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921.
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
922.
N Durán Y Makita L H Innocentini 《Biochemical and biophysical research communications》1979,88(2):642-648
The presence of enzymically generated triplet acetone in red cells and energy transfer to eosin, rose bengal and 9,10-dibromoanthracene-2-sulfonate was indicate by: (1) product distribution; (2) KET τo, similar to the 2-methylpropanal/peroxidase/O2 system; (3) correlation between hemolysis, oxygen uptake and photon emission; (4) membrane protection by energy acceptors, and (5) by comparison of the 2-methylpropanal/peroxidase/O2 system with 2-methylpropanal/red cells/membranes/O2 and 2-methylpropanal/acid extractable protein from red cells membrane/O2 systems, which have a high peroxidase activity.This is the first report of a biological system producing a photohemolysis effect in the dark. 相似文献
923.
V. S. Kurbanismailov O. A. Omarov G. B. Ragimkhanov M. Kh. Gadzhiev M. G. Bairkhanova A. J. Kattaa 《Plasma Physics Reports》2011,37(13):1166-1172
The experimental results on the formation and development of initial stages of an impulse breakdown in atmospheric-pressure
argon at townsend and streamer breakdown mechanisms for different initial conditions are presented. A streamer channel is
shown to be initiated by bright luminescence formed at the point of critical avalanche amplification at different distances
from the cathode depending on overvoltage. Prebreakdown currents are experimentally measured for the townsend and streamer
breakdown mechanisms and peculiarities of spark channel formation for these mechanisms are studied. 相似文献
924.
Merkel cell tumor: diagnosis, prognosis, and management 总被引:2,自引:0,他引:2
The histologic features of the Merkel cell and the pathologic characteristics of the Merkel cell tumor are described. From a literature review, 68 cases are examined; 23 cases that have been followed up accurately are presented from the Mayo Clinic. A representative case is used to demonstrate the problems of diagnosis and suggested treatment. The latter should be wide local resection with removal of nodal metastases if present. When indicated, this should be followed up with radiation therapy. Chemotherapy is of little or no value. Survival rates are presented. 相似文献
925.
926.
The paper analyzes humus profiles of mountain-chestnut soils of a complex catena situated within the Khemchik dry-steppe area
of the Central Tuva Depression. The study has shown that humus profile characteristics are determined by both slope aspects
and position in the catena. Humus profiles imprint all environmental changes of soil formation and functioning even if these
changes are not expressed in soil morphology. The materials obtained during the study may serve as basis for long-term monitoring
of slope soil behavior and for revealing local soil variability in changing environment. 相似文献
927.
R M Dixon B T Golding S Mwesigye-Kibende D N Ramakrishna Rao 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》1985,311(1152):531-544
The vitamin B12 coenzyme adenosylcobalamin assists the enzymic catalysis of molecular rearrangements of the type (formula; see text) in which the migrating group X can be OH, NH2 or a suitable substituted carbon atom such as C(=CH2)CO2H. This paper discusses evidence for the participation of organic radicals as intermediates in these reactions. Theoretical and model studies supporting the intermediacy of radicals in the reactions catalysed by the enzymes diol dehydratase and alpha-methyleneglutarate mutase are described. For the model studies, alkyl radicals, alkylcobaloximes (alkyl represents, for example, ethoxycarbonyl substituted, but-3-enyl and cyclopropylmethyl) and also dihydroxyalkylcobalamins have been investigated. The Co-C alpha-C beta angle of 125 degrees in adenosylcobalamin is shown to be an 'especial' angle by analysis of the crystal structures of R- and S-2,3-dihydroxypropylcobalamin. 相似文献
928.
929.
Mamta Singhvi Dipti Joshi Shalaka Gaikaiwari Digambar V. Gokhale 《Indian journal of microbiology》2010,50(1):97-100
Method for production and regeneration of Lactobacillus delbrueckii protoplasts are described. The protoplasts were obtained by treatment with a mixture of lysozyme and mutanolysin in protoplast
buffer at pH 6.5 with different osmotic stabilizers. The protoplasts were regenerated on deMan, Rogosa and Sharpe (MRS) with
various osmotic stabilizers. Maximum protoplast formation was obtained in protoplast buffer with sucrose as an osmotic stabilizer
using a combination of lysozyme (1 mg/ml) and mutanolysin (10 μg/ml). Maximum protoplast regeneration was obtained on MRS
medium with sucrose (0.5 M) as an osmotic stabilizer. The regeneration medium was also applicable to other species of lactobacilli
as well. This is, to our knowledge, the first report on protoplast formation and efficient regeneration in case of L. delbrueckii. 相似文献
930.
It is generally perceived that landscape patterns or textures in a given protected area are spatially stationary. The findings
of this study suggest that this common perception is only partially correct. Over the course of 52 years, equilibrium in landscape
shifting was detected using digital data for the Lassen Volcanic National Park (USA). Vertical aerial photographs taken of
the park in 1941 were geo-referenced with the digital orthophoto quarter quadrangle (DOQQ) images of the same area from 1993
to identify landscape compositions and to measure change. Spatial analysis was used to observe pattern changes over time.
The results suggested that landscape development maintained equilibrium while patches were in various stages of a successional
sequence. The total area of each landscape component held steady, although over time patches throughout the landscape changed—a
shifting-mosaic steady state (SMSS). These findings reflect the limitations of contemporary environmental conservation theory.
They also suggest the importance of considering landscape change in policies that currently govern park planning and management. 相似文献