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The development of resistance to reinfection with Plasmodium berghei was studied in rats in which the primary infection had been almost totally suppressed by feeding a protein-free diet (peak parasitaemia 0·5%; patent for only the first four days after inoculation). On Days 5, 9, 15, 23 and 28 after primary inoculation groups of animals were challenged with the same strain of parasite. At the same time the diet was changed to that of a 17% casein formula. The development of resistance as judged by the level of parasitaemia following challenge reached a significant level nine days after the primary inoculation and almost complete protection by Day 23 of the study. The protective activity was immunological since it could be transferred to other animals by a single intravenous injection of a suspension of spleen cells from infected donors. The study illustrates that infected animals experiencing severe protein malnutrition are still capable of mounting a substantial immune response to malaria.  相似文献   
63.
Two patients had colonic perforation as a result of percutaneous nephrostomy placement followed by track dilatation and renal calculus removal. We present the technical aspects of nephrostomy placement and stone removal, as well as the clinical diagnosis and management of these cases. Both patients recovered well with conservative therapy and required no surgical intervention. This report reviews the anatomic considerations for percutaneous nephrostomy in patients undergoing renal stone removal.  相似文献   
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Polymorphisms in two genes of Plasmodium falciparum (P. falciparum multidrug resistance 1 [pfmdr1] and P. falciparum chloroquine [CQ] resistance transporter [pfcrt]) are associated with CQ treatment failure. We found significant linkage disequilibrium between these loci among isolates from symptomatic Gambian children (P = 0.026) and strong selection for the resistance-associated alleles pfmdr1-86Tyr and pfcrt-76Thr in children with persistent or re-emerging P. falciparum trophozoites during post-treatment follow-up (P = 1.9 x 10(-7)). Therefore, this genotype is characteristic of resistant infections among our study population. Since the long-term public health impact of parasites carrying such resistant genotypes depends upon their transmissibility, we examined the prevalence of pfmdr1-86Tyr and pfcrt-76Thr among Gambian children harboring sexual stage parasites during post-treatment follow-up. Gametocytes that emerged after successful treatment with CQ were significantly more likely to be of this genotype than were those emerging after other treatments (P = 4.83 x 10(-4)), and were infective to Anopheles mosquitoes. Therapeutic success may thus be accompanied by public health failure as cured children pass resistance genes on to mosquitoes at an enhanced rate.  相似文献   
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A survey of staff attitudes and knowledge about vaginal birth after Caesarean section (VBAC) was undertaken in Australian hospitals. There was a high response rate (67%), and over 900 responses were analysed. Generally, there was a high level of awareness about outcomes and the relative importance of many issues in considering VBAC. Registrars, consultants and midwives differed significantly in some aspects of their knowledge and attitudes to VBAC. There was also a wide range of opinion within each group. Approximately half (53%) of respondents believed patients should be actively encouraged to consider VBAC, whereas 47% felt it should be simply presented as an option.  相似文献   
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The hormonal and metabolic response to the first feed of breast milk was studied in 12 infants at 4-6 hours of age. After the feed there was an increase in blood glucose concentration but no changes in the concentrations of lactate, pyruvate, alanine, or ketone bodies. The feed was followed by an increase in the concentrations of plasma insulin, growth hormone, gastrin, and enteroglucagon, but no change in levels of plasma glucagon or gastric inhibitory peptide. Several hormone systems are functionally active at birth and are stimulated by the first feed of milk.  相似文献   
69.

Background  

Indo-Asians in Canada are at increased risk for cardiovascular diseases. There is a need for cultural and language specific educational materials relating to this risk. During this project we developed and field tested the acceptability of a hypertension public education pamphlet tailored to fit the needs of an at risk local Indo-Asian population, in Calgary, Alberta, Canada.  相似文献   
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