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51.
DG Wang WH Liu FT Lundy KM Pogue RT Cunningham CF Johnston KD Buchanan 《Canadian Metallurgical Quarterly》1998,184(4):408-413
This epidemiological study investigated the reasons why children in Northern Ireland who need orthodontic treatment do not receive treatment even when it is provided free by the state. A total of 1584 15- and 16-year-olds were examined in 23 high schools with the Index of Orthodontic Treatment Need. The characteristics of the adolescents who had received orthodontic treatment were compared with those who had a definite need for treatment and yet did not receive treatment or advice. One in 10 of the adolescents examined had an unmet need for orthodontic treatment. Logistic regression analysis was used to assess the influence of 11 variables including socioeconomic status, religion, and standard of dental health on the uptake of orthodontic care. This analysis revealed that the only significant predictors of whether an adolescent received orthodontic treatment was the dental attendance pattern of the adolescent, the adolescent's dental health, and the dental attendance pattern of the adolescent's mother. Those adolescents who had good dental health, who regularly attended a dentist, and whose mother regularly attended a dentist were more likely to receive orthodontic treatment. 相似文献
52.
L Rodríguez FP Chávez ME González L Basabe T Rivero 《Canadian Metallurgical Quarterly》1998,14(15):1399-1406
The URA3 gene of Candida utilis encoding orotidine-5'-phosphate decarboxylase enzyme was isolated by complementation in Escherichia coli pyrF mutation. The deduced amino-acid sequence is highly similar to that of the Ura3 proteins from other yeast and fungal species. An extensive analysis of the family of orotidine-5'-phosphate decarboxylase is shown. The URA3 gene of C. utilis was able to complement functionally the ura3 mutation of Saccharomyces cerevisiae. 相似文献
53.
The adult gypsy moth, Lymantria dispar (Lymantriidae: Noctuoidea) has a pair of metathoracic tympanic ears that each contain a two-celled auditory chordotonal organ (CO). The earless forest tent caterpillar moth, Malacosoma disstria (Lasiocampidae: Bombycoidea), has a homologous pair of three-celled, nonauditory hindwing COs in their place. The purpose of our study was to determine whether the adult CO in both species arises from a preexisting larval organ or if it develops as a novel structure during metamorphosis. We describe the larval metathoracic nervous system of L. dispar and M. disstria, and identify a three-celled chordotonal organ in the anatomically homologous site as the adult CO. If the larval CO is severed from the homologue of the adult auditory nerve (IIIN1b1) in L. dispar prior to metamorphosis, the adult develops an ear lacking an auditory organ. Axonal backfills of the larval IIIN1b1 nerve in both species reveal three chordotonal sensory neurons and one nonchordotonal multipolar cell. The axons of these cells project into tracts of the central nervous system putatively homologous with those of the auditory pathway in adult L. dispar. Following metamorphosis, M. disstria moths retain all four cells (three CO and one multipolar) while L. dispar adults possess two cells that service the auditory CO and one nonauditory, multipolar cell. We conclude that the larval IIIN1b1 CO is the precursor of both the auditory organ in L. dispar and the putative proprioceptor CO in M. disstria and represents the premetamorphic condition of these insects. The implications of our results in understanding the evolution of the ear in the Lepidoptera and insects in general are discussed. 相似文献
54.
