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31.
Hyesuck An Mi‐Jung Kim Kwangjae Park Keechae Cho Bongseong Bae Jaewoo Kim Jeong‐In Myeong 《Journal of the World Aquaculture Society》2012,43(1):73-83
The Korean rockfish, Sebastes schlegeli, is a valuable and intensively exploited species in Korea. We discuss the genetic diversity and genetic structure of four Korean rockfish populations using eight microsatellite loci. In total, 161 different alleles from 138 individuals were observed. Average allele number per locus ranged from 2.5 to 23 and allelic richness varied from 13.38 to 14.63 within a population. Despite a long history of stocking practices, we found very high levels of polymorphism (mean heterozygosity = 0.810), which is comparable to other congeneric species. No significant difference in genetic diversity and molecular genetic variance (FST and RST) was observed among four local samples (P > 0.1). Little indication of contemporary inbreeding (FIS= 0.051) or population structure (K = 1) was detected. This absence of differentiation may reflect high levels of gene flow along the coast of Korea. Our study demonstrates that rockfish in Korea should be managed as a single unit. Currently, the species does not appear to be genetically threatened, but the potential for a rapid loss of genetic diversity remains. This information on the genetic characteristics of Korean rockfish populations has important implications for fisheries management and conservation efforts, and will aid in the sustainable exploitation of the fishing resources and the preservation of biodiversity. 相似文献
32.
Summary Fifty four hybrid plants between Elymus canadensis and Psathyrostachys juncea were obtained by handpollination and embryo culture. The average cross compatibility between both species was 31.2 percent. One amphiploid plant was induced by colchicine treatment. The hybrid and amphiploid plants resembled P. juncea in appearance but showed a higher plant height and dry matter yield than the parents. The hybrids showed extremely low pollen stainability and were completely sterile. With the exception of one plant (2n=3x+1=22), all hybrid plants were allotriploids (SHN, 2n=3x=21). The amphiploid plant (SSHHNN, 2n=6x=42) showed 58.9% pollen stainability and 11.6% seed fertility.Mean chromosome associations of the hybrids and amphiploid at metaphase I were 0.02IV+0.06III+2.03II+16.91I and 0.07III+18.00II+5.85I, respectively. Lagging chromosomes, chromosome bridges, abnormal cytokinesis, and micronuclei were occasionally observed at the anaphase, telophase, or tetrad stage. 相似文献
33.
Park BS Kim JR Lee SE Kim KS Takeoka GR Ahn YJ Kim JH 《Journal of agricultural and food chemistry》2005,53(4):1152-1157
The growth-inhibiting activity of anthraquinone-2-carboxylic acid and lapachol identified in the inner bark of taheebo, Tabebuia impetiginosa, toward 10 human intestinal bacteria was evaluated by using a paper disk diffusion bioassay and compared to those of seven lapachol congeners (1,4-naphthoquinone, naphthazarin, menadione, lawsone, plumbagin, juglone, and dichlone) as well as two commercially available antibiotics, chloramphenicol and tetracycline. Anthraquinone-2-carboxylic acid exhibited very strong growth inhibition of Clostridium paraputrificum at 1 microg/disk while 100 microg/disk of lapachol was needed for moderate growth inhibition of the same organism. These two isolates exhibited weak inhibition of Clostridium perfringens and Escherichia coli at 100 microg/disk while no adverse effects were observed on the growth of Bifidobacterium adolescentis, Bifidobacterium bifidum, Bifidobacterium infantis, Lactobacillus acidophilus, and Lactobacillus casei at 1000 microg/disk. Structure-activity relationships indicate that a methyl group in the C-2 position of 1,4-naphthoquinone derivatives might play an important role in antibacterial activity. 相似文献
34.
35.
Measurements of the equation of state of deuterium at the fluid insulator-metal transition 总被引:1,自引:0,他引:1
GW Collins Da Silva LB P Celliers DM Gold ME Foord RJ Wallace A Ng SV Weber KS Budil R Cauble 《Science (New York, N.Y.)》1998,281(5380):1178-1181
A high-intensity laser was used to shock-compress liquid deuterium to pressures from 22 to 340 gigapascals. In this regime deuterium is predicted to transform from an insulating molecular fluid to an atomic metallic fluid. Shock densities and pressures, determined by radiography, revealed an increase in compressibility near 100 gigapascals indicative of such a transition. Velocity interferometry measurements, obtained by reflecting a laser probe directly off the shock front in flight, demonstrated that deuterium shocked above 55 gigapascals has an electrical conductivity characteristic of a liquid metal and independently confirmed the radiography. 相似文献
36.
