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1.
It is established that carboxypeptidase H activity increases as affected by various stress factors in the rat brain departments. The increase of the enzyme activity because of the emotional-pain stress is of continuous character. Possible role of carboxypeptidase H in the development of the stress response is discussed. 相似文献
2.
The thermotropic properties of multilamellar liposomes from egg yolk lecithin, hydrogenized egg yolk lecithin and several mixtures of these two lipids were studied with the application of excimer--forming optical probe pyrene and microcalorimetry. It was discovered that when the proportion of the egg yolk lecithin in the lipid mixture was raised the temperature of the main phase transition reduced. For all this, independent of the lipid mixture composition when the temperature was raised, apparently, polarity of pyrene microenvironment in the liposomes bilayers decreased. On the basis of the analysis of solidus and liquidus curves obtained from calorimetric studies of the lipid mixtures and bend points of Arrhenius anamorphose obtained during the pyrene excimer formation measurements some conclusions were made about the role of unmodified and hydrogenized egg yolk lecithin cluster formation in the determination of thermotropic properties of the liposomes from the above two lipids mixtures. High temperature phase transition discovered for the egg yolk lecithin while measuring the pyrene excimer formation is proposed to be closely connected with temperature-dependent changes in the organization of phospholipid heads on the interphase bilayer/H2O solution. 相似文献
3.
V Z Tarantul V V Kucheriavy? I V Makarova Iu N Baranov T V Begetova 《Molekuliarnaia biologiia》1986,20(1):278-287
The "plasmid rescue" method has been used to isolate the recombinant plasmid pMA3 fragment and flanking sequences from the transgenic mouse genome containing the fragment in integrated form. The "rescued" plasmid, pMAR1, lacks all virus sequences and retains only those regions of pBR322 that are responsible for the plasmid replication and Escherichia coli ampicillin resistance. The plasmid pMA3 deletion has occurred at its integration into the mouse genome after microinjection into the zygote. The integrated fragment of the plasmid is adjacent to the genome repeated sequence that is highly conservative in evolution. 相似文献
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5.
Fushitani K; Higashiyama K; Moriyama EN; Imai K; Hosokawa K 《Molecular biology and evolution》1996,13(7):1039-1043
To elucidate phylogenetic relationships among amniotes and the evolution of
alpha globins, hemoglobins were analyzed from the Komodo dragon (Komodo
monitor lizard) Varanus komodoensis, the world's largest extant lizard,
inhabiting Komodo Islands, Indonesia. Four unique globin chains (alpha A,
alpha D, beta B, and beta C) were isolated in an equal molar ratio by high
performance liquid chromatography from the hemolysate. The amino acid
sequences of two alpha chains were determined. The alpha D chain has a
glutamine at E7 as does an alpha chain of a snake, Liophis miliaris, but
the alpha A chain has a histidine at E7 like the majority of hemoglobins.
Phylogenetic analyses of 19 globins including two alpha chains of Komodo
dragon and ones from representative amniotes showed the following results:
(1) The a chains of squamates (snakes and lizards), which have a glutamine
at E7, are clustered with the embryonic alpha globin family, which
typically includes the alpha D chain from birds; (2) birds form a sister
group with other reptiles but not with mammals; (3) the genes for embryonic
and adult types of alpha globins were possibly produced by duplication of
the ancestral alpha gene before ancestral amniotes diverged, indicating
that each of the present amniotes might carry descendants of the two types
of alpha globin genes; (4) squamates first split off from the ancestor of
other reptiles and birds.
相似文献
6.
An agar-diffusion method for determination of oleandomycin and tetracycline low levels in solutions of the drug combination was developed. The medhod may be used for investigation of oletetrin absorption and distribution in humans and animals. It provides high accuracy in separate determination of oleandomycin and tetracycline activity in solutions of the drugs at a ratio of 1 : 2. The same test-culture, Bac. subtilis, variant L2 is used for the assay of tetracycline and oleandomycin activity. The only differences are in the values of pH and the buffer solution and the standards. 相似文献
7.
G G Kublis E A Porunkevich A A Skuin'sh N A Makarova I P Misin'sh V E Klusha G I Chipens 《Biokhimii?a (Moscow, Russia)》1977,42(4):616-621
A comparative study of structural and functional organization of the polypeptides -- ACTH and wasp kinin was made. The effects of fragments Lys 17, 18-ACTH11(-18)-NH2--(I) and WK4(-12)--(II), possessing "common" fragments and a cluster of basic amino-acids, on the lipolytic and steroidogenic effects of ACTH and myotropic effects of bradykinin were studied. Both fragments I and II potentiate ACTH-induced lipolysis and steroidogenesis in isolated rat fat and adrenal cells but suppress the myotropic effect of bradykinin on guinea pig ileum. The similarity of biological effects of ACTH and WK fragments support our supposition on the similarity in structurally functional organization of these peptides. 相似文献
8.
Makarova Kira S.; Mazin Alexander V.; Wolf Yury I.; Soloviev Victor V. 《Bioinformatics (Oxford, England)》1992,8(5):425-431
A computer system DIROM for oligonucleotide-directed mutagenesisand artificial gene design has been designed for better experimentalplanning and control. DIROM permits searching for optimal oligonucleotideswith respect to certain important parameters, namely sufficientenergy of oligonucleotide-target hybridization, the secondarystructure of oligonuc-tide and target DNA, the presence of alternatebinding sites in the target DNA and terminal G/C pairs. It canalso be used to plan polymerase chain reaction experiments,for optimal primer selection, in sequencing, etc. DIROM enablesone to search for both existing and potential restriction sites,to perform vector + target sequence construction. The systemconsists of a set of original algorithms that formalize theempirical knowledge of oligonucleotide action as primers. 相似文献
9.
10.