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Q Wang BN Zhou RW Zhang YY Lin LZ Lin RR Gil GA Cordell 《Canadian Metallurgical Quarterly》1996,62(2):166-168
A 10-year-old left-handed girl with a developmental stutter and agenesis of the corpus callosum with associated hydrocephalus ceased stuttering immediately upon initiation of steroid therapy for colitis. Steroid taper resulted in a recurrence of the stutter and resumption for treatment of recrudescent colitis caused its disappearance again. Baseline agenesis of the corpus callosum with hydrocephalus and the patient's course in the face of the known effects of steroids on white matter lend support to the hypothesis that stuttering reflects anomalous dominance and/or atypical interhemispheric connectivity, as evidenced by the fact that presumed alterations of white matter tracts affected speech rhythms/stuttering. 相似文献
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12 hearts with Ebstein's anomaly were studied. This disease is a combined anomaly of heart formation with dysplasia of the folds of the tricuspid valve (TV), its tendinous chordas and papillary muscles, dysplasia of the trabecular part of the right ventricle and dysplastic interrelationships between TV and the right ventricle: attachment by short chordas of posterior and septal folds of TV with the right ventricle walls, anomalous distal attachment of the anterior fold of TV. "Atrialisation" of the right ventricle is the reflection of the folds dysplasia the extreme form of which is the loss of communication between TV and trabecular part and formation of the direct communication between TV and the infundibular part of the right ventricle. 相似文献
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There is a lack of information in the United Kingdom on the prevalence of third molars in older patients. The aim of this study was therefore to define the pattern of lower third molar retention in UK dental practice attenders aged 35 years and over. A random sample of 599 eligible patients from a rural dental practice were included in the study. Information was obtained from clinical notes and panoramic radiographs. Data collected included age, gender, presence or absence of lower third molars, number of teeth present in the lower arch and eruption status. Two hundred and sixty-four (44.1 per cent) had at least one lower third molar present (mean age = 57.1 years) while 335 (55.9 per cent) had no lower third molars (mean age = 50.2 years). The data suggest that a greater proportion of men than women retain at least one lower third molar although this finding was not statistically significant. Seventy per cent of retained lower third molars reported in the study were fully erupted. Sixty per cent were vertically placed. There was an association between age and number of teeth present (chi 2 = 38.85, 4DF, P < 0.05), older patients having fewer lower teeth. These data suggest that a large number of patients can expect to keep their lower third molars beyond the age of 35 years and that in many cases a conservative "wait and see' policy for lower third molars in the early twenties is appropriate. 相似文献
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After incubation of separate zones of rat adrenals with radioactively labelled serotonin--at concentrations at which the amine had been previously shown to stimulate aldosterone biosynthesis--the tissue radioactivity was several times higher in the capsular ("zona glomerulosa") than in the decapsulated portions of the glands. High doses of unlabelled serotonin diminished the accumulation of radioactivity, but only when added simultaneously with the tracer. In the course of the incubation, radioactive 5-hydroxy-3-indoleacetic acid, i.e. the deaminated metabolite of serotonin, rapidly appeared in the medium. Most of the radioactive material accumulated by the adrenal was recovered in the cytosol fraction and was no longer identical with serotonin, but consisted mainly of 5-hydroxy-3-indoleacetic acid and another, unidentified metabolite. Unaltered serotonin was found in capsular adrenal tissue extracts only when a monoamine oxidase inhibitor (nialamide) has been added to the incubation medium. Rapid uptake and metabolism thus appeared to be the predominant features of the interaction of incubated adrenal tissue with serotonin. These events may have obscured the possible binding of very small amounts of serotonin to receptor sites. The observed accumulation of radioactivity in adrenal tissue was mainly due to delayed outflow of intracellulary formed metabolite, since 5-hydroxy-3indoleacetic acid was neither taken up by incubated adreanls nor bound by adrenal cytosol. No evidence of serotonin storage in the zona glomerulosa was found in these studies. 相似文献
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In situ vascular endothelium is characterized by many cytoplasmic vesicles (caveolae) and vacuoles. In venules these are organized into prominent clusters called vesiculo-vacuolar organelles or VVOs. VVOs provide an important pathway for plasma protein extravasation in response to vasoactive mediators. In contrast, cultured endothelial cells isolated from many sources lack VVOs and generally have few caveolae. Our goal was to preserve VVOs in cultured endothelium. Bovine adrenal microvascular endothelial cells (BCEs) cultured on floating Matrigel-collagen Type I gels with vascular permeability factor/vascular endothelial growth factor (VPF/VEGF) exhibited typical VVOs by electron microscopy. Both in vivo and in culture VVOs were caveolin-positive by immunoelectron microscopy. On the basis of caveolin immunostaining, VVOs could also be detected by light (confocal) microscopy. When BCEs were cultured without VPF/VEGF, caveolin staining was finely punctate and electron microscopy confirmed the near absence of VVOs. BCE VVOs were sensitive to N-ethylmaleimide. Other types of endothelium cultured on Matrigel-collagen gels with or without VPF/VEGF exhibited few caveolae and no VVOs. Therefore, preservation of VVOs in cultured endothelium required a specific combination of endothelial cells (BCEs), surface matrix (Matrigel-collagen), and growth factor (VPF/VEGF). These endothelial cells should be useful for in vitro studies of trans-endothelial transport. 相似文献