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991.
Myonsun Yoh Nobuhiro Kawakami Yasunobu Funakoshi Keishi Okada Takeshi Honda 《Microbiology and immunology》1995,39(2):157-159
Reversed passive latex agglutination (RPLA) or enzyme-linked immunosorbent assay kits with beads (Bead-ELISA) are commercially available in Japan to detect the thermostable direct hemolysin (TDH) produced by Vibrio parahaemolyticus isolates. We evaluated whether these kits can be used to assay the pathogenic toxin, TDH-related hemolysin (TRH), produced by some so-called Kanagawa phenomenon-negative V. parahaemolyticus strains isolated from patients with diarrhea. Our results showed that the two kits, RPLA and Bead-ELISA, can detect TRH, although they were originally developed for detection of TDH. This may be due to the use of polyclonal anti-TDH antisera that cross react with TRH. Although the sensitivity for TDH detection by RPLA and Bead-ELISA differed tenfold, that for TRH detection was essentially equal. The minimum concentration of TRH required for detection by the two assay kits was about 10 ng/ml. 相似文献
992.
N. Nakazono A. Kanno N. Tsutsumi A. Hirai 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,91(1):1-8
Palindromic repeated sequences (PRSs) are distributed in at least ten regions of the mitochondrial (mt) genome of rice and are, apparently, mobile. In the present study, we examined the possibility of homologous recombination via some PRSs during the course of evolution of Oryza. We first performed Southern hybridization of the DNA from 11 species (18 strains) of Oryza in order to identify the distribution of PRSs in the mitochondrial genome of Oryza. The hybridization patterns revealed genome type-specific and/or species-specific variations. We speculated that homologous recombination via some PRSs might have made a contribution to such variations. After subsequent polymerase chain reaction, Southern hybridization and sequencing, we concluded that homologous recombination mediated by two PRSs occurred in the mtDNA of Oryza after divergence of the BB genome type and the other genome types of Oryza. Evidence was obtained that some PRSs were involved in both insertion and recombination events during the evolution of Oryza. Our results indicate, therefore, that PRSs have contributed considerably to the polymorphism of Oryza mtDNAs. 相似文献
993.
K. Irifune K. Hirai J. Zheng R. Tanaka H. Morikawa 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,90(3-4):312-316
A highly repeated DNA sequence with a repeating unit of approximately 380bp was found in EcoRV digests of the total genomic DNA of Allium fistulosum. Three independent clones containing this unit were isolated, and their repeating units sequenced. These units showed more than 94% sequence homology, and the copy number was estimated to be about 2.8×106 per haploid genome. In situ hybridization, with the repeating unit as a probe, and C-banding analyses indicated that the repeated DNA sequence of A. fistulosum is closely associated with the major C-heterochromatin in the terminal regions of all 16 chromosomes at mitotic metaphase. The characters of the repeating unit are similar to those of the A. cepa unit, which is taxonomically closely related to A. fistulosum. 相似文献
994.
Establishment and Characterization of a Human Epstein-Barr Virus-Associated Gastric Carcinoma in SCID Mice 总被引:2,自引:0,他引:2 下载免费PDF全文
995.
Genomic dispersion of 28S rDNA during karyotypic evolution in the ant genusMyrmecia (Formicidae) 总被引:3,自引:0,他引:3
Hirohisa Hirai Masa-Toshi Yamamoto Robert W. Taylor Hirotami T. Imai 《Chromosoma》1996,105(3):190-196
The chromosomal localization of 28S rDNA was investigated in 16 speices of the Australian ant genus Myrmecia, with 2n numbers ranging from 4 to 76, using the fluorescence in situ hybridization method and karyographic analysis. A unique phenomenon
was observed: the number of chromosomes carrying 28S rDNA increases from 2 in species with low chromosome numbers to 19 in
species with high chromosome numbers. This is termed rDNA dispersion. Centric fission and a reciprocal translocation that
occurs in C-bands were detected as the major mechanisms involved in rDNA dispersion.
Received: 22 March 1996; in revised form: 3 June 1996 / Accepted: 4 June 1996 相似文献
996.
Marek's disease virus (MDV) showed only 0.3-0.6% homology in DNA sequence with herpesvirus of turkeys (HVT) at Tm-24.4 degrees C in spite of its antigenic similarity to the latter. Southern blot hybridization under stringent conditions showed that the homology between MDV and HVT is located in the restricted portion of these viral genomes. At Tm-49.6 degrees C, which permits the detection of homology with one base mismatch in three between the MDV and HVT DNAs, sequences with weak homology were found to be distributed over most of these viral genomes. No homology was detected between Epstein-Barr virus and either MDV or HVT DNA. 相似文献
997.
