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201.
KO Yeates BG Enrile N Loss E Blumenstein DC Delis 《Canadian Metallurgical Quarterly》1995,20(6):801-815
Examined verbal learning and memory in children with myelomeningocele using the California Verbal Learning Test (CVLT). Participants included 41 children with myelomeningocele, 8 to 15 years of age, 33 of whom had a history of shunted hydrocephalus, and 41 matched, unaffected controls. Children with myelomeningocele and shunted hydrocephalus performed worse than controls on the CVLT. They recalled as many words as controls on the first learning trial, but acquired words more slowly across trials, so that their overall recall was lower. Their learning was characterized by a pronounced recency effect. Their delayed recall of the original list was worse than controls, but not their recognition. Performance of children with myelomeningocele but without shunts was generally not significantly different from that of the other two groups, although they did demonstrate better long-delay free recall than children with shunts. Myelomeningocele is associated with significant retrieval problems when accompanied by shunted hydrocephalus. 相似文献
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RJ Price DG Walters C Hoff H Mistry AB Renwick PT Wield JA Beamand BG Lake 《Canadian Metallurgical Quarterly》1996,34(7):603-609
Agaritine [(beta-N-[gamma-L(+)glutamyl]-4-hydroxymethylphenylhydrazine] is present in the common cultivated mushroom Agaricus bisporus and several agaritine derivatives have been shown to produce tumours in experimental animals. In this investigation the metabolism of [ring-U-14C]agaritine has been studied in precision-cut rat, mouse and human liver slices and in precision-cut rat and mouse lung slices. To confirm the functional viability of the tissue slice preparations, the metabolism of 7-ethoxycoumarin was also studied. Liver and lung slices from all species metabolized 50 microM 7-ethoxycoumarin to 7-hydroxycoumarin, which was conjugated with D-glucuronic acid and sulfate. Incubation of rat, mouse and human liver slices, and rat and mouse lung slices with 25 microM [14C]agaritine resulted in a time-dependent formation of metabolite(s), which bound covalently to tissue slice proteins. Agaritine metabolite covalent binding was greater in mouse liver than in rat and human liver slices and was greater in mouse lung than in rat lung slices. No correlation was observed between agaritine metabolite covalent binding and tissue slice gamma-glutamyltransferase activity. Additional studies with mouse liver slices showed that [14C]agaritine was also metabolized to a number of unknown polar metabolites. These results demonstrate that agaritine can be metabolized by enzymes present in mammalian liver and lung. 相似文献
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208.
G Vereb J Sz?ll?si L Mátyus M Balázs WC Hyun BG Feuerstein 《Canadian Metallurgical Quarterly》1996,24(1):64-73
Calcium signaling in non-excitable cells is the consequence of calcium release from intracellular stores, at times followed by entry of extracellular calcium through the plasma membrane. To study whether entry of calcium depends upon the level of saturation of intracellular stores, we measured calcium channel opening in the plasma membrane of single confluent A172 glioblastoma cells stimulated with platelet derived growth factor (PDGF) and/or bradykinin (BK). We monitored the entry of extracellular calcium by measuring manganese quenching of Indo-1 fluorescence. PDGF raised intracellular calcium concentration ([Ca2+]i) after a dose-dependent delay (tdel) and then opened calcium channels after a dose-independent delay (tch). At higher doses (> 3 nM), BK increased [Ca2+]i after a tdel approximately 0 s, and tch decreased inversely with both dose and peak [Ca2+]i. Experiments with thapsigargin (TG), BK, and PDGF indicated that BK and PDGF share intracellular Ca2+ pools that are sensitive to TG. When these stores were depleted by treatment with BK and intracellular BAPTA, tdel did not change, but tch fell to almost 0 s in PDGF stimulated cells, indicating that depletion of calcium stores affects calcium channel opening in the plasma membrane. Our data support the capacitative model for calcium channel opening and the steady-state model describing quantal Ca2+ release from intracellular stores. 相似文献
209.
OBJECTIVES: To determine the endometrial response and bleeding patterns in post-menopausal women who were given a sequential hormone replacement regimen with estradiol 2 mg and dydrogesterone 10 mg. METHODS: One-hundred-and-eighty-eight (188) post-menopausal women with amenorrhea of 6 months or longer, with FSH/estradiol (E2) levels in the post-menopausal range and normal endometrium were entered in the study. All patients received a daily dose of 2 mg E2 during day 1-14 of each 28 day cycle and 2 mg E2 combined with 10 mg dydrogesterone during cycle day 15-28. The total duration of treatment was 12 months (13 cycles of 28 days). RESULTS: The rate of adequate progestational response (secretory or atrophic) in the 146 patients who remained in the study for at least 356 days with 90% study medication compliance and received an endometrial biopsy after 13 cycles of study medication was 97.2%. Three patients had proliferative endometrium and one simple hyperplasia. Cyclic bleedings in the 153 women who remained on study medication for at least 76 days occurred in over 85% of all cycles; the day of onset occurring regularly on day 13 or 14 of the combined period; the mean duration of bleeding per cycle was approximately 5 days with most patients having (very) slight bleeding. Sixty percent of patients had no intermittent bleedings over the whole 12-month study period. The average incidence of intermittent bleeding in the remaining patients was only 2.7 and generally of very slight quantities and of short duration. Per evaluable cycle the percentage of patients with an intermittent bleeding varies from 4.6 to 9.8%. Only two patients discontinued therapy because of bleeding problems. A clear decrease in the incidence of typical menopausal symptoms, i.e. hot flushes and night sweats was observed by the first visit after 6 weeks of treatment. CONCLUSIONS: The endometrial safety of 2 mg E2 sequentially combined with 10 mg dydrogesterone is very good as determined by the histologic response of the endometrium. The incidence of cyclic bleedings with this combination therapy is very high as is the regularity of day of onset and duration of bleeding. Blood loss during intermittent bleedings was mild and of short duration. 相似文献
210.