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1.
Yu. S. Ravkin S. M. Tsybulin S. G. Livanov K. V. Toropov V. N. Kuranova V. P. Starikov S. V. Chesnokova 《Contemporary Problems of Ecology》2008,1(5):568-573
For the entire territory of West Siberia, including its plain and mountainous parts, two maps were constructed for populations of amphibians together with reptiles, and of birds. Communities of these classes of vertebrates differ from one another in their spatial differentiation. The differences are demonstrated for the plain and mountainous territories considered jointly and separately. 相似文献
2.
Strategies for rare-event detection: an approach for automated fetal cell detection in maternal blood. 总被引:3,自引:0,他引:3 下载免费PDF全文
J C Oosterwijk C F Knepfl W E Mesker H Vrolijk W C Sloos H Pattenier I Ravkin G J van Ommen H H Kanhai H J Tanke 《American journal of human genetics》1998,63(6):1783-1792
This article explores the feasibility of the use of automated microscopy and image analysis to detect the presence of rare fetal nucleated red blood cells (NRBCs) circulating in maternal blood. The rationales for enrichment and for automated image analysis for "rare-event" detection are reviewed. We also describe the application of automated image analysis to 42 maternal blood samples, using a protocol consisting of one-step enrichment followed by immunocytochemical staining for fetal hemoglobin (HbF) and FISH for X- and Y-chromosomal sequences. Automated image analysis consisted of multimode microscopy and subsequent visual evaluation of image memories containing the selected objects. The FISH results were compared with the results of conventional karyotyping of the chorionic villi. By use of manual screening, 43% of the slides were found to be positive (>=1 NRBC), with a mean number of 11 NRBCs (range 1-40). By automated microscopy, 52% were positive, with on average 17 NRBCs (range 1-111). There was a good correlation between both manual and automated screening, but the NRBC yield from automated image analysis was found to be superior to that from manual screening (P=.0443), particularly when the NRBC count was >15. Seven (64%) of 11 XY fetuses were correctly diagnosed by FISH analysis of automatically detected cells, and all discrepancies were restricted to the lower cell-count range. We believe that automated microscopy and image analysis reduce the screening workload, are more sensitive than manual evaluation, and can be used to detect rare HbF-containing NRBCs in maternal blood. 相似文献
3.
Distribution of black grouse and hazel grouse was evaluated on the basis of the results of bird counts from July 16 to August
31, 1959–2005 over all natural geographical zones and subzones of West Siberia (with fractioning down to the type of landscape
tract). Data averaging over groups of vegetation map units (dynamic series) and other specific averaging procedures revealed
that black grouse is common in northern-, middle-, and southern-taiga bogs; in subtaiga pine forests; in grassy bogs combined
with halophytic meadows within the boundaries of subtaiga forests and the northern forest-steppe; and in agricultural lands
in the northern forest-steppe. Hazel grouse is numerous in southern-taiga and dark coniferous middle-taiga forests and their
derivatives. The number of hazel grouse individuals in these habitats is larger than in other lands. In general, over the
subzones, both black grouse and hazel grouse are most numerous in the middle and southern taiga and in subtaiga forests. To
the north and to the south of these subzones, the abundance of these species decreases. They were not encountered in tundras
and some open forest-steppe and steppe habitats. 相似文献
4.
Yu. S. Ravkin L. G. Vartapetov V. A. Yudkin S. P. Milovidov K. V. Toropov S. M. Tsybulin V. S. Zhukov B. N. Fomin A. M. Adam I. V. Pokrovskaya A. A. Ananin P. A. Panteleev S. A. Solov'ev A. A. Vakhrushev E. S. Ravkin T. K. Blinova E. L. Shor D. M. Polushkin A. B. Kozlenko V. M. Anufriev G. M. Tertitskii 《Biology Bulletin》2001,28(3):301-310
The proposed classification system reflects the difference between the three population systems: unbuilt land, built-up land, and aquatic–semiaquatic communities. Two superorder groups—north and median—further divided into types were recognized in each of the systems. Most types are divided into subtypes, classes, and subclasses (and sometimes genera of the population). The estimation of the power and generality of the influence of environmental factors (their variability correlates with heterogeneity of the avian population) has demonstrated that forestation of the territory is most significant in the first half of summer on the western Siberian Plain. The composition of the forest-forming species and zoning are less affected. The influence of moisture and hydration is 2–3 times less significant; mesorelief is 4–5 times less significant; and productivity (feeding capacity) and anthropogenic influence are 7–9 times less significant. 相似文献
5.
A new approach to the analysis of the neuroendocrine system (NES) is suggested. It is based on the fact of structural and metabolic determination of any effect on cell and cell aggregates. The principle of a common communication channel in the NES is formulated and a possible method of its formalization is proposed. 相似文献
6.
