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261.
262.
Katsumi Takaba Teruyoshi Imada Shigehisa Katsumata Hiroshi Okumura Sachiko Iwamoto Yui Suzuki Minami Imaizumi Kensuke Myojo Chie Takada Naoya Kimoto Koji Saeki Itaru Yamaguchi 《Journal of toxicologic pathology》2012,25(4):265-271
This study histopathologically and immunohistochemically investigated a spontaneously
occurring single mass subcutaneously located in the left lower abdomen of a female
BALB/cAJcl−nu/+ mouse at 10 weeks of age. The mass was about 20 × 15 × 10 mm
in size after formalin fixation; nevertheless, it was not detected by clinical observations at
9 weeks of age. H&E staining revealed the tumor origin was epithelial and probably arose
from the mammary gland, and the tumor cells demonstrated a squamous, acinar or polyhedral/basal
pattern. A cell kinetics analysis revealed that many of the tumor cells of the squamous, acinar
or polyhedral/basal component were positive for PCNA and cyclin D1, although there were a few
of TUNEL-positive tumor cells in all of the components. An epithelial/mesenchymal analysis
demonstrated that most of the tumor cells of the squamous and acinar components contained
keratin and E-cadherin; however, most of the tumor cells of the polyhedral/basal component were
less or very weakly positive for these markers. The tumor cells of the squamous component were
negative for vimentin and SMA; however, many of the tumor cells of the polyhedral/basal
component exhibited vimentin. In addition, expression of SMA was confirmed in some tumor cells
of the acinar and basal components. Based on the microscopic and immunohistochemical
characterizations, the tumor was diagnosed to be adenosquamous carcinoma that originated from
the mammary gland with rapid growth, and the tumor cells demonstrated epithelial-mesenchymal
transition-like changes. 相似文献
263.
Katsuhisa Shiraki Mihoko Ono Satoru Kajikawa Ayano Takeuchi Yuichi Murakami Yuji Oishi Masahiro Matsumoto 《Journal of toxicologic pathology》2012,25(4):273-276
The present report describes a rare case of spontaneous hemangiosarcoma in a nine-week-old
male Sprague-Dawley rat. At necropsy, multiple white nodules of various sizes were observed on
and within the enlarged spleen and liver and were histopathologically determined to be composed
of spindle- to oval-shaped cells that showed invasive growth without encapsulation and were
arranged solidly but partially in whorls or faint alveolar patterns with vascular-like spaces
containing small clefts or erythrocytes in the tumor mass. Immunohistochemical analysis
revealed that most of the tumor cells were strongly positive for vimentin, von Willebrand
factor (vWF) and CD34 but negative for podoplanin. In addition, electron microscopic
examination revealed the presence of Weibel-Palade bodies in the cytoplasm of the tumor cells.
Based on these findings, this case was diagnosed as a hemangiosarcoma. The splenic masses were
larger than the hepatic ones, with tumor cells mainly observed at periportal regions with tumor
embolism in the liver, suggesting that primary hemangiosarcoma initially developed in the
spleen before metastasizing. 相似文献
264.
Murata S Hayashi Y Kato A Isezaki M Takasaki S Onuma M Osa Y Asakawa M Konnai S Ohashi K 《Veterinary journal (London, England : 1997)》2012,192(3):538-540
Marek's disease virus serotype 1 (MDV-1) strains cause malignant lymphoma in chickens. MDV-1 has been previously reported to be widespread in white-fronted geese (Anser albifrons); however, the prevalence of MDV-1 in other wild birds has not been determined. In this study, we investigated the prevalence of MDV-1 in various wild birds in Hokkaido, Japan. The MDV-1 genome was widespread in geese and ducks, but was not detected in other birds. MDV-1 was detected in both sedentary and migratory species. These results suggest that, in Japan, MDV-1 is widespread in wild goose and duck populations, and that resident ducks may be significant carriers and reservoirs of MDV-1. 相似文献
265.
Masaki Hayashi Yuichi Saeki Michiyo Haga Kyuya Harada Hiroshi Kouchi Yosuke Umehara 《Breeding Science》2012,61(5):544-553
It has long been known that formation of symbiotic root nodules in soybean (Glycine max (L.) Merr.) is controlled by several host genes referred to as Rj (rj) genes, but molecular cloning of these genes has been hampered by soybean’s complicated genome structure and large genome size. Progress in molecular identification of legume genes involved in root nodule symbiosis have been mostly achieved by using two model legumes, Lotus japonicus and Medicago truncatula, that have relatively simple and small genomes and are capable of molecular transfection. However, recent development of resources for soybean molecular genetic research, such as genome sequencing, large EST databases, and high-density linkage maps, have enabled us to isolate several Rj genes. This progress has been achieved in connection with systematic utilization of the information obtained from molecular genetics of the model legumes. In this review, we summarize the current status of knowledge of host-controlled nodulation in soybean based on information from recent studies on Rj genes, and discuss the future research prospects. 相似文献
266.
