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681.
The gene (com1) encoding a 27-kDa outer membrane protein in 21 strains of Coxiella burnetii from a variety of clinical and geographical sources was sequenced for strain differentiation. The com1 gene was highly conserved among all the strains tested but there were several differences in nucleotide and deduced amino acid sequences. Based on the com1 gene-specific nucleotides and deduced amino acids, the 21 strains were divided into four groups. Group 1 contained 14 strains originating from ticks, cattle and human cases of acute Q fever. Groups 2 and 3 included 2 and 3 strains, respectively, originating from human cases of chronic Q fever. Group 4 contained 2 strains originating from a human case of acute Q fever and a goat with abortion. The results indicated that the strains originating from ticks, cattle and human cases of acute Q fever differed at the molecular level from those of human chronic Q fever. This study suggests that a sequence analysis of the com1 gene can be used for strain differentiation of C. burnetii.  相似文献   
682.
Anacystis nidulans R-2 cells were irradiated with near-UV light(295–390 nm) at an intensity that resulted in 30–40%survival. The near-UV light induced the preferential synthesisof sixteen proteins, which were designated UV-shock proteins.Several UV-shock proteins were also induced by heat shock (42?C)and six were synthesized by treatment with methyl viologen.The water-soluble fraction prepared from the cells generatedsuperoxide anion radicals upon irradiation with near-UV light,suggesting the production of active species of oxygen in cellsas a result of exposure to near-UV light. (Received February 18, 1991; Accepted May 24, 1991)  相似文献   
683.
A new aging method, fluorescent observation of burnt otoliths, was discovered to disclose the age and growth of the conger eel. Under UV light, bright fluorescent zones were visible in the burnt otolith but not in the unburnt otolith. An illumination wavelength around 380 nm was found to be suitable for fluorescence observation of burnt otoliths. Bright zones of the conger eel otolith formed around June–August in Sendai Bay and were validated as annuli. The conger eels caught by net pot fishery were found to be mainly aged from 1+ to 4+ years. Received: March 7, 2001 / Revised: September 12, 2001 / Accepted: October 10, 2001  相似文献   
684.
685.
Renal tubular dysplasia is a hereditary disease of Japanese black cattle showing renal failure and growth retardation with an autosomal recessive trait. In the present study, we mapped the locus responsible for the disease (RTD) by linkage analysis with an inbred paternal half-sib pedigree obtained from commercial herds. By analyzing segregation of microsatellite markers in the half-sibs, significant linkage was observed between the RTD locus and markers on bovine Chromosome (Chr) 1 with the highest lod score of 11.4. Homozygosity mapping with the inbred pedigree further defined the localization of the RTD locus in a 4-cM region between microsatellite markers BMS4003 and INRA119. Mapping of the RTD locus on bovine Chr 1 will facilitate cloning and characterization of the gene responsible for this disease. Received: 24 September 1999 / Accepted: 14 December 1999  相似文献   
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