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152.
基于差别特征的神经网络人脸识别 总被引:3,自引:0,他引:3
根据视觉识别的差别特征分辨特性,该文对自联想神经网络进行了改进,提出了基于差别特征的识别方法。文中采用ORL人脸图象库进行的对比识别实验表明,改进后的差别特征神经网络对原人脸图象和加斯噪声的人脸图象,都较自联想神经网络识别高,证实了差别特征的有效性。 相似文献
153.
IeM Panasiuk LH Levkut IL Popovych OI Alieksieiev MM Kovbasniuk VP Balanovs'ky? 《Canadian Metallurgical Quarterly》1994,40(3-4):25-30
The effect of balsam "Kryms'ky?" has been studied in chronic experiments on Wistar rats. It is proved that peroral administration of balsam "Kryms'ky?" to rat for 4-7 days enhances excretion of 17-KC, static and dynamic muscular workability, resistance to hypoxia, accelerates elimination of xenobiotics, decreases stress-induced damages of the stomach mucosa, myocardium and lymphopenia. This permits considering the balsam an adaptogen and recommending it for clinical test. 相似文献
154.
LN Iashina IP Gileva AB Ryzhikov VA Poryvaeva IA Riazankin TS Bondar'' LG Ovechkina OI Riazankina EG Malygin 《Canadian Metallurgical Quarterly》1997,36(3):36-40
The role and importance of accomplished fertility compared to the total number of pregnancies is discussed from the point of view of working activities, medico-social insurance and amount of risk insurance indemnities of women during different phases of the individual reproductive cycle for the period 1985-1995 in Bulgaria. It is pointed out that the continuing unfavourable demographic tendencies are directly linked with the level of the reproductive function of women. Their individual behaviour in the accomplishment of that function is motivated mainly by changes of economic factors, optimal social insurance indemnities during different phases of the cycle, success in the control of pregnancy complications and especially increasing emotional acceptance of abortions, which sharply exceed births. 相似文献
155.
JJ Sando OI Chertihin JM Owens RH Kretsinger 《Canadian Metallurgical Quarterly》1998,273(51):34022-34027
In many lipid systems, the activity of protein kinase C (PKC) exhibits a peak followed by a decline as the mol % of one component is increased. In these systems, an increase in one lipid component is always at the expense of another or accompanied by a change in total lipid concentration. Here we report that in saturated phosphatidylserine (PS)/phosphatidylcholine (PC)/diacylglycerol (DAG) mixtures, increasing PS or DAG at the expense of PC revealed an optimal mol % PS, dependent on mol % DAG, with higher mol % PS diminishing activity. The decrease at high mol % PS is probably not attributable simply to more gel-phase lipid due to the higher melting temperature of saturated PS versus PC because a similar peak in activity occurred in unsaturated lipid systems. Increasing the total lipid concentration at suboptimal mol % PS provided the same activity as higher mol % PS at lower total lipid concentration. However, at optimal mol % PS, activity increased and then decreased as a function of total lipid concentration. PKC autophosphorylation also exhibited an optimum as a function of mol % PS, and increasing the PKC concentration increased the mol % PS at which activity decreased, both for autophosphorylation and for heterologous phosphorylation. Formation of two-dimensional crystals of PKC on lipid monolayers also exhibited a peak as a function of mol % PS, and the unit cell size of the crystals formed shifts from 50 x 50 A at low mol % PS to 75 x 75 A at higher PS. Collectively, these data suggest the existence of optimal lipid compositions for PKC activation, with increased quantity of these domains serving to dilute out enzyme-substrate aggregates and/or enzyme-enzyme aggregates on the lipid surface. 相似文献
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NMR tomography (NMRT) of the brain and NMR angiography (NMRA) of the extra- and intracranial arteries were performed on the unit Magnetom 63 SP (1.5 T) Siemens in 13 healthy controls and 87 patients with cerebrovascular diseases initiated by arterial hypertension and atherosclerosis of major cerebral arteries. NMRA image of arterial impairment comprise curved extracranial arteries. NMRT picture of the brain was changed (extension of liquor spaces, small hyperintensive foci in the white matter) in mild and moderate hypertension. Frequency of these phenomena and their severity increase with growing severity of the disease reaching maximum in malignant hypertension. In atherosclerosis of the major cerebral arteries NMRT often detected strokes, for the most part ischemic. A direct relationship between the degree of arterial stenosis and incidence of the strokes was not found. 相似文献
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IL Erokhina GV Selivanova TD Vlasova OI Emel'ianova 《Canadian Metallurgical Quarterly》1997,39(10):889-899
Cardiomyocytes of right auricle of human heart were obtained during open heart surgery from 5 patients (aged from 3.6 to 6 years) with congenital heart diseases (atrial septal defect and tetralogy of Fallot, group I), from 6 patients (aged from 20 to 49 years) with mitral valve disease (group II) and from 5 patients (aged from 40 to 54 years) with ischemic heart disease (group III). Ploidy and area of cells were measured in isolated myocytes after the Feulgen staining. The degree of ultrastructural changes in myocytes was evaluated by means of scoring system (0 to 3). The hearts of group I patients contain 55 to 82% of cells with 2c DNA, 18 to 41% of cells with 4c DNA and 0 to 4% of cells with 8c DNA. In the hearts of group II patients the level of cell ploidy is high: the share of 2c-cells varies from 1 to 24%, that of 4c-cells--from 1 to 55%, that of 8c-cells--from 13 to 57%, that of 16c-cells--from 1 to 39%, the share of cells with 32c and more DNA--from 3 to 47%. The ploidy of myocytes of group III patients is not high: 2c-cells make 35 to 55%, 4c-cells--39 to 55%, 8c-cells--5 to 15%. The average cell areas in group II are 4 times larger than in group I, and twice as large as in group III. In most cases, cells of all ploidy levels are larger in patients with higher average cell sizes. In all patients with increased ploidy levels, cells grow in size, but the rate of this growth is lower than that of cell DNA content. In all patients the myocytes with different degrees of organelle damage are observed. In patients of groups I and III there is a direct correlation between the extent of myocyte ploidy and hypertrophy, on the one hand, and the degree of cell degeneration, on the other hand. In contrast, in group II patients an inverse relation between ploidy and extent of degenerative changes of cells is evident. 相似文献