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41.
James Rodgers Kaye Wolf Norm Willis Don Hamilton Ralph Ledbetter Curtis Stewart 《Color research and application》1994,19(5):322-331
A multiplant Quality Improvement Team [QIT] was firmed to develop and implement an evaluation program for various color measurement .systems as potential replacements for the then-current aging systems. The emphasis qf this article is the analytical methodology utilized to evaluate the various color systems. The evaluation program consisted cf two phases. Phase I was a general overview/review of several systems, while Phase II was an extensive internal comparative evaluation measurement systems. These were Milton-Roy's ColorMate HDS, HunterLab's Ultrascan, Datacolor's CS-5, and BYK-Gardner's The Color Sphere [TCS]. The main comparison criteria were interinstrument agreement [agreement between two instruments ofthe same system], user-friendly software and computer interface capability, vendor amenability to a long-term logistical and maintenance relationship, and price. All systems were evaluated by duplicate measurements on various color tiles, yarns, and polymer flakes-over 1600 measurements on each system. The systems were compared with an instrument matrix, a decision matrix, and a product matrix. The instrument matrix was a comparison qfinstrument parameters, software/math treatments, and economics. The decision matrix was a forced ranking of each system by each criteria category [1–4 scale, with 1 representing the best and 4 representing the worst]. The product matrix accentuated the relative importance ofone criterion category over another by multiplying the forced ranking by the criticality of the category. The criticality of a given category wus determined by consensus within the QIT. Thr combination qf the three matrices allowed the evaluator[.s] t o select the color rneasuremmt system that best satixfied the color measurement needs and requirements of their facility and their products. For this evaluation, all ofthe evaluated systems were superior to the then-current agingsystems. As a result of this methodology, one instrument emerged as clearly superior. © 1994 John Wrley & Sons, Inc. 相似文献
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BACKGROUND: Platelet-activating factor (PAF) is a bioactive phospholipid which is a potent hypotensive agent. To investigate the role of PAF in renovascular hypertension, we determined the PAF concentration and its production level assessed by the activity of cholinephosphotransferase (CPT) in renal tissue and examined the effect of a PAF antagonist on the mean arterial pressure (MAP) in control and two-kidney with one clipped (2K1C) hypertensive rats. MATERIALS AND METHODS: The concentration of PAF and CPT in the renal medulla and cortex were determined by radioassay. Also, the effect of a PAF antagonist, CV-6209, on MAP was also examined in both 2K1C hypertensive and normal control rats. RESULTS: The PAF concentration and CPT activity were significantly higher in the medulla than in the cortex in both 2K1C hypertensive and normal control rats, and both values in the medulla were also significantly higher in the clipped kidney than in the contralateral unclipped kidney or in control rat kidneys. We also observed a significant negative correlation between the PAF concentration in the medulla, and the medulla weight in the clipped kidney of 2K1C hypertensive rats. Infusion of the PAF antagonist, CV-6209, did not affect MAP in 2K1C hypertensive rats, but was significantly increased (P < 0.05) in control rats. CONCLUSIONS: These findings suggest that PAF, whose production is induced by renal ischemia due to renal artery stenosis, plays an important role in the renomedullary vasodepressor system, but the effect of PAF as a vasodilator in the peripheral vessels is limited in 2K1C hypertension. 相似文献
44.
M Chopineau N Martinat C Troispoux H Marichatou Y Combarnous F Stewart F Guillou 《Canadian Metallurgical Quarterly》1997,152(3):371-377
Horse (Equus caballus) luteinizing hormone (eLH) and chorionic gonadotrophin (eCG), which have the same amino acid sequence, are unusual in that, although they express only LH activity in equids, they express dual LH and FSH activities in all other species tested. Donkey (Equus asinus) LH (dkLH) and CG (dkCG), which also share an identical peptide backbone, have been less well characterized and conflicting results concerning their FSH activity in heterologous species have appeared in the literature. In order to assess and compare the intrinsic LH and FSH activities of the horse and donkey LHs in heterologous species, recombinant eLH (r.eLH/CG) and recombinant dkLH (r.dkLH/CG) were expressed, for the first time, in COS-7 cells. Their LH activities were assessed in a rat Leydig cell bioassay, and their FSH activities were estimated in a bioassay using Y1 cells stably expressing the human FSH receptor. Human CG (hCG) was expressed (r.hCG) and analysed in the same system. The results showed that, whereas r.dkLH/CG was about twice as active as r.eLH/CG in the LH bioassay, it was five times less active than r.eLH/CG in the FSH bioassay; r.hCG was about three times less active than r.eLH/CG in the LH bioassay but was completely inactive in the FSH bioassay. These results confirm that dkLH/CG possesses significant FSH activity in heterologous species that is not attributable to contamination with FSH. 相似文献
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46.
