青梅果实的采后成熟特性和肉质变化   总被引：8，自引：0，他引：8  

薛彦斌  久保康隆 《中国南方果树》1999,28(3):34-37

研究了２０℃,相对湿度９３％条件下青梅果实的采后成熟特性和肉质变化,结果表明,青梅果实采后呼吸活性和乙烯生成量随着成熟作用的进展而加大,乙烯生成量极高,在呼吸类型上属于跃变型果实;果皮急速黄化,果肉急速软化,主要原因在于多聚半乳糖醛酸酶,果胶甲酯酶活性的增大,导致水溶性果胶含量上升和盐酸可溶性果胶含量的下降。  相似文献   

Long-term Pulmonary Responses to Quadweekly Intermittent Intratracheal Spray Instillations of Magnetite (Fe3O4) Nanoparticles for 52 Weeks in Fischer 344 Rats     

Yukie Tada  Norio Yano  Hiroshi Takahashi  Katsuhiro Yuzawa  Hiroshi Ando  Yoshikazu Kubo  Akemichi Nagasawa  Akiko Inomata  Akio Ogata  Dai Nakae 《Journal of toxicologic pathology》2013,26(4):393-403

Information about potential risks of iron nanomaterials is still limited, while a wide variety of applications are expected. We recently reported acute phase responses of male and female Fischer 344 rats after a single intratracheal spray instillation of Fe₃O₄ nanoparticles (magnetite), clearly showing dose-dependent pulmonary inflammatory changes (Tada et al., J Toxicol Pathol 25, 233–239, 2012). The present study assessed long-term responses of male and female Fischer 344 rats to multiple administrations of magnetite. Ten-week-old male and female Fischer 344 rats (n=20/group) were exposed to a total of 13 quadweekly intermittent intratracheal spray instillations of magnetite during the experimental period of 52 weeks, at doses of 0, 0.2 (low), 1.0 (medium) and 5.0 (high-dose) mg/kg body weight per administration. Absolute and relative lung weights of the high-dose group were significantly higher than those of the control group. Macroscopically, slight enlargement and scattered black patches were recognized in the lungs and the lung-associated lymph nodes of the high-dose group. Histopathologically, infiltration of macrophages phagocytosing magnetite (all dose groups) and of chronic inflammatory cells (medium- and high-dose males and high-dose females), alveolar bronchiolization and granuloma (high-dose group) were observed. In addition, alveolar hyperplasias were observed in some rats of the high-dose group, and cytoplasmic overexpression of β-catenin protein was immunohistochemically found in such lesions. The present results clearly show that instilled magnetite causes chronic inflammatory responses in the lung. These responses occur in a dose-dependent manner without apparent differences among sexes  相似文献   

Fish intake and the risk of fatal prostate cancer: findings from a cohort study in Japan     

Pham TM  Fujino Y  Kubo T  Ide R  Tokui N  Mizoue T  Ogimoto I  Matsuda S  Yoshimura T 《Public health nutrition》2009,12(5):609-613

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Plastic deformation of MgGeO3 post-perovskite at lower mantle pressures     

Merkel S  Kubo A  Miyagi L  Speziale S  Duffy TS  Mao HK  Wenk HR 《Science (New York, N.Y.)》2006,311(5761):644-646

Polycrystalline MgGeO3 post-perovskite was plastically deformed in the diamond anvil cell between 104 and 130 gigapascals confining pressure and ambient temperature. In contrast with phenomenological considerations suggesting (010) as a slip plane, lattice planes near (100) became aligned perpendicular to the compression direction, suggesting that slip on (100) or (110) dominated plastic deformation. With the assumption that silicate post-perovskite behaves similarly at lower mantle conditions, a numerical model of seismic anisotropy in the D' region implies a maximum contribution of post-perovskite to shear wave splitting of 3.7% with an oblique polarization.  相似文献   

Antibacterial activity of coriander volatile compounds against Salmonella choleraesuis     

Kubo I  Fujita K  Kubo A  Nihei K  Ogura T 《Journal of agricultural and food chemistry》2004,52(11):3329-3332

Aliphatic (2E)-alkenals and alkanals characterized from the fresh leaves of the coriander Coriandrum sativum L. (Umbelliferae) were found to possess bactericidal activity against Salmonella choleraesuis ssp. choleraesuis ATCC 35640. (2E)-Dodecenal (C(12)) was the most effective against this food-borne bacterium with the minimum bactericidal concentration (MBC) of 6.25 microg/mL (34 microM), followed by (2E)-undecenal (C(11)) with an MBC of 12.5 microg/mL (74 microM). The time-kill curve study showed that these alpha,beta-unsaturated aldehydes are bactericidal against S. choleraesuis at any growth stage and that their bactericidal action comes in part from the ability to act as nonionic surfactants.  相似文献   

Enzyme-linked immunosorbent assay based on a polyclonal antibody for the detection of the insecticide fenitrothion. Evaluation of antiserum and application to the analysis of water samples.     

