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941.
Y Stern M Aronson T Shpitzer O Nativ O Medalia K Segal R Feinmesser 《Canadian Metallurgical Quarterly》1995,121(9):1003-1005
OBJECTIVE: To assess the role of DNA ploidy as a predictor of radioresistance in T1 glottic carcinoma. DESIGN: Case-control study. Flow cytometric DNA ploidy measurements were performed on formalin-fixed paraffin-embedded tumor specimens from 15 patients with T1 glottic laryngeal carcinomas in whom radiotherapy had failed and from a matched group of 15 patients in whom an identical radiotherapy regimen was curative. Analysis of DNA content was performed blind to outcome of treatment. SETTING: Academic tertiary referral medical center. PARTICIPANTS: Thirty patients with clinically staged T1, N0, M0 glottic carcinoma. INTERVENTION: All patients received radiation to the larynx through opposed lateral ports at a total dose of 64 to 70 Gy. RESULTS: Ten diploid and five aneuploid histograms were found in the resistant group, and six diploid and nine aneuploid histograms were found in the radiosensitive group. This difference was not statistically significant. A trend toward a higher relapse rate after radiotherapy (62.5%) among patients with diploid tumor compared with those with aneuploid tumor (35.7%) was noted. CONCLUSIONS: DNA ploidy did not predict response to radiotherapy in patients with T1 glottic cancer, probably because of the small number of patients. A trend toward lower risk of local recurrence after radiotherapy in aneuploid tumors was noted. A larger prospective study is needed to assess the value of DNA ploidy in the treatment of early laryngeal cancer. 相似文献
942.
Mixing of ingredients is an important operation in processing of food for obtaining the better quality product. A laboratory set‐up capable of modulating both frequency and amplitude of vibration of the grain bed was used to determine the mixing indices of paddy grains under varied experimental conditions. the mixing indices of three different types of paddy grain for three different grain bed depths were determined. the parameters varied were the vibration amplitude, frequency and the mixing time, respectively from 2 to 10 mm, 10 to 50 Hz and 5 to 120 s. Three varieties of paddy (short bold, medium slender and long slender) were used in the experiments with different length‐breadth ratio (slenderness ratio, μ, of 5.77, 4.48 and 2.70). Response surface methodology was adopted to optimize the amplitude and frequency of vibration of the mixing device. the results revealed that, the optimum frequency and amplitude of vibration for the medium slender (μ= 4.48) variety of paddy were 20–22 Hz and 8–9 mm, respectively for all the three grain bed depths of 25, 12 and 6 mm. Irrespective of grain bed depth, all the three different types of paddy showed maximum mixing indices value after 1 min of mixing. Extending the mixing time did not have any effect on mixing indices. the effect of bed depth was found to be insignificant for short bold variety of paddy. 相似文献
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Summary Multicomponent intermacromolecular complexes have been prepared from some typical phenolic copolymers with a non-ionic polymer (e.g. PVP), and a polyelectrolyte (e.g. PAA). Some transition metal ions (e.g. Cu(II) and Ni (II)) have been incorporated in the complex through its unreacted co-ordinating groups. The formation of these complexes has been studied by several techniques, such as viscometry, conductometry, potentiometry, IR and UV spectrophotometry. A scheme has been presented to explain the mode of interaction of the various components. 相似文献
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The thermal expansion of a titanium modified, swelling resistant austenitic stainless steel designated as D9 is studied by measuring the lattice parameter as a function of temperature in the range 300-1300 K by high-temperature X-ray diffraction technique. The thermal expansion data thus obtained is in reasonable agreement with the typical thermal expansion values reported for similar nuclear grade austenitic stainless steels. However, at temperatures exceeding 900 K, the measured thermal expansivity exhibits a pronounced non-linear increase due partly to the precipitation of complex carbide and intermetallic phases. The high-temperature thermal expansion data obtained in the present study are augmented by modelling the low-temperature thermal expansion behaviour by Grüneisen formalism. 相似文献
949.
The virtual path concept has several valuable features to construct an economical and efficient asynchronous transfer mode (ATM) network. One of them is bandwidth control which affords transmission efficiency improvement through statistical sharing of capacity. An effective bandwidth control algorithm and its calculated performance are described. Network performance with the algorithm is evaluated, and the bandwidth control is shown to successfully improve network transmission efficiency with only a slight increase in processing load compared to the fixed bandwidth scheme. A method is also proposed to equalize call loss probability for each virtual path. The effectiveness of the method is demonstrated by analysis 相似文献
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