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1.
Electrocardiographic symptoms were evaluated in 53 patients with an additional left-ventricular chorda (ALVC), detected by two-dimensional echocardiography. Signs of early ventricular repolarization (EVR) were identified in 45 (84.9%) patients. A transverse ALVC was more common in EVR-free patients (87.5%), as compared to patients with ALVC + EVR combinations (51.1%; p less than 0.05).  相似文献   
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Operator's determined (D) and stochastic (S) performance depends on the level of readiness and synchronization of the frontoparietal and parietooccipital cortex areas. The developed feedback algorithm was tested in two series of experiments with volunteered subjects doing computer simulation tasks. The experiments showed feasibility to elaborate feedback adaptive control skills that will sustain for a month period.  相似文献   
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The second generation of the scintillation gamma camera gamma KC-2 has been recently produced in lots. Compared to the first Soviet model gamma KC-1 it features advanced spatial resolution, maximum count rate, and image uniformity. A built-in microprocessor controls in real time corrections for distortions thus providing a marked gain in serviceability and expanded diagnostic capacity.  相似文献   
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Cyclic peptide disulfides of the general formula were synthesized from the corresponding peptide derivatives [Boc-Cys(Trt)(Gly)-n-Cys(Trt)-OBut] by oxidation with iodine in methanol and by subsequent removal of the terminal groups with trifluoroacetic acid. Acid ionization constants of the obtained peptides were determined by potentiometric titration in aqueous KCl (0.1 mol/L) medium. All compounds have two dissociable hydrogens, corresponding to carboxyl (pK1= 2.35–2.84) and to terminal amino group (pK2= 5.61–6.93); pK1, values show first an upward and then a downward trend with the increase in ring size; the opposite is true for pK2, values. These trends could be tentatively attributed to the intramolecular salt bridge (-COO——-NH+3-) formation.  相似文献   
6.
The accumulation of macrophage foam cells in atherosclerotic lesions is associated with both initiation and progression of this disease. Scavenger receptors CD36 and SRA are the primary receptors responsible for conversion of macrophages into foam cells. Integrin alphaVbeta3 plays a role in the differentiation of several cell types, but its involvement in the transition of macrophages into foam cells and the potential role of this receptor in atherosclerosis have not been examined. Using an in vitro model of single surface receptor activation by binding with an immobilized monoclonal antibody specific to alphaVbeta3 integrin we show that ligation of alphaVbeta3 integrin prevents differentiation of blood monocytes and macrophages into the foam cell phenotype via coordinate down-regulation of CD36 and SRA. This effect of alphaVbeta3 integrin ligation can be reproduced by contact with endothelial cells, whereas the inhibition of alphaVbeta3 receptor ligation restores the uptake of oxidized low-density lipoprotein. Moreover, we found that alphaVbeta3 integrin is readily detected in situ on macrophages in early and advanced atherosclerotic lesions and that in vitro exposure to oxidized low-density lipoprotein up-regulates alphaVbeta3 integrin expression. We hypothesize that alphaVbeta3 integrin regulates macrophage functional maturation into foam cells in a persistent manner, and therefore, by targeting alphaVbeta3 receptor it could potentially be possible to regulate progression of atherosclerosis in humans.  相似文献   
7.
Hexokinase and glucokinase activity in the supernatant of a rabbit liver homogenate obtained at 18,000g was determined by a spectrophotometric method. Preliminary purification to remove low-molecular-weight components by gel filtration on Molselect G-50 dextran was shown to prevent reduction of NADP unconnected with the hexokinase reaction.Presented by Academician of the Academy of Medical Sciences of the USSR V. S. Il'in.Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 7, pp. 891–892, July, 1976.  相似文献   
8.
Endocrine functions were investigated in normotensive (Wistar) and hypertensive (NISAG) rats before and on days 3, 7, and 21 after subcutaneous epinephrine administration. Rats of the NISAG strain are characterized by elevated plasma levels of aldosterone and thyroxine and lowered plasma levels of immunoreactive insulin, and their endocrine system develops a much stronger response to a single epinephrine injection than does that of Wistar rats. This is manifested in a still higher aldosterone level, elevated corticosterone and insulin concentrations, and reduced thyroxine content in the plasma. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 495–498, May, 1996  相似文献   
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