FP Meyer 《Canadian Metallurgical Quarterly》1998,5(6):266-271
About the 'Omnipotence' of the Chelation Therapy In the eighties the 'method of treatment proven in many thousands of cases over 20 years' was transferred from the USA to Germany (enjoys a priori considerable faith) using very dubious promises. It was Clarke et al. who introduced this 'therapy' in 1955. The dubious promise was to maintain that the chelation therapy eliminates or alleviates symptoms in the case of the following illnesses: Alzheimer's disease, senility, schizophrenia, rheumatoid arthritis, osteoarthritis, gout, renal calculus, apoplectic coma, gallstones, multiple sclerosis, osteoporosis, chronic fatigue syndrome, varicose veins, hypertension, failure of memory, scleroderma, Raynaud's disease, digitalis intoxication, intermittent claudication, diabetic ulcer, disturbance of the blood supply, ulcer on the legs, snake poison, impotence, emotional difficulties, defective hearing, vision disorder. There is not the slightest proof of effectiveness for any of the listed indications. The burden of proof lies with the supplier. Even in the case of the relatively often examined peripheral atherosclerotic changes (claudicatio intermittens) there is no proof that EDTA has a greater effect than placebo. For coronary heart disease too there is no evidence for any usefulness of the chelation therapy beyond that of a placebo effect. Only controlled studies can help to improve the therapy in the sense of 'Evidence-based medicine'. Retrospective investigations on thousands of patients cannot 'prove' anything, although this is maintained again andagain. 相似文献
55.
B Benari H Kiat J Erel M Hyun FP Wang C Williams JD Friedman G Germano KF Van Train D Berman 《Canadian Metallurgical Quarterly》1995,2(6):478-484
Bacterial antibodies were studied in acute, intermediate and convalescent phase sera (mean duration from first to last sample 36 days) of 121 children hospitalized for acute lower respiratory tract infection. Antibody responses were observed in 45% of all cases and in 29% of the 21 children < 1 year old. A total of 15 responses to Streptococcus pneumoniae (pneumolysin), 20 to Haemophilus influenzae, 9 to Moraxella catarrhalis, 3 to chlamydiae and 8 to Mycoplasma pneumoniae were found. In 79 patients with 4 consecutive samples available, 52% of the 31 responses were measurable within 5 days from admission. Overall the responses were not associated with upper respiratory tract bacterial findings or acute otitis media. Significantly more responses were found in the 121 children with acute lower respiratory tract infection than in healthy controls (P < 0.007). We conclude that bacterial antibody assays provide a useful tool in the study of the etiology of acute lower respiratory tract infection in young children, even if the interval between paired serum samples is short. 相似文献
56.
KE Anderson GJ Hammons FF Kadlubar JD Potter KR Kaderlik KF Ilett RF Minchin CH Teitel HC Chou MV Martin FP Guengerich GW Barone NP Lang LA Peterson 《Canadian Metallurgical Quarterly》1997,18(5):1085-1092
Epidemiologic studies have suggested that aromatic amines (and nitroaromatic hydrocarbons) may be carcinogenic for human pancreas. Pancreatic tissues from 29 organ donors (13 smokers, 16 non-smokers) were examined for their ability to metabolize aromatic amines and other carcinogens. Microsomes showed no activity for cytochrome P450 (P450) 1A2-dependent N-oxidation of 4-aminobiphenyl (ABP) or for the following activities (and associated P450s): aminopyrine N-demethylation and ethylmorphine N-demethylation (P450 3A4); ethoxyresorufin O-deethylation (P450 1A1) and pentoxyresorufin O-dealkylation (P450 2B6); p-nitrophenol hydroxylation and N-nitrosodimethyl-amine N-demethylation (P450 2E1); lauric acid omega-hydroxylation (P450 4A1); and 4-(methylnitrosamino)-1-(3-pyridyl-1-butanol) (NNAL) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) alpha-oxidation (P450 1A2, 2A6, 2D6). Antibodies were used to examine microsomal levels of P450 1A2, 2A6, 2C8/9/18/19, 2E1, 2D6, and 3A3/4/5/7 and epoxide hydrolase. Immunoblots detected only epoxide hydrolase at low levels; P450 levels were <1% of liver. Microsomal benzidine/prostaglandin hydroperoxidation activity was low. In pancreatic cytosols and microsomes, 4-nitrobiphenyl reductase activities were present at levels comparable to human liver. The O-acetyltransferase activity (AcCoA-dependent DNA-binding of [3H]N-hydroxy-ABP) of pancreatic cytosols was high, about twothirds the levels measured in human colon. Cytosols showed high activity for N-acetylation of p-aminobenzoic acid, but not of sulfamethazine, indicating that acetyltransferase-1 (NAT1) is predominantly expressed in this tissue. Cytosolic sulfotransferase was detected at low levels. Using 32P-post-labeling enhanced by butanol extraction, putative arylamine-DNA adducts were detected in most samples. Moreover, in eight of 29 DNA samples, a major adduct was observed that was chromatographically identical to the predominant ABP-DNA adduct, N-(deoxyguanosin-8-yl)-ABP. These results are consistent with a hypothesis that aromatic amines and nitroaromatic hydrocarbons may be involved in the etiology of human pancreatic cancer. 相似文献
57.
