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961.
    
Summary Trends in age-specific and age-standardized death certification rates from motor vehicle accidents over the period 1950–1990 were analyzed for 48 countries from four continents (2 from North America, 10 from Latin America, 8 from Asia, 26 from Europe, Australia and New Zealand) on the basis of data produced by the World Health Organization mortality database. In most developed western and Asiatic countries, mortality rates increased until the late 1960's or early 1970's, and declined thereafter to reach values often lower than those of the early 1950's, although the number of circulating vehicles has substantially increased over the same calendar period. The extent of the decline was, however, different in various countries, as well as in the two sexes and in various age groups, thus leading to complex cohort and period patterns. In general, countries (like the U. S. A. or U. K.), where the number of motor vehicles had increased earlier, have now comparatively higher rates at younger than at middle and older age, while the opposite is observed in countries with later spread of motor vehicles. Further, there were a few countries, including Kuwait, Venezuela and several other Latin American countries, Australia and New Zealand, and several southern and eastern European countries, with exceedingly high rates from motor vehicle accidents, and where comprehensive interventions on this important cause of death are therefore a public health priority.  相似文献   
962.
963.
964.
Summary The element content of ossified auricles in two patients with Addison's disease was determined by X-ray microanalysis. The results showed a similar element content of the ossified auricles of the Addison's patients and control bone specimens. The calcium and phosphorus content of the petrified auricles was, however, slightly decreased compared with the iliac bone biopsies of the patients. The sulfur content of the ossified auricles was higher than that of their bones, but markedly lower than control auricular cartilage. Iron, sodium, and chloride contents were similar in the ossified auricles and in the normal auricular cartilage, whereas only trace amounts of these elements were detected in the bone. The auricles of the patients with Addison's disease possessed relatively high aluminium content compared with both control bone and cartilage. The element content of the bone biopsies from Addison patients was comparable to control bone. The presence of trace amounts of aluminium in the petrified auricles of Addison's patients is probably attributed to a long period of aluminium hydroxide consumption.  相似文献   
965.
Summary Twenty patients with advanced squamous cell carcinomas (SCC) of the head and neck were entered into a phase II study of mitoxantrone at a dosage of either 12 mg/m2 or 14 mg/m2 given at 3 weekly intervals. None of the patients had received prior chemotherapy. One patient had a partial remission. Two patients died from unrelated causes. One patient withdrew from the trial prior to receiving any chemotherapy. Sixteen patients either failed to respond or progressed during the course of the treatment. Side effects included nausea and vomiting in 6 patients and neutropenia in 6 patients. This study failed to detect a significant response of squamous cell carcinomas of the head and neck to mitoxantrone therapy at the described doses.  相似文献   
966.
Etiology of childhood deafness with reference to the group of unknown cause   总被引:1,自引:0,他引:1  
A systematic follow-up of children diagnosed as deaf may reveal additional pertinent information which may be instrumental in ascertaining the cause of deafness. 107 deaf children were detected by a prospective study of 62 000 children screened for deafness during 11 years. The cause of deafness could be determined in 63 children while in 44 no etiology was apparent. Investigation of the 44 children revealed a genetic origin of deafness in 12 additional children. Consanguinity was evident in the children whose deafness was of genetic origin. Identification of the cause of deafness in children contributes to prevention of this handicap.  相似文献   
967.
968.
1. Both the cytochrome P-450-dependent mono-oxygenase system and the FAD-containing mono-oxygenase catalyse the sulphoxidation of thioether-containing organophosphate insecticides. Using purified FAD-containing mono-oxygenase and purified cytochrome P-450 isozymes isolated from mouse liver microsomes, the stereospecificity of the oxidation of phorate to (+)-and (-)-phorate sulphoxide and the further oxidations of the (+)-and (-)-phorate sulphoxides to the sulphone, the oxon sulphoxide and the oxon sulphone were examined. 2. The FAD-containing mono-oxygenase catalysed the formation of (-)-phorate sulphoxide, while two cytochrome P-450 isozymes (cytochrome P-450-B2, a constitutive form, and cytochrome P-450-PB, the principal form induced by phenobarbital) produced (+)-phorate sulphoxide. The other three constitutive cytochrome P-450 isozymes examined yielded racemic mixtures. 3. The FAD-containing mono-oxygenase had the lowest Km for the sulphoxidation reaction, 32 microM, while the Km values for the cytochrome P-450 isozymes ranged from 67 microM to 250 microM. No additional oxidation of phorate sulphoxide by the FAD-containing monooxygenase was detected using either (+)-phorate sulphoxide or (-)-phorate sulphoxide as substrates. 4. In contrast, all five cytochrome P-450 isozymes tested formed additional oxidation products; the (+)-phorate sulphoxide was the preferred substrate for all cytochrome P-450 forms. 5. The final oxidation product, phorate oxon sulphone, was derived by desulphuration of phorate sulphone, with the formation of the oxon sulphoxide being a terminal pathway.  相似文献   
969.
Vasography may cause stricture of the vas deferens. The probable causes of this obstruction are traumatic lesion at the puncture site and the radiological contrast material used. Because of this problem we performed an experimental study using Wistar rats, which were divided into four groups: Group A—Control, Group B—injection of a saline solution, Group C—hypaque injection, Group D—hypaque plus saline solution. According to the results obtained it was concluded that the needle puncture is not responsible for stricture of the vas deferens. Hypaque is responsible for 5% of strictures and the use of a saline solution to wash the vas did not show any benefit. This work was supported in part by Conselho Nacional de Desenvolvimento Cientifico e Tecnológico (CNPQ).  相似文献   
970.
Although most authors do not recommend prenatal puncture of a unilateral single cystic renal mass, in case the contralateral kidney is normal and there is sufficient amniotic fluid, this case report shows that the procedure, which can be done very carefully under ultrasonic guidance, can be helpful in establishing the presumed diagnosis.  相似文献   
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