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11.
Powders of uncoated disodium fluorescein (DF) and DF coated with various amounts of lauric or capric acids were generated as aerosols in an environment of controlled temperature and relative humidity. The particle size and distribution of these powders were characterized using a cascade impactor and a computerized data inversion method of analysis. Disodium fluorescein exhibited a hygroscopic growth ratio of 1.5 at a relative humidity of 97%. This growth was reduced to 1.3 by coating with 0.15 g of lauric acid or 0.8 g of capric acid per gram of DF, and was eliminated with 0.2 g of lauric acid or 0.18 g of capric acid per gram of DF. The reduction in hygroscopic growth probably reflects an inhibition of the growth rate. In the time following generation and prior to deposition in the collection device, approximately 40 s, the coated aerosol powders do not seem to reach their equilibrium droplet diameter. These studies indicate that these combinations of DF and fatty acid would result in larger equilibrium droplet diameters than that of the dye alone. 相似文献
12.
Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
13.
Instrument development: cardiac diet and exercise self-efficacy. 总被引:3,自引:0,他引:3
Self-efficacy has been documented as a strong predictor of health behaviors. Unfortunately, availability of reliable and valid measures of self-efficacy for a range of health behaviors is still limited. This study validated two measures of cardiac risk factor self-efficacy: the Cardiac Diet Self-Efficacy Instrument (CDSEI) and the Cardiac Exercise Self-Efficacy Instrument (CESEI). A sample of 370 cardiac rehabilitation participants provided data for principal factor analyses showing the unidimensionality of each instrument. Known groups construct validity was supported by a comparison of CDSEI and CESEI scores for cardiac rehabilitation participants and marathon runners. The value of CDSEI and CESEI scores in predicting subsequent exercise and diet performance was demonstrated with a third group of cardiac rehabilitation participants. Stability and internal consistency estimates in the .80s and .90s, respectively, support the scales' reliabilities. 相似文献
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J.P. Neoptolemos M. G.T. Raraty P. Ghaneh H. Hickey D.D. Stocken J. A. Dunn H. Friess M.W. Büchler 《Der Chirurg》2003,74(3):191-201
Recent advances have been made in the treatment of pancreas cancer. Specialized pancreas centres have reported an increasing rate of resections with reduced postoperative mortality. On account of the highly aggressive nature of pancreas cancer, there is a great challenge in identifying effective therapy concepts for advanced stages of the cancer as well as for the development of resection-associated measures. As large-scale, randomised, controlled studies are lacking, the additive therapy concepts after resection do not have a sufficiently scientific basis. The ESPAC-1 study, which included 600 patients, surpassed all previous studies on adjuvant therapy for pancreas cancer. This study has shown,for example, that the most promising adjuvant chemotherapy with 5-fluorouracil and folic acid leads to an equal if not better result than the multimodal regimen. This regimen can be superseded with the use of Gemcitabine, which will be evaluated in the ESPAC-3 study that includes 990 patients from various European countries including Germany, as well as from Canada and Australia. Participation in the large, phase-3 study therefore plays a key role in the continued development of the management of pancreas cancer. 相似文献
17.
M. O’Mahony R. Conroy E. Shelley N. Hickey A. Radic 《Irish journal of medical science》1991,160(9):17-21
A myocardial infarction and stroke register was established in January 1987 as part of the evaluation of the Kilkenny Health
Project This is a community programme which aims to reduce risk factors for coronary heart disease. The register records acute
myocardial infarction and stroke in residents of County Kilkenny and of the reference county. This will provide accurate estimates
of the incidence of these diseases and of trends over time.
Methods used comply with the protocol in use by the WHO MONICA Project. This will allow comparison of the incidence of coronary
heart disease and stroke in this register with that in other MONICA locations, including that in Belfast, Northern Ireland. 相似文献
18.
Pulmonary artery sling with tracheal stenosis is a difficult management problem. We describe the use of cardiopulmonary bypass as a method to facilitate one-stage repair. 相似文献
19.
The 16-kDa α-crystallin (Acr) protein of Mycobacterium tuberculosis is required for growth in macrophages
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