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151.
Okamura T Suzuki S Ogawa T Kobayashi J Kusuoka O Hatayama K Mochizuki M Hoshiya T Okazaki S Tamura K 《Journal of toxicologic pathology》2011,24(4):195-205
Recently, RccHan(TM):WIST (Wistar Hannover) rats were introduced to toxicity studies in Japan. The present study was performed to obtain control data for general toxicological parameters as an aid for interpretation of results in toxicity studies using this strain of rats. Four test groups comprising of 25 male and 25 female RccHan(TM):WIST rats were housed for 2, 4, 13 or 26 weeks from 6 weeks of age and observed and examined for clinical observation, body weight, food consumption, urinalysis, hematology, blood chemistry, organ weight, necropsy and/or histopathology. Ophthalmological examination was not conducted in this study, and the data in this report were obtained from an ongoing 104-week background study in RccHan(TM):WIST rats. These data were compared with the historical control data of CD(SD) (Sprague-Dawley) and/or F344 (Fischer) rats. The body weights of RccHan(TM):WIST rats were lower than those of CD(SD) rats and higher than those of F344 rats. The ophthalmological examination revealed a greater incidence of focal corneal opacity. Histopathology revealed focal mineralization of the cornea and Berlin blue-positive pigmentation in the epididymal interstitium as well as hepatocytes. Other than the above, some minor differences were found in urinalysis, hematology, blood chemistry and organ weights as compared with CD(SD) rats. 相似文献
152.
Onozato T Tamura T Nagasawa T Hayashi M Okuhara Y Kuroda J 《Journal of toxicologic pathology》2011,24(4):239-244
A subcutaneous mass was noted in the abdomen of a 50-week-old male Wistar Hannover GALAS rat. Histologically, the tumor was composed of vimentin-positive small round cells with scant cytoplasm arranged in a trabecular, sheet or pericytoma-like pattern and spindle cells arranged in a bundle pattern and vimentin-negative round cells proliferating in an island-shaped pattern. Argentophilic thin fibers were observed to wrap up the individual cells, and some of the tumor cells showed coexpression of vimentin and cytokeratin that formed juxtanuclear globes in the cytoplasm by double immunohistostaining. Transmission electron microscopy did not reveal any characteristic features suggesting cellular differention toward a specific cell type. Based on these findings, it was difficult to specify the origin, and the tumor was diagnosed as a poorly differentiated mesenchymal tumor and classified as a sarcoma, NOS (not otherwise specified). 相似文献
153.
Shin-ichi Miyata Hiroshi Kato Richard Davis Malcolm W. Smith Matthew Weinert Toru Iwanami 《Journal of General Plant Pathology》2011,77(1):43-47
‘Candidatus Liberibacter asiaticus’ is the most widespread of the three species of ‘Ca. Liberibacter’ that cause citrus greening disease (huanglongbing). To ascertain the phylogenetic relationships among Indian
isolates that have higher diversity in the 16S rDNA than Asian isolates of this species, we collected symptomatic leaves from
Northeast India, Papua New Guinea and Timor-Leste (East Timor) and detected ‘Ca. L. asiaticus’ by PCR using primers specific for nusG–rplK genes and 16S rDNA. Phylogenetic analysis with 16S rDNA sequences and single nucleotide polymorphisms of the omp gene region revealed that the Northeast Indian isolates were genetically closer to Asian-common isolates from Japan, Taiwan,
and Vietnam than to Indian isolates reported previously. Thus, the Asian-common strains of ‘Ca. L. asiaticus’ are apparently also present in Northeast India. 相似文献
154.
Noriko Furuya Nguyen Thi Ngoc Truc Toru Iwanami 《Journal of General Plant Pathology》2011,77(5):295-298
We determined and compared nucleotide sequences in the upstream region of the bacteriophage-type DNA polymerase in 15 Asian
isolates of the citrus-greening bacterium ‘Candidatus Liberibacter asiaticus’ using the genomic information of American isolate Psy62. Some isolates had nucleotide changes and
a large 156-bp deletion, which were concentrated in the putative bacteriophage genes ORF3 and ORF4 and corresponding intergenic
region. Eight partial recombination-like patterns were observed in this variable region. Most were confirmed to have occurred
between the original types 1 and 2, but a fragment, only several dozen nucleotides long and possibly derived from a third
type, was also identified. 相似文献
155.
Mako Yamamoto Tsuguyuki Saito Akira Isogai Manabu Kurita Teiji Kondo Toru Taniguchi Rumi Kaida Keiichi Baba Takahisa Hayashi 《Journal of Wood Science》2011,57(1):71-75
Holocellulose samples prepared from transgenic poplars overexpressing xyloglucanase had crystal widths of 3.2–3.5 nm as a
result of the (2 0 0) plane, based on their X-ray diffraction patterns, and crystal widths were greater than those of the
wild type (3.0 nm). Cellulose microfibril widths in the holocellulose samples were further determined from transmission electron
microscopic (TEM) images of individualized fibrils prepared by 2,2,6,6-tetramethylpiperidine-1-oxy radical-mediated oxidation
of the holocelluloses and the successive disintegration of the oxidized products in water. The TEM images also supported the
finding that cellulose microfibril widths of transgenic poplars were larger than those of the wild type. The cellulose microfibril
widths of transgenic poplars were approximately 6 nm, whereas those of the wild type were about 5 nm. However, such enlargement
of cellulose microfibril widths could not be explained by the increased cellulose contents of the transgenic poplars alone. 相似文献
156.
