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Kuntal Patel Deemesh Oudit G Ross Caroline Nicolson AJ Howcroft 《CANADIAN JOURNAL OF PLASTIC SURGERY》2005,13(4):207-208
A lump on the midface of a child can pose as a diagnostic dilemma. There is a wide variety of possible differential diagnoses, ranging from simple benign conditions such as a sebaceous cyst, dermoid cyst, lipoma, neuroma and neurofibroma, to potentially devastating conditions such as odontogenic myxoma.A case of a child in which the formulation of a definite diagnosis was clinically and histologically challenging is presented. 相似文献
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The adenosine-producing ectoenzyme 5'-nucleotidase has recently been shown to undergo a marked redistribution during development of the cat visual cortex and to be involved in the remodelling of ocular dominance columns (Schoen et al., J. Comp. Neurol. , 296 , 379 – 392, 1990). Using an enzyme-cytochemical technique, we now investigate the developmental redistribution of 5'-nucleotidase activity in area 17 of kittens at the ultrastructural level. Between postnatal days 35 and 42, when 5'-nucleotidase is concentrated in layer IV, enzyme reaction product occupies the clefts of asymmetrical synapses within the neuropil. During later development (9th and 13th postnatal weeks), when 5'-nucleotidase spreads over all cortical laminae, the enzyme disappears from its synaptic localization and becomes increasingly associated with astrocytic membranes. The transient appearance of 5'-nucleotidase at synapses parallels the time-course and laminar profile of the synaptic remodelling which takes place during the critical period of visual cortex development. This suggests that synapse-bound 5'-nucleotidase activity plays a role in synaptic malleability, whereas its later association with glial profiles is likely to reflect other functions of the enzyme. 相似文献
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Accuracy and clinical performance of a continuous intra-arterial blood- gas monitoring system during thoracoscopic surgery 总被引:4,自引:2,他引:2
Zollinger A.; Spahn D. R.; Singer T.; Zalunardo M. P.; Stoehr S.; Weder W.; Pasch T. 《British journal of anaesthesia》1997,79(1):47-52
Accuracy and performance of the only currently available intra-arterial
blood-gas monitoring system (Paratrend 7, PT7) were assessed in 23 patients
during thoracoscopic surgery using one-lung ventilation. Over a wide range
of values for arterial PO2 (6.1-61.1 kPa), PCO2 (4.1-9.5 kPa) and pH
(7.19-7.50), 138 arterial blood-gas values obtained by PT7 were compared
with corresponding in vitro laboratory blood-gas measurements. We found
good clinical performance with the PT7 and good agreement between PT7
values and in vitro measurements for arterial PO2 (bias (1.96 SD) = 0.38
(9.52) kPa), PCO2 (0.31 (0.76) kPa) and pH (- 0.017 (0.065)). Also, the
bias for sequential changes between two, consecutive times was not
significantly different from the ideal value of 0. We conclude that the PT7
is helpful in monitoring patients during thoracoscopy.
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A paralysis of the left vocal cord was seen by laryngoscopy in a 3-days-old boy with inspiratory stridor. A ductus aneurysm was established by angiocardiography, which was believed to be the cause of the vocal cord paralysis. Within 8 days after the angiocardiography the aneurysm became smaller and the stridor disappeared. Twelfth months later the control-angiocardiography showed the total obliteration of the ductal aneurysm. 相似文献