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Spontaneous perforation of the esophagus is an uncommon and catastrophic event accompanied by extremely high morbidity and mortality. In a burn patient, diagnosis may be delayed because of painful burns that may mask the underlying problem. Diagnosis is dependent on a high index of suspicion and by inclusion of this entity in the differential diagnosis of chest pain. The authors report on a 45-year-old male who developed a spontaneous perforation of the esophagus while hospitalized for treatment of an 11% total body surface area burn. Diagnosis and initiation of appropriate treatment resulted in salvage of this patient. The pathophysiology of this disease and a review of the literature are presented.  相似文献   
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The cost effectiveness of several modes of family planning service delivery based on the cost per couple-year of protection (CYP), including commodity costs, is assessed for 1991-92 using programme and project data from fourteen developing countries (five in Africa, four in Asia, three in Latin America and two in the Middle East). More than 100 million CYP were provided through these family planning services during the 12 months studied. Sterilisation services provided both the highest volume (over 60% of total) and the lowest cost per CYP ($1.85). Social marketing programmes (CSM), delivering almost 9 million CYPs, had the next lowest cost per CYP on average ($2.14). Clinic-based services excluding sterilisation had an average cost of $6.10. The highest costs were for community-based distribution projects (0.7 million CYPs), which averaged $9.93, and clinic-based services with a community-based distribution component (almost 6 million CYPs), at a cost of $14.00 per CYP. Based on a weighted average, costs were lowest in the Middle East ($3.37 per CYP for all modes of delivery combined) and highest in Africa ($11.20).  相似文献   
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In patients undergoing somatostatin receptor scintigraphy, treatment with octreotide (Sandostatin) is usually discontinued 24-48 h before and after injection with the radioligand 111In-pentetreotide ([111In-DTPA(O)]octreotide) (Octreoscan) because octreotide competes with radioligand for the same receptors. However, D?rr et al. and Soresi et al. reported improved visualization of carcinoid and small cell lung cancer lesions, respectively, during continued octreotide treatment. We found that intravenous administration of unlabeled octreotide to rats inhibited the binding of an optimal dose (0.5 microg) of 111In-pentetreotide to somatostatin receptors in pancreas and adrenals in a mass- and time-dependent way. Pretreatment with unlabeled octreotide never increased receptor binding of 111In-pentetreotide. Administration of 100 microg of octreotide decreased receptor-bound radioactivity if given simultaneously with or 10 or 20 min after injection of the radioligand, but had no effect if given 30 min after the radioligand. These findings indicate rapid processing of receptor-bound octreotide and suggest that octreotide treatment of patients undergoing 111In-pentetreotide scintigraphy may be reinitiated as soon as 1 h after radioligand administration.  相似文献   
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Aplasia/hypoplasia of the patella has been described as an isolated finding or, more commonly, as a part of congenital syndromes. We describe here bilateral absence of the patella in an 11-year-old girl with absence of the ischial and inferior pubic rami bilaterally. Other associated skeletal and soft-tissue deformities are also reported. To our knowledge, the constellation of these findings has not been described previously and represents a unique syndrome.  相似文献   
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Trinucleotide repeats in several human genes have been found to undergo spontaneous variation in repeat numbers in succeeding generations. Expansion of the repeat beyond a certain length causes specific pathological disorders. So far, a naturally occurring triplet repeat instability of transcribed sequences has been reported only from humans. However, the signal peptide encoding region of the receptor tyrosine kinase gene Xmrk from fish of the genus Xiphophorus contains a CTG repeat that differs in length even between closely related individuals. The consequence of this variability is signal peptides with shorter or longer hydrophobic core regions reaching, in some individuals, the critical maximum length for functional protein export or even exceeding it. In one stock, animals that are homozygous for such an allele were extremely rare, indicating that the triplet repeat length variability of the Xmrk gene of Xiphophorus may indeed have an influence on the function of the gene product and, under certain conditions, may affect the fitness of the individual.  相似文献   
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