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101.
102.
PURPOSE: We evaluated anthropometric and performance measures that best predict bone mineral density (BMD) and bone mineral content (BMC) in 54 adolescent girls (14.6 +/- 0.5 yr; 22.7 +/- 14.0 months past menarche). METHODS: Whole body, femoral neck, greater trochanter, lumbar spine (L2-L4), and mid-femoral shaft BMD and BMC, and whole body bone-free lean mass and fat mass were assessed using DXA (Hologic QDR 1000/W). Knee extensor strength and leg power were assessed by isokinetic dynamometry and the Wingate Anaerobic Power Test, respectively. RESULTS: Whole body lean mass was correlated with BMD at all bone sites (r = 0.45-0.77; P < 0.001) and was more highly correlated with bone at all sites than was body weight. Leg power was also associated with BMD at all sites (r = 0.41-0.67; P < 0.001), whereas leg strength correlated significantly with all sites (r = 0.41-0.53; P < 0.001) except the lumbar spine. Stepwise regression analyses revealed that 59% of the variance in whole body BMD was predicted by lean mass alone. No other variables, including fat mass, height, months past menarche, leg power, or leg strength, contributed additionally to the regression model. Similarly, lean mass was the only predictor of lumbar spine and femoral shaft BMD (R2 = 0.25, R2 = 0.37, respectively), while femoral neck and trochanteric BMD were best predicted by leg power (R2 = 0.38, R2 = 0.36, respectively). Similar but stronger models emerged using BMC as the outcome, with lean mass and leg power explaining the most variance in BMC values. CONCLUSION: In this group of adolescent girls, lean body mass and leg power best predicted BMC and BMD of the whole body, lumbar spine, femoral shaft, and hip, which may suggest an important role for muscle mass development during growth to maximize peak bone density. 相似文献
103.
104.
PB Greer K Dahl MA Ebert M White C Wratten P Ostwald P Pichler JW Denham 《Journal of Medical Imaging and Radiation Oncology》2008,52(5):517-524
The aims of this study were to investigate whether intrafraction prostate motion can affect the accuracy of online prostate positioning using implanted fiducial markers and to determine the effect of prostate rotations on the accuracy of the software‐predicted set‐up correction shifts. Eleven patients were treated with implanted prostate fiducial markers and online set‐up corrections. Orthogonal electronic portal images were acquired to determine couch shifts before treatment. Verification images were also acquired during treatment to assess whether intrafraction motion had occurred. A limitation of the online image registration software is that it does not allow for in‐plane prostate rotations (evident on lateral portal images) when aligning marker positions. The accuracy of couch shifts was assessed by repeating the registration measurements with separate software that incorporates full in‐plane prostate rotations. Additional treatment time required for online positioning was also measured. For the patient group, the overall postalignment systematic prostate errors were less than 1.5 mm (1 standard deviation) in all directions (range 0.2–3.9 mm). The random prostate errors ranged from 0.8 to 3.3 mm (1 standard deviation). One patient exhibited intrafraction prostate motion, resulting in a postalignment prostate set‐up error of more than 10 mm for one fraction. In 14 of 35 fractions, the postalignment prostate set‐up error was greater than 5 mm in the anterior–posterior direction for this patient. Maximum prostate rotations measured from the lateral images varied from 2° to 20° for the patients. The differences between set‐up shifts determined by the online software without in‐plane rotations to align markers, and with rotations applied, was less than 1 mm (root mean square), with a maximum difference of 4.1 mm. Intrafraction prostate motion was found to reduce the effectiveness of the online set‐up for one of the patients. A larger study is required to determine the magnitude of this problem for the patient population. The inability in the current software to incorporate in‐plane prostate rotations is a limitation that should not introduce large errors, provided that the treatment isocentre is positioned near the centre of the prostate. 相似文献
105.
106.
