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991.
992.
CL Smith 《Canadian Metallurgical Quarterly》1998,7(6):703-709
OBJECTIVE: To provide national-level data concerning the percentage of pharmacies selling tobacco products, examine relationships between selling practices and pharmacy characteristic variables, and explore perceptions of conflicts between tobacco-selling activity and professional and personal values and the potential effects of such conflicts. DESIGN, SETTING, PARTICIPANTS: Data were collected from a geographically stratified systematic random sample of 899 pharmacies. Multiple mailings were sent to the attention of the pharmacy manager. A random sample of nonrespondents was also contacted by telephone, urging participation. MAIN OUTCOME MEASURES: Whether the pharmacy currently sold cigarettes and/or smokeless tobacco products, and if so, whether these practices differed from what respondents' personal or professional values tell them to do. Scales designed to measure job satisfaction, job-induced tension, and propensity to leave were also included. RESULTS: Slightly more than half (50.5%) of the pharmacies sold cigarettes and 35.4% sold smokeless tobacco products. Independents were less likely than chain pharmacies to sell tobacco products. For those respondents working in pharmacies where tobacco products were sold, 47.6% responded that this practice differs from what their personal values tell them to do and 63.9% replied that this practice differs from what their professional values tell them to do. Even when controlling for pharmacy type, respondents working in pharmacies that sold tobacco products had significantly lower levels of global job satisfaction, higher levels of job-induced tension, and a higher propensity to leave than did respondents working in pharmacies that did not. CONCLUSION: Decision makers in pharmacies where tobacco products are still sold should take a serious look at the justification for the continued availability of tobacco products in an environment that has a goal of promoting health. 相似文献
993.
E Kessopoulou HJ Powers KK Sharma MJ Pearson JM Russell ID Cooke CL Barratt 《Canadian Metallurgical Quarterly》1995,64(4):825-831
OBJECTIVE: To determine the effectiveness of the in vivo administration of vitamin E as treatment for reactive oxygen species-associated male infertility. SETTING: University-based center for reproductive medicine. DESIGN: Double-blind randomized placebo cross-over controlled trial. PATIENTS, PARTICIPANTS: Thirty healthy men with high levels of reactive oxygen species generation in semen and a normal female partner. INTERVENTIONS: Patients were allocated to two groups according to the blinded randomization. Each patient received either 600 mg/d of vitamin E (Ephynal, 300 mg tablets; F. Hoffman-La Roche Ltd., Basle, Switzerland) (order A) or identical placebo tablets (order B) for 3 months. Then after a 1-month wash-out period the patients were crossed-over to the other treatment. MAIN OUTCOME MEASURES: Improvement in the in vitro function of the spermatozoa measured by conventional semen analysis, computerized motility assessment, determination of reactive oxygen species generation, binding to the zona pellucida of the unfertilized human oocyte in a competitive zona binding assay, development of hyperactivated motility (both spontaneous and in the presence of 20% of the natural agonist, human follicular fluid) and pregnancy. RESULTS: Rise in the blood serum vitamin E levels after treatment accompanied by improvement in one of the sperm function tests: the zona binding assay. The zona binding ratio for order A improved from 0.2 (range 0 to 0.5) before treatment to 0.5 (range 0.1 to 1.0) after treatment, the corresponding values for order B were 0.2 (range 0 to 1.0) before treatment and 0.3 (range 0.1 to 0.7) after treatment. CONCLUSION: Oral administration of vitamin E significantly improves the in vitro function of human spermatozoa as assessed by the zona binding test. 相似文献
994.
Z Chen S Izenwasser JL Katz N Zhu CL Klein ML Trudell 《Canadian Metallurgical Quarterly》1996,39(24):4744-4749
A series of 9-methyl-3 beta-phenyl-2-substituted-9-azabicyclo[3.3.1]nonane derivatives were synthesized and evaluated as cocaine-binding site ligands at the dopamine transporter (DAT). The conformation of the bicyclic structures and the stereochemistry of the substituents were determined by NMR and X-ray crystallography. The in vitro binding affinity (Ki) of the 9-azabicyclo[3.3.1]nonane derivatives was measured in rat caudate-putamen tissue, and they were found to be 100-fold (Ki = 2-14 microM) less potent than cocaine and other tropane analogs. From these results it is evident that the cocaine-binding site at the DAT is very sensitive to structural modifications of the unsubstituted methylene bridge [C(6)-C(7)] of cocaine and cocaine-like compounds. 相似文献
995.
