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Stent insertion for bronchial stenosis has become common practice in lung transplantation and advanced lung malignancy, and for external compression of the airways for other reasons. Right main bronchus stenting may require blocking the right upper lobe by the stent, placing the patient at risk of recurrent pneumonia and atelectasis. In this study, three patients after insertion of a metal stent to the right main bronchus are described. In all cases, the right upper lobe was covered by the stent, and a laser (Nd:YAG) procedure was used to open a 'window' in the stent toward the right upper lobe with a follow-up of 1 year. We conclude that stent insertion to the right main bronchus may be followed by a laser therapy to open a 'window' toward the right upper lobe.  相似文献   
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BACKGROUND: Evidence of increased asthma and allergic response among urban versus rural residents has been reported. OBJECTIVE: To evaluate the prevalence of allergic response among asthmatic children from urban and rural areas living within close proximity. METHODS: In all, 448 asthmatic children from urban (363) and rural (85) areas were studied. The study group consisted of 234 9-year-olds and 214 12-year-olds. A health questionnaire was completed on each child who subsequently underwent allergic skin prick tests (SPTs). RESULTS: There was significantly more positive SPT response to house-dust mite, mold, cat, and cypress among asthmatic children from urban areas compared with children living in rural areas: 58.3% versus 37.6%, 46.1% versus 31.8%, 17.45 versus 5.9%, and 26.2% versus 15.3%, respectively. Positive SPT for indoor allergens were significantly greater among asthmatic urban residents than asthmatic rural residents: 63.3% versus 45.5%, respectively (P < 0.02). Positive SPT response to all the allergens checked was higher among the 12-year-old age group when compared with the 9-year-olds, 34.6% versus 22.7%, respectively (P = 0.05). CONCLUSIONS: Allergic response measured by SPT is significantly more common among asthmatic children from urban areas as opposed to rural, even though both areas are within small distance of one another. Further, asthmatic children living in urban areas demonstrated more allergic response to both indoor and outdoor allergens. The allergic response tends to increase with increased age in both urban and rural asthmatic children.  相似文献   
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CCR5Delta32 is a deletion mutation in the chemokine receptor CCR5. Liver inflammatory activity was found to be significantly reduced (P = 0.005) in Jewish Israeli patients infected with the hepatitis C virus (HCV) carrying the CCR5Delta32 allele. The CCR5Delta32 allele does not alter susceptibility to HCV infection; however, it may play a role in the progression and outcome of the disease.  相似文献   
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PURPOSE: Augmentation of the maxillary sinus floor is a well-documented technique and is generally accepted as a pure implantology procedure to facilitate placement of dental implants in the posterior atrophic maxilla. The objective of this report was to evaluate the significance of the sinus membrane perforations on the incidence, complications, and success rate of this procedure. PATIENTS AND METHODS: Patients who received sinus floor augmentation and simultaneous placement of dental implant were included in this study. Subgroup I consisted of patients who had their sinus membrane perforated and repaired during the procedure with resorbable membrane. Subgroup II consisted of patients whose Schneiderian membrane was not perforated during the procedure. The patients were followed between 1 to 4 years after augmentation. RESULTS: All perforations were classified as class II or III. The success rate of the implants in the perforation group was 94.4%, and that for the nonperforation group was 93.9%. The difference between the 2 study groups was statistically not significant. A significant statistical correlation was found between the residual ridge height and the membrane perforation (P < .01). CONCLUSIONS: Mainly due to technical difficulties, maxillary sinus membrane perforation occurs more frequently with a small height of residual alveolar bone. In this study, no statistical difference was observed in the success rate of the immediate implants placed with sinus bone grafting in patients whose membrane was perforated versus those patients in whom an intact membrane was maintained.  相似文献   
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BACKGROUND: Omeprazole is an inhibitor of the parietal cell enzyme H+/K+ adenosine triphosphatase. Immediate-type hypersensitivity reactions, such as urticaria, angioedema, and hypotension, induced by omeprazole and other proton pump inhibitors are rare. OBJECTIVES: To confirm the immediate-type mechanism of recurrent anaphylactic reactions to the repeated administration of omeprazole using skin testing and to enable safe administration of the drug after successful oral desensitization. METHODS: Intradermal skin tests were performed with omeprazole (0.04 and 0.4 mg/mL) prepared from the oral and intravenous commercial preparations and with pantoprazole (0.02 and 0.2 mg/mL) prepared from the oral commercial preparation. Skin tests were repeated after completion of the desensitization. Oral desensitization was applied at a starting dose of 0.001 mg of omeprazole, and a full dose of 16 mg was achieved after 5.6 hours (cumulative dose of 32.6 mg). RESULTS: Intradermal skin test results were positive to omeprazole and pantoprazole at all tested concentrations. After successful desensitization, omeprazole was administered in the full dose uneventfully. The wheal size of the intradermal skin tests performed after completion of the desensitization was significantly reduced. CONCLUSION: When indicated, this newly designed desensitization protocol may be used in patients with omeprazole-induced anaphylaxis.  相似文献   
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The aim of this study was to investigate a potential technique for image-guided minimally invasive neurosurgical interventions. Focused ultrasound (FUS) delivers thermal energy without an invasive probe, penetrating the dura mater, entering through the cerebrospinal fluid (CSF) space, or harming intervening brain tissue. We applied continuous on-line monitoring by MRI to demonstrate the effect of the thermal intervention on the brain tissue. For this, seven rabbits had a part of their skull removed to create access for the FUS beam into the brain through an acoustic window of 11 mm in diameter. Dura was left intact and skin was sutured. One week later, the rabbits were sonicated for 3 seconds with 21 W acoustic power, and the FUS focus was visualized with a temperature-sensitive T1-weighted MRI pulse sequence. The tissue reaction was documented over 7 days with T2-weighted images of the brain. The initial area of the central low signal intensity in the axial plane was .4 ± .3 mm2, and for the bright hyperintensity surrounding the lesion, it was 2.3 ± .6 mm2 (n = 7). In the coronal plane, the corresponding values were .4 ± .1 mm2 and 3.4 ± .9 mm2 (n = 5). The developing brain edema culminated 48 hours later and thereafter diminished during the next 5 days. Histology revealed a central necrosis in the white matter surrounded by edematous tissue with inflammatory cells. In summary, the image-guided thermal ablation technique described here produced a relatively small lesion in the white matter at the targeted location. This was accomplished without opening the dura or the need for a stereotactical device. MRI allowed on-line monitoring of the lesion setting and the deposition of thermal energy and demonstrated the tissue damage after the thermal injury.  相似文献   
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