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111.
A biovar 3-specific primer set Ab3-F3/Ab3-R4 was designed based on the comparison of sequences of the 16S rDNA region of agrobacteria and related rhizobia for rapid identification of Agrobacterium biovar 3 strains. A 570-bp 16S rDNA fragment was amplified from cell lysates of Agrobacterium biovar 3 strains by polymerase chain reaction (PCR) using Ab3-F3/Ab3-R4 primers. Discrimination of Agrobacterium tumefaciens biovar 3 from Agrobacterium radiobacter biovar 3 and of Agrobacterium biovar 3 strains from other Agrobacterium strains was done simultaneously using multiplex PCR with a mixture of two primer sets (Ab3-F3/Ab3-R4 and VCF3/VCR3) previously designed for the virC region of Ti-plasmid and Ri-plasmid.  相似文献   
112.
With the colony polymerase chain reaction (PCR), the specificity of newly prepared primer sets VCF2/VCR2, VCF3/VCR3, VCF4/VCR4, and VCF5/VCR5 to Ti or Ri plasmids in Agrobacterium strains were compared to that of the conventional set VCF/VCR. At first, control strains, which consisted of a nonpathogenic strain and phytopathogenic strains carrying Ti or Ri plasmid, were used. VCF3/VCR3 and VCF5/VCR5 were highly specific to all the phytopathogenic strains, whereas the others were not. These two primer sets were superior to VCF/VCR in their specificity with colony PCR to tumorigenic Agrobacterium strains isolated from apple saplings.  相似文献   
113.
Characteristics such as flower form, size and color of outer and inner perianths, anthocyanins in outer perianths, size, color and fertility of pollen and self-fertility of diploid and tetraploid lines regenerated via protoplast culture of Iris fulva were examined and compared with those of the diploid wild line. Among these characteristics, flower form, inner and outer perianth sizes of the tetraploid lines were noticeable, because these lines had upward flower forms and bigger flowers than diploid lines. Furthermore, reciprocal crosses between diploid or tetraploid lines of I. fulva and I. ensata and those of I. fulva and I. laevigata were performed. Three seedlings were obtained from the cross of tetraploid I. fulva × diploid I. laevigata through embryo rescue. One of them was identified as the interspecific hybrid between tetraploid I. fulva and I. laevigata by flow cytometoric (FCM), cytological and molecular (RAPD) analyses. This is the first report on production of hybrids from these lines. I. fulva has unique brown flowers, and this trait could be very useful for flower color breeding of I. laevigata which lacks this color. Therefore, the hybrid of I. fulva (4×) × I. laevigata may be the best available gene source for brown color breeding of this species.  相似文献   
114.
115.
Alstroemeria plants were surveyed for viruses in Japan from 2002 to 2004. Seventy-two Alstroemeria plants were collected from Aichi, Nagano, and Hokkaido prefectures and 54.2% were infected with some species of virus. The predominant virus was Alstroemeria mosaic virus, followed by Tomato spotted wilt virus, Youcai mosaic virus (YoMV), Cucumber mosaic virus (CMV), Alstroemeria virus X and Broad bean wilt virus-2 (BBWV-2). On the basis of nucleotide sequence of the coat protein genes, all four CMV isolates belong to subgroup IA. CMV isolates induced mosaic and/or necrosis on Alstroemeria. YoMV and BBWV-2 were newly identified by traits such as host range, particle morphology, and nucleotide sequence as viruses infecting Alstroemeria. A BBWV-2 isolate also induced mosaic symptoms on Alstroemeria seedlings.  相似文献   
116.
The generalized static solution of the Triangular Running Skyline (TRS) system has been derived. A pair of tail spars with a haulback line enables the carriage of the TRS system to move around over the triangular area formed by connecting the bases of the three spars with each other,i.e., the two tail spars and one head spar. From the head spar, the main and slack-pulling lines stretch toward the carriage to move up and down the load. The theory derived in this paper separately evaluates the line lengths and line tensions of the main and slack-pulling lines (the four-line model), while the previous theory treats these two lines as a single equivalent line (the three-line model). Four numerical examples provided in this paper ascertained the accuracy of the two procedures of the four-line model. A part of this paper was orally presented at the Second Annual Meeting of the Japanese Forest Engineering Association, November 18, 1995, Tokyo. This English title is a tentative translation form the original Japanese by the authors of this paper.  相似文献   
117.
