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61.
A Smith J McPherson M Taylor A Mason S Carney A Gillies 《Canadian Metallurgical Quarterly》1997,11(12):783-788
It has been suggested that long term treatment with calcium antagonist drugs might inhibit platelet function and lead to an anti-atheromatous effect. However recent data have also suggested that such an effect might increase mortality due to an increased incidence of gastrointestinal bleeding. We identified 43 subjects from general practice with uncomplicated mild to moderate hypertension to compare the effects of the calcium antagonist isradipine with that of the beta-blocker atenolol on platelet function, plasma beta-thromboglobulin levels, fibrinolysis, and serum lipids in a randomised double-blind parallel group study. After careful evaluation to exclude concomitant aspirin use, only 24 subjects were eligible to enter the study. While isradipine and atenolol produced comparable and clinically significant falls in blood pressure (167 +/- 2/102 +/- 1 to 153 +/- 3/91 +/- 2 mm Hg, and 165 +/- 2/101 +/- 1 to 156 +/- 4/91 +/- 2 mm Hg, respectively), neither drug produced a detectable effect on ex vivo platelet aggregation, platelet retention, or thromboxane generation with adrenaline, collagen, adenosine-di-phosphate, or platelet activating factor. However a decrease in plasma beta-thromboglobulin levels was observed which reached statistical significance (P < 0.05) after 12 weeks treatment in the isradipine but not the atenolol group. A 39% reduction with isradipine compared with 34% following atenolol treatment. Euglobulin clot lysis time was not altered by either drug. Serum cholesterol concentrations were also unaltered by drug treatment. Therapeutic doses of the calcium antagonist isradipine may produce a minor indirect effect on platelet function after several weeks of treatment. However, this is of doubtful clinical importance and may simply reflect an effect of lowered blood pressure on platelet function. 相似文献
62.
Describes the main features of professional psychology in Europe, focusing on its professional associations, legal status and definitions, training, forms of employment, and roles and methods. As a reflection of the political, economic, cultural, and social diversity of Europe, significant differences have developed in professional psychology as practiced in the various countries. However, recent factors encouraging closer cooperation include the need for mutual support, political influences, and the programs of the World Health Organization. To assist communication and cooperation, the European Federation of Professional Psychologists Associations has recently been founded, with which 19 national associations are currently affiliated. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
Q Lin H Luo F Mokler AL Beets KR Ambrose DW McPherson J Kropp FF Knapp 《Canadian Metallurgical Quarterly》1997,38(9):1434-1441
Radioiodinated 3(R)-(+)- and 3(S)-(-)-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) were prepared and evaluated in rats to investigate the effects of absolute configuration of the 3(beta)-methyl group on myocardial uptake and release kinetics. METHODS: The 3(R)-(+)-BMIPP analog was synthesized by initial acylation of a thiophene template with the acid chloride of ethyl 3(R)-methylglutarate. 3(S)-(-)-BMIPP was obtained by separation from the mixture of diastereomeric amides prepared from reaction of the acid chloride of racemic BMIPP with the S-(-)-alpha-methylbenzylamine. The amide of synthetic 3(R)-BMIPP prepared from S-(-)-alpha-methylbenzylamine was identical to the chromatographically more polar isomer. Free acids were obtained by acid hydrolysis of the amides, fully characterized and then converted to the radioiodinated BMIPP isomers. RESULTS: Biodistribution studies in rats with the dual-labeled [(131)I]-3(S)-BMIPP/[(125)I]-3(R)-BMIPP mixture demonstrated greater myocardial uptake of 3(R)-BMIPP compared with the 3(S)-BMIPP isomer [60 min: 3(R)-BMIPP = 4.37 %ID/g; 3(S)-BMIPP = 3.44; p < 0.05; 180 min, 2.31 and 1.78 %ID/G, respectively, p < 0.01], although both isomers had similar myocardial washout curves (5-180 min). Percent ID/g values for other tissues which were examined (blood, lungs, thyroid) were similar. CONCLUSION: Higher myocardial uptake of the 3(R)-BMIPP isomer observed in these animal studies may suggest differences in carrier-mediated myocyte uptake of the two isomers. These studies suggest that [(123)I]-3(R)-BMIPP is a candidate for clinical evaluation and may show greater myocardial uptake than the 3(S)-BMIPP isomer and may thus require reduced injected dose. 相似文献
64.
BACKGROUND & AIMS: Despite the high prevalence of the hyperplastic polyp, little is known about its etiology. The aim of this study was to assess the relationship between diet and other lifestyle factors and the presence of colorectal hyperplastic polyps. METHODS: Information on diet and other known or suspected risk factors for colorectal cancer or adenoma was collected among 81 subjects with hyperplastic polyps and 480 controls. RESULTS: The multivariate-adjusted odds ratio (OR) for hyperplastic polyps for individuals in the upper vs. the lower quartile was 0.30 (95% confidence interval [CI], 0.10-0.88) for dietary fiber, 0.32 (95% CI, 0.11-0.96) for dietary calcium, 0.90 (95% CI, 0.27-2.95) for total fat, and 2.02 (95% CI, 1.05-3.91) for alcohol consumption. Compared with individuals in the lower category, those in the upper category of body mass index had a higher risk for hyperplastic polyps (OR, 4.50; 95% CI, 1.84-10.97). Cigarette smoking was associated with a higher risk (OR, 1.97; 95% CI, 1.02-3.81 for > 20 pack-years vs. never), whereas an inverse association was seen for use of aspirin and other nonsteroidal anti-inflammatory drugs (OR, 0.29; 95% CI, 0.12-0.67 for once per day or more vs. never). CONCLUSIONS: Hyperplastic polyps share common lifestyle risk factors with colorectal adenomas and carcinomas. 相似文献
65.
