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Bilateral ovarian fibromas in children   总被引:1,自引:0,他引:1  
The case of bilateral ovarian fibromas occurring in an 8-year-old black girl is reported. These lesions occur rarely in premenarchal females and may be a manifestation of Nevoid Basal Cell Syndrome. Calcifications are reported to occur rarely in ovarian fibromas but seem to occur frequently in fibromas in children. Management is guided by the benignity of the lesion and consists of surgical excision of the fibroma. Preservation of normal ovarian tissue is recommended with the acknowledged risk of recurrence of the fibroma.  相似文献   
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The skeletal remains of past populations provide an important source of information on the natural history of disease. Relatively few cases of bone tumours have been reported in archaeological material. This paper describes one of the oldest occurrences of osteochondroma to have been identified in a human skeleton.  相似文献   
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Autoradiographic techniques were used to test if positive modulators of AMPA-type glutamate receptors have regionally differentiated effects on ligand binding. Cyclothiazide, a drug with ten fold greater effects on `flip' than `flop' splice variants of the receptors, had unequal effects across the subdivisions of hippocampus; i.e., it reduced [3H]AMPA binding in field CA3 with an EC50 of 24 μM and in field CA1 and dentate gyrus with EC50s between 60 and 100 μM. The EC50 for the drug's influence on binding was also significantly lower in the superficial than in the deeper layers of the neocortex, though these differences were not as pronounced as those in the hippocampus. The ampakine CX614, a compound with a modest preference for flop variants, had a slightly lower EC50 for its effects on [3H]AMPA binding in CA1 than in CA3. This result was confirmed with [3H]fluorowillardiine binding. The effects of the ampakine in neocortex tended to be greater in the deeper than superficial layers but this did not reach statistical significance. These results indicate that differential effects of modulators on AMPA receptor subunits are reflected in their relative potency across brain subdivisions. This raises the possibility that subclasses of positive modulators will exhibit a measurable degree of selectivity in their physiological and behavioral influences.  相似文献   
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Abdominal complications of intestinal surgery are an important cause of postoperative morbidity and mortality. We define early complications as those occurring within the first 30 days after surgery. The radiological contribution towards prompt and accurate diagnosis of common complications is discussed and the radiologist's role in non-operative management is outlined.  相似文献   
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The bleeding problems experienced by users of subdermal levonorgestrelimplants (Norplant) remain unexplained. The aim of the presentstudy was to investigate the oestrogen (ER) and progesteronereceptor (PR) distribution in levonorgestrel-treated endometrialbiopsies from 31 subjects recruited in Jakarta, Indonesia, andto compare the sex steroid receptor immunostaining with thatof endometrium from 58 normally cycling women from Melbourne,Australia. Sex steroid receptor immunoreactivity was additionallycompared with days of exposure to subdermal levonorgestrel,serum oestradiol and progesterone levels and days of bleedingduring a 90-day reference period. An immunohistochemical techniquewith an alkaline phosphatase anti-alkaline phosphatase (APAAP)detection system for use in formalin-fixed paraffin wax embeddedendometrial tissue was employed. Significantly greater meanimmunostaining scores of stromal PR were observed in Norplantcompared with control endometrium at all stages across the cycle.No significant correlations were demonstrated between sex steroidreceptor immunostaining and days of exposure to subdermal levonorgestrel,serum oestradiol or progesterone concentrations or days of bleedingduring a 90-day reference period. Whether the elevated stromalPR immunostaining in Norplant-treated endometrium is a consequenceof increased synthesis or reduced turnover of receptor remainsunclear. As yet it is undetermined whether increased PR immunoreactivitycorresponds to an increase in number of functional PR.  相似文献   
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