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81.
Mami Murakami Hiroki Sakai Nao Iwatani Aki Asakura Yuki Hoshino Takashi Mori Tokuma Yanai Kohji Maruo Toshiaki Masegi 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(1):113-118
Abstract: A 15‐month‐old castrated male dog with a history of intermittent epistaxis and sneezing was admitted for the examination of a maxillofacial mass. An impression smear of a biopsy sample from the cauliflower‐shaped gingival mass contained numerous round cells, 5–25 μm in diameter, which contained a moderate amount of clear to pale blue cytoplasm and resembled lymphoid cells. Mitotic figures were frequently observed. The mass was diagnosed as malignant round cell neoplasia. On histologic examination the tumor was composed of diffusely arranged, small, atypical round cells with a small amount of fibrovascular stroma. Immunohistochemically, the cells were negative for CD3, CD18, CD20, CD79α, cytokeratin, melan‐A, chromogranin A, α‐smooth muscle actin, and myoglobin but positive for vimentin and desmin. The cells also had strong positive nuclear staining for myogenin and MyoD1. A diagnosis of solid‐pattern alveolar rhabdomyosarcoma was made on the basis of morphologic and immunohistochemical results. Alveolar rhabdomyosarcoma should be considered in the differential diagnosis of tumors in juvenile dogs, especially when cytologic findings reveal round, undifferentiated cells. 相似文献
82.
Maximum prey size estimation of longtooth grouper,Epinephelus bruneus,using morphological features,and predation experiments on juvenile cannibalism 下载免费PDF全文
Nariaki Inoue Jun Satoh Tohru Mekata Takashi Iwasaki Koichiro Mori 《Aquaculture Research》2016,47(2):605-611
In fish culture, cannibalism, which induces critical damage, is separated into two types: type I, which occurs in early larval stages when size heterogeneity is low; and type II, which starts in later larval and/or early juvenile stages following type I when size heterogeneity is high. In type II, the cannibal's maximum prey size is limited by its gape size relative to the prey fish body size. Ratios of prey to cannibal body size changes are associated with allometric factors and feeding behaviour with growth. In a previous study on grouper, the maximal prey size was estimated morphologically (i.e., the relationship between gape size and body height). This method is very simple and useful; however, it does not consider allometric factors and feeding behaviour changes; therefore, it probably causes a large estimation error. To overcome this, we present a new method for estimating maximal prey size to determine the size ranges for size grading of longtooth grouper, Epinephelus bruneus, juveniles using predation experiments. It is shown that grouper type II cannibalism is affected by two factors; in early juvenile stages by morphology and in later (TL over 50 mm) by prey size selectivity. 相似文献
83.
Masahiko Mori Kento Maki Tsubasa Kawahata Daigo Kawahara Yuta Kato Toru Yoshida Hidetaka Nagasawa Hitoshi Sato Atsushi J. Nagano Paul C. Bethke Kiyoaki Kato 《Breeding Science》2021,71(2):208
Epicotyl length (ECL) of adzuki bean (Vigna angularis) affects the efficiency of mechanized weeding and harvest. The present study investigated the genetic factors controlling ECL. An F2 population derived from a cross between the breeding line ‘Tokei1121’ (T1121, long epicotyls) and the cultivar ‘Erimo167’ (common epicotyls) was phenotyped for ECL and genotyped using simple sequence repeats (SSRs) and single-nucleotide polymorphism (SNP) markers. A molecular linkage map was generated and fifty-two segregating markers, including 27 SSRs and 25 SNPs, were located on seven linkage groups (LGs) at a LOD threshold value of 3.0. Four quantitative trait loci (QTLs) for ECL, with LOD scores of 4.0, 3.4, 4.8 and 6.4, were identified on LGs 2, 4, 7 and 10, respectively; together, these four QTLs accounted for 49.3% of the phenotypic variance. The segregation patterns observed in F5 residual heterozygous lines at qECL10 revealed that a single recessive gene derived from T1121 contributed to the longer ECL phenotype. Using five insertion and deletion markers, this gene was fine mapped to a ~255 kb region near the end of LG10. These findings will facilitate marker-assisted selection for breeding in the adzuki bean and contribute to an understanding of the mechanisms associated with epicotyl elongation. 相似文献
84.