Eiki Watanabe  Yukiko Kanzaki  Hiroshi Tokumoto  Ryoko Hoshino  Hiroaki Kubo  Hiroyuki Nakazawa 《Journal of agricultural and food chemistry》2002,50(1):53-58

For development of an indirect competitive enzyme-linked immunosorbent assay (ELISA) for the organophosphorus insecticide fenitrothion, the specificity of the antiserum R-3 generated with the bifunctional hapten, LysMNPA (2-[[[(3-methyl-4-nitrophenyl)oxy]methylcarbonyl]amino]-6-(2,4-dinitrophenyl)aminohexanoic acid) and the application to the residual analysis of some water samples were evaluated. At optimized ELISA conditions, the quantitative working range was from 1 to 39 ng/mL with a limit of detection of 0.3 ng/mL and an IC(50) value of 6 ng/mL. Cross-reactivity to structurally similar organophosphorus compounds and related chemicals was determined. The antiserum R-3 showed significant cross-reactivity with fenitrooxon and 3-methyl-4-nitrophenol, which have a 3-methyl-4-nitrophenoxy group as common structures, but showed relatively low cross-reactivity with other compounds. Each water sample (river water, tap water, purified water, and bottled water) had a matrix effect and was investigated by adding Tween 20 in the assay buffer. These four kinds of water samples were fortified with fenitrothion at several concentration levels and were directly analyzed with only dilution with an equal volume of antiserum solution. The mean recovery was 105.9%, and the mean coefficient of variation was 10.9%. The results suggested that the developed ELISA would be very suitable for a preliminary screening for fenitrothion in water samples at such low levels.  相似文献   

Anti-Helicobacter pylori agents from the cashew apple   总被引：1，自引：0，他引：1  

Kubo J  Lee JR  Kubo I 《Journal of agricultural and food chemistry》1999,47(2):533-537

Anacardic acids and (E)-2-hexenal characterized from the cashew Anacardium occidentale L. (Anacardiaceae) apple have been found to exhibit antibacterial activity against the Gram-negative bacterium Helicobacter pylori, which is now considered to cause acute gastritis. The same antibacterial compounds have also been found to inhibit urease (EC 3.5.1.5).  相似文献   

Kinetics of mushroom tyrosinase inhibition by quercetin   总被引：21，自引：0，他引：21  

Chen QX  Kubo I 《Journal of agricultural and food chemistry》2002,50(14):4108-4112

The effects of quercetin on the activity of mushroom tyrosinase were studied. The equilibrium constants for this inhibitor binding with the enzyme molecule were established. The inhibition mechanism obtained from Lineweaver-Burk plots show that quercetin is a competitive inhibitor. In the time course of the oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) catalyzed by the enzyme in the presence of different concentrations of quercetin, the rate decreased with increasing time until a straight line was approached. The inhibition of tyrosinase by quercetin is a slow and reversible reaction with residual enzyme activity. The microscopic rate constants were determined for the reaction of quercetin with the enzyme.  相似文献   

Cloned cows with short telomeres deliver healthy offspring with normal-length telomeres     

Miyashita N  Kubo Y  Yonai M  Kaneyama K  Saito N  Sawai K  Minamihashi A  Suzuki T  Kojima T  Nagai T 《The Journal of reproduction and development》2011,57(5):636-642

Dolly, the first mammal cloned from a somatic cell, had shorter telomeres than age-matched controls and died at an early age because of disease. To investigate longevity and lifetime performance in cloned animals, we produced cloned cows with short telomeres using oviductal epithelial cells as donor cells. At 5 years of age, despite the presence of short telomeres, all cloned cows delivered multiple healthy offspring following artificial insemination with conventionally processed spermatozoa from noncloned bulls, and their milk production was comparable to that of donor cows. Moreover, this study revealed that the offspring had normal-length telomeres in their leukocytes and major organs. Thus, cloned animals have normal functional germ lines, and therefore germ line function can completely restore telomere lengths in clone gametes by telomerase activity, resulting in healthy offspring with normal-length telomeres.  相似文献   

Differences in embryonic gene expression and quality indicate the benefit of epidermal growth factor receptor inhibitor during prematuration to improve competence in bovine oocytes     

Priscila Chediek Dall&#x;Acqua  Giovana Barros Nunes  Cíntia Rodrigues da Silva  Patrícia Kubo Fontes  Marcelo Fbio Gouveia Nogueira  Flvia Lombardi Lopes  Mrcia Marinho  Gisele Zoccal Mingoti 《Reproduction in domestic animals》2019,54(4):666-677

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