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21.
ABSTRACT. The association of zinc and vitamin A levels was studied in liver of foetuses and infants which were stillborn or died of various causes between the age of 26 weeks of gestation up to 16 weeks post-partum. No correlation between zinc and vitamin A was observed ( r =0.07). Although smaller infants had more hepatic vitamin A than larger infants no significant difference was observed between these groups for liver zinc values.  相似文献   
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This pilot study determines fast dynamic gadolinium enhanced MRI contrast enhancement parameters (onset of enhancement and time to peak enhancement) before and after radiotherapy in 10 cervical carcinoma patients. Before radiotherapy, onset of enhancement and time to peak enhancement were early, with a median of 4.5 and 5.2 seconds, respectively. High-grade tumors showed early enhancement, compared with low-grade. After radiotherapy, contrast enhancement patterns differed. In survivors, onset of enhancement after radiotherapy was later than before radiotherapy. In non-survivors, onset of enhancement after radiotherapy was still early. The median difference in onset of enhancement before and after radiotherapy in survivors and non-survivors was an increase of 3.2 and a decrease of 1.1 seconds, respectively. Early onset of enhancement after radiotherapy was a better predictor for survival than a high-signal intensity zone on post radiotherapy unenhanced T1/T2-weighted MRI. It is concluded that enhancement parameters from fast dynamic Gd-enhanced MR images can provide additional functional information with regard to tumor vascularization, and may have prognostic significance. It complements clinical examination and unenhanced MRI in determining the effectiveness of radiotherapy treatment in cervical carcinoma. Future studies will focus on the clinical utility and improvements of the estimation of contrast-enhanced parameters with this new technique.  相似文献   
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Forty one (1%) of 4000 children referred for respiratory disease had chronic suppurative lung disease not due to cystic fibrosis. Further investigations showed congenital malformations in six (15%), primary ciliary dyskinesia syndrome in seven (17%), 11 had immunological abnormalities (27%), and two bronchiectasis due to aspiration (5%). Therefore the underlying cause for the disease was found in 63%. Identification of predisposing causes may facilitate prevention of further bronchial damage.  相似文献   
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Westin S, stensen A I, Lvslett K, Prytz J, Telje J, TelstadW and Lie A. A group-based training programme for general practitioners:a Norwegian experience. Family Practice 1988; 5: 244–252. There are approximately 3000 general practitioners in Norway,serving a population of slightly above four million people.A three year postgraduate education scheme for general practitionershas been in effect since 1973, to be replaced by a five yearvocational training programme from January 1985, making generalpractice a fully recognized specialty from that date. The educationalrequirements consist of one year of hospital training, fouryears of training in general practice, and a total of 400 hoursof course education, mainly in clinical subjects. The core elementof the training is attendance at a group-based structured educationalprogramme of two years' duration. This article describes theconcepts and content of this decentralized group-based education,as well as some of the conflicting considerations which eventuallyled to this new Norwegian model of general practice training.The first evaluation studies indicate that the educational programmehas met a long standing need among general practitioners.  相似文献   
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