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The development of markers for the Big-Five factor structure. 总被引:2,自引:0,他引:2
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V Kamath CN Jones JC Yip BB Varasteh AH Cincotta GM Reaven YD Chen 《Canadian Metallurgical Quarterly》1997,20(11):1697-1701
OBJECTIVE: To assess the effect on various aspects of carbohydrate and lipid metabolism of administering a quick-release formulation of bromocriptine (Ergoset) to obese, nondiabetic, hyperinsulinemic women. RESEARCH DESIGN AND METHODS: Hourly concentrations of prolactin, glucose, insulin, free fatty acid (FFA), and triglyceride were measured for 24 h before and after approximately 8 weeks of treatment with Ergoset. In addition, fasting lipid and lipoprotein concentrations and the steady-state plasma glucose (SSPG) concentration in response to a continuous infusion of somatostatin, insulin, and glucose were determined before and after Ergoset administration. RESULTS: Circulating prolactin concentrations were dramatically decreased (P < 0.001) following treatment, associated with a significant fall (P < 0.05) in 24-h-long plasma glucose, FFA, and triglyceride concentrations. Neither circulating plasma insulin concentrations nor the ability of insulin to mediate glucose disposal changed with treatment. Finally, fasting total cholesterol fell (P < 0.05) and the ratio of total to HDL cholesterol decreased (P = 0.06) in association with Ergoset treatment. CONCLUSIONS: The fact that significant metabolic improvement was seen in the obese nondiabetic hyperinsulinemic women studied suggests that Ergoset could be of therapeutic benefit in clinical conditions of hyperglycemia and/or dyslipidemia. 相似文献
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J. Jancar A. T. Dibenedetto Y. Hadziinikolau A. J. Goldberg A. Dianselmo 《Journal of materials science. Materials in medicine》1994,5(4):214-218
The mechanical properties of an orthodontic wire pultruded from S2-glass-reinforced polyethyleneterephthalate glycol (PETG) were measured using two experimental devices simulating clinical conditions. A comparison of moduli measured in the clinically relevant devices with those measured in a standard flexural test reveals that data obtained using small cross-section, short span length clinical specimens require corrections associated with clamping and shearing effects. The clamping effect dominates and is caused by the softening of the material near the clamps. The shear effect becomes important at high fibre volume fractions and small span/thickness ratios. With adoption of these corrections, good agreement between moduli calculated using rule of mixtures and those measured in clinical tests is achieved. The analytical base developed for prediction of the stiffness of the orthodontic wire for different span/thickness ratios improves the procedure for design of dental appliances. 相似文献
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OBJECTIVE: The authors report the use of multiple implanted intraspinal port and catheter systems per test animal to study the in vivo functional characteristics and reliability of a new implantable spinal drug delivery port system. METHODS: Four ewes were each implanted with two epidural and one subarachnoid silicone elastomer catheters at the lumbar level. Each catheter was connected in series to one of three Therex filtered spinal delivery ports implanted subcutaneously in a similar grid pattern in each ewe to facilitate percutaneous identification. Saline (2 ml) was injected 3 times weekly in each port. The ease of injection and behavioral responses were recorded for 207-213 days of implantation until sacrifice/necropsy. RESULTS: All ports functioned reliably during the study. However, injection through two of the four subarachnoid catheters resulted in behavioral withdrawal responses intermittently. This behavioral pattern was much less common after epidural port injections. All four subarachnoid and four of eight epidural port and catheter systems were tested with local anesthetic just before sacrifice. Motor block was observed in three of four subarachnoid and three of four epidural port and catheter systems tested. Integrity of the other four epidural ports was tested by injection of methylene blue at sacrifice. This dye did not distribute in the epidural space in one of the latter four epidural ports (not local anesthetic tested) because of a concentric fibrotic reaction about the catheter. Similar fibrotic reactions surrounded the catheters that failed a functional test with local anesthetic. CONCLUSIONS: The implantable intraspinal port system tested functions reliably under repetitive percutaneous access. However, filtering such ports, though desirable to prevent entry of debris into the spinal canal, did not eliminate pericatheter chronic subarachnoid and epidural reaction. The number of test animals required to test 12 ports chronically was reduced by two-thirds without undue trauma to the individual test subject. Chronic percutaneous injection of an implanted subarachnoid system is feasible but may be associated with behavioral effects similar to that seen with chronic epidural systems. Fibrosis around chronic silicone catheters limited functional utility in one-fourth of the implanted test systems. Further study of the potential reactivity of chronic epidural and subarachnoid catheters is indicated. 相似文献
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Ockene Judith K.; Kristeller Jean; Pbert Lori; Hebert James R.; Luippold Rose; Goldberg Robert J.; Landon Joan; Kalan Kathryn 《Canadian Metallurgical Quarterly》1994,13(3):278
Patterns of smoking cessation using 6- and 12-mo follow-up data are reported for 1,261 primary care patients randomized to 3 physician-delivered smoking interventions: advice only (AO), counseling (CI), and counseling plus availability of nicotine-containing gum (CI?+?NCG). One-week point-prevalence cessation rates at 12 mo did not differ among the interventions: AO (15.2%), CI (12.9%) and CI?+?NCG (16.7%). However, maintained cessation rates (abstinent at both 6 and 12 mo) increased with intervention intensity: AO (6.0%), CI (7.8%), and CI?+?NCG (10.0%): Test of trend χ–2?=?5.06, p?=?.02. CI?+?NCG was significantly higher than AO (p?=?.02). The findings support the following conclusions: Brief physician delivered intervention with availability of nicotine-containing gum can have a beneficial long-term effect on smoking cessation, and cohort data as well as point-prevalence rates are important when assessing the long-term impact of lifestyle interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Revisiting neighbourhood change from a Canadian perspective: Some supporting evidence from Vancouver
This paper argues that the several models of neighbourhood change developed in the United States are generally not applicable to Canadian cities due to differences in urban form, socioeconomic characteristics, and a host of institutional factors. A simple model is presented which extends the arbitrage model of neighbourhood dynamics. Several hypotheses are advanced and then tested on a data base covering three Vancouver, B.C. neighbourhoods from 1955 to 1981 by estimating several hedonic price equations. The hypotheses receive partial support. Implications for policymakers are then discussed.We wish to thank Jim Fitzsimmons and Judy Fountain for their computer assistance and the British Columbia Assessment Authority for providing us with data. Helpful comments on an earlier version of this paper were provided by Lawrence Jones and Douglas Diamond. We also like to acknowledge the financial support of the Canada Mortgage and Housing Corporation, the Real Estate Council of British Columbia, the University of British Columbia and the British Columbia Youth Employment Program. 相似文献