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81.
82.
Ultrasonic velocity measurements through the calcaneus: Which velocity should be measured? 总被引:3,自引:0,他引:3
Dr C. G. Miller R. J. M. Herd T. Ramalingam I. Fogelman G. M. Blake 《Osteoporosis international》1993,3(1):31-35
The assessment of skeletal integrity by the measurement of ultrasonic velocity through the calcaneus has only recently become widely available and is usually made in conjunction with the measurement of broadband ultrasonic attenuation. Using data obtained with a contact ultrasonic bone analyser (CUBA) system, this report examines whether ultrasonic studies of the heel require the measurement of true velocity of sound in the calcaneus (Vbone), or whether heel velocity (Vheel, defined as the mean velocity through bone and soft tissue) or time of flight velocity (Vtof, defined as the mean velocity between the two transducers) are adequate surrogates. The populations selected for study were 15 healthy young women (group 1, mean age 26 years), 231 healthy peri- and postmenopausal women (group 2, mean age 52 years) and 33 osteoporotic women with confirmed vertebral fracture (group 3, mean age 66 years). Precision was studied by performing 10 repeated scans on the subjects in group 1 and duplicate scans on 144 women randomly selected in groups 2 and 3. Precision was expressed as the percentage coefficient of variation (CV). Both precision studies yielded similar results. The precisions (and 5% to 95% ranges) for all groups combined were: Vbone 2.71% (1465–1809 m/s); Vheel, 1.10% (1511–1646 m/s); Vtof, 0.70% (1349–1425 m/s). Although the precision data suggest Vtof should be preferred, when the range of clinical values is taken into account the smaller CV is exactly cancelled by the narrower range. To demonstrate this numerically it is proposed to introduce a new measure of precision, the standardized coefficient of variation (SCV), defined as the percentage CV divided by the percentage ratio of the range over the mean. SCV had a value of 12.7% for Vtof and 12.8% for Vbone and Vheel. For comparison a SCV of 2.2% was estimated for dual X-ray absorptiometry (DXA). Thus the measurement of ultrasonic velocity through the calcaneus compares equally in terms of CV, but not in terms of SCV. A scatter plot of Vbone against Vtof gave a significantly poorer correlation (r=0.828) than that of Vbone against Vheel (r=0.984). This latter correlation can be explained by theoretical studies demonstrating convergence of the two measurements when the velocity through the bone equals that through soft tissue (1540 m/s). Since the measurement of Vheel dispenses with the need to determine soft tissue thickness over the calcaneus, it is the optimum velocity parameter for the CUBA system. 相似文献
83.
R. J. M. Herd G. M. Blake T. Ramalingam C. G. Miller P. J. Ryan I. Fogelman 《Calcified tissue international》1993,53(3):153-157
Summary Measurements of broadband ultrasonic attenuation (BUA) and velocity of ultrasound through the heel (heel velocity, HV) were performed with a Contact Ultrasonic Bone Analyzer (CUBA-Research model) in 229 women. The subjects consisted of 16 healthy young volunteers (Group 1, mean age 26 years), 170 healthy pre- and postmenopausal women (Group 2, mean age 53 years), and 43 osteoporotic women with radiographically defined vertebral crush fracture (Group 3, mean age 66 years). Subjects in Group 1 had 10 repeated measurements in a study of short-term precision. Women in Groups 2 and 3 also had dual X-ray absorptiometry (DXA) scans to measure lumbar spine and femoral neck bone mineral density (BMD). The BUA and HV measurements for all 229 women showed a significant correlation (r = 0.75,P < 0.001). The precision study on the subjects in Group 1 gave a root mean square coefficient of variation of 6.3% for BUA and 1.04% for HV. Linear regression analysis gave the following relationship between BUA and age for the 170 normal women in Group 2: BUA = 83.6 – 0.86 (age 40) dB/MHz (r = –0.31,P < 0.001, SEE = 16.3 dB/MHz). The relationship between HV and age was as follows: HV = 1614 – 2.3 (age 40) m/s (r = –0.33,P < 0.001, SEE = 42 m/s). Multivariate regression analysis showed that in addition to age, years since the menopause was also a significant factor in determining both BUA and HV. In the first 5 years following the menopause, BUA and HV decreased by 2.2% and 0.3%/year, respectively, whereas in the next 10 years the rates of decrease fell to 0.5% and 0.03%/year. The BUA and HV measurements on the 43 osteoporotic subjects in Group 3 gave mean T-scores of –2.1 and –1.9 compared with 59 premenopausal women, and mean Z-scores of –1.3 and –0.9 compared with 26 age-matched normal women in Group 2, respectively. In comparison, the lumbar spine and femoral neck DXA measurements in the same subjects gave mean T-scores of –2.9 and –2.1 and mean Z-scores of –1.7 and –1.0, respectively. Lumbar spine BMD gave the best discrimination between women with osteoporotic vertebral fractures and normal subjects. However, the difference between the lumbar spine and BUA Z-scores was not statistically significant. Femoral neck BMD was equivalent to the ultrasound parameters in T-score and Z-score values. 相似文献
84.
