion when they received intrauterine transfusion but more frequent blood transfusions.  相似文献   
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Accurate evaluation of patients' psychotic state is essential to decrease psychotic symptoms and protect the patient and others. The aim of this paper is to conduct a literature review in order to access the utility, reliability and validity of current rating scales that are purported to measure psychotic acuity of inpatient population. A search of a number of electronic databases was undertaken to retrieve potential articles that focus on the measurement of acute psychosis. We identified some conceptual and theoretical problems when using a scale that is monitoring the progress of discharge and assesses the outcome of treatments. The findings revealed a difficulty in finding a commonly agreed definition of acute psychosis and a problem of obtaining frequent measures, and the frequency of measurement and fluctuation in psychosis. The most dominant scales in assessing psychosis were reviewed: the Global Assessment of Functioning Scale, the Brief Psychiatric Rating Scale and the Positive and Negative Symptom Scale. Several issues related to the scales' inter-rater reliability and construct validity remain unexplored. None of these scales addressed the conceptual and theoretical problems that we identified. A new scale that will measure acuity of symptoms in inpatient settings needs to be created.  相似文献   
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