Eleven optical brighteners have been qualitatively and quantitatively determined using C18, C8, or C2 reverse phase high performance liquid chromatography (HPLC) columns. Comparable results also were obtained using radially
compressed reverse phase HPLC cartridges. Mobile phases consist of acetonitrile and methanol in water with 0.05 M phosphate
buffer. Quaternary ammonium salts also are added to the mobile phase for ion pair formation. Ultraviolet (UV) detection at
340 nm gives more than adequate sensitivity for brighteners formulated between 0.05 and 2.0%. Sample preparation is simple
and all components can be eluted within 15 min. Powdered and liquid detergents, fabric softeners, and bleach boosters have
been routinely analyzed and results closely agree with those obtained using thin layer chromatography and densitometry. 相似文献
66.
JV Lloyd AM Street E Berry J McPherson H Ekert A Lammi WR McWhirter EM Duncan EL Maxwell J Rowell RI Baker MF Leahy D Jupe 《Canadian Metallurgical Quarterly》1997,27(6):658-664
BACKGROUND: Inhibitory antibodies which neutralise factor VIII develop in 10-20% of individuals with inherited haemophilia A and rarely as autoantibodies in normal individuals to cause acquired haemophilia. The antibodies are directed against human factor VIII but cross-react to varying degrees with porcine factor VIII. Porcine factor VIII can be used for treatment in individuals with low cross-reactivity. AIMS: To determine the cross-reactivity of factor VIII inhibitors between human factor VIII and porcine factor VIII, in a population of patients with inherited and acquired haemophilia A. Also, to determine whether patients with inherited haemophilia and inhibitors have a higher incidence of factor VIII gene inversion in intron 22. METHODS: Samples and data sheets from 43 patients with inherited and ten with acquired haemophilia were submitted from hospitals in Australia and New Zealand. Inhibitor levels to human and porcine factor VIII were measured by the Bethesda method in 39 with inherited and nine with acquired haemophilia A. RESULTS: Of 39 patients with inherited haemophilia A, cross-reactivity was 0% in 17 patients, 1-19% in six, 20-39% in 11 and 40-80% in five. In six of nine patients with acquired haemophilia cross-reactivity was < or = 7%. In inherited severe haemophilia A, the frequency of the intron 22 inversion was not greater in 37 study patients than in 28 patients without an inhibitor. CONCLUSIONS: Many patients in Australia and New Zealand with inhibitors to human factor VIII presently show a low or absent level of cross-reactivity to porcine factor VIII. These may respond to treatment with this concentrate at least in the short term. There remains a group of patients with high cross-reactivity who will respond only to recombinant factor VIIa or prothrombin complex concentrates. 相似文献
67.
In a prospective study of the value of gallium-67 scintigraphy in cases of multisystem malignant melanoma, 69 scans were obtained for 36 patients. No abnormality was found in 18 scans; in only 3 was there other evidence of disease. Of 54 sites of disease demonstrated by scintigraphy, 40 were correlated with other investigations: biopsy (5), surgery (7), autopsy (7), radiographic (13), or clinical (8). Metastatic melanoma was found in 37 (69%) of the sites; no such disease was found in 3 (5.7%). The life expectancy of patients with an abnormal scan was shorter than that of patients with a normal scan. Gallium studies reliably indicated the extent of multisystem melanoma, and are of value in clinical management. 相似文献
68.
69.
T. Zheng J. Zhan J. Pang G.S. Tan J. He G.L. McPherson Y. Lu V.T. John 《Advanced materials (Deerfield Beach, Fla.)》2006,18(20):2735-2738
70.
R. McPherson N. Gane T. J. Bastow 《Journal of materials science. Materials in medicine》1995,6(6):327-334
Plasma-sprayed hydroxylapatite coatings, widely used on metallic surgical implants to improve their adhesion to bone, are formed by rapid quenching of molten, or partly molten, particles which impact the substrate at high velocity. the performance of these coatings in the body depends upon their structure, which is not well understood. Coatings prepared under a range of spraying conditions have been studied by X-ray diffraction (XRD). differential thermal analysis (DTA), thermogravimetric analysis (TGA) and solid-state nuclear magnetic resonance spectroscopy (NMR). The results suggest that particles partly melt and lose combined water at lower plasma torch input powers forming a glass, by quenching of the liquid phase, and an OH-depleted hydroxylapatite residual crystalline phase. At higher power inputs an increasing amount of P2O5 is also lost and the coatings contain CaO and Ca4P2O9. Heat treatment of coatings in air at 600°C results in crystallization of the glass phase and reaction with water vapour to form hydroxylapatite. The results show that XRD is relatively insensitive to some of the structural details of hydroxylapatite coatings which may be significant to their performance. NMR provides more structural information and is a significant tool for coating characterization.Sadly Professor McPherson died after completing this paper. He made a distinctive contribution to the fields of ceramics and thermal spraying and will be missed by the international community. 相似文献