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Parotidectomy may be associated with a significant depression in the retromandibular region and a significant incidence of gustatory sweating (Frey's syndrome). Superiorly and inferiorly based sternocleidomastoid flaps and posterior plication of the superficial musculoaponeurotic system were evaluated for their ability to ameliorate both consequences. Sixteen patients with sternocleidomastoid flaps and 16 patients with superficial musculoaponeurotic system plication were compared to a control group of 104 patients. The incidence of Frey's syndrome was 47.1% in the control group, 12.5% (P = 0.025) in the sternocleidomastoid flap group, and 0% (P = 0.005) in the superficial musculoaponeurotic system plication group. The surgical techniques are described. The prevalence of Frey's syndrome is discussed with respect to age, sex, radiation therapy, and the type of parotidectomy performed. The indications and contraindications of the three surgical techniques are described.  相似文献   
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This report of the North American Pediatric Transplant Cooperative Study summarizes data contributed by 57 participating centers on 754 children with 761 transplants from 1 January 1989 to 16 February 1989. Data collection was initiated in October 1987 and follow-up of all patients is ongoing. Transplant frequency increased with age; 24% of the patients were less than 5 years, with 7% being under 2 years. Common frequent diagnoses were: aplastic/dysplastic kidneys (18%), obstructive uropathy (16%), and focal segmental glomerulosclerosis (12%). Preemptive transplant, i.e., transplantation without prior maintenance dialysis, was performed in 21% of the patients. Dialytic modalities pretransplant were peritoneal dialysis in 42% and hemodialysis in 25%. Bilateral nephrectomy was reported in 29%. Live-donor sources accounted for 42% of the transplants. Among cadaveric donors, 41% of the donors were under 11 years old. During the first post-transplant month, maintenance therapy was used similarly for live-donor and cadaver source transplants, with prednisone, cyclosporine, and azathioprine used in 93%, 83%, and 81%, respectively. Triple therapy with prednisone, cyclosporine, and azathioprine was used in 78%, 75%, and 75% of functioning cadaver source transplants at 6 months, 12 months, and 18 months as opposed to 60%, 63%, and 54% for live-donor procedures, with single-drug therapy being uncommon. Rehospitalization during months 1–5 occurred in 62% of the patients, with treatment of rejection and infection being the main causes. Additionally, 9% were hospitalized for hypertension. During months 6–12 and 12–17, 30% and 28% of the patients with functioning grafts were rehospitalized. Times to first rejection differed significantly for cadaver and live-donor transplants. The median time to the first rejection was 36 days for cadaver transplants and 156 days for live-donor transplants. Overall, 57% of treated rejections were completely reversible although the complete reversal rate decreased to 37% for four or more rejections. One hundred and fifty-two graft failures had occurred at the time of writing, with a 1-year graft survival estimate of 0.88 for live-donor and 0.71 for cadaver source transplants. In addition to donor source, recipient age is a significant prognostic factor for graft survival. Among cadaver donors, decreasing donor age is associated with a decreasing probability of graft survival. Thirty-five deaths have occurred; 16 attributed to infection and 19 to other causes. The current 1-year survival estimate is 0.94. There have been 9 malignancies.A list of all participating centers and the names of the investigators is printed on pages 552–553  相似文献   
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Cells of Escherichia coli deleted for genes that code for the transducers and all the known cytoplasmic Che proteins except CheY responded reversibly to the addition of acetate by spinning their flagellar motors clockwise. By varying growth conditions and using metabolic inhibitors and mutants deficient in acetate metabolism, this effect was shown to require acetate-CoA synthetase [acetate:CoA ligase (AMP-forming); EC 6.2.1.1], an enzyme that catalyzes the formation of acetyl-CoA from acetate by an acetyladenylate intermediate. A mutant deficient in this enzyme but retaining the chemotaxis genes was deficient for chemotaxis. Thus, acetyladenylate appears to play a role in generating clockwise rotation at the level of CheY or the motor.  相似文献   
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C L Conley 《JAMA》1990,263(18):2481-2483
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