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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A. Jaén J. Sunyer X. Basagaña S. Chinn† J. P. Zock J. M. Antó‡ P. Burney† 《Clinical and experimental allergy》2002,32(12):1713-1719
BACKGROUND: The role of atopy in the evolution to chronic obstructive disease remains controversial. AIM: We aimed to assess the association between individual sensitization to common allergens and lung function. METHOD: We analysed data from 12,687 subjects aged 20 to 44 years, from 34 centres in 15 countries participating in the European Community Respiratory Health Survey (ECRHS). Participants performed a blood test, lung function test, methacholine challenge, and answered an administered questionnaire. The relationships between specific IgE, FEV1 and FEV1/FVC ratio were assessed for each study centre stratified by sex, followed by random effects meta-analysis. RESULTS: Asthmatics sensitized to house dust mite had a lower FEV1 (-119 mL in women and -112 mL in men) and FEV1/FVC ratio (-1.95%, and -2.48%) than asthmatics without sensitization. Asthmatics sensitized to cat had a lower FEV1 (statistically significant for women only) and a lower FEV1/FVC ratio. Asthmatic women sensitized to grass had a lower FEV1 and a lower ratio, and those sensitized to Cladosporium had a lower FEV1. A weak association was found with sensitization to cat and to Cladosporium among non-asthmatic women, which disappeared after adjusting for BHR. CONCLUSION: We conclude that atopy was related to a lower lung function, which was only apparent among asthmatics. This relationship was explained by specific sensitization to cat and to house dust mite, the latter being homogeneous across areas. 相似文献
992.
993.
The triphalangeal thumb-brachyectrodactyly syndrome is a very rare autosomal dominant disorder of unknown etiology characterized by an unusual pattern of limb malformations: triphalangeal thumbs and brachyectrodactyly in the hands, and ectrodactyly in the feet. In a previous report, we described the clinical and radiographical features of three related subjects with the disease and suggest that due to the unusual combination of limb defects and to its phenotypic similarity with the limb malformative pattern induced by disrupting the Hoxd13 gene in mouse, the triphalangeal thumb-brachyectrodactyly syndrome might be caused by mutations in a HOX gene. After sequencing the entire coding region of HOXD13 and the highly conserved homeodomain encoding region of HOXA13, we do not detect any deleterious mutation in any of the patients excluding that alterations at these sequences are responsible for the disease. Mutations in regulatory regions of these genes or in other genes involved in limb development might be responsible for the disease. 相似文献
994.
995.
The authors report the association of erythroleukemia (FAB M6) and fetal hemoglobin (HbF) level of at least 65% after therapy for ovarian carcinoma. The patient's erythrocytes had many signs of reversion to fetal-like erythropoiesis including: elevated HbF with a fetal G gamma/A gamma (gly/ala) of 3/1, low hemoglobin A2 (HbA2), macrocytosis, and increased i antigen. These data and data from other case reports suggest that elevation of HbF to greater than 25% with reversion to fetal-like erythropoiesis is useful in differentiating erythroleukemia from other preleukemic disorders. 相似文献
996.
R J Elwood P J Hildebrand J W Dundee P S Collier 《British journal of clinical pharmacology》1983,15(6):743-745
In a randomised crossover study in volunteers plasma midazolam levels were estimated for 24 h following 15 mg by mouth, either preceded by no medication or following 24 h therapy with ranitidine. Administration of the H2-receptor blocker significantly increased bioavailability of the benzodiazepine and resulted in higher plasma levels for the first 6 h after taking midazolam. This was accompanied by a greater soporific effect. 相似文献
997.
S. Whitehead 《Postgraduate medical journal》1980,56(651):69-70
The development of identically sited carcinomas of the colon in monozygotic twins is described. Presentation occurred with 2 years of each other. They are discussed in the context of the cancer-family syndrome. 相似文献
998.
999.
S Amartur Z P Liang F Boada E M Haacke 《Journal of magnetic resonance imaging : JMRI》1991,1(6):721-724
The authors present an improvement to a sigma-filter extrapolation method for the reconstruction of magnetic resonance (MR) images from symmetric discrete Fourier data. By making use of the phase information in the image data, the proposed method can overcome the data inconsistency problem of the original method for handling MR image data with large phase variations, such as those obtained in gradient-echo pulse sequences. Reconstruction results show that its performance is comparable with that of the modified complex sigma-filter method proposed previously to handle the inconsistency problem. However, the new approach has the advantage of reducing computation time by a factor of two with use of a sigma filter applied to real instead of complex images. It is expected that this method will be more practical for use in clinical MR imaging systems. 相似文献
1000.
K Mahmood M N Chowdhury E A Ayoola I A Mofleh R S Rashed F Z Faleh 《Tropical gastroenterology》1991,12(4):188-191
Seventy seven antral biopsies were collected from patients attending endoscopy clinic at King Khalid University Hospital, Riyadh, Saudi Arabia during a period of six months between December 1988 to May 1989. Of these 69 (89.6%) showed chronic gastritis as well as Helicobacter-like organisms (HLOs) in the biopsy specimens while 63 (81.8%) of biopsies grew Helicobacter pylori on culture. These findings indicate a good correlation between the histological diagnosis of chronic gastritis and isolation of H. pylori on culture. 相似文献