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61.
SB Balmukhanov SV Kozhanova NA Smagulova IuSh Kaliev IuSh Kosaev 《Canadian Metallurgical Quarterly》1976,22(7):14-20
The authors have studied phytohemagglutinin stimulation of DNA synthesis in leucocytes cultures of the peripheral blood in patients with some malignant osteoplasms and benign tumors, and the influence of plasma factors on this process, as well. In most cases, lymphocytes of patients with malignant tumors were shown to have a considerably decreased, as compared with the control, level of blasttransformation. No such difference was found for leucocytes cultures of patients with benign tumors. 相似文献
62.
SV Likhvitski? 《Canadian Metallurgical Quarterly》1976,10(3):61-64
Examination of electrocardiograms of pilots with normal and 10% excessive weight in a moderately hypoxic atmosphere showed that changes in the pulse rate, T voltage, systolic index were less expressed in obese subjects than in normal pilots. This can be attributed to the fact that obese subjects had reduced metabolism, minute oxygen consumption and compensatory capabilities of the cardiovascular system. 相似文献
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The authors studied 41 patients with acute disorders of cerebral circulation, a focus in the right hemisphere and 14 with foci in the left hemisphere. The traits of compensatory reactions were studied according to the background and functional EEG, depending upon the severity, stage, localization and lateralization of focal vascular brain lesions. The authors indicate to a rigidity of clinical and EEG changes in patients with right hemispheric localization of the focus which is explained by the authors by disturbances of the higher cortical functions in these patients. 相似文献
66.
The object of the study was to determine whether a first-morning urine specific gravity of less than or equal to 1.015 was associated with enuresis in children 3 to 6 years old. Parents of preschool children seen at the Cleveland Clinic Foundation during a 5-month period completed a questionnaire concerning bed-wetting and voiding habits of their child and collected first-morning urine specimens for specific gravity analysis. Of 101 children, 12 had a urine specific gravity of less than or equal to 1.015 (11.9%), including seven of 73 (9.6%) nonbed-wetters, two of 19 (10.5%) bed-wetters by history (who did not wet their beds on the night of the study), and three of nine (33.3%) bed-wetters (who wet their beds on the night of the study). The 73 nonbed-wetters (72.3%) had a mean (+/- standard deviation) urine specific gravity of 1.022 (+/- 0.006); 19 bed-wetters by history (18.9%) had a mean urine specific gravity of 1.024 (+/- 0.006); and nine bed-wetters (8.9%) had a mean urine specific gravity of 1.019 (+/- 0.005). The groups' mean urine specific gravities were not significantly different (p = 0.10) and the enuretic children were not more likely to have first-morning-void urine specific gravity of less than or equal to 1.015 than nonenuretic children (p = 0.14). Enuretic children who wet their beds on the night of the study had lower mean urine specific gravity than nonbed-wetters although the difference was not significant. Therefore, we do not recommend routine use of first warning void urine specific gravity analysis for predicting presence or absence of enuresis. 相似文献
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This paper presents a M6800 microprocessor based hardware monitor for measuring certain selected parameters of the EC-1030 computer system. The motivation for this work was to get an insight into the operation of the system under the present work load and use these results towards improvement and design studies. The three main classes of quantitative indices of computer system performance/productivity, responsiveness and use have been measured using hardware and software tools. This paper describes the hardware monitor design and discusses the measurements made. 相似文献
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MM Goodsitt HP Chan B Liu SV Guru AR Morton S Keshavmurthy N Petrick 《Canadian Metallurgical Quarterly》1998,25(6):937-948
We are developing an external filter method for equalizing the x-ray exposure in mammography. Each filter is specially designed to match the shape of the compressed breast border and to preferentially attenuate the x-ray beam in the peripheral region of the breast. To be practical, this method should require the use of only a limited number of custom built filters. It is hypothesized that this would be possible if compressed breasts can be classified into a finite number of shapes. A study was performed to determine the number of shapes. Based on the parabolic appearance of the outer borders of compressed breasts in mammograms, the borders were fit with the polynomial equations y = ax2 + bx3 and y = ax2 + bx3 + cx4. The goodness-of-fit of these equations was compared. The a,b and a,b,c coefficients were employed in a K-Means clustering procedure to classify 470 CC-view and 484 MLO-view borders into 2-10 clusters. The mean coefficients of the borders within a given cluster defined the "filter" shape, and the individual borders were translated and rotated to best match that filter shape. The average rms differences between the individual borders and the "filter" were computed as were the standard deviations of those differences. The optimally shifted and rotated borders were refit with the above polynomial equations, and plotted for visual evaluation of clustering success. Both polynomial fits were adequate with rms errors of about 2 mm for the 2-coefficient equation, and about 1 mm for the 3-coefficient equation. Although the fits to the original borders were superior for the 3-coefficient equation, the matches to the "filter" borders determined by clustering were not significantly improved. A variety of modified clustering methods were developed and utilized, but none produced major improvements in clustering. Results indicate that 3 or 4 filter shapes may be adequate for each mammographic projection (CC- and MLO-view). To account for the wide variations in exposures observed at the peripheral regions of breasts classified to be of a particular shape, it may be necessary to employ different filters for thin, medium and thick breasts. Even with this added requirement, it should be possible to use a small number of filters as desired. 相似文献