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Miriam R Faria Mara S Hoshida Eloisa AV Ferro Francesca Ietta Luana Paulesu Estela Bevilacqua 《Reproductive biology and endocrinology : RB&E》2010,8(1):95
Background
Macrophage migration inhibitory factor (MIF) has special pro-inflammatory roles, affecting the functions of macrophages and lymphocytes and counter-regulating the effects of glucocorticoids on the immune response. The conspicuous expression of MIF during human implantation and early embryonic development also suggests this factor acts in reproductive functions. The overall goal of this study was to evaluate Mif expression by trophoblast and embryo placental cells during mouse pregnancy. 相似文献514.
V E Illarionova T M Taratina L A Volkova S F Bartoshevich B V Moskvichev 《Prikladnaia biokhimiia i mikrobiologiia》1989,25(1):22-28
The gyration radius (R0) of native streptokinase (SK) was found to be R0 = (40 +/- ) A by small-angle X-ray scattering. Experimental hydrodynamic characteristics of SK were S0(20),W = (2.8 +/- 0.1)S; D0(20),W = (6.0 +/- 0.5) x 10(-7) cm2/s; [n] = 0.12 dl/g. The molecular weight of the enzyme was found to be 44,000. The values of the form factor R0/Rsphere = 2.1 and the frictional ratio f/f0 = 1.5 indicate considerable anisometry of the SK molecule. Basing on the curves of small-angle X-ray scattering of SK modified with a synthetic linear copolymer of N-vinylpyrrolidone (P) at a molar ratio SK less than P, a structural model of the conjugate was proposed. The modified form consisted of a dense nucleus covered with a diffuse polymeric membrane. In accordance with the model, R0 of modified SK and of the whole conjugate were found to be R0nucleus = (34 +/- 2) A and R0conjugate = (114 +/- 5)A. 相似文献
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M. B. Oboznaya O. M. Vol'pina M. N. Zhmak M. A. Titova T. D. Volkova A. A. Egorov S. S. Rybakov V. T. Ivanov 《Russian Journal of Bioorganic Chemistry》2004,30(4):320-326
Antibodies to the bovine prion protein were produced by immunizing mice of three lines with five synthetic fragments of the protein and six of their analogues. The analogues contained amino acid substitutions that, according to theoretical calculation, should lead to an increase in the immunogenic activity of peptides. All the peptides except for one induced the formation of antibodies. All the sera containing the antipeptide antibodies were tested by an immunohistochemical method. The sera effectively bound to brain preparations from an animal with spongiform encephalopathy were identified; it was shown that they do not interact with preparations of normal brain. Therefore, it was shown that the immunization of mice with synthetic fragments of a prion protein allows one to obtain specific antibodies suitable for the study and diagnostics of prion diseases. 相似文献
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V S Pashkov V N Maiorov V F Bystrov A N Hoang T M Volkova E V Grishin 《Biophysical chemistry》1988,31(1-2):121-131
1H-NMR spectra of Buthus eupeus neurotoxin M9 (66 amino acid residues, four disulfide bonds) reveal two slowly exchangeable conformations at acidic pH. The spatial structure of the conformer prevailing under physiologically relevant conditions has been determined from two-dimensional 1H-NMR data treated by means of a distance geometry algorithm and refined by molecular modelling. Interrelation between the structure and function of mammalian neurotoxin M9 is discussed by comparing its conformation with those of the scorpion insectotoxins which exhibit different biological specificity (insectotoxins v-2, v-3 and I5A). 相似文献
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The common primrose (Primula vulgaris, Primulaceae) has several color morphs. Two of them, traditionally treated as subspecies, vulgaris with white and yellow flowers, and polymorphic sibthorpii with the predominance of dark (anthocyanin-containing) flowers, often occur at the same places along the eastern Black Sea coast, stretching over 250?km between Novorossiysk and Pitsunda. Seventy-one primrose populations were sampled on almost every 10-km interval of this line. We found a significant trend of increase in the proportion of dark flowers in the populations from northwest to southeast, with an abrupt (60?km) transitional zone. Within this zone, we found significant spatial trends correlated with altitude and distance from seashore. No reliable morphological differences between color forms were found. The observed large-scale geographical structure may be a joint result of the recent contact of previously isolated color morphs, heterogeneity of pollinator preferences, and genetic drift. 相似文献
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