An automated unit for manually controlled photometry and morphometry is described. It enables the operator to carry out photometrical measurements according to the plug-method and morphometrical measurements with the help of an object-micrometer or some kind of a grid. The data obtained are stored in the "Elektronika D3-28" microcomputer to be statistically evaluated after the end of sampling. New variables can be obtained defined by the user as a product of some source variables or their inverses. The data and control structures of the system are described in detail. 相似文献
7.
Use of automated microscopy for the detection of disseminated tumor cells in bone marrow samples 总被引:5,自引:0,他引:5
The use of automated microscopy has reached the maturity necessary for its routine use in the clinical pathology laboratory. In the following study we compared the performance of an automated microscope system (MDS) with manual method for the detection and analysis of disseminated tumor cells present in bone marrow preparations from breast carcinoma patients. The MDS System detected rare disseminated tumor cells among bone marrow mononuclear cells with higher sensitivity than standard manual microscopy. Automated microscopy also proved to be a method of high reproducibility and precision, the advantage of which was clearly illustrated by problems of variability in manual screening. Accumulated results from two pathologists who had screened 120 clinical slides from breast cancer patients both by manual microscopy and by use of the MDS System revealed only two (3.8%) missed by the automatic procedure, whereas as many as 20 out of 52 positive samples (38%) were missed by manual screening. 相似文献
8.
Distributions of amphibian and reptile faunas were separately delimited on a 1:20 000 000 vegetation map of Northern Eurasia
divided into 245 10-degree-longitudinal segments of native subzone within the USSR borders as of 1990. All reptile and amphibian
species recorded in every segment were listed, and the Jaccard indices were calculated, and the similarity matrix was studied
with cluster analysis. Hierarchic classifications were made: the amphibian one consisting of 3 faunistic regions, divided
into 4 subregions, 7 biologic provinces, and 23 districts. The reptile classification includes 4 faunistic regions, 7 subregions,
18 provinces, and 14 districts. The reptile classification has 1.5 times more provincial and district subdivisions than amphibian
one. Environmental factors correlating with faunistic nonuniformity were revealed. Our amphibian and reptile schemes are 1.9
and 3.5 times more informative than those proposed earlier and account for 75 and 91% of variance in the faunal similarity
coefficient of specific areas, respectively (multiple correlation coefficients 0.87 and 0.95). Environmental factors can explain
84 and 93% of faunistic nonuniformity (correlation coefficients 0.95 and 0.96). 相似文献
9.
Yu. S. Ravkin I. N. Bogomolova S. M. Tsybulin T. K. Zheleznova K. V. Toropov L. G. Vartapetov S. P. Milovidov V. A. Yudkin V. S. Zhukov S. P. Gureev I. V. Pokrovskaya E. Sh. Kasibekov A. A. Ananin E. N. Bochkareva 《Contemporary Problems of Ecology》2016,9(1):86-97
The area under study covered the West Siberian Plain from the Urals to the Yenisei River and the same band to the southern borders of the former Soviet Union in 1991, including a part of the Altai-Sayan mountain country, Kazakhstan, Uzbekistan, Turkmenistan, and the whole of Kyrgyzstan and Tajikistan. The results of ornithogeographic surveys carried out on routes with a length of 63000 km in 3140 habitats from May 16 to July 31 in the period from 1936 to 2013 were analyzed for this territory. More than 110 specialists took part in the study. The collected data were averaged according to the contours of natural-geographical maps. The subsequent cluster analysis revealed the presence of three systems (series) of bird communities in undeveloped and developed lands, as well as in water and riparian areas. Eight types of communities were distinguished within the first system: 1—tundra type; 2—forest-tundra type; 3—forest type; 4 and 5—West Siberian meadow-steppe and semidesert-steppe types; 6 and 7—Middle Asian northern desert-steppe and southern desert types; 8—high-mountain type. The borders of their distribution do not coincide with the zonal borders. Seven and six types of communities were distinguished in the second and third systems, respectively. A part of them was divided into 29 subtypes in total. The revealed heterogeneity of bird communities is largely determined by 12 environmental factors. The greatest correlation was detected for forestation, buildup, and watering. The multiple correlation of the bird population variability with all the identified environmental factors amounted to about 54 ± 1% of variance in the similarity matrix, which approximately corresponds to the correlation coefficient of 0.74. 相似文献
10.
A.?G.?ShiryaevEmail author Yu.?S.?Ravkin V.?M.?Yefimov I.?N.?Bogomolova S.?M.?Tsybulin 《Contemporary Problems of Ecology》2016,9(5):535-543
The spatial heterogeneity of mycobiota species composition has been studied. Clavarioid fungi are used as a model group for mycobiota zonation of Northern Eurasia. The differences in the classification of mycobiota of these fungi resulting from the used coefficients of similarity, aggregation algorithms, and opinions of different interpreters are shown. A method of combining different classifications is proposed. A further study on a larger number of fungal groups would be more representative and would contribute to the creation of a unified biogeographic zonation of Northern Eurasia. 相似文献