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151.
152.
K Garde AC Mortensen PB Toft MB S?rensen FF Madsen O Henriksen 《Canadian Metallurgical Quarterly》1994,35(2):197-200
The yeast gene, YTA10, encodes a member of a novel family of putative ATPases. Yta10p, as deduced from the nucleotide sequence, is 761 amino acids in length (predicted molecular mass 84.5 kDa). The amino acid sequence of Yta10p exhibits high similarity to two other yeast proteins, Yta11 and Yta12, and to E. coli FtsH. Several features of Yta10p are compatible with its localization in mitochondria. We report here that Yta10p is a yeast mitochondrial protein and that import is dependent on a membrane potential and accompanied by processing to a protein of approximately 73 kDa. Disruption of YTA10 leads to a nuclear petite phenotype and to a loss of respiratory competence, as shown by spectrophotometric measurement of the activities of respiratory complexes I-III and IV, respectively. These findings together with the high similarity of Yta10p to several ATP-dependent proteases suggest that Yta10p is a mitochondrial component involved, directly or indirectly, in the correct assembly and/or maintenance of active respiratory complexes. 相似文献
153.
MB Chancellor DA Rivas T Linsenmeyer CA Abdill CF Ackman RA Appell J Bennett J Binard TB Boone MP Chetner 《Canadian Metallurgical Quarterly》1994,152(3):924-930
We investigated the effectiveness and associated complications of treatment with an endoluminal urethral sphincter prosthesis in 153 spinal cord injury men (mean age 36 years, range 16 to 74 years) with urodynamically diagnosed detrusor-external sphincter dyssynergia. These patients were prospectively treated with a urethral sphincter stent at 15 centers in North America. Followup ranged from 2 to 33 months. Voiding pressures averaged 76 +/- 28, 42 +/- 21, 44 +/- 38, 35 +/- 18 and 32 +/- 20 cm. water, respectively, before prosthesis insertion in 153 patients and at 3 months in 123, 6 months in 114, 12 months in 98 and 24 months in 22. A significant decrease in voiding pressure was noted in the 22 patients at 24 months compared with matched preoperative data (80 +/- 25 cm. water, p = 0.03). The residual urine decreased from 181 +/- 154 ml. before insertion to 82 +/- 93 ml. at 24 months (p = 0.01). Maximum cystometric capacity remained constant, with a mean of 195 +/- 158 ml. before insertion to 248 +/- 122 ml. at 24 months (p = 0.17). No significant differences were apparent after 24 months of followup in any of the urodynamic parameters between 44 patients with and 109 without previous external sphincterotomy. Hemorrhage requiring blood transfusion, obstructive hyperplastic epithelial overgrowth and soft tissue erosion did not occur. No deleterious effects were observed on renal or erectile function. Of the patients 43 (28.1%) required 2 prostheses to bridge the external sphincter completely. Stent removal was required in 10 patients. Seven explantations were required for prosthesis migration, 1 for pain and urethral edema, 1 for inability to maintain a condom catheter, and 1 for nonepithelialization and secondary bladder neck obstruction. A total of 13 patients (8.5%) required a subsequent operation for bladder neck obstruction. Therefore, the sphincter prosthesis is an attractive modality for the treatment of external sphincter dyssynergia in patients with and without previous external sphincterotomy because of its ease of deployment and minimal associated morbidity. 相似文献
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