A moderately persistent herbicide, simazine, has been used globally and detected as a contaminant in soil and water. The authors have isolated a simazine-degrading bacterium from a simazine-degrading bacterial consortium that was enriched using charcoal as a microhabitat. The isolate, strain CDB21, was gram-negative, rod-shaped (0.5-0.6 microm x 1.0-1.2 microm) and motile by means of a single polar flagellum. Based on 16S rRNA sequence analysis, strain CDB21 was identified as a novel beta-proteobacterium exhibiting 100% sequence identity with the uncultured bacterium HOClCi25 (GenBank accession number AY328574). PCR using primers that were specific for the genes of the atrazine-degrading enzymes (atzABCDEF) of Pseudomonas sp. strain ADP showed that strain CDB21 also possessed the entire set of genes of these enzymes. Nucleotide sequences of the atzCDEF genes of strain CDB21 were 100% identical to those of Pseudomonas sp. strain ADP. Sequence identity of the atzA genes between these bacteria was 99.7%. The 398-nucleotide upstream fragment of the atzB gene of strain CDB21 was 100% identical to ORF30 of Pseudomonas sp. strain ADP, and the 1526-nucleotide downstream fragment showed 99.8% sequence similarity to the atzB gene of the pseudomonad. 相似文献
267.
多花黑麦草抗病基因类似物的克隆及CAPS标记 总被引:1,自引:1,他引:0
多花黑麦草具有适应性强、生物产量高和品质好等优点,为我国南方及其他温带地区重要的牧草。本研究利用目前已克隆出的抗病基因(R基因)所编码的蛋白质结构上所具有的共同氨基酸基序NBS-LRR设计寡核苷酸简并引物,对多花黑麦草基因组进行抗病基因类似物(RGA)克隆。从克隆中筛选出具代表性的RGA克隆115个,设计RGA-STS引物113对。利用细胞质雄性不育(CMS)F1群体对RGA-STS引物进行筛选,并采用限制性内切酶酶切扩增多态序列(CAPS)法进行抗病类似物的分子标记,共检测到22对RGA-STS引物的扩增产物具多态性,22个RGA-CAPS标记均被标记于多花黑麦草遗传连锁图中。结果还表明RGA在多花黑麦草遗传连锁图中分布范围较广,并具有簇状分布特性。 相似文献
268.
Kaori Matsuoka Naoki Moritsuka Mitsuhiko Nukada Yuichi Saito Yuji Ono Shinnosuke Kusaba 《Journal of plant nutrition》2013,36(16):1952-1966
AbstractThe objective of this study was to investigate the effects of long-term application of ammoniacal N fertilizer for 43?years on the availability of 10 essential elements (B, N, Mg, K, Ca, Mn, Fe, Ni, Cu, and Zn) and Al in root-zone soils and their supply to ‘Jonathan’ apple trees. To achieve this objective, we used simultaneous multi-element analysis. To estimate the soil depth from which the apple trees took up these elements, we calculated the ratios of their concentrations in the N fertilized plot (N plot) to those in the no N plot (0?N plot) (N/0N ratio). Long-term N fertilization significantly increased the fruit and leaf N/0N ratios of N and Mn and significantly decreased that of K. These ratios in the fruits and leaves were similar to those in the 20–90?cm soil layer. This result suggests that N, K, and Mn in the fruits and leaves were supplied from the 20–90?cm soil layer. The N/0N ratios of all 11 elements in the fruits and leaves were significantly positively correlated with those in the 20–90?cm soil layer, but not in the 0–20?cm soil layer. Our findings indicate that long-term N fertilization altered the tree nutrition of not only N, but also K and Mn. These changes in the tree nutrition were ascribed to the fertilizer-induced changes in the availability of elements in the subsoils. 相似文献
269.
Nakamura A Watanabe K Ojima T Ahn DH Saeki H 《Journal of agricultural and food chemistry》2005,53(19):7559-7564
Scallop tropomyosin (TM), the major allergen of shellfish, was prepared from adductor muscles and reacted with four reducing sugars to investigate the effect of the Maillard reaction on the allergenicity of TM. The IgE-binding ability of TM increased significantly with the progress of the reaction with glucose, ribose, and maltose, but not with maltotriose. The allergenicity was enhanced at the early stage of the Maillard reaction, and the trend of the effect depended on the type of reducing sugar used. 2,4,6-Trinitrobenzenesulfonic acid treatment of the lysine residues in TM showed that the protein surface charge resulting from the Maillard reaction had no effect on the enhancement of the allergenicity. Thus, the change in the allergenicity would be closely related to the structural change caused by the Maillard reaction. 相似文献
270.
Effect of Long-term Fertilizer Application on the Concentration and Solubility of Major and Trace Elements in a Cultivated Andisol 总被引:1,自引:0,他引:1
Akira Takeda Hirofumi Tsukada Masami Nanzyo Yuichi Takaku Toyokazu Uemura Shun'ichi Hisamatsu Jiro Inaba 《Soil Science and Plant Nutrition》2005,51(2):251-260
The concentrations and solubility of major and trace elements in soils collected from a field for long-term experiments maintained for more than 60 years and the neighboring area were investigated in order to reveal the influence of soil management on their behavior in soils. No obvious differences in the element concentrations in soils were observed except for P and U, whose concentrations were elevated in the surface soils of the experimented field because of the long-term application of phosphate fertilizers. Soil acidification associated with the successive applications of potentially acid fertilizers had changed the solubility of many elements as follows: the solubility of Li, Be, Al, Mn, Co, Zn, Y, Cd, Ba and rare earth elements increased, while the solubility of P, As, Se, Nb, Sb, Mo and V increased by liming. In the uncultivated soils, the concentrations of Fe, Zr, Nb, Hf and Th in the water extracts were relatively high, and a certain amount of these elements in the water extracts may occur in colloidal forms. 相似文献