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51.
Suppressive effect of potassium silicate on powdery mildew of strawberry in hydroponics 总被引:1,自引:0,他引:1
Takeshi?KantoEmail author Akihiro?Miyoshi Takuya?Ogawa Kazumasa?Maekawa Masataka?Aino 《Journal of General Plant Pathology》2004,70(4):207-211
From 1996 to 1997, potassium silicate (SiO2) was tested at 0, 25, 50, and 100mgl–1 in hydroponics to control powdery mildew. Other elements were added in the usual amounts, and the strawberries were cultivated hydroponically in a greenhouse for 4 months (from October to January). The powdery mildew spread in the control plot, but little mildew developed in the plot with 25mgl–1 silicate, and none in plots with more than 50mgl–1 silicate. The suppressive effect lasted for about 4 months on fruits and even longer on leaves. On analysis of mineral content in the leaves, only the silicate content differed markedly between the control and treated plants. Nitrogen, phosphate, potassium, and calcium contents did not differ greatly. The maximum silicate content was about 24 times that of the control, and disease severity decreased significantly when the content was more than 1.5% in the leaves. The hardness of the strawberry leaves, measured by a creep meter, was increased by the silicate treatment. 相似文献
52.
Okada T Shirai K Yamamoto Y Arai T Ogawa K Hosono K Kato M 《Science (New York, N.Y.)》2006,312(5778):1338-1341
X-ray fluorescence spectrometry of asteroid 25143 Itokawa was performed by the x-ray spectrometer onboard Hayabusa during the first touchdown on 19 November 2005. We selected those data observed during relatively enhanced solar activity and determined average elemental mass ratios of Mg/Si = 0.78 +/- 0.09 and Al/Si = 0.07 +/- 0.03. Our preliminary results suggest that Itokawa has a composition consistent with that of ordinary chondrites, but primitive achondrites cannot be ruled out. Among ordinary chondrites, LL- or L-chondrites appear to be more likely than H-chondrites. No substantial regional difference was found on the asteroid surface, indicating its homogeneity in composition. 相似文献
53.
Suzuki K Kanameda M Inui K Ogawa T Nguyen VK Dang TT Pfeiffer DU 《Research in veterinary science》2006,81(2):177-184
The objective of the study was to investigate constraints to dairy cattle health and production in rural smallholder communities in northern Vietnam, one of the target areas of the Vietnam government's dairy development programme. A total of 99 dairy farms (11 per commune) were recruited from 9 of 32 communes in Ba Vi District, using random two-stage cluster sampling. After the initial questionnaire interviews were conducted, farms were visited at three monthly intervals over a period of 1 year. Information on several health and production parameters relating to the study cattle was collected. Using multiple indicator modelling, it was found that Fasciola infestation, farmers who had been involved in dairying for longer (not indicative of better management skills), larger herd size, and cattle being kept in a shed were linked to reduced reproductive performances. 相似文献
54.
Murakami S Ogawa A Kinoshita T Matsumoto A Ito N Nakane T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(4):387-391
Fourteen diseased pigs from four farms in which there had been an outbreak of salmonellosis were investigated. Granulomatous inflammation with depletion of lymphocytes was observed in the swollen lymph nodes in these pigs. Antigens to porcine circovirus type 2 (PCV2) were immunolabeled in the lesions along with detection of viral DNA as PCV2 by polymerase chain reaction (PCR). In addition, antigens to porcine reproductive respiratory syndrome virus (PRRSV) were immunodetected in the lungs and Salmonella Choleraesuis was isolated from the affected pigs. The nine salmonellosis affected pigs, five (55.6%) with salmonellosis and PMWS concurrently infected with PRRSV were much higher than those infected with salmonellosis and PMWS (22.2%) or with salmonellosis and PPPRV (22.2%). 相似文献
55.
Ogawa H Chahota R Hagino T Ohya K Yamaguchi T Fukushi H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(7):743-745
Although birds infected with avian polyomavirus (APV) subclinically could be a source of infection, no epidemiological studies of APV in psittacine birds have been reported in Japan. In the present study, we investigated subclinical morbidity rate of APV in imported and domestically bred psittacine birds by polymerase chain reaction (PCR). Of 402 live birds from which blood or feather samples were taken between April, 2003 and March, 2004, 11 (2.7%) were found to be APV positive. The DNA sequences of the APV t/T antigen region were determined for five APV-positive randomly selected samples and were found to be conserved. 相似文献
56.
PKA implicated in the phosphorylation of Cx43 induced by stimulation with FSH in rat granulosa cells 总被引:3,自引:0,他引:3
Yogo K Ogawa T Akiyama M Ishida-Kitagawa N Sasada H Sato E Takeya T 《The Journal of reproduction and development》2006,52(3):321-328
Connexin 43 (Cx43)-mediated gap junctional communication in granulosa cells is crucial for germ line development and postnatal folliculogenesis. We previously showed that follicle-stimulating hormone (FSH) promoted phosphorylation of Cx43 in rat primary granulosa cells. We further identified Ser365, Ser368, Ser369, and Ser373 in the carboxy-terminal tail as the major sites of phosphorylation by FSH, and found that the phosphorylation of these residues was essential for channel activity. In this study, we investigated the protein kinase(s) responsible for FSH-induced phosphorylation. H89, a cyclic AMP-dependent protein kinase (PKA) inhibitor, inhibited FSH-induced phosphorylation both in vivo and in vitro, whereas PD98059, a mitogen-activated protein kinase kinase (MEK) inhibitor, had little effect on the phosphorylation level. Ca2+-dependent protein kinase (PKC) appeared to negatively regulate phosphorylation. Phosphopeptide mapping with or without H89 treatment indicated that PKA could be responsible for phosphorylation of the four serine residues. In addition, the purified catalytic subunit of PKA could phosphorylate the recombinant C-terminal region of Cx43, but not the variant in which all four serine residues were substituted with alanine. These results suggest that FSH positively regulates Cx43-mediated channel formation and activity through phosphorylation of specific sites by PKA. 相似文献
57.
