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Shiori Fujiwara Yuko Yamaguchi Tsubasa Saito Tomomi Nakazawa Kazutoshi Tamura 《Journal of toxicologic pathology》2022,35(1):99
This case report describes a case of spontaneous pancreatic islet cell carcinoma with vascular invasion in a 110-week-old male F344 rat. Histologically, a pancreatic nodule consisting of tumor cells and many blood-rich vessels, and covered with a fibrous capsule showed local invasion in the capsule and adjacent acinar tissues, encircling a large duct-like structure (DS). The tumor was composed of well-differentiated tumor cells resembling normal pancreatic islet cells, which had small round nuclei and eosinophilic cytoplasm. Mitotic figures were rare. Immunohistochemistry revealed that the tumor cells were positive for insulin. Although endothelial cells were not detected, the DS wall showed cells positive for α-smooth muscle actin and elastic fibers, suggesting that the DS is the pancreatic artery. This is a rare case of islet cell carcinoma consisting of well-differentiated tumor cells with invasion of the pancreatic artery in a rat. 相似文献
3.
Cadmium transport and tolerance in rice: perspectives for reducing grain cadmium accumulation 总被引:10,自引:0,他引:10
In recent decades, numerous studies have attempted to project the impact of hypothesised anthropogenic climate change on rice production. In this study, we offer a comprehensive review of our current understanding related to temperature, CO2, and water-demand parameters in rice growth models. As to future rice yield, night time temperature should be focused in the models as well as day time temperature owing to the contribution of temperature on the night time respiration. Furthermore, although CO2-enhanced photosynthesis is critical for the accurate prediction of rice production in a higher CO2 atmosphere, we found that recent well-developed photosynthesis-stomatal model cannot realize the variation of CO2 stomatal sensitivity with humidity conditions. To estimate water stress under projected climate-change conditions, rice growth model should be required to link with water resource model, which includes natural processes and anthropogenic regulations. The understanding of abilities and limitations in the models is important not only to improve the schemes that models employ, but to also critically review the simulated results. 相似文献
4.
In 12th century, the Buddhist priest Eisai brought tea ( Camellia sinensis L.) seeds to Japan from China and now tea plants are cultivated all over Japan except in the Hokkaido and Tohoku districts. The quality (reflected in the price) of Japanese green tea is affected by the nitrogen content. Consequently in tea fields, for last three decades large amounts of fertilizer have been applied to produce high quality tea. As a result, problems such as acidification of soil have been caused. It is also known that the growth of tea plants is stimulated by the addition of aluminum (Al) under acidic conditions. In this keynote address, some problems caused by excess applications of fertilizer in tea fields and the growth characteristics of tea plants related to Al are presented. 相似文献
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Yoshikazu Kiriiwa Sunao Osumi Masanobu Endo Akira Nukaya Akio Morita Hiromi Yokota 《Soil Science and Plant Nutrition》2013,59(7):1119-1124
Abstract In alkaline soils, plant growth is impaired mainly by high pH and high concentration of bicarbonates. The bicarbonate concentration increases the pH value, and causes deficiency of iron. A bicarbonate-resistant cell line (BR line) of tobacco (Nicotiana tabacum L. cv. Burley21) was selected by adding excess bicarbonate ions (20 mmol L?1) to the culture medium. The pH of the medium was buffered 8.0 to 8.3. Under these conditions, about 80% of iron in the medium became insoluble. However, under such conditions, the BR line grew well. In this report, we examined some characteristics of the growth and iron uptake in the BR line under iron-deficient (i.e. high pH or no-iron) condition. At pH 5.8, the Fe3+ reduction activity was not significantly different between the non-selected line and the BR line. At pH 8.0, however, the Fe3+ reduction activity of the BR line was higher than that of the non-selected line. In no-iron condition, the growth of the non-selected line was markedly reduced after 2 weeks, while the BR line was not affected. The content of malic acid in both lines increased with the medium pH, and the content in the BR line was higher than that in the non-selected line. The BR line was able to adapt to the conditions, which restricted iron uptake, such as high bicarbonate concentration, high pH, and low iron conditions. The high ability of Fe3+ reduction was maintained at even high pH conditions. Further, the BR line may be able to improve the utilization of iron in the cells. 相似文献
7.
Masayasu Saruta Akio Kikuchi Akinori Okabe Takahide Sasaya 《Journal of General Plant Pathology》2005,71(6):431-435
Coat protein sequences of two isolates in strain A2 and five isolates in strain D of Soybean mosaic virus (SMV), which caused a recent mosaic outbreak in soybeans (cv. Sachiyutaka) in Chugoku and Shikoku in Japan, were compared
to published data on 15 other Asian-origin isolates. Sequence comparison and cluster analysis showed that SMV isolates of
strain A2 from these districts were closely related, as were those of strain D, but strains A2 and D were not. Thus, the two strains may have different origins and be carried through seed transmission. 相似文献
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9.
Pathological observations of feline mast cell tumor 总被引:1,自引:0,他引:1
10.
Sawada Y Yanai T Nakagawa H Tsukamoto Y Tamagawa Y Yokoi S Yanagi M Toya T Sugizaki H Kato Y Shirakura H Watanabe T Yajima Y Kodama S Masui A 《Pest management science》2003,59(1):49-57
Nineteen analogues were synthesized by modifying the tert-butylhydrazine moieties of N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-2,3-dihydro-1,4-benzodioxine-6-carbohydrazide and N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methylchromane-6-carbohydrazide (chromafenozide), and the synthesized analogues were evaluated for their insecticidal activity against Spodoptera litura F. While all of the synthesized analogues had insecticidal activity inferior to those of the lead compounds, several of the analogues nonetheless showed high insecticidal activity. Chromafenozide has shown very high selectivity toward lepidopteran species. 相似文献