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991.
Contact diode laser myringotomy and mitomycin C in children   总被引:1,自引:0,他引:1  
OBJECTIVE: To investigate the use of contact diode laser myringotomy (C-LAM), combined with topical mitomycin C, as an alternative method for prolonged middle ear ventilation in children with otitis media with effusion. STUDY DESIGN AND SETTING: Prospective study at a tertiary care pediatric institution. METHODS: Fifteen children enrolled in the study. Mitomycin C was applied to the intact tympanic membrane in the right ears, whereas saline on the left side was used for controls. C-LAM was then performed in all ears. Outcome measures included healing rate and scarring, ear infection, and long-term audiometric follow-up. RESULTS: There was no significant difference in median healing rate. In each group, the median was between the third and fourth month. Normal hearing thresholds were obtained in all children at 2-year follow-up. CONCLUSION: C-LAM proved to be an effective method for medium-term ventilation, but topical mitomycin C before C-LAM did not prolong patency rate in our patients. No significant complication was encountered at 2-year follow-up.  相似文献   
992.
993.
PURPOSE: To examine the application of statistical parametric mapping (SPM) to analyze ictal single-photon emission computed tomography (SPECT) scans in surgical candidates with extratemporal lobe epilepsy. METHODS: The authors selected patients who underwent successful ictal SPECT acquisition in the process of surgical treatment of intractable partial epilepsy. Thirteen patients were identified who met inclusion criteria for confident seizure localization from either intracranial electroencephalogram recordings or epilepsy surgery outcome. In these cases, ictal scans were registered to an in-house-developed normal SPECT atlas composed of 14 spatially normalized brains of normal subjects. SPM96 was used to test on a voxel-by-voxel basis for statistically significant increases in blood flow associated with each patient's ictal scan. The results were then mapped back onto the patient's magnetic resonance image (MRI) for final interpretation. Statistical parametric mapping (SPM) analysis of ictal SPECT scans was compared to both conventional visual interpretation and the analysis of subtraction ictal SPECT co-registered to MRI (SISCOM). RESULTS: Ten of 13 patient scans showed localizing focal ictal increases in regional cerebral blood flow, all of which were concordant with ultimate epilepsy localization. Of the 3 cases not localized with SPM, 1 was localized by conventional visual interpretation and another, not localized by visual interpretation, was correctly localized with SISCOM. Two cases not localized by SISCOM were localized by both visual and SPM analysis. CONCLUSIONS: This work provides supportive evidence for proof of principle that SPM can be used to provide objective, accurate analysis of ictal SPECT scans in patients with extratemporal lobe epilepsy.  相似文献   
994.
995.
In 1993 it was reported that sensory nerve axons enter myocutaneous flaps from all sides of the wound bed through empty perineural tubes, suggesting that small flaps (because less tissue must be reinnervated) and old flaps (because the regenerating process should be completed) would have the best sensation. However, sensory recovery is correlated with neither the flap size nor their age. Since all 16 flaps in this study were placed on significantly traumatized limbs, scar formation should hinder sprouting axons from entering the flap; the present study was performed to test this hypothesis. The sensation of 16 myocutaneous flaps (group A) placed in a nontraumatized wound bed was compared to that of patients in a previous study (group B). All 32 flaps were tested for pin-prick, hot, cold, 30-Hz, 256-Hz vibration, constant touch, moving two-point discrimination, and static two-point discrimination. The results were rated as follows: 2 points for a modality being present all over the flap, 1 for its partial or dull presence, and 0 for no sensation. The elapsed time following surgery was 1.10 –5.40 years in group A and 1.50–8.20 years in group B. Patients in group A scored a mean score of 8.0±2.1 points (4–11) and those in group one of B 5.9± 4.8 (0–13). There was a significant correlation between score and flap age in group A but not in group B; there was no correlation in either group between score and the flap size. Our findings suggest that scar formation is detrimental to the capacity for sensory recovery in myocutaneous flaps. Maximum scar tissue excision is recommended, especially since sensory recovery is not less than in large flaps.  相似文献   
996.
Regeneration of human liver was long suspected to occur. It was proven in animals 100 years ago but could not be demonstrated in man until liver biopsy and modern hepatic tests became available. Structural changes in the regenerating liver mainly concern the arrangement of liver cell plates and the size and appearance of hepatocytic nuclei. A return to normalcy in test results depends on the factors responsible for regeneration since various test results change at different rates. Mass, estimated by imaging procedures, is restored parallel with the return of function. Shape is not restored but the pressure of neighboring organs and structures molds the growing remnant so that it almost resembles the original. Factors regulating regeneration in man are beginning to be recognized as they have been in animals. The hope is that regeneration can be accelerated or that cells can be transplanted to replace those lost.  相似文献   
997.
998.
999.
Dactylolysis spontanea is an idiopathic condition affecting the fifth toe, and sometimes other toes, that is frequently bilateral, with lesions in different stages. Between 1977 and 1999, a total 6000 radiographic studies of the feet were reviewed in a mainly African American population in Chicago, Illinois. After an initial screening based on the Cole criteria, 581 patients were selected and re-examined, and amplification techniques were performed. After reviewing the complementary exams, 102 patients were diagnosed with dactylolysis spontanea or ainhum. Soft-tissue constriction was the most frequently presented radiological sign on the initial screening. Kurtosis at the digit plantar fold and marked rotation of the fifth toe were normal findings in asymptomatic patients. Demographics, comorbidities, and radiological findings were analyzed in the selected population. Associated diseases occurring in these patients appeared to have no specific etiologic correlation with ainhum. African Americans and the dark-skinned population are affected exclusively by this condition, presumably due to the fibrogenic tendency of these individuals. Early diagnosis and accurate staging of ainhum are facilitated by radiological examination of the feet. The findings suggest that this condition is underdiagnosed and overlooked because its low prevalence and variable clinical presentations that might mimic more common etiologies, including localized trauma.  相似文献   
1000.
Recent steps to prevent neonatal sepsis due to group B Streptococcal infection have lowered the attack rate from this organism, but may not have lowered overall sepsis rates. Mortality from sepsis stills remains between 20 and 40% and is probably so high due to the immunological immaturity of the newborn. Although antibiotics remain the mainstay for treatment, adjunctive therapies aimed at improving the immunological integrity of the neonatal patient have a role in treatment and may improve outcomes. We discuss several adjunctive therapies, along with the physiologic rationale for their use, and discuss an approach for their inclusion in therapy for neonatal sepsis.  相似文献   
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