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61.
Goats (Capra hircus) were domesticated in the Fertile Crescent and propagated all over the world. The Silk Road through the Eurasian Steppe belt is a possible propagation route for domestic goats to Central Asia. Kazakhstan is in close geographical proximity to domestication centers and covers the majority of the Eurasian Steppe belt. In this study, we examined the genetic diversity and phylogeographic structure of Kazakhstani goats. The mtDNA sequences of 141 Kazakhstani goats were categorized into haplogroups A, C, and D, of which haplogroup A was predominant (97%), whereas haplogroups C and D were detected at low frequencies (1.4% each). The Kazakhstani haplotypes C were thzen categorized into Asian mtDNA type. Sequence analysis of the SRY gene on the Y‐chromosome in 67 male Kazakhstani goats revealed two haplotypes: Y1A (64%) and Y2A (36%). Analysis of the distribution of mtDNA haplogroups and SRY haplotypes from Eurasia and Africa demonstrated genetic similarity among animals from Kazakhstan, Mongolia, and Northwest China located on the Eurasian Steppe belt. These phylogeographic results suggested that the Eurasian Steppe belt was an important propagation route for goats to Central Asia.  相似文献   
62.
In turtles, the epithelia lining the upper and lower chambers of the nasal cavity project axons to the ventral and dorsal parts of the olfactory bulbs, respectively. In a semi-aquatic soft-shelled turtle, Pelodiscus sinensis, more than 1,000 odorant receptor genes have been found, but it is not known where they are expressed. In this study, we aimed to clarify the distribution of cells expressing these genes in the olfactory organs of soft-shelled turtles. Immunoreactions for the Gαolf, the α subunit of G protein coupled to the odorant receptors, were detected on the surface of epithelia lining both the upper and lower chambers of the nasal cavity. The receptor cells in the epithelium of both chambers possessed cilia on the tip of their dendrites, whereas microvillous, non-ciliated, receptor cells were not found. These data suggest that the odorant receptor genes are expressed by the ciliated receptor cells in the upper and lower chamber epithelia. Precise location of the vomeronasal epithelium is not known at present.  相似文献   
63.
To produce 5-reductase inhibitory compounds, resveratrol was enzymatically oxidized in a horseradish peroxidase (HRP)/H2O2 system. Ethyl acetate extract of the oxidation products showed strong 5-reductase inhibitory activity with 10%–15% organic solvents in the system, whereas without organic solvent little inhibitory activity was exhibited. The optimum pH of enzymatic oxidation for acquisition of the inhibitory activity was 4.5. The inhibitory compounds were isolated and identified as resveratroltrans-dehydrodimer and resveratrolcis-dehydrodimer by comparing with published nuclear magnetic resonance data. The two resveratrol dehydrodimers have stronger inhibitory activity than natural resveratrol dimers and trimers found inShorea species.  相似文献   
64.
In northern Lao People’s Democratic Republic, rising human population has drastically reduced the fallow period of slash-and-burn agriculture which has led to a considerable decrease in the carbon stock in these communities. We estimated chronosequential changes in the communities' carbon stocks, and established the relationship between the fallow period and fallow-period-average carbon stocks in three carbon pools of bamboo-dominated communities in hilly areas of the Luang Prabang Province, northern Lao People’s Democratic Republic. Based on measurements by destructive sampling, we devised a model and root-to-shoot ratios for estimating bamboo biomass. In six secondary plant communities established after slash-and-burn cropping, we estimated community biomass using the above model and others, and measured deadwood and litter stocks. The communities’ biomass and deadwood significantly increased with time after the last cropping and the former reached about 100 Mg ha−1 after 15 years, whereas litter stocks did not show significant trends over time. Extending the fallow period from 2 to 5 years would increase fallow-period-average carbon stock from 14.2 to 25.1 Mg C ha−1. The overstory height was significantly correlated with biomass, deadwood, and litter carbon stocks of these communities. Based on our findings, changes in a community’s carbon stocks can be estimated using the changes in overstory height, which should be taken into account in future studies to reduce uncertainty in estimating carbon stocks in tropical ecosystems.  相似文献   
65.
