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The genetic contribution of 51 broodstock, comprising 29 females and 22 males, reared at Hiroshima City Marine Products Promotion Center for the production of stocked black sea bream was monitored during two consecutive years using seven microsatellite DNA loci. The high discrimination ability of these markers was reflected in the polymorphic identification content (PIC=0.831), the exclusion probability (Q≈1), and the low probability of identity index (I=3.635−10). The total number of breeders contributing to the mating process was estimated at 32 (62.7%) in 2000 and 30 (58.8%) in 2001. On pedigree reconstruction, 69.3% of the offspring were successfully assigned to a single broodstock pair. Loss of alleles accounted for 16.9% during seed production; nevertheless, 90.9% of males and 69.0% of females participated in the mating process. Based on microsatellite genetic tagging, 58.9% of the fish sampled during the two months after release were identified as hatchery stock, presenting no significant differences from wild conspecifics in either fork length or body weight.  相似文献   
13.
ABSTRACT:   Mottled amago salmon Oncorhynchus masou ishikawe with both yellow- and dark-pigmented skin occurred together with typical albino individuals in a commercial farm. Out of 12 mottled fish examined by DNA content flow-cytometry and erythrocytic nucleus size, three were diploid, eight were haploid-diploid mosaic and one was diploid-triploid mosaic. This fact indicates that the mottled coloration might link to polyploid mosaicism. Genotype of diploid and non-diploid cells at the albino locus was estimated in nine mature mottled fish by observing the frequency of wild-type and albino progeny when mating to homozygous albino ( aa ). One diploid and three haploid-diploid mosaic mottled fish were presumed to have mosaic genotype with both hemizygous ' a ' and heterozygous ' Aa ' cells ( a/Aa ), because the segregation ratio between two phenotypes was 1 : 1. Three other haploid-diploid mosaic fish were presumed to have mosaic genotype with both hemizygous ' a ' and homozygous ' AA ' cells ( a/AA ), because of exclusive occurrence of wild-type phenotype in the progeny. The diploid-triploid mosaic mottled fish was presumed to have mosaic genotypes ' aa / AAA ', ' aa/AAa ' or ' aa / Aaa ', because this fish yielded only albino progeny. One diploid mottled fish produced both two phenotypes but albino embryos appeared with much more frequency than the expectation, when assuming the genotype ' Aa '. Thus, this fish was considered to have mosaic genotype ' Aa/aa '.  相似文献   
14.
When 8-week-old BALB/c mice were sensitized with two intramuscular injections of Toxoplasma lysate antigen (TLA) at 2 week interval, the numbers of sIg(+), Thy-1,2(+), Lyt-1,2(+) Lyt-2,2(+), and Asialo GM1(ASGM1)(+) cells in the spleen, liver and peripheral blood increased by 2 to 4 times over those found in unsensitized mice of the same age. When TLA-sensitized and unsensitized mice were infected with Babesia, 4 of 10 (40%) of the TLA-sensitized mice survived infection, while none of the unsensitized control mice lived longer than 14 days after Babesia infection. By contrast, sensitization of nude mice with TLA had no effect on survival, and mice did not live more than 12 days. The number of thymic Thy-1,2(+) cells decreased in TLA-sensitized and unsensitized BALB/c mice by almost 80% within 10 days after infection (AI). During the same time, the numbers of B cells, T cells, and NK cells increased in the spleen, liver and peripheral blood of both sensitized and unsensitized mice. Especially notable were increases in numbers of Lyt-2,2(+) cells in the spleen and blood and increases in numbers of NK cells in the spleen, liver and blood in both TLA-sensitized and unsensitized mice. When spleen cells from TLA-sensitized and unsensitized mice were cultured in the presence or absence of TLA for 6 days, assays for cytotoxicity using NK-insensitive P-815 target cells and NK-sensitive YAC-1 target cells demonstrated higher rates of cytotoxicity in cultures of TLA-sensitized spleen cells.  相似文献   
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An in vitro study in which isolated prothoracic glands of the Bombyx silkworm were cultured has provided definite evidence that the prothoracic gland is the site where molting hormone is synthesized. The hormone behaved very similarly to free ecdysone on thin-layer chromatography. Analysis by liquid chromatography and mass fragmentography revealed that the hormone is identical with alpha-ecdysone.  相似文献   
17.
