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1.
In this paper the recent population changes of the Wild Boar in different European countries is analysed through the study of hunting statistics. A simultaneous increase in numbers is observed throughout the whole area during the period 1965–1975. From 1975 onwards the population stabilizes itself apart from in peripheral areas like Finland. Potentially favourable factors which play a part in this process are discussed and certain reproductive and dispersive characteristics which favour its invasive behaviour are discussed. 相似文献
2.
Experiments on curarized carp showed that neurons of the vagal lobe of the medulla respond to stimulation not only of the mouth and gills, but also of chemoreceptors of the skin of the head. The vagal lobe was shown to contain considerably fewer neurons responding selectively to stimulation of the skin than neurons responding to stimulation of the mouth or gills. Differences were found between responses of neurons to a natural food stimulus (extract from a fish food product) and to solutions of hydrochloric acid and common salt. The different roles of the vagal and facial lobes in the processing of impulsation from skin chemoreceptors is demonstrated.A. A. Zhdanov Leningrad State University. Translated from Neirofiziologiya, Vol. 12, No. 4, pp. 397–404, July–August, 1980. 相似文献
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To solve some systematic questions as well as to study genetic variability and evolutionary relationships in two groups of
fish belonging to the Mugilid (Mugilidae) and Cyprinid (Cyprinidae) families, we have used restriction fragment length polymorphism
analysis of mitochondrial DNA (mtDNA) fragments amplified in polymerase chain reaction. The analysis of three mtDNA fragments
of 7220 bp total length of six Mugilid species has shown that Mediterranean Liza aurata, L. ramada, L. saliens, and Chelon labrosus form a common cluster, L. aurata and C. labrosus being the closest relatives, whereas L. haematocheilus (syn. C. haematocheilus) of the Sea of Japan forms a sister group to the Mediterranean cluster. It was found that Chelon and Liza genera are paraphyletic, and therefore their division into two genera is unnatural and they should be synonymized. According
to priority, Liza species should be ascribed to Chelon genus. Mugil cephalus is the most distant compared to the rest of the species studied. The level of genetic divergence between allopatric samples
of M. cephalus from the Sea of Japan and the Mediterranean Sea has proved to be very high—4.5% of nucleotide substitutions. The analysis
of four mtDNA fragments of 9340 bp total length of six Cyprinid species has shown that L. waleckii is the most genetically distant. Pseudaspius leptocephalus is a sister group to Tribolodon species. All Tribolodon species form a common cluster with T. sachalinensis as a root. The remaining species form two branches, one of which includes T. nakamurai and T. brandtii, another one combines T. hakonensis and a new form of Tribolodon revealed that is close to T. hakonensis by its mtDNA (2.4% of nucleotide substitutions). This new form might be an independent species.
Published in Russian in Biokhimiya, 2007, Vol. 72, No. 12, pp. 1651–1658. 相似文献
5.
Gemma V. White Emma V. Edgar Duncan S. Holmes Xiao Qing Lewell John Liddle Oxana Polyakova Kathrine J. Smith James H. Thorpe Ann L. Walker Yichen Wang Robert J. Young Alain Hovnanian 《Bioorganic & medicinal chemistry letters》2019,29(6):821-825
Netherton syndrome (NS) is a rare and debilitating severe autosomal recessive genetic skin disease with high mortality rates particularly in neonates. NS is caused by loss-of-function SPINK5 mutations leading to unregulated kallikrein 5 (KLK5) and kallikrein 7 (KLK7) activity. Furthermore, KLK5 inhibition has been proposed as a potential therapeutic treatment for NS. Identification of potent and selective KLK5 inhibitors would enable further exploration of the disease biology and could ultimately lead to a treatment for NS. This publication describes how fragmentation of known trypsin-like serine protease (TLSP) inhibitors resulted in the identification of a series of phenolic amidine-based KLK5 inhibitors 1. X-ray crystallography was used to find alternatives to the phenol interaction leading to identification of carbonyl analogues such as lactam 13 and benzimidazole 15. These reversible inhibitors, with selectivity over KLK1 (10–100 fold), provided novel starting points for the guided growth towards suitable tool molecules for the exploration of KLK5 biology. 相似文献
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A. V. Semina N. E. Polyakova M. A. Makhotkin V. A. Brykov 《Russian Journal of Marine Biology》2007,33(3):187-192
Three Mugilid species: Mugil cephalus (Linnaeus, 1758) and Liza haematocheila (Temminck et Schlegel, 1845; syn. Mugil soiuy, M. haematocheilus, L. soiuy, Chelon haematocheilus) from the Sea of Japan, as well as M. cephalus and Liza aurata (Risso, 1810) from the Sea of Azov were investigated on the basis of PCR-RFLP analysis of mitochondrial DNA (mtDNA) fragments, which included 12S/16S rRNA, and ND3/ND4L/ND4 genes. Among 61 individuals of three Mugilid species thirteen different haplotypes were detected. Eight and thirteen restriction endonucleases were found to be species-specific in 12S/16SrRNA and ND3/ND4L/ND4 respectively. This method may be useful for species identification. M. cephalus showed the largest genetic divergence while L. haematocheila and L. aurata were closely related and clustered together. The level of mtDNA differentiation between the two M. cephalus samples from the Sea of Japan and the Sea of Azov, i.e., nucleotide substitutions of approximately 3%, appeared to be relatively high. 相似文献
8.
