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1.
Khakass families can be considered as a fundamental ethnic determinant. Based on the family subdivision the analysis of intensity and genetic effectiveness of marriage migrations has revealed the speed of formation of a new ethnic-territorial community--Khakass nationality--on the territory of the Minusinsk hollow.  相似文献   
2.
A simplified method of manual calculation for inbreeding coefficient (and/or relationship) from complicated pedigree tables presented in a nongraphic mode is offered. The method is based on the use of positional dual codes of ancestors in which all genealogical links of the proband are reflected.  相似文献   
3.
Using the patch-voltage-clamp method action of tetraethylammonium on the fast (30 pS) and slow K+ channels was investigated. The slow K+ channels were presented by two types: with whole (30 pS) and decreased (20 pS) conductance. In all cases tetraethylammonium decreased the current magnitude and modified the channel kinetic parameters. Apparent blocking constants determined from the current decreasing are as 8-50 and 4-12 mM for the slow K+ channels with whole and decreased conductance, respectively, and 0.05-0.08 mM--for the fast K+ channel. The potential dependency of the blocking constants correlates with that of the channel conductance. Probability of the channel open state for the slow K+ channels decreases, and that for the fast K+ channel increases under application of tetraethylammonium. It is concluded that there are two sites of tetraethylammonium binding: the first site is into the channel pore, and the second one--into the regulatory centre responsible for the channel kinetic behaviour. Blocking of general conductance of the slow channels is accompanied by proportional decrease of the channel substate conductances without change of their number and cooperatively. Block of the fast K+ channel occurs without change of the channel elementary conductance but with decrease of the number of the channel substates and reversible violation of the channel transition cooperativity. The data are discussed from the point of the hypothesis on the channel clustery organization.  相似文献   
4.
Using the patch-voltage-clamp method kinetic parameters of single ionic channels were studied. It was found that the channels have long-lasting conductance substates along with the short-living ones. The conductance of a long-lasting substate fluctuates near an average sublevel in the boundaries of a restrict number (k) of elementary conductance steps. There is a direct relationship: the greater k, the longer is average duration (tau k) of the substate. For a given k the falling phase of tau k value distribution is approximately one-exponential. The substates of k-th order result in the multi-exponentiality of the ion current kinetics.  相似文献   
5.
Using the patch-voltage clamp technique and the rescaled range method, activity of single large conductance Ca2+-activated K+ channels (KCa channels) was studied. For the sequences of alternating open and shut time intervals, the dependence R/S vs. N in the double logarithmic coordinates presented a curve with two slopes, H1 =0.60 ± 0.04, and H2 = 0.88 ± 0.21, where H1 and H2 characterized the Hurst exponents for shot and long time ranges, respectively. Similar results were obtained for reduced data sets consisting of only open or only shut intervals. Randomization of the experimental data resulted in a single slope, H, of 0.52 ± 0.02. Simulations were performed with eight-state Markovian model without memory. The calculated Hurst exponent presented in average 0.54 ± 0.02. The results suggest that the activity of single Ca2+-activated K+ channel exhibits two regimes, with slight positive correlation at short time ranges (H1 =0.6), and strong positive correlation at long time ranges (H2 = 0.88); therefore the channel gating as a whole is not a steady-state Markovian process.  相似文献   
6.
Significant identity between a hypothetical 92.3-kD human protein and angiotensin-converting enzyme (ACE; peptidyl-dipeptidase A; kininase II) has been found. Certain specific regions of the 92.3-kD protein indicate that this unidentified molecule may be a member of the zinc metalloprotease family. A method is suggested for determination of a structural and functional family of proteins with unknown structure and function.  相似文献   
7.
Doklady Biological Sciences - Stress exposures during vegetation are known to reduce the yield in crops, but the intensity and duration of stress is rather difficult to determine from the crop...  相似文献   
8.
A novel method based on the maximum overlap wavelet transform of dwell time series is proposed. Information on local multifractal properties of the series, namely local Hurst exponents or Holder exponents, was obtained. The results confirm the presence of multifractality and intrinsic correlations in the Ca(2+)-activated K+ channel dwell time series. The data on the local multifractal structure of the series can be interpreted in terms of processes having self-organized criticality. The proposed approach allows one to widen the store of methods for the analysis of single ion channel activity.  相似文献   
9.
A comparative analysis of the proteins in prostate tissues of the patients operated for hyperplasia (n = 7) or cancer (n = 5) was performed aiming to search for protein diagnostic markers. Differences in several minor proteins were detected using two-dimensional electrophoresis according to O'Farrel; among them, an additional protein with a molecular weight of 19 kDa and an isoelectric point of 9.0 was observed in four of the cancer cases. Mass spectrometry allowed this protein to be identified as the androgen-induced secreted protein AGR2. The possibility of using AGR2 as a diagnostic marker of prostate cancer is discussed.  相似文献   
10.
Myocardial mast cells (MC) respond to cardiovascular pathology. The behavior of MC population in myocardium and pericardium of rats has been studied 24 h, 14, 28 and 60 days after two isoproterenol injections (at 24 h intervals). The extent of heart failure has been estimated by supersonic inspection 28 and 60 days after isoproterenol injections. The density of MCs of different degrees of maturity was estimated on paraffin sections stained with Alcian blue--Safranin. The MC density in myocardium of intact and experimental rats was relatively low: from 4 to 6 cells/mm2. The MC density in pericardium of intact rats was several times higher than in myocardium: 48.6 +/- 13.0 cells/mm2. In 24 h and 14 days after isoproterenol injections the pericardial MC density was 1.5 times higher than in control rats (P < 0.05) at the expense of increase in the number of mature MCs with Safranine-positive granules without the increase in the number of immature cells with Alcian blue-positive granules. In 28 days the pericardial MC density was 2 times higher than in intact rats (P < 0.05) at the expense of increase in number of immature and mature cells. In 60 days after isoproterenol injections the pericardial MC density and the ratio of immature and mature cells compared with control did not reach statistical significance. The changes in pericardial MC population corresponded to severity of heart failure according to functional indices. The findings show active reaction of pericardial MCs on myocardium dysfunction that stimulates the maturation of resident immature MCs in pericardium and migration of immature cells to pericardium of damage heart.  相似文献   
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