It is desirable to produce beef with high levels of monounsaturated fatty acids (MUFA), as this is related to fat softness and palatability. However, the physiology of MUFA synthesis in bovine fat during the fattening process remains to be established. In this study, in order to elucidate the relationship between plasma components and the fatty acid composition of intramuscular fat, we investigated the effect of plasma obtained from fattening cattle on the messenger RNA (mRNA) expressions of the adipogenesis‐related gene in a clonal bovine intramuscular preadipocyte line (BIP cells). The mRNA expressions of stearoyl‐CoA desaturase, adipocyte Protein 2, peroxisome proliferator‐activated receptor gamma and sterol regulatory element‐binding protein 1 in BIP cells were significantly higher following treatment with those plasma samples collected from the cattle with the highest diaphragmatic unsaturated fatty acids to saturated fatty acids ratio (US/S). Furthermore, the concentration of nonesterified fatty acid (NEFA) in the plasma samples had an inverse correlation with carcass diaphragmatic US/S. These results indicate that cattle with a low ratio of US/S in fat may be discriminated from the population of fattening cattle before slaughter by measuring the effect of their plasma on gene expression in BIP cells as well as their plasma concentration and composition of NEFA.  相似文献   
118.
It is well known that the immune system changes with age during development and maturation in Holstein cattle. But age-related changes in leukocytes and T cell subsets in peripheral blood of Japanese Black cattle still remain unclear. The aim of the present study was to investigate comparative changes of leukocytes (granulocytes, monocytes, B cells and T cells) and T cell subsets (CD4+, CD8+, γδ, CD8+γδ and WC1+γδ T cells) in Japanese Black cattle aged 0.5, 1, 2, 6, 18 and 36–41 (adult) months on flow cytometry using specific monoclonal antibodies for the cell surface markers. T cell proportion was approximately 40% in 2-month-old cattle and decreased to 20.6% in adults. In contrast, B cell proportion significantly increased from 7.4% to 28.2% with age. In T cell subsets the percentage of CD4+ T cells significantly increased from 40.5% to 60%, but that of WC1+γδ T cell subset significantly decreased with age. The percentages of CD8+ and CD8+γδ T cells did not change. The present study details the proportional changes in leukocyte and T cell subsets with age in the peripheral blood of Japanese Black cattle and these findings are similar to those described for Holstein cattle.  相似文献   
119.
Growing evidence suggests that insulin interacts with both orexigenic and anorexigenic peptides in the brain for the control of feeding behavior in mammals. However, the action of central insulin in chicks has not yet been identified. In the present study, we investigated the effects of central injection of insulin on feeding behavior in chicks. Intracerebroventricular (ICV) administration of insulin, at doses that do not influence peripheral glucose levels, significantly inhibited food intake in chicks. Central injection of insulin in chicks significantly increased expression of pro-opiomelanocortin (POMC) mRNA, and decreased that of neuropeptide Y (NPY) mRNA. Finally, co-injection of the melanocortin antagonist (SHU9119 or HS014) prevented the reduction in food intake caused by ICV administration of insulin. These data suggest that insulin functions in chicks as an appetite-suppressive peptide in the central nervous system, and that the central melanocortin system mediates this anorexic effect of insulin, as in mammals.  相似文献   
120.
The aim of the current study was to examine the effects of clenbuterol injection into newly hatched chicks on both the abdominal fat pad tissue weight and the skeletal muscle weight during subsequent growth. Twenty‐seven 1‐day‐old chicks were divided into two groups, receiving either a single intraperitoneal (i.p.) injection of clenbuterol (0.1 mg/kg body weight) or phosphate‐buffered saline (PBS). Body weight gain, feed intake and feed conversion ratio were not affected by clenbuterol injection during the 5‐week experimental period, while the abdominal fat pad tissue weight of the clenbuterol‐injected chicks was lower than that of the control chicks at 5 weeks post‐injection. Plasma non‐esterified fatty acid concentrations were significantly increased in the clenbuterol‐injected chicks, while plasma triacylglycerol concentrations did not differ. Additionally, the enzymatic activity of fatty acid synthase was lower in the liver of the clenbuterol‐injected chicks. Conversely, the skeletal muscle weights were not affected by clenbuterol injection. These results suggest that a single clenbuterol injection into 1‐day‐old chicks decreases the abdominal fat pad tissue weight, but may not affect skeletal muscle weights during growth. © 2015 Japanese Society of Animal Science  相似文献   
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