Volatile organic compounds (VOCs) from wood and their effects on artifacts are of intense interest to museum staff who must strictly manage the preservation environment. In this study, the causal substances of deterioration were inferred by comparison with laser Raman (LR) spectra of deterioration products. The artifact samples were deteriorated using VOCs from woods (WV test), and using specific substances that occur in wood VOCs (SV test). The deteriorated samples were analyzed by LR spectroscopy and the results of the WV and SV tests were compared. Hinokitiol and acetic acid were found to be two of the main causal substances of deterioration in western red cedar. Deterioration of iron and copper by spruce did not appear to be caused by acetic acid, as is generally assumed, but by some other unknown compound(s). Sensitivity to wood-based VOC components depended on the type of artifact. In western red cedar, mitsudasou (litharge) was very sensitive to acetic acid, while other artifacts were sensitive to hinokitiol. The LR method used in this study is very useful for the inference of causal substances of deterioration based on the detection of small amounts of deteriorated products such as those generated by deterioration due to wood VOCs. Part of this article was presented at the 25th Annual Meeting of the Japan Society for the Conservation of Cultural Property, Kyoto, June 2003  相似文献   
66.
The possibility of persorption of bovine serum albumin (BSA) molecules from mucous epithelial cells and its mechanism were investigated in rats orally pre-immunized by BSA for 14 consecutive days. In the small and large intestines, both the BSA antigen (BSA-Ag) and its specific antibody (SpAb) were absorbed by the epithelial cells at the late apoptotic stage (ApoEp), and were subsequently transcytosed by membranes of the small vesicles. The basal cytoplasms containing highly-concentrated BSA-Ag and SpAb were occasionally fragmented into small cytoplasmic droplets that were secreted into the lamina propria. In Peyer's patches, both BSA-Ag and SpAb were more actively absorbed and transcytosed toward the dome area by the ApoEp of the dome apex than by the M cells. BSA-Ag and SpAb were finally persorbed into the portal blood and lymph, but were never secreted into the bile. They were also engulfed by macrophage-like cells in the villous lamina propria, mesenteric lymph node and spleen, and by hepatocytes in the liver. These findings suggest that sensitized soluble luminal antigens are taken up by ApoEp in the small intestine and are finally persorbed into the peripheral blood. The uptake of luminal antigen might be mediated by its luminal SpAb.  相似文献   
67.
In our studies of the chain-breaking antioxidant mechanism of natural phenols in food components, ferulic acid, a phenolic acid widely distributed in edible plants, especially grain, was investigated. The radical oxidation reaction of a large amount of ethyl linoleate in the presence of the methyl ester of ferulic acid produced four types of peroxides as radical termination products. The isolation and structure determination of the peroxides revealed that they had tricyclic structures which consisted of ethyl linoleate, methyl ferulate, and molecular oxygen. Based on the formation pathway of the products, a radical scavenging reaction occurred at the 3'-position of the ferulate radical with the four types of peroxyl radicals of ethyl linoleate. The produced peroxides subsequently underwent intramolecular Diels-Alder reaction to afford stable tricyclic peroxides.  相似文献   
68.
We developed molecular markers for discrimination of white and blue flower color in Japanese gentian plants. White-flowered gentians can be classified into two types, based on genetic and physiological features. One type includes four allelic variations (gtmyb3-1, gtmyb3-2, gtmyb3-3, and gtmyb3-4) of an anthocyanin biosynthetic regulator gene (GtMYB3), distinguished by three PCR-based molecular markers. The other type contains a newly identified inactive allele (ans1) of the anthocyanidin synthase (ANS) gene with a premature stop codon generated from a 4-bp deletion in the second exon. The ans1 allele was distinguished from the active ANS allele by a cleaved amplified polymorphism sequence (CAPS) marker. The genotypes of 12 white-flowered gentian cultivars/lines could be identified and classified as either ans1 or gtmyb3 using these four molecular markers. No white-flowered gentians contained ans1 and gtmyb3 alleles simultaneously. The mutated ANS gene co-segregated with white flower color in an F2 population, demonstrating that the CAPS marker is useful to discriminate between white and blue flowers in gentian. Markers to discriminate flower color in Japanese gentian will be useful for early selection of progeny and for breeding management.  相似文献   
69.
70.
A case was discovered where the embryo transfer (ET) calf had been infected with bovine leukemia virus (BLV) from the recipient cow. The embryo was transferred from the BLV-uninfected donor cow to the recipient cow. However, the BLV test had not been performed to the recipient cow before ET was performed. The ET calf was raised in a calf hatch from birth to 1-month old and was given the recipient cow's colostrum and milk artificially. The ET calf was raised with the two other calves from a 1-month old to a 6-month old. The BLV test was performed to the ET calf by agar gel precipitation (AGP) and passive haemagglutination (PHA) assay when the ET calf was 6 months old. Because the ET calf was positive, the BLV test was performed to the recipient cow, the two other calves raised with the ET calf and the two dams of the two other calves. Because the recipient cow only was positive at the time of the first test, we judged that the ET calf had been infected with BLV from the recipient cow. The importance of the BLV test being carried out on the recipient cow for the prevention of enzootic bovine leukemia in a case of ET was recognised.  相似文献   
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