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In a paired-comparison study, 21 patients suffering from atopic dermatitis were treated with fluorescent tubes radiating mainly ultraviolet A (UVA) on one half of the body and with tubes radiating mainly UVB on the other. Treatment was given three times a week for up to 8 weeks. Eight variables reflecting disease status were recorded and the sum of these comprised the total score. The total score and the overall evaluation score were better with UVA therapy (P less than 0.02 and P = 0.01, respectively). No statistically significant difference for the pruritus score was found. The reduction in extent of dermatitis, seen with both therapies, was more pronounced with UVA (P less than 0.05). Differences in the healing score were not statistically significant. Treatment with UVA resulted in healing or considerable improvement in 15 patients and 13 patients showed improvement when treated with UVB. A better result was found with UVA in 10 subjects and with UVB in two subjects. Equal results occurred with both UVA and UVB in nine of the patients although most preferred UVA treatment.  相似文献   
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The efficiency of the Racal Airstream helmet respirator in improving peak expiratory flow rates (PEFR) and symptoms (dyspnea, wheezing, and cough) in aluminum potroom workers with respiratory complaints was assessed in 19 workers. Peak expiratory flow readings and symptom recording from a 2-week working period with use of the respirator were compared with a period when the 3M 9906 disposable mask was used. The study was designed as a randomized, parallel, cross-over study with five or six daily measurements of PEFR and daily symptom recording. A significant number of workers (15) had a higher mean peak flow in the helmet period than in the nonhelmet period (p less than 0.01); symptoms did not improve significantly in the helmet period. Objective evidence of respiratory protection was observed for the group of workers as a whole, but the effect on symptoms as well as individual effect on peak flow was minor in the majority of the workers.  相似文献   
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A microfluorometric method was used to determine the nuclear DNA content in the nasopharyngeal carcinomas (NPC) of 25 patients treated before 1983. Eleven patients are still alive with no evidence of disease (NED), while the rest died of their disease (DOD). All of the patients received a cycle of radiotherapy, while some also received chemotherapy or neck dissections. The neoplastic cells studied were taken from the original biopsy blocks, deparaffinized, isolated by enzymatic treatment and mechanical fragmentation, and then Feulgen-stained. The cytofluorometric measurement was carried out by a microphotometer equipped for fluorescence excitation and connected to a computer. This method allowed us to construct a histogram of the DNA content in the neoplastic cells. Different neoplastic classes were identified and represent the heteroclonality of the tumor, which can be expressed by the heteroclonality index (HCT). From the collected data it appears that the NED patients all had a low HTC (less than 1) and only 7 of the DOD patients had low HTCs (less than 1). Six of the DOD patients with a low HTC were in advanced stages of their tumor at the time of diagnosis, while the remaining patient did not complete his treatment. Our results show that the DNA analysis of the NPC cell population may offer a useful tool in predicting the biological behavior of this tumor and also improving its treatment.  相似文献   
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