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An examination of the urinary excretions of 101 normal subjects indicated that the major genetic influence on calcium excretion is a codominant pair of alleles giving rise to three phenotypes, low, intermediate and high (hypercalciuric) excretors. This inference was based on variance, Hardy-Weinberg and segregation analyses. Similar independent gene pairs also appear to influence oxalate and citrate excretion, A 3-locus Hardy-einberg table using estimates of gene frequencies derived from the study of normals suggests that only 3 or 4 leading genes are involved in oxalate stone disease. Strong candidate genes identified from molecular and physiological studies cannot be proposed at present, but it is assumed that they influence the transport of these ions in either the intestine, kidney or both organs. The identification of the genes involved should be facilitated by the reduction of dietary influences on urinary excretions through the use of formula diets.  相似文献   
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Motoneurons can adapt to altered levels of electrical activity by effecting semi-permanent changes in their neuromuscular synaptic physiology. In the present study, we tested the hypothesis that maintenance of activity-dependent long-term adaptation of synaptic transmission in a crayfish abdominal extensor motoneuron (phasic axon 3) required axonal transport following induction. Intact crayfish were chronically wired for periodic in vivo stimulation of axon 3. Periodic unilateral stimulation for 3-5 consecutive days (2 h/day) induced long-term adaptation (LTA) of neuromuscular synaptic transmission in axon 3. Initial EPSP amplitudes (measured at 0.1 Hz) were significantly reduced to approximately 40% of contralateral control amplitudes over a 7-day poststimulation period. Additionally, synaptic depression during 5 Hz test stimulation of axon 3 was significantly less in chronically stimulated neurons: excitatory postsynaptic potential (EPSP) amplitudes measured after 20 min of 5 Hz test stimulation (final EPSPs) were significantly larger in conditioned neurons than in unstimulated controls. The depression of initial EPSP amplitudes persisted for 7 days postinduction, while the increased synaptic stamina persisted for 4 days but was absent at 7 days postinduction. Axotomy of axon 3 following induction of LTA had no effect on long-term maintenance of the activity-induced reduction in initial EPSP amplitudes. Initial EPSP amplitudes in conditioned, axotomized neurons were still reduced to 42% of control amplitudes over the 7-day postinduction period. In contrast, postinduction axotomy of axon 3 elicited an accelerated decay of the enhanced synaptic stamina. Following axotomy, final EPSP amplitudes were significantly larger in conditioned neurons for only 1 day poststimulation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Data from studies of rankings of acceptability and severity of various disabilities were converted to a common metric of percentile equivalent ranks. A total of 1331 data points from 53 studies yielded the following overall percentile equivalent ranks for 24 disabilities: diabetes (most acceptable), ulcer, arthritis, asthma, heart condition, speech problems, crippled, orthopedic disability, physical disability, amputation, emotional disturbance, appearance disability, deafness, learning disability, stroke, cancer, paraplegia, blindness, epilepsy, tuberculosis, cerebral palsy, mental retardation, mental illness, and multiple disabilities (least acceptable). Rankings of the severity of seven disabilities yielded a somewhat different order that correlated 0.55 with the total data. Rankings of a mild disability were, on average, 40 percentile points higher than rankings for the same disability labeled severe or profound.  相似文献   
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BACKGROUND: Auriculotemporal syndrome (AS) is an uncommon disorder that may present with facial erythema with chewing food. METHODS: We report a patient referred to an allergist to rule out allergy as a reason for food-associated bilateral facial flushing. She was subsequently found to have bilateral AS. RESULTS: The symptoms of AS may overlap those associated with food allergy. There are only a few published cases of bilateral AS. CONCLUSIONS: Allergists should be aware of bilateral AS and the clinical spectrum of this disorder as AS patients may be referred to allergists to rule out food allergy.  相似文献   
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