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251.
Mika?OhtsukaEmail author Yoshino?Suzuki Tetsuya?Sakai Anil?N.?Netravali 《Fibers and Polymers》2004,5(3):225-229
The effect of UV and60Co gamma radiations on the physical and mechanical properties of nylon 6 mono-filaments with different draw ratios has been
studied. Specimens were exposed to either up to 25 Mrad of gamma or up to 168 hrs of intense UV irradiation. The results show
that nylon mono-filaments exposed to gamma rays, with much higher quantum energy than UV, undergo a larger extent of molecular
chain scission. Higher irradiation dose also results in the production of insoluble, macroscopic three-dimensional cross-linked
network structure. The amorphous regions with a lower density of cohesive energy (lower molecular orientation) show a higher
extent of cross linking reaction whereas amorphous regions with a higher density of cohesive energy (higher orientation) show
higher extent of chain scission reaction, irrespective of UV ray or gamma ray irradiation. 相似文献
252.
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
253.
Suzuki J Sasaoka F Fujihara M Watanabe Y Tasaki T Oda S Kobayashi S Sato R Nagai K Harasawa R 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(8):1113-1115
We examined the presence of hemoplasmas, hemotropic mycoplasmas, among 11 sheep (Ovis aries) with regenerative and hemolytic anemia and found six of them were positive by real-time PCR. The positive samples were then subjected to conventional PCR for direct sequencing of the 16S rRNA gene. Nucleotide sequences of all the positive samples were identified as the 16S rRNA gene of `Candidatus Mycoplasma haemovis' by phylogenetic analysis, demonstrating the infections with this particular hemoplasma species in Japan. 相似文献
254.
Okada Y Okutani A Suzuki H Asakura H Monden S Nakama A Maruyama T Igimi S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(12):1681-1684
The antimicrobial susceptibility of 201 Listeria monocytogenes isolates from foods, environments, animals and human patients in Japan was determined. All isolates were susceptible to ampicillin, the first choice of drug for listeriosis treatment, chloramphenicol, dihydrostreptomycin, erythromycin, enrofloxacin, gentamicin, kanamycin, lincomycin, nosiheptide, salinomycin, vancomycin, and virginiamycin. A human strain was resistant to oxytetracycline. The Minimum Inhibitory Concentration (MIC) for 50% of the strains and the MIC for 90% of the strains were comparable in all the isolates. This is the first investigation to compare antibiotic resistances between isolates from foods and isolates from human patients in Japan. The result showed that most of the isolates were susceptible to antibiotics used in this study. 相似文献
255.
Nishida H Nakayama M Tanaka H Kitamura M Hatoya S Sugiura K Suzuki Y Ide C Inaba T 《American journal of veterinary research》2011,72(8):1118-1123
256.
Tumor cell invasion into the surrounding nervous tissue is one of the histologic hallmarks of anaplastic meningiomas. To identify other possible markers for aggression in canine meningiomas, the relationship between histologic features and the expression of molecules involved in cell adhesion, cell proliferation, and invasion was examined. Immunohistochemistry for epithelial cadherin (E-cadherin), neural cadherin (N-cadherin), β-catenin, doublecortin (DCX), and Ki-67 was performed for 55 cases of canine meningioma. DCX was preferentially expressed in tumor cells invading the brain parenchyma (12 of 14 cases), suggesting its involvement in the invasion process. Regardless of the histologic type, E-cadherin and N-cadherin expression was observed in 31 of 55 and 44 of 55 cases, respectively. There was a significant positive correlation between DCX and N-cadherin expression and a significant negative correlation between E-cadherin and N-cadherin expression, suggesting that decreased E-cadherin and increased N-cadherin expression induce DCX expression. Typical membranous β-catenin expression was observed in 10 of 55 cases, whereas nuclear translocation was observed in 33 cases. Nuclear β-catenin expression was frequently found in anaplastic meningiomas (12 of 14 cases). The Ki-67 labeling indices were significantly higher in anaplastic meningiomas than in other types. These findings indicate that the expression of N-cadherin and DCX and the nuclear translocation of β-catenin are closely associated with the presence of invasion and anaplasia in canine meningiomas. Notably, granular cell meningiomas were negative for almost all the molecules examined, suggesting that they have a different tumor biology than other meningiomas. 相似文献
257.