85.
K. K. Ramalingam V. Venkateswaran C. Indramohan P. Thulsi Das S. M. Selvaraju N. J. Rajan 《Indian journal of otolaryngology and head and neck surgery》1983,35(1):19-20
A Case of radiation induced fibrosarcoma of the maxilla following irradiation of a nasopharyngeal carcinoma is presented. 相似文献
86.
K. K. Ramalingam A. Kamalam V. Venkateswaran N. J. Rajan S. M. Selvaraju P. Thulasi Dhas 《Indian journal of otolaryngology and head and neck surgery》1983,35(4):95-96
A rare case of Rhinoentomophthoromycosis is presented along with line of management. 相似文献
87.
88.
Xie JT Chang WT Wang CZ Mehendale SR Li J Ambihaipahar R Ambihaipahar U Fong HH Yuan CS 《The American journal of Chinese medicine》2006,34(2):279-284
We observed that curry leaf (Murraya koenigii) extract possesses the property to decrease blood cholesterol and blood glucose levels in diabetic ob/ob mice. Mice received daily intraperitoneal injections of 80 mg/kg curry leaf extract for 10 consecutive days. The extract significantly decreased blood cholesterol level from 277.6 +/- 16.6 mg/d (day 0) to 182.0 +/- 15.3 mg/d (day 10, p < 0.01 compared with the change in vehicle group). The extract also significantly decreased blood glucose level from 387.0 +/- 15.6 mg/dl (day 0) to 214.0 +/- 26.6 mg/dl (day 10, p < 0.01). In addition, body weight was reduced after extract treatment. Our data suggest that curry leaf may be proved to be of clinical importance in improving the management of high cholesterol level and type 2 diabetes. 相似文献
89.
Ramanathan RK Ramalingam S Egorin MJ Belani CP Potter DM Fakih M Jung LL Strychor S Jacobs SA Friedland DM Shin DM Chatta GS Tutchko S Zamboni WC 《Cancer chemotherapy and pharmacology》2005,55(4):354-360
Purpose Capecitabine in combination with docetaxel given every 3 weeks has shown a high degree of activity in a number of tumor types, but at the expense of significant toxicity. To improve the therapeutic index, we evaluated a weekly regimen of docetaxel in combination with capecitabine, and determined the maximum tolerated dose, toxicities and pharmacokinetics of this combination.Patients and methods Patients with advanced solid malignancies were treated with docetaxel on days 1 and 8, and capecitabine, twice daily on days 1–14, of an every-21-day cycle. Pharmacokinetics of docetaxel were assessed on days 1 and 8 of the first cycle of chemotherapy.Results Enrolled in the study were 25 patients. The most frequent toxicities were asthenia, hand-foot syndrome and mucositis. Inability to deliver at least 75% of the planned doses of both drugs during the first two cycles of chemotherapy was noted at dose levels 2, 3 and 4. Dose level 1 (docetaxel 30 mg/m2 and capecitabine 825 mg/m2 twice daily) is the recommended dose for phase II studies. Five patients experienced a partial response, and eight patients had stabilization of disease. Coadministration of capecitabine did not alter the pharmacokinetics of docetaxel.Conclusion The regimen consisting of docetaxel 30 mg/m2 (days 1, 8) and capecitabine 825 mg/m2 twice daily (days 1–14) was well tolerated. Capecitabine did not alter pharmacokinetics of docetaxel. Further testing of this regimen in tumor-specific trials, especially gastric, lung and breast cancer, is warranted.Presented at the 39th Annual Meeting of the American Society of Clinical Oncology, May 2003, Chicago, IL. 相似文献
90.
Veena V. Ramalingam Monika Mani Vijayanand C. Sundaresan Ramesh J. Karunaiya Jaiprasath Sachithanandham Rajesh Kannangai 《Clinical and Vaccine Immunology : CVI》2012,19(10):1693-1696
CD4+ T cell count estimations are subject to high variations; hence, in this study, the previous day''s tested samples were included routinely as the internal quality controls. The percentages of variation of the 2-day values were analyzed for 280 observations and the mean variation for CD4+ and CD3+ T cell counts ranged from 5.21% to 9.66%. This method is a good internal quality control (IQC) procedure for the estimation of CD3+ and CD4+ T cell counts in resource-poor settings. 相似文献