JF McCarthy DJ Cook MG Massad Y Sano KJ O''Malley NR Ratliff RW Stewart NG Smedira RC Starling JB Young PM McCarthy 《Canadian Metallurgical Quarterly》1998,14(2):197-200
28 isolates of canine parvovirus type-2 (CPV-2) were obtained from dogs with hemorrhagic gastroenteritis in Italy. The antigenic structure of CPV-2 isolates was characterized, using four discriminating monoclonal antibodies. In addition, four vaccinal strains were examined. Similar to reports from Australia and the United Kingdom, a much higher prevalence of CPV-2a (25/28 isolates) was observed than the other variant type, CPV-2b (3/28 isolates). DNA fragments (2.2 kbp) of representative strains of CPV-2, CPV-2a and CPV-2b were amplified by the polymerase chain reaction (PCR) and the products were digested by the restriction enzymes (RE) RsaI, HpaII, HindIII and PvuII. The RvaI enzyme allows the differentiation of CPV-2 from CPV-2a and CPV-2b. 相似文献
47.
DF Zatzick DS Weiss CR Marmar TJ Metzler K Wells JM Golding A Stewart WE Schlenger WS Browner 《Canadian Metallurgical Quarterly》1997,162(10):661-665
OBJECTIVE: This investigation assessed whether current post-traumatic stress disorder (PTSD) was associated with impaired functioning in a nationally representative sample of female Vietnam veterans. METHODS: Logistic models were used to determine the association between PTSD and outcome while adjusting for demographic characteristics and medical and psychiatric co-morbidities. RESULTS: PTSD was associated with significantly elevated odds of poorer functioning in five of the six outcome domains; only the association between perpetration of violence in the past year and PTSD did not achieve statistical significance. After adjusting for demographics and medical and psychiatric co-morbidities, PTSD remained associated with significantly elevated odds of bed days, poorer physical health, and currently not working. CONCLUSIONS: Among female Vietnam veterans PTSD is associated with a broad profile of functional impairment. The significantly increased odds of impaired functioning and diminished quality of life suggest that PTSD may be the core problem of the set of problems afflicting female Vietnam veterans. 相似文献
48.
Meeting a person with AIDS in the classroom was evaluated to determine if it had an impact on students' perceived susceptibility to HIV infection and attitudes toward persons with AIDS. The meeting was incorporated into the Grade 9 AIDS education program of a school district in Nova Scotia. Four schools participated in this study. Two schools were randomly assigned to the treatment group, which met the person with AIDS, and the remaining two schools formed the comparison group. Measures of the two attitudinal variables were collected using a self-report questionnaire that was administered both prior to and two weeks after the educational intervention. Meeting a person with AIDS in the classroom had no measurable impact on students perceived susceptibility to HIV infection nor on their attitudes toward persons with AIDS. Suggestions for using the educational intervention more effectively and for further research are made. 相似文献
49.
Twenty mothers of preterm babies who had survived to 1 year old, were matched for age and parity of the mother and time of birth of the baby, with 20 mothers delivering fullterm. Bone mineral, body composition and anthropometric measurements were obtained for each mother and analysed using paired t-tests. The only significant difference (P < 0.01) between the groups was a lower fat-free mass in the preterm mothers calculated from skinfold thickness measurements. 相似文献
50.
Statewide crash data bases from nine states were subjected to time series analyses to detect changes in injuries associated with onset of seat belt laws in the respective states. In each of 18 analyses involving drivers covered by the law observed casualties were below the number forecast on the basis of prior experience and assuming that no law had been enacted. In the case of others, not covered by the law, observed injuries were equally often above or below forecast. Relative to covered drivers not only were the numbers below forecast, but in 12 of the 18 instances there was a statistically significant indication of an abrupt decrease the month the law began. 相似文献