Effect of plastic-film mulching on leaching of nitrate nitrogen in an upland field converted from paddy 总被引:4,自引:0,他引:4
Tomokazu?HaraguchiEmail author Atsushi?Marui Kozue?Yuge Yoshisuke?Nakano Ken?Mori 《Paddy and Water Environment》2004,2(2):67-72
A lysimeter experiment was conducted to examine the effects of plastic film mulching on the leaching rate of nitrate nitrogen (NO3-N) from chemical fertilizer that was applied to an upland field that had been converted from paddy rice production. Leaching was monitored in two lysimeters filled with sandy loam soil, which contained low soil organic matter content, under different surface mulch conditions. One was mulched only on the ridge (ridge-mulch treatment) and another one was mulched fully, including the furrow, with black plastic film (full-mulch treatment). Chemical fertilizer was mixed into the top 0.2 m of soil in the two lysimeters before installing the mulch. After transplanting broccoli, the amount of subsurface discharge water and the NO3-N concentrations in the discharge water were measured every day. Larger NO3-N discharges occurred in the ridge-mulch treatment for three days after heavy rainfalls in which cumulative precipitation exceeded 10 mm, and the daily NO3-N load was twice as large as the full-mulch treatment. The differences in the amount of subsurface discharge water and NO3-N discharged between treatments were not significant when there was no rainfall. Cumulative NO3-N loads for the ridge- and full-mulch treatment during the last month of the experimental period were 0.246 and 0.195 g m–2, respectively. The effect of mulching on the reduction of NO3-N discharge rate was higher for the full-mulch treatment. This result showed that a plastic-film mulching system would be effective as an appropriate fertilizer management to reduce nitrate-leaching losses. 相似文献
85.
Seventy-three breeding lines and cultivars, which included all Japanese cultivars, were assessed by random amplified polymorphic DNA (RAPD) analysis. Thirty-one of 40 decamer primers revealed 84 scorable RAPDs. Using these RAPDs, 67 of 73 cultivars were distinguished from each other. One of the cultivars released as a protoclonal variant was able to distinguish from the parent by increasing the number of primers surveyed. Based on the number of different RAPDs between each pair of accessions, cluster analysis was performed to exploit genetic diversity in Japanese cultivars. Closely related cultivars deduced from their pedigrees were clustered closely, indicating that similarities based on the presence vs. absence of RAPDs were reflections of genetic similarities. Old Japanese cultivars, as suggested by their similarity of chloroplast DNA toS. tuberosum ssp.andigena, were indeed clustered with ssp.andigena accessions, supporting these were relic cultivars of early European potatoes. The present study suggests that Japanese potatoes are an interesting mass of genetic diversity including North American, European, and Andean germplasms and relic potatoes. 相似文献
86.
Morimoto M Takagi Y Higashi N Suzuki T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(10):1257-1263
Rutin is one of the flavonoids derived from plants such as buckwheat and is well known as a powerful antioxidant. To determine whether dietary rutin could modulate mucosal immunity, we examined the gene expression of Th1/Th2 cytokines and the receptors in the gut and lung. Aged (18 months old, 18 M) C3H/HeN female mice were orally administered rutin for 10 days. The small intestine and lung were taken and analyzed by real-time PCR for gene expression. Interleukin (IL)-13 and IL-13Rα2 gene expression was significantly low (P<0.05 respectively) in the small intestine of aged rutin-fed mice. Meanwhile, there was no change in interferon γ gene expression between control and rutin-fed mice. IL-13 gene expression was also downregulated in the lung. To examine the mechanism of the inhibitory effect of rutin on Th2 cytokines in aged mice, intestinal nitric oxide synthase (NOS) expression was evaluated. Rutin inhibited inducible NOS (NOS2) gene expression, but not neuronal NOS and endothelial NOS. Gene analysis of cells collected from the small intestine by laser capture dissection revealed that NOS2 expression was significantly inhibited in crypt regions. Thus, rutin might be effective against a Th2-dominant profile through NOS2 inhibition in aged mice. 相似文献
87.
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89.
Tsuboi M Etoh H Kato K Nakatugawa H Kato H Maejima Y Matsumoto G Mori H Hosokawa M Miyashita K Tokuda H Suzuki N Maoka T 《Journal of agricultural and food chemistry》2011,59(19):10572-10578
The in vitro reactivity of capsanthin (1) and fucoxanthin (2) with peroxynitrite was investigated, and the reaction products produced by scavenging with peroxynitrite were analyzed. (14'Z)-Nitrocapsanthin (3) and 12-nitrocapsanthin (4) were isolated from the products of the reaction of capsanthin with peroxynitrite. Similarly, (14Z)-15-nitrofucoxanthin (5), (11Z)-11-nitrofucoxanthin (6), and (14Z,9'Z)-15-nitrofucoxanthin (7) were obtained from the reaction of peroxynitrite reaction with fucoxanthin. Capsanthin and fucoxanthin inhibited the nitration of tyrosine by peroxynitrite. Furthermore, nitrocapsanthins (3 and 4) and nitrofucoxanthins (5 and 6) exhibited an inhibitory effect on Epstein-Barr virus early antigen activation in Raji cells and an antiproliferative effect on human pancreatic carcinoma. Moreover, nitrocapsanthins (3 and 4) inhibited carcinogensis of mouse skin tumors initiated by 7,12-dimethylbenz[a]anthracene (DMBN). 相似文献
90.