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1.
Numerous surveys at the national and regional level have demonstrated that large inequalities in infant health status exist in Southern Africa. Few studies have assessed infant mortality at the intra-urban scale of geographic analysis. Comparisons between infant mortality rates from different areas are made even more meaningful if the data are divided into two primary categories based on period-of-death; these being the neonatal and post-neonatal components. This study presents the results of a survey undertaken in Metropolitan Cape Town (population 1.6 million) during 1982. The aim was to determine the spatial variation of neonatal and post-neonatal mortality at the suburb (or community) level within the city. Overall, a total of 36,789 live births and 928 infant deaths were recorded; 53.4% in the neonatal period and 46.6% in the post-neonatal period. The mean infant mortality rate was 25.2 per 1000 live births; the neonatal mortality rate and post-neonatal mortality rate being 13.5/1000 and 11.7/1000, respectively. A marked range in death rates was evident for both components. For the neonatal category it was 0.0-49.9/1000 and 0.0-40.0/1000 for the post-neonatal period. The generally low post-neonatal mortality rate among the 69 suburbs studied has made the neonatal component the dominant contributor to the infant mortality rate. However, in the lowest socio-economic areas the post-neonatal mortality rate was responsible for over 60% of infant deaths.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Osteoporosis is a common disease with a strong genetic component characterized by reduced bone mass and an increased risk of fragility fractures. Bone mineral density (BMD) is the most important determinant of osteoporotic fracture risk, but the genes responsible for BMD regulation and fracture are incompletely defined. To enable multi-center studies to examine the genetic influences on BMD there is a requirement to standardize measurements across different manufacturers of bone densitometers, different versions of machines and different normative ranges. This paper describes a method developed to allow near-identical subjects with low age-adjusted BMD (based on Z-scores) to be recruited in 17 centers using 27 different densitometers. Cross-calibration was based on measurements using a European spine phantom circulated to all centers and measured ten times on each individual machine. From theses values an individual exponential curve, based on nominal versus observed BMD, was derived for each machine. As expected, there were large and significant variations in nominal BMD values, not only between scanners from different manufacturers but also between different versions of scanners from the same manufacturer. Hologic scanners tended to underestimate the nominal BMD, while Lunar scanners overestimated the value. Norland scanners gave mixed values over estimating BMD at the lower nominal value (0.5 g/cm2) while underestimating the value at the higher value (1.5 g/cm2). The validity of the exponential equations was tested using hip and spine measurements on 991 non-proband women from a familial osteoporosis study (FAMOS). After cross-calibration there was a considerable reduction in variation between machines. This observation, coupled with the absence of a similar reduction in variation attributable to a linear regression on age, demonstrated the validity of the cross-calibration approach. Use of the cross-calibration curves along with a standard normative range (in the case of this study, the Hologic normative range) allowed age-specific Z-scores to be used as an inclusion criterion in this genetic study, a method that will be useful for other trials where age-specific BMD inclusion criteria are required.  相似文献   
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Say yes to life: a pilot study.   总被引:1,自引:1,他引:0       下载免费PDF全文
In an attempt to assess whether there are any characteristics which a majority of ordinary people regard as life-affirming or life-denying, a questionnaire was given to a pilot group of 167 respondents, representing three different age and social categories. Five life-affirming and five life-denying characteristics were mentioned by more than 10% of respondents. Of the former, Drive, Sociability, Happiness and Optimism were endorsed by 15-20%. Of the latter, Unsociability and Poor Coping were mentioned by 22%, making them distinctly more frequent than the following categories of Pessimism, Lack of Drive and Unhappiness (11-14%). It is suggested that a number of these subjectively determined characteristics, which the general public perceive as being life-affirming or denying, do indeed influence physical or mental health, illness or illness behaviour. It may therefore be of value to utilize this set of public perceptions in future programmes of health education.  相似文献   
5.
The antiviral nucleoside derivative zidovudine (3'-azido-3'-deoxythymidine) previously has been shown to be an effective antibacterial agent in animals infected with Escherichia coli or Salmonella typhimurium. Since HIV infection can alter the course of human syphilis with serious consequences, it was of interest to determine if the noncultivable spirochaetal agent of syphilis, Treponema pallidum, is susceptible to this compound. The progression of experimental rabbit syphilis over a three week period was unchanged in animals receiving either 50 or 150 mg/kg oral zidovudine daily. In addition, a number of cultivable pathogenic and nonpathogenic spirochaetes were tested for susceptibility to zidovudine in vitro. At a concentration of 100 mg/L, zidovudine had no detectable effect on spirochaete growth, morphology, or motility. Thus it appears that spirochaetes are generally not susceptible to this compound, and that long-term zidovudine therapy will not be of benefit in preventing or controlling syphilis or other spirochaetoses in HIV-infected humans receiving this drug.  相似文献   
6.
