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NN Nawar 《Canadian Metallurgical Quarterly》1980,108(1):30-33
A pericentric inversion of an X chromosome [46,X,inv(X)(p11q28] with no detectable deletions was ascertained by amniocentesis for prenatal diagnosis in a 42-year-old woman. No defintive counsel could be offered as such an inversion had not been previously reported. At 1 year, the infant appears normal. These data and the review of other recently published karyotypes suggest an absence of a somatic position effect in the human X chromosome and possible biases of ascertainment or possible alternative karyotypic interpretations of some previously reported inv(X) cases. 相似文献
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Albanese Massimiliano Chianese Angelo Moscato Vincenzo Sansone Lucio 《Multimedia Tools and Applications》2004,24(3):253-272
The first step in a video indexing process is the segmentation of videos into meaningful parts called shots. In this paper we present a formal model of the video shot segmentation process. Starting from a mathematical characterization of the most common transition effects, a video segmentation algorithm capable to detect both abrupt and gradual transitions is proposed. The proposed algorithm is based on the computation of an arbitrary similarity measure between consecutive frames of a video. The algorithm has been tested adopting a similarity metric based on the Animate Vision theory and results have been reported. 相似文献
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DH Kang CL Coe DO McCarthy NN Jarjour EA Kelly RR Rodriguez WW Busse 《Canadian Metallurgical Quarterly》1997,17(8):481-487
T cell cytokines play an important role in mediating airway inflammation in asthma. The predominance of a Th2 cytokine profile, particularly interleukin (IL)-4 and IL-5, is associated with the pathogenesis and course of asthma. The aim of this study was to test the hypothesis that a stressful life event alters the pattern of cytokine release in asthmatic individuals. Thirteen healthy controls and 21 asthmatic adolescents gave blood samples three times over a semester: midsemester, during the week of final examinations, and 2-3 weeks after examinations. Interferon-gamma (IFN-gamma), IL-2, IL-4, and IL-5 were measured from supernatants of cells stimulated with PHA/PMA for 24 h. Cells from asthmatic subjects released significantly more IL-5 during the examination and postexamination periods, whereas cells from healthy controls released significantly more IL-2 during the midsemester and examination periods, thereby indicating a bias for a Th2-like pattern in asthmatics and a Th1-like pattern in healthy controls. IL-4 and IL-5 production showed a marked decrease during and after examinations in healthy controls, whereas this decline was absent in asthmatics. The ratios of IFN-gamma:IL-4 and IFN-gamma:IL-5 also revealed significant changes in the profile of cytokine release across the semester. These results indicate differential cytokine responses in asthmatics that may become pronounced during periods of cellular activation. 相似文献
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A Daniele A Albanese G Gainotti B Gregori P Bartolomeo 《Canadian Metallurgical Quarterly》1997,349(9060):1222-1223
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