Bulatnikov IG Polyakova OV Asryants RA Nagradova NK Muronetz VI 《Journal of Protein Chemistry》1999,18(1):79-87
The binding of denatured B. stearothermophilus D-glyceraldehyde-3-phosphate dehydrogenase (GAPDH) to the E. coli chaperonin GroEL was investigated in two systems: (1) GroEL immobilized on Sepharose via a single subunit was titrated with urea-denatured soluble GAPDH and (2) a Sepharose-bound denatured GAPDH monomer was titrated with soluble GroEL. Similar apparent K
D values for the complex GroEL·GAPDH were obtained in both cases (0.04 and 0.03 M, respectively), the stoichiometry being 1.0 mol chaperonin per GAPDH subunit in the system with the immobilized GroEL and 0.2 mol chaperonin per Sepharose-bound GAPDH monomer. Addition of GroEL and Mg·ATP to a reactivation mixture increased the yield of reactivation of both E. coli and B. stearothermophilus GAPDHs. Incubation of the Sepharose-bound catalytically active tetrameric and dimeric GAPDH forms with the protein fraction of a wild-type E. coli cell extract resulted in the binding of GroEL to the dimer and no interaction with the tetrameric form. These data suggest that GroEL may be capable of interacting with the interdimeric contact regions of the folded GAPDH dimers. 相似文献
9.
Vl. A. Brykov N. Polyakova L. A. Skurikhina A. D. Kukhlevsky O. N. Kirillova D. Churikov †‡ A. I. Pudovkin A. J. Gharrett † 《Journal of fish biology》1999,55(3):617-635
Both odd- and even-year pink salmon populations were sampled during the spawning runs in Firsovka and Bakhura rivers on Sakhalin Island. Four collections of 30 fish spaced at 2-week intervals were taken from each river in 2 consecutive years. Four restriction endonucleases were used to examine 2·15% of the mitochondrial genome. Eighteen variable sites and three types of insertion defined 37 haplotypes among 449 fish. Heterogeneity tests showed highly significant differences among temporal collections taken in the odd year from Bakhura River, and no significant differences among temporal collections from the other three spawning runs. However, probabilities of homogeneity among temporal collections were low in all tests, and an integral estimate of the probability of homogeneity for the total set of tests was less than 0·001, indicating highly significant overall temporal heterogeneity. Analysis of molecular variance (AMOVA), revealed that a small portion of the variance was distributed among temporal collections, and small φST values that differed significantly from zero only in the odd-year population in Bakhura River. Temporal differences in spawning are probably adapative, and allow greater productivity in areas of high spawning densities. 相似文献
10.
Vasil'ev E. V. Roumiantsev P. O. Saenko V. A. Il'in A. A. Polyakova E. Yu. Nemtsova M. V. Zaletayev D. V. 《Molecular Biology》2004,38(4):538-548
Rearrangements of the protooncogene RET (RET/PTC) and somatic mutations of the gene BRAF are the most common events in the etiopathogenesis of papillary thyroid carcinoma (PTC). The rates of RET/PTC rearrangements and BRAF mutations in different nodular formations of the thyroid gland (TG) have been estimated. Comparative expression analysis of the extracellular (EC) and tyrosine kinase (TK) domains of RET has shown that 14% (12 out of 85) of PTC cases are RET/PTC-positive, including one RFP/RET-, two RET/PTC3-, and seven RET/PTC1-positive tumors, as well as two unidentified chimeric RET/PTC oncogenes. The standard T1796A transversion in the gene BRAF has been found in 60% (55 out of 91) PTC cases with the use of amplification refractory mutation system–polymerase chain reaction (ARMS–PCR). Somatic mutation G1753A and deletion del1800_1811 have been identified in PTC for the first time. The absence of the BRAF mutations in RET/PTC-positive tumors allows these two genetic defects to be regarded as alternative mechanisms of the RAS–RAF–MEK–ERK mitogen-activated protein (MAP) kinase cascade activation in PTCs. In none of the three follicular thyroid carcinomas (FTCs), 11 follicular thyroid adenomas (FTAs), and 13 nodular goiters have either BRAF mutations or RET/PTC rearrangements been found. Thus, the RET/PTC chimeric oncogenes and BRAF somatic mutations are specific markers of PTC and can be used for the preoperative diagnosis of these tumors. 相似文献