Umeki S Suzuki R Shimojima M Ema Y Yanase T Iwata H Okuda M Mizuno T 《Veterinary immunology and immunopathology》2011,142(1-2):119-125
Thirteen different monoclonal antibodies against canine P-selectin glycoprotein ligand-1 (cPSGL-1) were obtained by immunization of rats with cells of a canine lymphoma cell line (Ema). O-sialoglycoprotein endopeptidase treatment of Ema cells showed that all of these antibodies recognized O-glycosylated peptides of canine PSGL-1. Experiments using deletion or point mutants of cPSGL-1 indicated that these antibodies could be categorized into several groups based on their cPSGL-1 recognition characteristics. These anti-cPSGL-1 monoclonal antibodies will be useful for analysis of the canine P-selectin and PSGL-1 system. 相似文献
258.
Tomonori Kume Nobuaki TanakaKoichiro Kuraji Hikaru KomatsuNatsuko Yoshifuji Taku M. SaitohMasakazu Suzuki Tomo’omi Kumagai 《Agricultural and Forest Meteorology》2011,151(9):1183-1192
This study was undertaken to quantify interannual variations of total evaporation (ET) in a tropical rainforest in Sarawak, Malaysia. To this end, we conducted 10-year meteorological measurements and formulated a simplified big-leaf model that reproduces transpiration (Et), rainfall interception (Ei), and ET as the sum of these. The model was validated independently using eddy covariance fluxes, rainfall interception based on throughfall and stemflow measurements, and sap flow measurements conducted for more than 2 years. Using the model, Et, Ei, and ET were estimated for the period 2000-2009. Annual Et, Ei, and ET averaged over 10 years were estimated as 1114, 209, and 1323 mm, respectively, with small seasonal fluctuations. The derived estimates showed conservative year-to-year variations in annual Et, Ei, and ET (CV = 5-7%) in contrast to considerable year-to-year variations in annual rainfall (CV = 11%). Specific rainfall characteristics (e.g. intense short duration storms) at this site can explain the conservative year-to-year Ei variations. Small interannual variations in meteorological conditions and absence of severe drought during the study period can explain the small year-to-year Et variations. To characterize ET at our site, we also compared Ei and ET at our site with those of other tropical forests. Based on the derived ET characteristics, we discuss possible ET changes in response to changes in rainfall regime at this site. 相似文献
259.
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
260.
Fermín G Keith RC Suzuki JY Ferreira SA Gaskill DA Pitz KY Manshardt RM Gonsalves D Tripathi S 《Journal of agricultural and food chemistry》2011,59(18):10006-10012
The virus-resistant, transgenic commercial papaya Rainbow and SunUp (Carica papaya L.) have been consumed locally in Hawaii and elsewhere in the mainland United States and Canada since their release to planters in Hawaii in 1998. These papaya are derived from transgenic papaya line 55-1 and carry the coat protein (CP) gene of papaya ringspot virus (PRSV). The PRSV CP was evaluated for potential allergenicity, an important component in assessing the safety of food derived from transgenic plants. The transgene PRSV CP sequence of Rainbow papaya did not exhibit greater than 35% amino acid sequence homology to known allergens, nor did it have a stretch of eight amino acids found in known allergens which are known common bioinformatic methods used for assessing similarity to allergen proteins. PRSV CP was also tested for stability in simulated gastric fluid and simulated intestinal fluid and under various heat treatments. The results showed that PRSV CP was degraded under conditions for which allergenic proteins relative to nonallergens are purported to be stable. The potential human intake of transgene-derived PRSV CP was assessed by measuring CP levels in Rainbow and SunUp along with estimating the fruit consumption rates and was compared to potential intake estimates of PRSV CP from naturally infected nontransgenic papaya. Following accepted allergenicity assessment criteria, our results show that the transgene-derived PRSV CP does not pose a risk of food allergy. 相似文献