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21.
Multimodality medical imaging enables measurement of the three-dimensional spatial distribution of a radiolabeled aerosol within the lung. Using a conceptual spatial morphological model these data may be transformed to provide information on deposition per airway generation. This methodology has been used to study the intrapulmonary deposition patterns of two formulations of a metered dose inhaler and two nebulizers in control subjects. The nebulizer study has also been stimulated using a computer model of deposition. The comparison between derived experimental results and those from computer modeling shows areas of agreement, although there are also areas of discrepancy. The new methodology has considerable potential value in the fields of inhalation therapy and deposition modeling, although more detailed validation is still required.  相似文献   
22.
As more patients survive cancer, and as more sophisticated multidrug antineoplastic protocols are developed, the chances of an anesthesiologist's coming into contact with patients who have been treated with such protocols are increasing. The anesthesiologist who must administer anesthesia to a patient who has had chemotherapy must be cognizant of the particular antineoplastic agents that have the potential for producing occult pulmonary dysfunction. Anesthetic management of these cases must be carefully planned and titrated to prevent further lung injury.  相似文献   
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Three sheets of 10 surface area determinations were completed by 10 subjects using a nomogram and a formula. The formula was faster to calculate, 4.27 v 7.6 minutes for each sheet, and resulted in fewer serious errors (three v 30 errors).  相似文献   
25.
BACKGROUND AND PURPOSE: Odontoma is the most common odontogenic tumor. It includes 2 types, the compound and complex odontomas. There has not been a series study of the clinical and histologic features of odontomas from Taiwan. This study evaluated the clinicopathologic features of odontoma in Taiwanese. METHODS: Cases of odontoma treated from 1998 to 2002 identified from medical records were included. The microscopic features, radiographic features, and clinical history of the patients were reviewed and analyzed. RESULTS: A total of 81 odontomas in 81 patients (36 males and 45 females) were included. There were 62 compound and 19 complex odontomas. The mean age of the patients was 18 years with the majority of odontomas occurring in the first (32%) and second decade (38%) of life. Odontomas had a marked predilection for the maxilla (70%) and for the anterior region of the jaw (83%), particularly for the anterior maxilla (62%). Sixty four (79%) of the 81 odontomas were associated with 80 impacted teeth, including 71 permanent teeth, 2 deciduous teeth, and 7 supernumerary teeth. Of the 71 impacted permanent teeth, the maxillary central incisor (27%) was most commonly affected, followed by the maxillary canine (26%) and mandibular canine (24%). Histologic examination revealed enamel matrix in 90%, dentin in 100%, cementum in 88%, pulp tissue in 96%, fibrous capsule in 93%, ghost cells in 83%, reduced enamel epithelium in 86%, and nests of odontogenic epithelium in 58% of odontomas. Dentigerous cyst was associated with 9% of odontomas. CONCLUSIONS: In this series, odontomas occurred most often in the first and second decade of life. Although complex odontomas are usually found in the posterior jaw, in this Taiwanese series they were most commonly found in the anterior maxilla. Odontoma is frequently associated with an impacted tooth and occasionally with a dentigerous cyst. No recurrence of odontomas was found after surgical excision with follow-up of 1 to 15 years.  相似文献   
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To investigate the involvement of adrenergic mechanisms in the development of obesity, hyperglycaemia and hyperinsulinaemia in Aston ob/ob mice, the sympathomimetic agent ephedrine (12 mg/kg/day) and the predominantly beta 1-adrenergic antagonist atenolol (12 mg/kg/day) were administered alone and in combination to weanling ob/ob mice for 40 days. Excessive weight gain in ob/ob mice was reduced (15-20%) by ephedrine, exacerbated (8-10%) by atenolol, but not significantly altered by a combination of these agents. The effects of ephedrine and atenolol were lost rapidly (within 5 days) when these agents were withdrawn. Ephedrine slightly reduced the hyperphagia in ob/ob mice, and food intake was transiently increased above that of untreated ob/ob mice when this agent was withdrawn. The development of basal hyperglycaemia and hyperinsulinaemia was not significantly altered by any of the treatments studied. None of the treatments significantly altered body weight, food intake, plasma glucose or plasma insulin concentrations in lean (+/+) mice. The results indicate that a defective adrenergic mechanism involving beta 1-adrenergic receptors contributes to the development of obesity in ob/ob mice.  相似文献   
28.
A 56-y-old female cardiac transplant patient treated with cyclosporine and prednisone noted the onset of three nontender red nodules on the legs and arms after gardening. Biopsy of all lesions revealed inflammatory cells and hyphal elements in the dermis. The dematiaceous fungus cultured from biopsy tissue was a pycnidial-forming organism of the genus Pleurophoma. The lesions responded to the topical application of miconazole.  相似文献   
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The susceptibility of urinary tract Escherichia coli isolates to cotrimoxazole, sulphonamide, trimethoprim, and ampicillin was monitored over an 11-year period. A trend in increasing resistance to cotrimoxazole and trimethoprim was observed, but there was no comparable alteration in sulphonamide resistance. Ampicillin resistance was high at the beginning of the survey period and continued to rise.  相似文献   
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