Protective effect of anthocyanins from black soybean seed coats on UVB-induced apoptotic cell death in vitro and in vivo 总被引:1,自引:0,他引:1
Tsoyi K Park HB Kim YM Chung JI Shin SC Shim HJ Lee WS Seo HG Lee JH Chang KC Kim HJ 《Journal of agricultural and food chemistry》2008,56(22):10600-10605
UVB radiation proves to be one of the most relevant environmental risks because of its hazardous effects, such as premature skin aging and especially skin photocarcinogenesis. Anthocyanins, water-soluble pigments present in plants, are known to be powerful antioxidants that help protect plants from UV damage. In this study, we aimed at investigating the protective effect of anthocyanins from black soybean [Glycine max (L.) Merr] seed coats on UVB-induced apoptosis, and furthermore, we investigated the molecular mechanism responsible for regulation of apoptosis in vitro and in vivo. Pretreatment with anthocyanins reduced UVB-induced reactive oxygen species levels and inhibited UVB-induced apoptotic cell death through the prevention of caspase-3 pathway activation and reduction of proapoptotic Bax protein levels. UVB irradiation induced apoptotic cell death, which was inhibited by topical application of anthocyanins in hairless mice. It is concluded that anthocyanins from the seed coat of black soybeans may be useful compounds to modulate UVB-induced photoaging. 相似文献
37.
Eun Young Park Byung‐Kee Baik Stephen Machado Hero T. Gollany E. Patrick Fuerst 《Cereal Chemistry》2015,92(3):332-338
The effects of no‐till versus conventional farming practices were evaluated on soft wheat functional and nutritional characteristics, including kernel physical properties, whole wheat composition, antioxidant activity, and end‐product quality. Soft white winter wheat cultivar ORCF 102 was evaluated over a two‐year period from three long‐term replicated no‐till versus conventional tillage studies in Oregon. Wheat from the no‐till cropping systems generally had greater test weight, kernel diameter, and kernel weight and had softer kernels compared with wheat from the conventional tillage systems. Compared with the conventional systems, no‐till whole wheat flour had lower protein and SDS sedimentation volume. Ash content as well as most minerals measured (calcium, copper, iron, magnesium, and zinc), except for manganese and phosphorus, were generally slightly lower in no‐till than in conventional wheat. Whole wheat flour from the no‐till cropping systems generally had slightly lower total phenolic content and total antioxidant capacity. Milling properties, including flour yield, break flour yield, and mill score, were not affected by tillage systems. Refined flour from no‐till systems had lower protein, SDS sedimentation volume, and lactic acid and sucrose solvent retention capacities compared with flour from conventional tillage. No‐till wheat generally had greater sugar‐snap cookie diameter than conventionally tilled wheat. In conclusion, no‐till soft white winter wheat generally had slightly reduced nutritional properties (protein, ash, most minerals, and total antioxidant content) compared with wheat from conventionally tilled systems, and it had equivalent or sometimes superior functional properties for baking cookie‐type products. 相似文献
38.
Y. H. Jang S. J. Lee J. G. Lim H. S. Lee T. J. Kim J. H. Park B. H. Chung N. H. Choe 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(2):177-181
Salmonellosis is an important zoonotic disease that affects both people and animals. The incidence of reptile-associated salmonellosis has increased in Western countries due to the increasing popularity of reptiles as pets. In Korea, where reptiles are not popular as pets, many zoos offer programs in which people have contact with animals, including reptiles. So, we determined the rate of Salmonella spp. infection in animals by taking anal swabs from 294 animals at Seoul Grand Park. Salmonella spp. were isolated from 14 of 46 reptiles (30.4%), 1 of 15 birds (6.7%) and 2 of 233 mammals (0.9%). These findings indicate that vigilance is required for determining the presence of zoonotic pathogen infections in zoo animals and contamination of animal facilities to prevent human infection with zoonotic diseases from zoo facilities and animal exhibitions. In addition, prevention of human infection requires proper education about personal hygiene. 相似文献
39.
Kim HH Kwon HJ Ryu YB Chang JS Cho KO Hosmillo MD Rho MC Park SJ Lee WS 《Research in veterinary science》2012,92(2):320-323
In vitro anti-rotavirus activity of Alpinia katsumadai (AK) extracts were evaluated against bovine G8P[7] and porcine G5P[7] rotaviruses in two different assay strategies, a mixed treatment assay and a post treatment assay. In the mixed treatment assay, six AK extracts [AK-1 (EtOH extract), AK-3 (H(2)O layer), AK-5 (40% methanol fraction), and AK-9-11 (H(2)O extract, polysaccharide fraction, supernatant fraction)] exhibited inhibitory activities against G5P[7] rotavirus with the EC(50) values ranging from 0.7±0.4 to 33.7±6.5 μg/mL. Extracts AK-1, AK-3, and AK-5 inhibited rotavirus infection against G8P[7] rotavirus, the with EC(50) values of 8.4±2.2 μg/mL, 6.5±0.8 μg/mL and 8.4±5.0 μg/mL, respectively. By hemagglutination inhibition (HI) assay, six AK extracts completely inhibited viral adsorption onto human RBCs in both strains of rotaviruses at less than 11 μg/mL. However, in the post treatment assay, there was no anti activity shown against both strains of rotaviruses. As a result, six AK extracts were attributed mainly to having a strong interaction with hemagglutinin protein on the outer surface of rotavirus, resulting to blockage of viral adsorption. 相似文献
40.
Park M 《Journal of the American Veterinary Medical Association》2007,231(2):196-7; author reply 197-8