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81.
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Revision chronic ear surgery.   总被引:6,自引:0,他引:6  
OBJECTIVE: To report results of revision chronic ear surgery following guidelines of the American Academy of Otolaryngology-Head and Neck Surgery and to establish expectations for infection and cholesteatoma control and hearing outcomes. STUDY DESIGN: Retrospective case review of all patients who underwent revision chronic ear surgery from January 1, 1990 to December 31, 2000. Revision chronic ear surgery included canal wall up and canal wall down procedures with ossicular chain reconstruction performed as needed. Cholesteatoma control, hearing improvement, and closure of middle ear space are main outcome measures. SETTING: Tertiary referral center. RESULTS: Cholesteatoma recurrence rate was 57% at 1 year after surgery and 14% in patients with a minimum of a 5-year follow-up. Disease control was achieved in 96% of patients. Hearing was significantly improved in all surgical groups. Closure of the air-bone gap for revision partial ossicular replacement prosthesis cases (PORP) to less than 20 dB occurred in 50% of patients. Closure of the air-bone gap to within 30 dB for revision total ossicular replacement prosthesis (TORP) occurred in 60% of patients. Canal wall down status had a significant impact on hearing results after PORPs and TORPs; patients with intact canal walls had significantly better hearing results. Diagnosis of cholesteatoma significantly impacted hearing results for TORPs but not PORPS. CONCLUSIONS: Cholesteatoma control rates after revision surgery are similar to primary cases. Significant improvement in hearing can be expected after revision chronic ear surgery. Hearing results after a revision surgery that requires a PORP is worse than primary cases and is canal wall status dependent. Closure of the middle ear space and creation of a safe dry ear can be expected after revision chronic ear surgery. SIGNIFICANCE: This is a review of a large series of exclusively revision chronic ear surgery. EBM rating: C-4.  相似文献   
83.
Since bone marrow has been shown to contain osteoprogenitor cells, an experiment was devised to test its effects when injected percutaneously into osteotomies and 2-cm bony defects produced in rabbit radii. The parameters tested included callus volume, breaking load, tensile strength, and cross-sectional area of callus at the fracture or bony defect site. At two weeks postgrafting callus volume was significantly higher (p less than 0.01) in the grafted radii than in the contralateral saline controls. By four weeks all four parameters were significantly greater in the bone marrow grafted radii than in the contralateral saline controls. Serial radiographs and histology confirm this advanced fracture healing in the grafted bones. The earlier and more abundant callus, at the bone marrow grafted sites, was felt to provide earlier and greater stability, resulting in decreased early healing time when contrasted with the saline controls. Similarly, the bony defects that were grafted with bone marrow united by a bony bridge, whereas the saline controls did not. Percutaneous bone marrow grafting is a simple semi-invasive technique that may have potential clinical applications.  相似文献   
84.
The VII-XII anastomosis has been employed for more than a decade by The Otology Group, P.C., in the facial reanimation of patients undergoing extirpation of tumors involving the cerebellopontine angle and the skull base. A retrospective review based upon a detailed questionnaire and submitted photographic documentation from 61 patients forms the basis for this review. Details and analysis of the functional results include onset of function, synkinetic activity, corneal irritation and associated ophthalmologic problems, facial tone and symmetry, and volitional mimetic function. From a psychosocial perspective, evaluation was made regarding workplace and home acceptance, self consciousness, adaptation, and overall satisfaction. Because of the nature of its technical performance and reliability, the VII-XII anastomosis is an important technique for the otolaryngologist to be familiar with. Cognizance of the functional and psychologic results with this procedure will ensure optimal (yet realistic) rehabilitation for this patient population.  相似文献   
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Summary The clinical features and histological appearance of desmoplastic malignant melanoma are presented. Aggressive surgical management and close follow-up are mandatory if this highly aggressive tumor is to be controlled. Despite this, the prognosis is poor.  相似文献   
88.
STUDY OBJECTIVE: To determine the effect of baseline complex ovarian cysts on controlled ovarian hyperstimulation and in vitro fertilization (IVF) outcome. DESIGN: Retrospective analysis with stratification by stimulation regimen and the presence or absence of surgically documented endometriosis. PATIENTS: Two hundred sixty-one women undergoing IVF from May 1, 1989 to December 31, 1990. MAIN OUTCOME MEASURES: The outcome measures assessed were the maximum estradiol (E2) concentration on day of human chorionic gonadotropin (hCG) administration, number of follicles with maximum diameter greater than or equal to 15 mm, number of follicles with maximum diameter greater than or equal to 12 mm, number of days to hCG administration, number of ampules of human menopausal gonadotropin (hMG) used, number of oocytes retrieved and fertilized, number of embryos transferred, and pregnancy and cycle cancellation rates. RESULTS: There were no statistical differences between cyst and noncyst groups in any of the above parameters of IVF performance. In a single subgroup, patients with endometriosis stimulated with hMG and patients with cysts had significantly lower E2 concentrations than patients without cysts. CONCLUSION: The presence of a complex cyst on a baseline ultrasound does not appear to adversely affect IVF cycle outcomes.  相似文献   
89.
Summary Immunogold electron microscopy revealed that site-specific antibodies elicited by a synthetic peptide representing the N-terminal sequence (residues 2–10) of influenza virus M 2 protein were capable of binding to the surface of virions. Antibody binding was observed with two human influenza virus strains but not with an avian virus strain which has amino acid substitutions in the appropriate sequence of M 2. These results provide direct evidence for the presence of M 2 in the influenza virion.  相似文献   
90.
We describe an improved radio-enzymatic method for the measurement of carnitine, short-chain acyl-carnitine and long-chain acyl-carnitine in plasma and tissue. An internal standard, hexadecanoyl-[CH3-3H]-carnitine was synthesised and used to improve the determination of long-chain acyl-carnitine. The between and within batch precisions were 10.4 and 7%, respectively. Control data for neonates, infants, children and adults in the fed and fasted state are documented. In addition we confirm the hypocarnitinaemia associated with pregnancy. Patients with medium-chain acyl-CoA dehydrogenase deficiency were studied during episodes of hypoglycaemia. In both fasted controls and patients there were high concentrations of short-chain acyl-carnitine, however in the latter group there were also low concentrations of free carnitine. We suggest that the monitoring of plasma carnitine and its derivatives is a useful adjunct to the investigation of children suspected to suffer from inherited disorders of mitochondrial beta-oxidation. We also describe a sample preparation procedure suitable for high performance liquid chromatographic analysis of specific acyl-carnitines from urine, plasma and tissue homogenates. The recoveries of acetyl-carnitine, octanoyl-carnitine and hexadecanoyl carnitine from urine were 101.5, 95 and 91% and from plasma 99.5, 91.5 and 85.5%, respectively. Acyl-carnitines (C2-C16) were analysed as their p-bromophenacyl derivatives by reverse-phase high performance liquid chromatography using a ternary gradient of acetonitrile/water/triethylamine phosphate. We report ten patients who excreted octanoyl-carnitine, hexanoyl-carnitine and in some cases a small amount of decanoyl-carnitine. In most of these cases suberylglycine and dicarboxylic acids were also detected by GC/MS. We had access to cultured fibroblasts from five of these patients and were able to demonstrate medium-chain acyl-CoA dehydrogenase deficiency by direct enzyme assay.  相似文献   
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