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1.
The phosphorescence of dihydrooctaethylporphin (octaethylchlorin or OEC), of its complexes with magnesium, zinc, copper and palladium, and of zinc and palladium complexes of isobacteriooctaethylchlorin (5,6,7,8-tetrahydrooctaethylporphin with adjacent hydrogenated pyrrole rings or THOEP-ADJ) has been investigated. The phosphorescence spectra and phosphorescence excitation spectra as well as the ratio of fluorescence and phosphorescence yields and the triplet state lifetume have been measured. It has been shown that the singlet-triplet interval is about 4100 cm-1 for OEC complexes and about 4300 cm-1 for THOEP-ADJ complexes, and depends wealky on the nature of the metal atom forming the complex. The triplet level position of chlorophyll alpha is discussed. It is concluded that the maximum of chlorophyll alpha phosphorescence spectrum must be located at 895 nm.  相似文献   
2.
Lactobacillus gasseri K7 is a probiotic strain that produces bacteriocins gassericin K7 A and K7 B. In order to develop a real-time quantitative PCR assay for the detection of L. gasseri K7, 18 reference strains of the Lactobacillus acidophilus group and 45 faecal samples of adults who have never consumed strain K7 were tested with PCR using 14 pairs of primers specific for gassericin K7 A and K7 B gene determinants. Incomplete gassericin K7 A or K7 B gene clusters were found to be dispersed in different lactobacilli strains as well as in faecal microbiota. One pair of primers was found to be specific for the total gene cluster of gassericin K7A and one for gassericin K7B. The real-time PCR analysis of faecal samples spiked with K7 strain revealed that primers specific for the gene cluster of the gassericin K7 A were more suitable for quantitative determination than those for gassericin K7 B, due to the lower detection level. Targeting of the gassericin K7 A or K7 B gene cluster with specific primers could be used for detection and quantification of L. gasseri K7 in human faecal samples without prior cultivation. The results of this study also present new insights into the prevalence of bacteriocin-encoding genes in gastrointestinal tract.  相似文献   
3.
In the herds of Ayrshire and Black Pied cattle breeds of Russian selection, comparative analysis of allelic distribution of BoLA-DRB3 was performed in animal groups with different status of persistent lymphocytosis (PL) caused by the bovine leukemia virus (BLV). Alleles were typed by PCR–RFLP. Different spectra of BoLA-DRB3 alleles mediating susceptibility and resistance to leukemia were detected in the studied breeds. The role of amino acid motives in 1 domain of BoLA-DRB3 antigens was confirmed: ER (in positions 70–71), in resistance to leukemia and VDTY and VDTV (75–78), in susceptibility to leukemia. The nucleotide sequence of allele BoLA-DRB3.2*7with deletion of codon 65, which resulted in the changed conformation of the corresponding antigen molecule, was associated with resistance to PL. Cows of Black Pied and Ayrshire breeds with genotypes coding VDTY/VDTV (RR = 11.67, P = 0,014) and VDTY/VDTY (RR = 4.71, P = 0.022), respectively, were shown to be susceptible to PL. The role of heterozygosity level was demonstrated (estimated by BoLA-DRB3 alleles and by amino acid motives in positions 75–78 of the antigen) as an unspecific factor of resistance to PL. The lowest heterozygosity level by amino acid motives (75–78) was revealed in PL animals, for which sample inbreeding coefficients were detected: F = 0.324 and 0.084 in Ayrshire and Black Pied breeds, respectively.  相似文献   
4.
Summary The enzymatically activated agaroses compared with chemically activated show 25 fold lower amount of generated aldehyde groups, 33 fold lower binding capacity for chymotrypsin, 3 fold lower proteolytic as well as amidolytic activity toward AntAlaAlaPheNA of the corresponding fixed enzyme. Trans-cinnamoylimidazole titration data demonstrate 100% active bound enzyme in the case of enzymatically oxidized agaroses and 57% for chemically oxidized. The enzymic activation offers a small number of sites for ligand attachment in a unique microenvironment. The chemical activation yields a suitable matrix for effective chymotrypsin immobilization.  相似文献   
5.
In the samples of Russian Ayrshire and Gorbatov Red cattle breeds, distribution of frequencies of prolactin (PRL) gene alleles generated due to the presence of polymorphic RsaI site in exon 3 were studied. In the breeds, the frequencies of the Ballele of the PRLgene (with RsaI(+) site) detected by the PCR–RFLP method were 14.1 and 8.6%, respectively. In Black Pied, Ayrshire and Gorbatov Red cattle breeds, variation of the microsatellite dinucleotide repeat in the regulatory region of the gene PRLwas also studied. Gorbatov Red breed was monomorphic at the microsatellite locus with the only allele 164 bp in length. Two alleles (164 bp and 162 bp) were detected in the other breeds studied. The frequencies of 164-bp allele of the microsatellite locus were 93.7 and 90.0% in Black Pied and Ayrshire breeds, respectively. In Gorbatov Red breed of dairy type with good beef qualities and low milk-fat yield, lower level of heterozygosity for PRLgene was demonstrated compared to Ayrshire and Black Pied breeds that have high milk-fat yield. In three cattle breeds, higher mean estimate of polymorphism information content of PCR–RFLP in exon 3 (PIC = 0.21) was revealed compared with the same estimate (PIC = 0.09) for the microsatellite locus variability in the regulatory region of the PRLgene. Characteristics of allele Bdistribution of thePRLgene in the representatives of the Bovidae family are considered.  相似文献   
6.