The high-temperature superconducting cuprate La(2-x)Sr(x)CuO(4) (LSCO) shows several phases ranging from antiferromagnetic insulator to metal with increasing hole doping. To understand how the nature of the hole state evolves with doping, we have carried out high-resolution Compton scattering measurements at room temperature together with first-principles electronic structure computations on a series of LSCO single crystals in which the hole doping level varies from the underdoped (UD) to the overdoped (OD) regime. Holes in the UD system are found to primarily populate the O 2p(x)/p(y) orbitals. In contrast, the character of holes in the OD system is very different in that these holes mostly enter Cu d orbitals. High-resolution Compton scattering provides a bulk-sensitive method for imaging the orbital character of dopants in complex materials.  相似文献   
18.
Phytate-removed deamidated soybean globulins were prepared using ion-exchange resins to provide them with a functional property to enhance calcium absorption in the body. The phosphorus level was reduced from 45 to 20 micromol/g using 0.05 g/mL of AE-4, an anion-exchange resin with a (2-hydroxyethyl)dimethylammonium group, in 0.2% soybean globulin solution for 1 h at 4 degrees C, and 90-92% of the phosphorus in defatted soybeans could be removed. As for deamidation, CE-4, a cation-exchange resin of the carboxylate type, showed a much higher deamidation activity than CE-1 and CE-2, cation-exchange resins of the sulfonate type. No peptide bond hydrolysis was observed for any cation-exchange resin treated at 4 degrees C. There was no significant difference in the amount of acid amide deamidated at temperatures between 4 and 50 degrees C. The deamidation level was able to increase to 73% using 0.10 g/mL of CE-4 in a 0.2% soybean globulin solution for 6 h at 4 degrees C. The amount of calcium bound to the soybean globulins decreased with removal of the phytate but increased with deamidation.  相似文献   
19.
The immunogenicity and safety of an attenuated Bordetella bronchiseptica vaccine for swine atrophic rhinitis (AR) was evaluated in 22 hysterectomy-produced, colostrum-deprived pigs and 18 conventional pigs. None of 8 pigs inoculated at 7 days of age intranasally with greater than or equal to 3 X 10(5) colony-forming units (CFU) of vaccinal strain/pig and 2 of 5 pigs inoculated at 7 days of age intranasally with 3 X 10(4) CFU of the vaccinal strain/pig developed AR after intranasal challenge exposure with a virulent strain at postinoculation week (PIW) 3. The remaining 3 vaccinated pigs and 4 nonvaccinated pigs developed AR. Thirteen pigs were inoculated intranasally with 3 X 10(6) to 3 X 10(9) CFU of the vaccinal strain at 7 days of age. At PIW 12, the pigs were killed and necropsied. None of the pigs had clinical signs of AR and/or pneumonia. Virulence was studied by transmission of vaccinal strain through 3 serial growing passages on the nasal mucosa of a litter of hysterectomy-produced colostrum-deprived pigs. Inoculum (nasal swab samples from 2 pigs 4 days after inoculation with 10(8) CFU of vaccinal strain at 5 days of age) was inoculated into the nasal cavity of 2 nonvaccinated pigs. This procedure was repeated 3 times. After the 1st passage, the vaccinal strain was recovered on postinoculation day 4, but after postinoculation day 4, the vaccinal strain was not recovered until the end of the 3rd passage. Turbinate atrophy or pneumonia was not recognized in these inoculated pigs. The vaccinal strain provided immunogenicity without ill effects.  相似文献   
20.
In a yeast two-hybrid screening test for tobacco proteins that interact with TMV replicase using the helicase (H) domain as bait, a cDNA clone was selected that encodes a polyamine biosynthetic enzyme, arginine decarboxylase (ADC). In yeast cells, the C-terminal internal region of ADC interacted with the H domain. This observation was confirmed in vitro by far-Western blotting. Inhibition of the binding between the H domain and the IRnHEL (I region and N-terminus of helicase domain) region by ADC using a yeast three-hybrid assay suggested possible interference of the heterodimerization of 126K and 183K by ADC.The nucleotide sequence data of pADCF reported in this study is available in the DDBJ/EMBL/GenBank databases under accession number AB110952  相似文献   
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