两种稻飞虱对杀虫剂的敏感性比较 总被引:8,自引:0,他引:8
分别于 2 0 0 0年和 2 0 0 1年测定了桂林、安庆和东台 3地区褐飞虱、白背飞虱对 10种杀虫剂的敏感性 ,并分析了两种飞虱对杀虫剂的敏感性差异。结果表明 ,在年度间和地区间 ,其敏感性差异不显著 ,而药剂间的差异显著。吡虫啉和醚菊酯是毒力最高的两个药剂 ,但吡虫啉的个体一致性较差 ,明显低于醚菊酯。合理利用这两个药剂 ,可以作为避免单一药剂长期使用、延缓抗性发展和延长药剂使用寿命的良策。 相似文献
157.
Reduced crop productivity due to soils containing toxic levels of boron (B) is a worldwide problem in food production. It is estimated that up to 17% of the barley yield losses in southern Australia are caused by B toxicity. We found that the expression of AtBOR4, an Arabidopsis paralog of BOR1, the first identified boron transporter gene, generates plants that are tolerant of high B levels. BOR4 is a polarly localized borate exporter that enhances B efflux from roots. The present study is a foundation for the improvement of crop productivity in soils containing excess B, which are distributed in arid areas of the world. 相似文献
158.
Kensuke Tanaka Shu Fujimaki Toru Fujiwara Tadakatsu Yoneyama 《Soil Science and Plant Nutrition》2013,59(2):311-313
To obtain direct evidence for the translocation of cadmium (Cd) via the phloem, we measured the Cd concentrations in the phloem sap of 5-week-old rice plants (Oryza sativa L. cv. Kantou) treated with a nutrient solution containing Cd. The phloem sap was collected from the leaf sheaths through the cut ends of stylets of the brown planthopper (Nilaparvata lugens Stål.). Cd concentrations in the phloem sap from the plants treated with 10 and 100 µM Cd for 3 d were 4.6 ± 3.4 and 17.7 ± 9.8 µM, respectively. Detection of Cd in the phloem sap indicated that Cd was translocated via sieve tubes in rice plants. Cd concentrations in the xylem exudate collected from the cut basis of the leaf sheaths of the plants treated with 10 and 100 µM Cd for 3 d were 18.9 ± 6.4 and 64.2 ± 14.6 µM, respectively. Cd concentrations in the phloem sap were significantly lower than those in the xylem exudate, indicating that Cd is not concentrated during the transfer from xylem to phloem. To our knowledge, this is the first determination of Cd concentrations in the phloem sap of plants, and the first direct proof that Cd is translocated via sieve tubes in rice plants. 相似文献
159.
Noriaki Aoki Kyotaro Noguchi Hiroaki Hayashi Toru Fujiwara 《Soil Science and Plant Nutrition》2013,59(7):1183-1185
We isolated a novel Arabidopsis thaliana mutant line that requires high levels of boron (B) for normal growth. Line 8–21 was identified from ethyl methanesulfonate-mutagenized M2 population. When grown in medium containing 3 μm or less B in the form of boric acid, the fresh weights of aerial portions of the mutant were about a half of those of the wild type, but in that containing 300 μm B, the growth appeared normal. The mutant plants did not shown any difference in root growth from the wild-type plants in the range of B concentrations tested. When grown with 30 μm B, the B concentration in shoots of the line 8–21 was similar to that in the wild-type, suggesting that the mutant could not utilize B efficiently. Line 8–21 was not allelic to bor1-1 (Noguchi et al., Plant Physiol., 115, 901–906, 1997). A significant portion of F2 plants from the crosses between the wild-type and the mutant grew poorly on a low B media, suggesting segregation of the mutation. 相似文献
160.
High boron (B) tolerance is an important trait for crop production in high-B soils. We previously reported that overexpression of BOR4, an Arabidopsis thaliana B exporter, conferred high B tolerance in A. thaliana. This improvement appeared to be mainly due to the decreased B concentrations in roots through BOR4-mediated exclusion of B. In the present study, we describe a novel role of overexpressed BOR4 in shoots for high B tolerance. We compared shoot growth of wild type A. thaliana and transgenic plants moderately overexpressing BOR4 in relation to B concentration in shoots. It was found that growths and chlorophyll accumulation of shoots containing similar levels of B are better in the transgenic plants than the wild type. This finding established that BOR4-overexpressing plants are more capable of expanding leaves and accumulating chlorophyll in the presence of high B in shoot tissues. BOR4-GFP was found to be localized to plasma membrane in leaf epidermis cells. We suggest that overexpressed BOR4 alters B distribution in leaves by exporting B from the cytoplasm to the apoplast, leading to enhancement of high B tolerance in shoots. 相似文献