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731.
Keith Julian R.; Puente Antonio E.; Malcolmson Keri L.; Tartt Shane; Coleman Amy E.; Marks Howard F. Jr. 《Canadian Metallurgical Quarterly》2002,16(3):411
Cognitive decline after cardiopulmonary bypass (CPB) surgery has been a concern since the advent of CPB procedures. A primary focus of many studies on this topic has been to quantify the incidence of post-CPB cognitive impairment. However, studies that have used traditional parametric statistics have generally failed to confirm that long-lasting (–- I month) cognitive declines occur reliably after CPB surgery. For the present study, the authors used a split-plot analysis of variance model that revealed preoperative memory impairments in the CPB patients and new postoperative impairments of attention. The authors discuss the assumptions of, and problems associated with, analysis methods that are often used to quantify the incidence of cognitive impairment following CPB surgery. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
732.
733.
J Marks 《Canadian Metallurgical Quarterly》1996,18(3):345-362
Serological data have been used to address anthropological problems since the turn of the century. These were predominantly problems of two kinds in anthropological systematics: the relations of human populations to one another (racial serology), and the relations of primate species to one another (systematic serology). Though they were the locus of considerable debate about the relative merits of 'genetic' versus 'traditional' data, the serological work had little lasting impact in the field. I attribute this to the fact that the research was carried out largely externally to anthropology, and often interpreted in facile manners. To a large extent the history of this research has been ignored or rewritten following the development of 'molecular anthropology' in the 1960s. To some extent, however, contemporary genetic research in anthropology replays aspects of the serological era. 相似文献
734.
SD Chipman HO Sweet DJ McBride MT Davisson SC Marks AR Shuldiner RJ Wenstrup DW Rowe JR Shapiro 《Canadian Metallurgical Quarterly》1993,90(5):1701-1705
Osteogenesis imperfecta (OI) is a heritable disorder of connective tissue associated with fractures, osteopenia, and short stature. OI results from mutations affecting the pro alpha 1 or pro alpha 2 gene of type I collagen. We describe a strain of mice with a nonlethal recessively inherited mutation (oim) that results in phenotypic and biochemical features that simulate moderate to severe human OI. The phenotype of homozygous oim mice includes skeletal fractures, limb deformities, generalized osteopenia, and small body size. Their femurs are smaller and demonstrate marked cortical thinning and fewer medullary trabeculae than those of wild-type mice. Breeding studies show the mutation is inherited in most crosses as a single recessive gene on chromosome 6, near the murine Cola-2 gene. Biochemical analysis of skin and bone, as well as isolated dermal fibroblast cultures, demonstrate that alpha 1(I) homotrimeric collagen accumulates in these tissues and is secreted by fibroblasts. Short labeling studies in fibroblasts demonstrate an absence of pro alpha 2(I) collagen chains. Nucleotide sequencing of the cDNA encoding the COOH-propeptide reveals a G deletion at pro alpha 2(I) nucleotide 3983; this results in an alteration of the sequence of the last 48 amino acids. The oim mouse will facilitate the study of type I collagen-related skeletal disease. 相似文献
735.
LR Ranganath JM Beety LM Morgan JW Wright R Howland V Marks 《Canadian Metallurgical Quarterly》1996,38(6):916-919
BACKGROUND: Hypersecretion of insulinotropic factors such as glucose dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1(7-36)amide (GLP-1) have been postulated to account for the hyperinsulinaemia of obesity. AIMS: To examine the role of GLP-1 and GIP in obese women and matched controls. SUBJECTS: Six lean and six obese women subjects matched for age. METHODS: The gut hormone, plasma glucose, and serum triglyceride responses were studied over 180 minutes after oral carbohydrate and fat meals. Heparin (10,000 units) was given intravenously at 120 minutes. RESULTS: There was pronounced attenuation of plasma GLP-1 secretion to oral carbohydrate in the obese compared with lean subjects but no such difference in response to oral fat load. There were no differences in the plasma GIP responses to carbohydrate or fat feeding. There was an apparent fall in plasma GLP-1 values in all subjects after administration of heparin. CONCLUSION: Postprandial GLP-1 secretion in response to oral carbohydrate is considerably attenuated in obese subjects. The cause of this attenuation of GLP-1 secretion is not known although we suggest that both this fall and the overall reduction in GLP-1 values in obese subjects may be related to an increase in plasma non-esterified fatty acids. 相似文献
736.
737.
Analysis of the motor component in feeding behaviour of the crayfish enabled to differentiate it into separate fragments with respect to the targets which are reached due to realization of each of these fragments. It is suggested that separate fragments are realized by some functional blocks which are activated from their own receptive zones by trigger mechanisms. With changing the coordinates of food stimulus the whole structure of the behaviour also changes due to the inclusion of additional fragments (locomotions, rearrangement of postures, activation of the claw extremities, etc.). Since this rearrangement favours the animal in reaching its final target, it may be considered as adaptive one. 相似文献
738.
G Brandst?tter IN Marks F Lanza D Kogut B Cobert JP Savitsky W Bender R Labs H Wurzer 《Canadian Metallurgical Quarterly》1995,17(3):467-478
Roxatidine (150 mg, 312 patients) was compared with ranitidine (300 mg, 308 patients) in a randomized, double-blind, parallel-group, 6-week therapeutic study for the treatment of patients with uncomplicated, benign gastric ulcer disease. The study end points (verified by using endoscopy results) were fully healed ulcers at 4 or 6 weeks. The results of roxatidine therapy were comparable to those of ranitidine therapy: healing rates of 52% and 54% at week 4 and 77% and 76% at week 6 were recorded for roxatidine and ranitidine, respectively. The drugs produced comparable reductions in ulcer diameters and decreases in abdominal pain. Adverse events associated with both roxatidine (27%) and ranitidine (28%) were headache, diarrhea, and dizziness; rash was associated in 6 of 8 cases and in only 1 case with roxatidine. In this trial, roxatidine 150 mg once daily was as efficacious and safe as ranitidine 300 mg once daily for treatment of patients with uncomplicated, benign gastric ulcer disease. 相似文献
739.
Marks Mitchell L.; Mirvis Philip H.; Hackett Edward J.; Grady James F. 《Canadian Metallurgical Quarterly》1986,71(1):61
To assess the impact of a quality circle (QC) program at a manufacturing firm, 46 participants (mean age 44 yrs) and 46 nonparticipants (mean age 40 yrs) were surveyed before and after implementation of the QC program. Multiple regression analysis revealed a positive relation between QC participation and changes in quality of work life (QWL) perceptions in areas directly involved in QC activities but not in more general work life areas. Given that participants' QWL scores tended not to change and nonparticipants tended to report decreases in QWL from before to after the QC program implementation, the results suggest that QC involvement acted more to provide social support to buffer participants from negative contextual factors than to enhance equality of work life. Organizational records also were assessed from 6 mo before to 24 mo after adoption of the QC program and showed that QC participation led to improvements in employee productivity and absenteeism rates. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
740.
There were no effects in commercial broilers after the long term ingesting of Fusarium-infected corn supplying 1, 10, and 30 p.p.m. zearalenone (F-2) in diets. Average gain and feed conversion were similar in all treatment groups. In the first feeding trial the average body weights were higher for males than for females, but the differences were not significant. Purified F-2, 30 P.P.M., was fed to broilers and no chronic effects were observed. Differences in mean body weights, between dietary treatments in the two Japanese quail lines were small and not significant after 4 weeks on diets containing 0, 10, and 25 p.p.m. F-2 from Fusarium infected corn. 相似文献