G B Snow 《Acta oto-laryngologica》1989,107(5-6):352-356
Surgery and radiotherapy are still the best local and regional treatments for the majority of head and neck cancer patients, each alone having an impressive cure rate. However, it appears that surgery and radiotherapy have reached their upper limits. To improve the results obtained by surgery and radiotherapy, combined approaches with chemotherapy or immunotherapy must be further explored. Prospective randomized trials are essential for the evaluation of the efficacy of such multimodality treatments. Although there is an increasing commitment to this type of clinical research amongst otolaryngologists/head and neck surgeons, we still lag considerably behind other surgical and medical disciplines. Broad peer support is the conditio sine qua non that prospective randomized studies will be successfully conducted in head and neck oncology. Such studies, irrespective of their outcome in terms of which treatment is best, will provide data on important issues like that of failure sites. Accurate evaluation of the magnitude of the failure problem at respectively the local, the regional and the distant level are essential for estimating the potential for gains and establishing priorities for clinical research. 相似文献
107.
D J Adelstein V M Sharan N J Snow S G Carter T P Horrigan J D Hines 《Medical and pediatric oncology》1989,17(1):15-19
Seven patients with locally far-advanced, inoperable, squamous cell cancer of the esophagus were given two cycles of concurrent radiation and chemotherapy. Each cycle consisted of 5-fluorouracil 1,000 mg/m2/day given as a continuous intravenous infusion over 96 hours, cisplatin 75 mg/m2 given as an intravenous bolus on day 1, and methotrexate 40 mg/m2 given as an intravenous bolus on days 8 and 15. Three thousand rads of radiation were given in 15 fractions between days 1 and 19. Six patients are evaluable for response. Symptomatic relief was obtained by all six and was complete in 4. Five patients achieved a complete response, and two remain alive and disease free. Five of the six evaluable patients survived for at least 12 months. Aggressive chemoradiotherapy may result in significant survival prolongation and symptomatic palliation in this poor-prognosis subset of patients with esophageal cancer. 相似文献
108.
It has been widely believed that, by combining the services for preventing and treating sexually transmitted infections (STI) with those for family planning (FP), STI coverage would increase and the combined service would be of higher quality and more responsive to the needs of women. So far, there is little concrete evidence that integration has had such an impact. Besides the absence of documentation, a clear definition of integration is lacking. We therefore carried out a comprehensive review of concrete experiences with integrated services, and present a summary of our findings in this article. The results indicate that the tasks of STI prevention, such as education for risk reduction and counselling, have been integrated into family planning services much more frequently than the tasks of STI diagnosis and treatment. Some STI/FP integration efforts appear to have been beneficial, for instance when the integration of STI/HIV prevention had a positive impact on client satisfaction, and on the acceptance of family planning. Less clear is whether STI prevention, when concentrated among traditional FP clients, is having a positive impact on STI risk behaviours or condom use. A few projects have reported increases in STI caseloads following integration. In some projects, FP providers were trained in STI case management, but few clients were subsequently treated. 相似文献
109.
Malignant adenolymphoma of the parotid gland: report of carcinomatous transformation 总被引:1,自引:0,他引:1
T Onder R M Tiwari I van der Waal G B Snow 《The Journal of laryngology and otology》1990,104(8):656-661
Malignant transformation of an adenolymphoma (Warthin's tumour) is a rare event. This paper presents a case of carcinoma arising in an adenolymphoma of the parotid gland. 相似文献
110.
M. W. M. van den Brekell H. V. Stele P. van der Valk I. van der Waal C. J. L. M. Meyer G. B. Snow 《European archives of oto-rhino-laryngology》1992,249(6):349-353
Summary The incidence of micrometastases in cervical lymph nodes from squamous cell carcinomas of the head and neck was studied using routine histopathological examination. Micrometastases were found in 66 lymph nodes in 41 of the 92 tumor-positive neck dissection specimens. The detection of these micrometastases influenced postoperative treatment in 3 of the 77 patients with neck node metastases. The value of additional sectioning for detecting micrometastases was thus assessed. Sectioning at a deeper level in 600 originally histopathologically negative lymph nodes from 64 patients revealed 7 additional micrometastases in 5 patients. Antikeratin staining with a mixture of two monoclonal antibodies (AE1 and AE3) revealed 4 micrometastases in 739 originally histopathologically negative lymph nodes in 3 of 13 patients studied. Because of the unknown prognostic significance of micrometastases and the consequent arbitrary consequences for postoperative treatment, present findings show that the extra workload of immunostaining and deeper sectioning does not warrant their routine use in clinical practise. 相似文献