The effect of valproic acid on the distribution of gavaged 65Zn in maternal and embryonic tissue of Sprague-Dawley rats was examined 24 h after gavaging of the drug on d 13 of pregnancy. Valproic acid treatment resulted in a significantly higher retention of 65Zn in maternal liver and lower amounts in uterus, placenta and embryos than in controls. Compared to controls, gel chromatography of maternal liver from valproic acid-treated dams showed higher 65Zn counts associated with a protein peak of molecular weight of 6,500, the approximate molecular weight of the Zn-binding protein metallothionein. These results support the idea that the teratogenicity of valproic acid is in part due to an induction of embryonic Zn deficiency secondary to a drug-induced sequestering of Zn into maternal liver that results in a decrease in maternal plasma Zn and subsequent reduction in embryonic Zn uptake.  相似文献   
7.
This study examined the axonal transport of substance P-like immunoreactivity (SPLI) and its content in dorsal root ganglion, trigeminal ganglion, stomach and ileum of non-diabetic rats and two groups of rats with streptozotocin-induced diabetes of 9 months duration. One diabetic group received the aldose reductase inhibitor ‘Statil’ throughout the period of study. To reduce morbidity all diabetic animals were given twice-weekly injections of a long-acting insulin which restricted weight loss but did not prevent regular and severe hyperglycaemia. Axonal transport of SPLI was studied by measurement of accumulation at 12 h ligatures on the left sciatic nerve. There were no differences between the 3 groups either in the calculated anterograde and retrograde mean rates of accumulation (ranges 6.0 to 7.6 and 0.38 to 0.72 mm/h respectively) or mobile fractions of SPLI (means from 0.54 to 0.58). There were, however, marked reductions in anterograde and retrograde accumulations of SPLI in the constricted nerves of the ‘untreated’ diabetics (respectively 57 and 33% of controls;P < 0.01 for both). In the ‘Statil’-treated rats these deficits were attenuated (80 and 75% of controls). Diabetes also reduced the SPLI content of unligated sciatic nerve and trigeminal ganglion (65 and 75% of controls). ‘Statil’ prevented the deficit in the ganglion, but not in the nerve. ‘Statil’ treatment prevented themyo-inositol depletion and attenuated the sorbitol and fructose accumulation seen in the sciatic nerves of the untreated diabetic animals suggesting effective inhibition of aldose reductase in this tissue. The total SPLI content of the stomach and 1-cm segments of ileum were unaltered in the diabetic animals but due to the increased weights of these tissues the SPLI content per unit weight was reduced. These changes were unaffected by ‘Statil’.  相似文献   
8.
We have investigated an extended pedigree with three cousins affected by Duchenne muscular dystrophy with apparent transmission through the male line. However, molecular studies have shown that one boy has a de novo duplication, another has a deletion, and the molecular mutation has yet to be defined in the third boy. All three X chromosomes in the affected boys appear to have a different origin. We speculate on the mechanisms by which the Duchenne locus may be particularly prone to mutation in this family and the possible involvement of transposons is discussed. Whatever the mechanism involved, the occurrence of three different mutations in one pedigree is a rare event.  相似文献   
9.
Ethnic minorities in British diabetic clinics: a questionnaire survey   总被引:1,自引:0,他引:1  
A questionnaire was sent by the British Diabetic Association to hospital consultant physicians caring for diabetic patients in the UK to estimate the number of ethnic minority patients attending British Diabetic clinics, and the availability of special facilities for their care. Sixty-two clinics were estimated to have at least 50 Asian patients, and 25 had at least 200 Asian patients. For Afro-Caribbeans the corresponding figures were 33 and 14 clinics, respectively. Clinics serving a relatively high proportion of these patient groups were situated primarily in Greater London, the Midlands and the North West. Approximately 40% of clinics with over 50 Asians had no specifically adapted diet sheets, and 34% had no hospital interpreter service. Tapes, slides or video presentations were available in only eight clinics. There is an urgent need to improve the provision of special facilities to clinics with substantial numbers of ethnic minority patients.  相似文献   
10.
Some patients present with distressing symptoms due to locally advanced prostatic carcinoma which may be refractory to hormonal manipulation and/or surgical treatment. Over an 8-year period 26 patients received local palliative radiotherapy for recurrent bleeding and lower urinary outflow tract obstruction. All were treated with conventional external beam radiotherapy and all but 2 obtained useful palliation of symptoms, especially those with recurrent bleeding. We also found that radiotherapy could be given to the majority of patients on an out-patient basis in 2 or 3 fractions. This was well tolerated and there were few side effects.  相似文献   
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