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971.
972.
973.
Forty-five children with stable chronic renal failure, not on dialysis, were treated conservatively with a regimen of mild dietary phosphate restriction and high-dose phosphate binders for up to 5 years. Both aluminum hydroxide and calcium carbonate were used initially, but almost all patients were taking calcium carbonate towards the end of the period. Serum immunoreactive parathyroid hormone concentrations were significantly decreased and were within the normal range after 1 year and remained normal during treatment. There was no significant change in renal function over the same treatment period. We conclude that calcium carbonate should be used as the phosphate binder of choice in the long-term suppression of hyperphosphatemia and hyperparathyroidism in uremic children.  相似文献   
974.
What have we learnt from mouse models of NPM-ALK-induced lymphomagenesis?   总被引:1,自引:0,他引:1  
S D Turner  D R Alexander 《Leukemia》2005,19(7):1128-1134
The nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) is generated as a t(2;5) chromosomal breakpoint product, typically in CD30(+) anaplastic large cell lymphomas. Activation of the NPM-ALK tyrosine kinase by NPM dimerisation causes autophosphorylation at multiple tyrosine residues and the consequent recruitment of a 'signalosome' that couples the fusion protein to pathways regulating mitogenesis and apoptosis. This review focuses on recent advances in our understanding of the transforming signals induced by this fusion protein in mouse models.  相似文献   
975.
Patients who suffer from epiphora can benefit from reconstructive surgery in many cases of obstructive and nonobstructive lesions of the lacrimal apparatus. We describe our technique of digital subtraction macrodacryocystography (DSM) and discuss its efficacy in the evaluation of various abnormalities involving the lacrimal drainage pathway. A variety of pathologic conditions of the lacrimal apparatus are portrayed. DSM is an accurate, easy to perform, but relatively unrecognized method of anatomic localization of obstructive lesions within the lacrimal drainage system.  相似文献   
976.
977.
The effects of halothane, tetrodotoxin (TTX), veratridine (VTD), and alterations of extracellular calcium ion concentration [Ca++]0) on regional differences of canine Purkinje fiber action potential duration (APD50 and APD90) were investigated in vitro at a paced rate of 75 beats per min. Under control conditions (n = 15 hearts) APD90 of proximal (false tendon) fibers (289 +/- 6 ms) always exceeded (P less than or equal to 0.01) that of distal (apical) fibers (213 +/- 4 ms). Halothane (0.35-1.07 mM) reduced regional differences of APD90 by producing dose-dependent decreases of proximal APD90 without decreases of distal APD90. The regional actions of halothane were similar to those of low (0.33-1.0 microM) concentrations of the Na+ channel antagonist TTX, which also decreased proximal APD90 more than distal APD90. The actions of halothane in combination with TTX further decreased proximal APD90, whereas the Na+ channel agonist VTD, which increased proximal APD90 more than distal APD90, reversed the regional actions of halothane. Decreasing Ca++ influx by reducing [Ca++]0 from 1.8 to 0.6 mM increased proximal APD90 more than distal APD90 in a manner opposite to the regional actions of halothane. Although there was no difference between the values of APD90 obtained for each region in the presence of halothane at 0.6, 1.8, and 3.6 mM [Ca++]0, the action of halothane decreasing APD90 of proximal fibers was more prominent at 0.6 mM [Ca++]0 because of the increased APD90 of fibers under this condition. The findings are consistent with, but do not definitively prove, the hypothesis that halothane may decrease APD90 of proximal Purkinje fibers by a mechanism similar to that of TTX involving inhibition of plateau-phase inward Na+ current.  相似文献   
978.
An 18-year-old patient who had recurrent attacks of acute pancreatitis was found on endoscopic retrograde cholangiopancreatography to have an aberrant pancreatic duct which communicated with a juxtagastric cyst. Excision of a gastric antral duplication cyst and the aberrant pancreas was curative. Of the five previously reported cases, none of which had endoscopic retrograde cholangiopancreatography before surgery, all but one required multiple operations before the correct diagnosis was made.  相似文献   
979.
980.
This case study describes a treatment developed for an obsessional patient for whom neither in vivo nor verbal exposure was effective in eliciting obsessional thinking. The treatment consisted of increasingly more strict temporal parameters the patient was to impose when obsessional thoughts spontaneously occurred. These parameters stipulated the amount of time he was to wait between the occurrence of obsessional thoughts and compulsive checking, and the amount of time he was to spend checking. Over a period of several months, these self-imposed temporal parameters were effective in completely eliminating persistent and intractable obsessional thinking of 11 years' duration.  相似文献   
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