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The paper presents an analysis of the results of a comprehensive clinical and instrumental examination (poly- and apex-cardiography) of 156 patients with essential hypertension (Stages I, I-II and II, according to L.I. Fogelson's classification) and of 40 normal individuals, that was undertaken to study the functional state and the reserves of the left ventricular myocardium. The disorders in the functional state and the reduction of the reserve capacity were shown to progress along with the stage of the disease. The clinical and labour prognosis of the patients with essential hypertension depend on the character of its course, stage of the disease, degree of functional disorders and reserve capacity of the myocardium, as well as on the profession and labour conditions. The employment of a broad complex of cardiological diagnostic techniques at rest and following dosaged bicycle ergometric load helps to determine the clinical and labour prognosis with greater precision and more objectively, and to solve the problems of timely employment of hypertensive patients.  相似文献   
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Gradient-based algorithms for global motion estimation are effective in many image-processing tasks. However, when analytical estimation of derivatives of objective function is not possible, linear search based algorithms such as Powell perform better than the gradient-based ones. In this paper we propose global motion estimation algorithm that exploits linear search based algorithm, particularly Powell, instead of commonly used gradient-based one. We also introduce a new approach for extracting global motion parameters called Two Step Powell-based GME. Using this approach we further improve the Powell-based GME. The proposed Powell-based GME outperforms Gauss–Newton algorithm (gradient-based) in terms of PSNR. The proposed Two Step Powell GME algorithm outperforms Powell-based GME in terms of PSNR and computational time.  相似文献   
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During pregnancy, uterine NK cells interact with trophoblast cells. In addition to contact interactions, uterine NK cells are influenced by cytokines, which are secreted by the cells of the decidua microenvironment. Cytokines can affect the phenotypic characteristics of NK cells and change their functional activity. An imbalance of pro- and anti-inflammatory signals can lead to the development of reproductive pathology. The aim of this study was to assess the effects of cytokines on NK cells in the presence of trophoblast cells in an in vitro model. We used TNFα, IFNγ, TGFβ and IL-10; the NK-92 cell line; and peripheral blood NK cells (pNKs) from healthy, non-pregnant women. For trophoblast cells, the JEG-3 cell line was used. In the monoculture of NK-92 cells, TNFα caused a decrease in CD56 expression. In the coculture of NK cells with JEG-3 cells, TNFα increased the expression of NKG2C and NKG2A by NK-92 cells. Under the influence of TGFβ, the expression of CD56 increased and the expression of NKp30 decreased in the monoculture. After the preliminary cultivation of NK-92 cells in the presence of TGFβ, their cytotoxicity increased. In the case of adding TGFβ to the PBMC culture, as well as coculturing PBMCs and JEG-3 cells, the expression of CD56 and NKp44 by pNK cells was reduced. The differences in the effects of TGFβ in the model using NK-92 cells and pNK cells may be associated with the possible influence of monocytes or other lymphoid cells from the mononuclear fraction.  相似文献   
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