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A method based on morphological characters is proposed to evaluate biological diversity of a sockeye salmon population. In all samples, morphological diversity of males is greater than that of females. In addition, the inter-annual dynamics determined on the basis of separate morphological characters differs in individuals of different sex. The necessity of studying biological diversity for preserving population homeostasis is also considered.  相似文献   
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Results from the 1993–2004 genetic monitoring of pink salmon populations reproducing in the rivers of Tauy Bay on the Sea of Okhotsk are analyzed. A statistically significant heterogeneity of samples as determined by gene frequencies is found only in the pink salmon generations of even years. The genetic differentiation of samples from even years (GST = 1.39 ± 0.41) is higher than that of odd years (GST = 0.740.09). The pattern for the indicator of genetic variability (heterozygosity) is exactly the opposite (0.076 ± 0.02564 vs. 0.8760 ± 0.01950). Consequently, the lower-heterozygosity samples of lines from even years are on average more genetically distinct than the analogous indicator for odd years. In addition, the interpopulation ratio in the general value of genetic diversity is almost always smaller than both the intraannual and interannual ratios, leading to a low level of interpopulation genetic differences. Cluster analysis reveals that most 2001–2004 samples are grouped separately from samples collected prior to 2000. In our opinion, the reason for this could be the turnover of a numerically dominant generation of northern Sea of Okhtosk pink salmon and the change in gene frequencies accompanying it.  相似文献   
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The population genetic structure of yellowfin sole inhabiting the northern part of the Okhotsk Sea has been investigated. The genetic heterogeneity of samples collected in geographically remote areas of Taui Bay was determined. The value of genetic differentiation (G ST = 2.39%) in the studied samples was slightly lower than in those from the Bering Sea (G ST = 4.25%) (Grant et al., 1983).  相似文献   
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The genetic structure of a small sockeye salmon population from the Ola River (Tauyskaya Inlet, the Okhotsk Sea) was shown to exhibit high heterogeneity. Significant differences of LDH-B2*and ALAT-2*gene frequencies were detected not only among samples within the spawner and juvenile groups but also between spawners and juveniles as a whole. The average heterozygosity of sockeye salmon from the Ola River was considerably lower than the corresponding values for other Asian populations. The Ola sockeye salmon is genetically similar to the population from the Pakhach River of the northwestern Kamchatka Peninsula but different from other Kamchatka populations and the Okhota River population. A hypothesis explaining the genetic differentiation of Asian sockeye populations is advanced.  相似文献   
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Genetic parameters of pink salmon introduced into the White Sea basin in 1985 and 1998 were compared to the corresponding parameters of the donor population from the Ola River (Magadan oblast). The detected genetic differences indicate that colonization of a new area is accompanied by impoverishment of the gene pool of the native population. This effect was particularly marked in the odd-year broodline of pink salmon introduced in 1985. The probable causes of these genetic changes are discussed.  相似文献   
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Antirestriction proteins ArdA and ArdB are specific inhibitors of type I restriction-modification enzymes. The ardA and yfeB (ardB) genes were cloned from the transmissible plasmid R64 in the pUC18 and pZE21 vectors. The R64 ArdA and ArdB proteins were shown to inhibit only restriction activity of the type I restriction-modification enzyme (EcoKI) in Escherichia coli K12 cells. In contrast to ArdA, ArdB inhibited EcoKI restriction activity only at a high intracellular concentration. Antirestriction activity of ArdB did not depend on the ClpXP protease. The yfeB (ardB) gene of the R64 plasmid is transcribed from a weak promoter located upstream of yfeA.  相似文献   
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Porphobilinogen deaminase (PBGD) is a key enzyme of the heme biosynthetic pathway. Defects in the PBGD gene lead to an autosomal dominant disease, acute intermittent porphyria (AIP). Almost all AIP patients with rare exceptions are heterozygous for the defective gene. To date, at least 160 different mutations causing AIP are identified. Extensive investigations along this line are conducted in many countries of the world. In Russia these studies had not been hitherto performed. Here we report the results of molecular genetic examination of four Russian patients with AIP diagnosed from clinical symptoms. By direct sequencing of the PBGD gene or the corresponding cDNA, we have detected four mutations, three of which were not previously encountered in the world population. These are TAAG deletion in intron 7 between positions +2 and +5 (IVS7 2–5 delTAAG); T deletion in the initiation codon ATG of exon 3, and the G for C replacement at position –1 of intron 5 (IVS5 as –1 G–C), which disrupts splicing. In addition, in one female patient, a known deletion CT in codon 68 was revealed. In two patients, expression of PBGD gene alleles was significantly disproportional, so that normal mRNA prevailed in one case and mutant mRNA of nonerythroid type in the other. Deletion in intron 7 was easily detectable due to the formation of a heteroduplex fragment with abnormal electrophoretic mobility directly in PCR. This simple heteroduplex analysis allowed us to exclude AIP carriage in son and daughter of a female patient with the genetic defect.  相似文献   
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