CN Mock RV Maier E Boyle S Pilcher FP Rivara 《Canadian Metallurgical Quarterly》1995,39(1):29-33; discussion 34-5
Head injuries (HIs) remain a major contributor to trauma mortality, with many deaths occurring despite optimal use of available therapy. Injury prevention is vital to decrease the impact of HIs. Helmets can decrease the severity of HIs in both bicycle crashes (BCs) and motorcycle crashes (MCCs). A major challenge is to increase helmet use. A mandatory motorcycle helmet law in 1990 and information campaigns aimed at bicyclists have increased the percentage of riders wearing helmets in Washington State. We hypothesized that there would be an associated decrease in the proportion of severe HIs in BC and MCC admissions to the state's only level I trauma center. We analyzed injury region and outcomes for all 466 BC and 992 MCC instate admissions from 1986 to 1993. For BCs, the proportion of severe HIs (Abbreviated Injury Scale score of 4 or 5) declined from 29% in 1986 to 11% in 1993 (p = 0.02). BC trends paralleled helmet use in observations on 8,860 bicycle riders in the area, in which the percentage of helmeted riders rose from 5% in 1987 to 62% in 1993 (p < 0.001). For MCCs, severe HIs declined from 20% before passage of the helmet law to 9% afterward (p < 0.001). Mortality decreased for BCs and MCCs (p < 0.05), and length of hospital stay and ICU stay decreased for BCs (p < 0.05). The percentage of helmeted BC admissions rose from 0% to 32% (p = 0.009), and helmeted MCC admissions rose from 41% to 80% (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
58.
E de Bri W Lei FP Reinholt S Mengarelli-Widholm D Heing?rd O Svensson 《Canadian Metallurgical Quarterly》1997,5(6):387-393
OBJECTIVE: To compare the efficacy and tolerability of mibefradil and amlodipine in patients with uncomplicated mild-to-moderate essential hypertension. DESIGN: A double-blind, randomised, parallel group multicentre trial. METHODS: 239 patients received 50 mg mibefradil or 5 mg amlodipine for 4 weeks, followed by a forced titration to 100 mg mibefradil or 10 mg amlodipine for an additional 8 weeks. Patients then entered a 4-week withdrawal period either on therapy or switched to placebo. RESULTS: Statistically equivalent reductions in trough sitting diastolic blood pressure (SDBP) were observed after 12 weeks of once-daily treatment with 50/100 mg mibefradil (-11.5 +/- 8.2 mm Hg) and 5/10 mg amlodipine (-13.2 +/- 7.9 mm Hg). The number of patients with normalised SDBP (< or = 90 mm Hg) increased 23.3% in the mibefradil group and 19.5% in the amlodipine group (approximately 74% in both groups). Patients on mibefradil or amlodipine during the withdrawal period had significantly larger decreases in SDBP than those on placebo. Patients on mibefradil had a decrease in heart rate of 5.5 bpm. Patients on amlodipine had no change in heart rate; however, cessation of amlodipine was associated with a decrease in heart rate. CONCLUSIONS: Mibefradil was as effective as amlodipine in reducing BP; both compounds were effective treatments of hypertension. 相似文献
59.
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