The objective of this prospective, cohort study was to compare the nutritional status of full-term infants who were fed human milk (BF, n = 29), formula (FF, n = 30) or evaporated milk formulae (EM, n = 30) for at least 3 months. Infants were seen at enrollment, 3 and 6 months, at which times a blood sample, diet record and anthropometric data were collected. Infants in the EM group received solids earlier (12 +/- 5 weeks) than did FF infants (15 +/- 4 weeks), and both were earlier than BF infants (19 +/- 4 weeks). Only 26% of the EM fed group received iron supplements as ferrous sulphate drops. Seven BF, 12 FF and 20 EM had abnormal ferritin values (< 10 ng ml-1) at 6 months. Copper intake was lower in the EM infants at 3 and 6 months. However, plasma copper and erythrocyte copper zinc superoxide dismutase (ZnCuSOD) levels did not differ between groups. Selenium intake was lower in the EM group (5 +/- 1 and 10 +/- 5 micrograms d-1; 3 and 6 months) than in the FF infants (13 +/- 4 and 19 +/- 7 micrograms d-1; 3 and 6 months). Erythrocyte SeGHSPx levels in EM infants were lower at 6 months (EM, 33.2 +/- 3.4; FF. 35.2 +/- 3.9: BF, 36.1 +/- 3.8 mU mg Hb-1). Thiamin intake (0.99 +/- 0.08 and 1.24 +/- 0.32; 3 and 6 months, mg 1000 kcal-1) was higher in the FF group than in EM infants (0.38 +/- 0.39 and 0.66 +/- 0.38; 3 and 6 months). There were more (13%) abnormal thiamin assays in the EM group at 6 months than in the BF and FF infants (0%). In conclusion, infants fed evaporated milk formula receive adequate copper but may not receive enough thiamin or selenium. Unless supplemented from birth with medicinal iron, intakes of iron will be inadequate. 相似文献
996.
997.
998.
JC Alsup CL Greenfield LL Hungerford BC McKiernan HE Whiteley 《Canadian Metallurgical Quarterly》1997,38(5):287-293
This study evaluated changes in respiratory function in dogs with experimentally induced laryngeal paralysis treated with either unilateral arytenoid lateralization or ventral ventriculocordectomy, and compared the effectiveness of these procedures. Evaluation consisted of clinical assessment and tidal breathing flow volume loop and upper airway resistance measurements. Carbon dioxide and doxapram hydrochloride were used as respiratory stimulants. Initially, all dogs improved clinically after corrective surgery. However, by the end of the study, laryngeal collapse had developed in 2 of 5 dogs corrected by ventral ventriculocordectomy. No statistical differences in upper airway mechanics testing were seen between the surgical procedures. With both groups combined, many measurements of upper airway obstruction improved after surgical correction. Based on this study, these surgical procedures yield comparable results, although additional studies are needed to evaluate both the cause of laryngeal collapse and the role of upper airway mechanics testing in the evaluation of canine laryngeal paralysis. 相似文献
999.
CL Harmer 《Canadian Metallurgical Quarterly》1996,25(3):413-419
Surgery is the definitive and potentially curative treatment for the slow growing well-differentiated papillary and follicular carcinomas. Total (or near-total) thyroidectomy is required, together with excision of adjacent lymph nodes when involved, or a modified block dissection if there is extensive lymphatic involvement. Ablation of residual normal thyroid with radioactive iodine usually follows as this will permit subsequent whole-body I-131 scanning to exclude the presence of residual or metastatic disease. Normally such patients have an excellent prognosis and can be followed simply with serum thyroglobulin estimations. Occasionally therapeutic radioactive iodine is necessary to eradicate metastatic disease. The anaplastic carcinomas grow and metastasise with explosive rapidity. They are typically inoperable at presentation and have no ability to concentrate iodine. Prognosis is appalling with external beam radiotherapy providing only palliation. Medullary carcinoma is different again as it arises from the parafollicular or C-cells. Total thyroidectomy must be undertaken as these tumours may be multifocal; a central compartment neck resection is ideally undertaken at the same time, together with a formal block dissection if lymph node disease is found to be present. External beam radiotherapy is often required. These tumours can be inherited and produce the tumour marker calcitonin. The rarest group of thyroid cancer is the lymphomas. Like the anaplastic carcinomas, they grow very rapidly but, unlike the former, are radio-responsive. The additional use of chemotherapy is necessary when they are of advanced stage or demonstrate poor prognostic factors. 相似文献
1000.