In the herds of Ayrshire and Black Pied cattle breeds of Russian selection, comparative analysis of allelic distribution of BoLA-DRB3 was performed in animal groups with different status of persistent lymphocytosis (PL) caused by the bovine leukemia virus (BLV). Alleles were typed by PCR-RFLP. Different spectra of BoLA-DRB3 alleles mediating susceptibility and resistance to leukemia were detected in the studied breeds. The role of amino acid motives in beta 1 domain of BoLA-DRB3 antigens was confirmed: ER (in positions 70-71), in resistance to leukemia and VDTY and VDTV (75-78), in susceptibility to leukemia. The nucleotide sequence of allele BoLA-DRB3.2*7 with deletion of codon 65, which resulted in the changed conformation of the corresponding antigen molecule, was associated with resistance to PL. Cows of Black Pied and Ayrshire breeds with genotypes coding VDTY/VDTV (RR = 11.67, P = 0.014) and VDTY/VDTY (RR = 4.71, P = 0.022), respectively, were shown to be susceptible to PL. The role of heterozygosity level was demonstrated (estimated by BoLA-DRB3 alleles and by amino acid motives in positions 75-78 of the antigen) as an unspecific factor of resistance to PL. The lowest heterozygosity level by amino acid motives (75-78) was revealed in PL animals, for which sample inbreeding coefficients were detected: F = 0.324 and F = 0.084 in Ayrshire and Black Pied breeds, respectively.  相似文献   
7.
Distribution of BoLA-A antigens and BoLA-DRB3 alleles was studied by means of the microlymphocytotoxic test (BoLA-A) and the PCR-RFLP method (BoLA-DRB3) using restriction endonucleases RSAI, HaeIII, and XhoII in Ayrshire (n = 127) and Black Pied (n = 129) cattle breeds. Comparative analysis of profiles for class I antigens revealed significant differences in the frequencies of antigens W2, W6, W10, W31, W44, W15, and W19 (P > 99%). The studied breeds also differ in the spectrum of BoLA-DRB3 alleles and distribution of their frequencies. Heterogeneous allele frequency profile was detected in Ayrshire cattle: five of 18 detected alleles (DRB3.2*7, *8, *10, *24, and *28) accounted for 77%. Allele DRB3.2*7 (37.6%), which is classed with rare alleles in Black Pied cattle is the most common in Ayrshire cattle. The observed heterozygosity level in the combined sample of Black Pied breed (0.836) is higher than in Ayrshire breed (0.070). In both breeds, the heterozygosity level was studied in the groups of healthy and ill with persistent lymphocytosis (caused by bovine leukemia virus) animals and in the group of virus carriers in Ayrshire breed. In ill animals, a decrease in the observed heterozygosity level was detected, as compared to healthy animals and the expected heterozygosity level. The observed heterozygosity level exceeds the expected one in virus carriers. The detected features of the heterozygosity level in the studied groups allow the heterozygosity level for locus BoLA-DRB3 to be considered a nonspecific factor of resistance to leukemia and are heterozygous animals to have higher resistance to bovine leukemia. The presence of a larger proportion of highly productive animals (the annual productivity of more than 7000 kg) in the group of ill Ayrshire cattle animals, as compared to healthy animals to established. To increase resistance to bovine leukemia, the obtained data indicate the importance of the control of heterozygosity level and genetic diversity for gene BoLA-DRB3 in cattle herds.  相似文献   
8.
In the samples of Russian Ayrshire and Gorbatov Red cattle breeds, distribution of frequencies of prolactin (PRL) gene alleles generated due to the presence of polymorphic RsaI site in exon 3 were studied. In the breeds, the frequencies of the B allele of the PRL gene (with RsaI(+) site) detected by the PCR-RFLP method were 14.1 and 8.6%, respectively. In Black Pied, Ayrshire and Gorbatov Red cattle breeds, variation of the microsatellite dinucleotide repeat in the regulatory region of the gene PRL was also studied. Gorbatov Red breed was monomorphic at the microsatellite locus with the only allele 164 bp in length. Two alleles (164 bp and 162 bp) were detected in the other breeds studied. The frequencies of 164-bp allele of the microsatellite locus were 93.7 and 90.0% in Black Pied and Ayrshire breeds, respectively. In Gorbatov Red breed of dairy type with good beef qualities and low milk-fat yield, lower level of heterozygosity for PRL gene was demonstrated compared to Ayrshire and Black Pied breeds with high milk-fat yield. In three cattle breeds, higher mean estimate of polymorphism information content of PCR-RFLP in exon 3 (PIC = 0.21) was revealed compared with the same estimate (PIC = 0.09) for the microsatellite locus variability in the regulatory region of the PRL gene. Characteristics of allele B distribution of the PRL gene in the representatives of the Bovidae family are considered.  相似文献   
9.
Complexes of water soluble proteins (albumins) were investigated in three cultivarsof Phaseolus vulgaris, viz: Yeltruská Saxa, Vainica Saavegra B, and Krupnaya sakharnaya. The first two cultivars exhibit haemagglutinating activity against rabbit erythrocytes, but have different elution profiles on Sephadex G-100. Their individual peaks have a different subunit composition, as revealed by SDS gel electrophoresis, as well as a different immunoelectrophoretic pattern, although proteins I and II of the specificity Veltruská Saxa are present in both cultivars. The cultivar Krupnaya sakharnaya expressively differs from the preceding lectin cultivars; it has no erythroagglutinating activity, its albumin complex has a high-molecular component, absent in the preceding ones, and has no lectin peak in the region of molecular mass of 100 000 to 200 000. Immunoelectrophoresis gave no evidence of protein I and II of the specificity Veltruská Saxa.  相似文献   
10.
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