Ito D Ibanez C Ogawa H Franklin RJ Jeffery ND 《American journal of veterinary research》2006,67(6):1050-1056
OBJECTIVE: To evaluate the numbers and proportions of olfactory ensheathing cells (OECs) in cell cultures derived from the olfactory bulb (OB) and olfactory mucosa of dogs. ANIMALS: 7 dogs. PROCEDURES: OB tissue and olfactory mucosa from the nasal cavity and frontal sinus were obtained from euthanatized dogs and prepared for cell culture. At 7, 14, and 21 days of culture in vitro, numbers and proportions of OECs, astrocytes, and fibroblasts were determined via immunocytochemistry. Antibody against the low-affinity nerve growth factor receptor p75 was used to identify OECs, antibody against glial fibrillary acidic protein was used to identify astrocytes, and antibody against fibronectin was used to identify fibroblasts. RESULTS: Cultured OECs derived from the olfactory mucosa of the nasal cavity and frontal sinus had similar characteristics. However, whereas OECs in the OB cell cultures constituted approximately 50% of the cells at 7 days and approximately 75% at 21 days the proportion of OECs in cultures derived from both mucosal types was much lower, with approximately 40% OECs at 7 days and approximately 25% at 21 days. Analysis of OEC numbers revealed that these changes were accompanied by corresponding decreases and increases in the population of cells with fibronectin receptors. CONCLUSIONS AND CLINICAL RELEVANCE: Although olfactory mucosal cell cultures yielded a sufficient number of OECs for spinal cord transplantation procedures in dogs, modification of culture conditions would be required to ensure that the derived cell population contained a sufficient proportion of OECs. 相似文献
58.
Takeshi Toyoda Jun-ichi Akagi Young-Man Cho Yasuko Mizuta Saeko Onami Isamu Suzuki Kumiko Ogawa 《Journal of toxicologic pathology》2013,26(2):215-221
To evaluate the potential role of DNA repair in bladder carcinogenesis, we performed an immunohistochemical analysis of expression of various DNA repair enzymes and γ-H2AX, a high-sensitivity marker of DNA double-strand breaks, in the urothelium of male F344 rats treated with N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN), a bladder-specific carcinogen. Our results clearly demonstrated that γ-H2AX aggregation was specifically generated in nuclei of bladder epithelial cells of BBN-treated rats, which was not found in untreated controls or mesenchymal cells. γ-H2AX-positive cells were detected not only in hyperplastic and neoplastic areas but also in the normal-like urothelium after BBN treatment. These data indicate that γ-H2AX has potential as a useful biomarker for early detection of genotoxicity in the rat urinary bladder. To the best of our knowledge, this is the first report demonstrating expression of γ-H2AX during bladder carcinogenesis. 相似文献
59.
Masuda T Odaka Y Ogawa N Nakamoto K Kuninaga H 《Journal of agricultural and food chemistry》2008,56(2):597-601
Lemongrass is a popular Asian herb having a lemon-like flavor. Very recently, potent tyrosinase inhibitory activity has been found in lemongrass in addition to various biological activities reported in the literature. The aim of the present study is to identify the active compounds in the lemongrass. An assay-guided purification revealed that one of the active substances was geranic acid. Geranic acid has two stereoisomers, which are responsible for the trans and cis geometry on the conjugated double bond. Both isomers are present in the active ethyl acetate-soluble extract of the lemongrass, and their IC50 values were calculated to be 0.14 and 2.3 mM, respectively. The structure requirement of geranic acid for the potent tyrosinase inhibitory activity was investigated using geranic acid-related compounds. 相似文献
60.
Ogawa K Sakakibara H Iwata R Ishii T Sato T Goda T Shimoi K Kumazawa S 《Journal of agricultural and food chemistry》2008,56(12):4457-4462
The anthocyanin composition and antioxidant activity of the crowberry ( Empetrum nigrum) were studied. High-performance liquid chromatography (HPLC) combined with a diode array detector and electrospray ionization mass spectrometry were used for identification and quantification of individual anthocyanins. Freeze-dried crowberry powder was extracted with 80% methanol containing 0.5% acetic acid and subjected to HPLC. Thirteen kinds of anthocyanins were identified. The major anthocyanins were cyanidin-3-galactoside and delphinidin-3-galactoside, at 8.04 and 8.62 mg/g extract, respectively. The HPLC profile of crowberry extract was similar to bilberry and blueberry. The total content of anthocyanins in crowberry was 41.8 mg/g extract, higher than the other nine major berry species (2.5-38.8 mg/g extract). The antioxidant activity was also evaluated using the 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azinobis(3-ethybenzothiazoline-6-sulfonic acid) radical quenching assays and the ferric reducing activity power assy. Crowberry extract exerted the strongest antioxidant activity. In conclusion, individual anthocyanins in crowberry were identified and then quantified in this study. Additionally, crowberry is suggested to be associated with a reduction in the risk of developing chronic diseases because of its strong antioxidant activity. 相似文献