A reduced nicotinamide adenine dinucleotide phosphate (NAD(P)H)-dependent H2O2-generating activity of the rat uterus was investigated both electron cytochemically and biochemically. We tried to cytochemically demonstrate H2O2 generation from the oxidation of reduced NADH or NADPH using the cerium method. NADPH oxidation resulted in electron-dense deposits on the apical plasma membrane covering the microvilli of the surface epithelium of the lightly fixed endometrium. In control specimens incubated in a medium from which substrate was omitted, no such deposits were observed. The reduction of ferricytochrome c due to NADH oxidation was spectrophotometrically detected in the lightly fixed uterus. Absorption at 550 nm increased with the addition of NADH, but not with that of NAD. The reaction was weakened by preheating and adversely affected by the addition of superoxide dismutase, but it was not inhibited by adding 50 mM sodium azide. These results suggest that a kind of NAD(P)H oxidase, generating H2O2 via superoxide formation, may possibly be present on the apical plasma membrane of the rat endometrial epithelium. 相似文献
998.
K Hirai K Shiwaku T Tsuboi M Torii H Nishida Y Yamane 《Zeitschrift für Parasitenkunde (Berlin, Germany)》1983,69(4):489-499
Observations were made of the biological effects on infection with plerocercoids of Spirometra erinacei on normal female Snell mice, male chinese hamsters, golden hamsters, normal and hypox rats. Plerocercoid infection caused the strongest growth-promoting effect on normal Snell mice. In mice, this effect appears to be independent of strain. Chinese hamsters infected with these larvae showed similar growth. The infected normal rats and golden hamsters, however, showed a weight increase in the skeletal muscle only, while the hypox rats exhibited no effect at all. The elevation in the concentration of serum triglyceride was observed in all the animals investigated except for rats. Golden hamsters, in particular, exhibited a marked increase in the concentration of serum free fatty acids and total cholesterol. There was close correlation between the concentrations of serum triglyceride and free fatty acids, and the regression coefficient of the resulting linear regression equation for the experimentals was higher than that for the controls. This suggests that serum triglyceride results from an increased concentration of serum free fatty acids derived from stimulated lipolysis. The total cholesterol concentration in the serum decreased in chinese hamsters infected with larvae. The serum glucose concentration increased in normal Snell mice but decreased in chinese and golden hamsters. No difference in glycerol and free fatty acid concentration was observed in infected animals except for golden hamsters. 相似文献
999.
Processing of glycoprotein gB related to neutralization of Marek's disease virus and herpesvirus of turkeys 总被引:5,自引:0,他引:5
The glycoprotein gB related to neutralization of Marek's disease virus (MDV) and herpesvirus of turkeys (HVT) is composed of several glycosylated polypeptides, which were immunoprecipitated with monoclonal antibodies and rabbit antiserum cross-reactive to MDV-gB and HVT-gB, and analyzed by SDS-polyacrylamide gel electrophoresis. The present pulse-chase experiments showed that the precursor forms of MDV- and HVT-gB were glycoproteins with molecular weights of 110K to 115K (gp115/110) and 115K (gp115), respectively. These precursor forms were processed to smaller gB's (gp63 and gp50 for MDV; gp62, gp52, and gp48 for HVT), at least in part by sialylation. The proteins synthesized in the presence of tunicamycin were two polypeptides of 88K and 83K in MDV-infected cells and a 90K polypeptide in HVT-infected cells, indicating the presence of unglycosylated precursor forms of MDV- and HVT-gB. Differences between virulent and avirulent MDV's and between HVT's with and without protective activity against Marek's disease were observed in the processed forms of MDV- and HVT-gB, especially at the processing step of sialylation. 相似文献
1000.
Kazuo T. Suzuki Hiroko Tamagawa Seishiro Hirano Etsuko Kobayashi Kuniko Takahashi Nobuhiro Shimojo 《Biological trace element research》1991,28(2):109-121
Daily changes in components of breast milk with number of days of lactation after delivery were demonstrated by determining
concentrations and distributions of several elements simultaneously. Concentrations of calcium, copper, magnesium, phosphorus,
sulfur, and zinc were determined simultaneously by inductively coupled argon plasma-atomic-emission spectrometry (ICP) for
whole milk and milk fractions (skimmed milk and whey) collected from 2 to 196 d postpartum from a healthy lactating mother.
Calcium and phosphorus concentrations increased in transitional milk. With days postpartum, the other elements decreased from
the highest concentrations in colostrum milk, the modes of decrease being characteristic for each element. Distributions of
copper, iron, phosphorus, sulfur, and zinc in whey were determined on a gel-filtration column by HPLC with ICP detection (HPLC-ICP
method). Distributions of the five elements and absorbance peaks at 254 and 280 nm changed dramatically day by day at the
beginning (colostrum milk), resulting in constant distributions after 30 d (mature milk). These results suggest the important
roles of daily changing constituents in breast milk, especially in colostrum milk, in the nutrition of the newborn. Several
element peaks on a gelfiltration column were identified by comparison with standard samples. 相似文献