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81.
Mapping therapeutic response in a patient with malignant glioma 总被引:1,自引:0,他引:1
Haney SM Thompson PM Cloughesy TF Alger JR Frew AJ Torres-Trejo A Mazziotta JC Toga AW 《Journal of computer assisted tomography》2001,25(4):529-536
Short-interval scanning of patients offers a detailed understanding of the natural progression of tumor tissue, as revealed through imaging markers such as contrast enhancement and edema, prior to therapy. Following treatment, short-interval scanning can also provide evidence of attenuation of growth rates. We present a longitudinal imaging study of a patient with glioblastoma multiforme (GBM) scanned 15 times in 104 days on a 3 T MR scanner. Images were analyzed independently by two automated algorithms capable of creating detailed maps of tumor changes as well as volumetric analysis. The algorithms, a nearest-neighbor-based tissue segmentation and a surface-modeling algorithm, tracked the patient's response to temozolomide, showing an attenuation of growth. The need for surrogate imaging end-points, of which growth rates are an example, is discussed. Further, the strengths of these algorithms, the insight gained by short-interval scanning, and the need for a better understanding of imaging markers are also described. 相似文献
82.
JW Gregory SA Greene RT Jung CM Scrimgeour MJ Rennie 《Archives of disease in childhood》1993,68(2):205-209
Fourteen children receiving one year of recombinant human growth hormone (rhGH) treatment underwent measurement of serial changes in body composition (measured by skinfold thickness, bioelectrical impedance, and H2(18)O dilution), resting energy expenditure (REE, estimated by ventilated hood indirect calorimetry), and total free living daily energy expenditure (TEE, measured by the doubly labelled water technique). Mean height velocity increased from 4.9 to 8.6 cm/year after six months of treatment. Fat free mass (FFM) increased more during the first six weeks (24.4 g/day) than from six to 26 weeks of treatment (6.8 g/day); fat mass decreased by 7.2 g/day and 1.1 g/day respectively. The six week increase in REE (kJ/day) was maintained after six months of treatment, though expressed per kilogram FFM (kJ/kgFFM/day), returned to pretreatment values by three months. Height velocity increases at six months correlated with six week changes in fat mass measured by skinfold thickness and REE, though use of this relationship to predict growth response in individuals is limited by the wide 95% prediction intervals. No significant changes in growth, body composition, or energy expenditure were observed between six and 12 months of treatment, in either patients who had initially responded well to treatment or those who were poor initial responders to treatment and who had their dose of rhGH doubled after six months. 相似文献
83.
84.
Age-related postural deficits elicit compensatory mechanisms such as ankle dorsiflexion in the elderly. To gain further insight into this problem, the ability to match an ankle angle during quiet stance was studied in 12 elderly and 12 young subjects. Following an initial single limb angular perturbation presented in the ±4° range, a subject had to return a tilt platform to level, as determined by the nonperturbed limb. Elderly subjects exhibited significant positive (0.9°) over-shoot of the level position, in contrast to young subjects who matched ankle angle with a mean error of −0.1°. The elderly group also exhibited an increase in positioning error for angular displacements in the range between −1 and +1°. The results document age-related postural changes in ankle positioning which might affect postural stability in older adults. 相似文献
85.
Multiple myeloma: evaluation by CT 总被引:3,自引:0,他引:3
Although patients who have multiple myeloma usually have straightforward clinical symptoms and corroborative radiographs, in some instances, these patients will present atypically, with symptoms suggesting active disease but radiographs that are normal or nonspecific. We reviewed the records of 32 patients who had documented multiple myeloma and had undergone CT examinations, assessing the value of those examinations. Although CT is not indicated in all patients who have multiple myeloma, it is especially useful in patients who have bone pain and normal or nonspecific radiographs. CT provided confirmatory information in all cases in which lesions were seen on radiographs. CT also frequently demonstrated a greater extent of disease than could be appreciated on the radiographs. 相似文献
86.
87.
Insufficiency fractures in the supraacetabular region were identified in five women, aged 55-83 years. Factors contributing to the diminished resistance of their bones included postmenopausal osteoporosis, steroid therapy, radiation therapy, and rheumatoid arthritis. The supraacetabular fractures were seen on routine radiographs as hazy bands of sclerosis located immediately above and parallel to the acetabular roof. All five patients had additional fractures in the spine or pelvis. Supraacetabular insufficiency fractures may be an unsuspected cause of hip pain, especially in older women. 相似文献
88.
Contrary to previous reports, we have obtained no evidence that 4a and 4b antisera specifically inhibit C3 rosette formation by human lymphocytes. Pretreatment of lymphocytes with various whole 4a and 4b antisera resulted in partial inhibition which was often nonsepcific. Ultracentrifugation of the sera to remove immune complexes removed C3 rosette inhibitory activity although specific cytotoxic activity remained. It is probable that immune complexes in antisera will have fixed C3 which will have been converted to C3d and so be able to block the C3d receptor. This is the receptor mainly measured in these and in the previous experiments. 相似文献
89.
90.
Two methods of mass population screening for colorectal cancer - faecal occult blood testing and sigmoidoscopy - have been the subject of randomized controlled trials in the UK. A national screening programme is currently under consideration and the choice of screening method remains open. To be successful, a programme will require high levels of uptake, and uptake is likely to depend upon subjects' attitudes towards the screening method introduced. Although a preferred screening method has already been identified from a questionnaire survey, we undertook a further interview study (n = 106), with a view to comparing the results of two different approaches to eliciting public preferences. In comparison with the questionnaire study, a higher proportion of interview subjects stated a preference. Interview subjects were generally more favourably disposed towards sigmoidoscopy, excepting those with previous experience. Compared with the questionnaire survey, the interviews provided richer information on the reasons for preferences offered. Individual preferences were evidently subjective and dependant on attitudes towards a variety of method characteristics, such as discomfort, convenience and perceived sophistication. Characteristics such as age and low income, which had predicted preferences in the questionnaire study, predicted preferences in the interview study also. The difference between the results obtained by the different elicitation techniques can be explained in terms of the differential provision of information and sample selection. Conclusions made about public preferences are likely to depend on the technique employed in eliciting them. 相似文献