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71.
72.
We investigated the impact of high solar irradiance and elevated temperature on carbon gain by two, co-occurring, sun-adapted, dwarf shrub species, Planchonella obovata var. dubia (Koidz.) Hatusima and Hibiscus glaber Matsumura, growing on sun-exposed ridges in the Bonin Islands, in the subtropical Pacific Ocean. Planchonella had steeply inclined, longer lived, sclerophyllous leaves, whereas Hibiscus has thinner, more horizontally oriented, and shorter lived leaves. We tested the hypothesis that leaf physiological tolerance to high light is lower in Planchonella than in Hibiscus. Under relatively high irradiances (photosynthetic photon flux density, PPFD, > 500 micromol m(-2) s(-1)), net photosynthetic rate (P(n)) was about 8.0 and 0.4 micromol m(-2) s(-1) in mature and young leaves of Planchonella, and about 12.4 and 10.3 micromol m(-2) s(-1) in mature and young leaves of Hibiscus, respectively. Both P(n) and photosystem II (PSII) quantum yield at a given PPFD were lower in Planchonella than in Hibiscus, whereas non-photochemical quenching (NPQ) at a given PPFD was higher in Planchonella. When leaf discs were exposed to high light (1900 micromol m(-2) s(-1) PPFD) at 37, 40 or 43 degrees C for 3 h, the recovery of PSII quantum yield (F(v)/F(m)) in the following 60-min dark period was slower in Planchonella than in Hibiscus, indicating that the ability of PSII to tolerate high light and high temperature was less in Planchonella than in Hibiscus. We postulate that there is a linkage between leaf display and leaf photochemical ability in sun-adapted shrub species. 相似文献
73.
Four lignans — pinoresinol, lariciresinol, secoisolariciresinol, matairesinol — were isolated from each ofDaphne odora andDaphne genkwa (Thymelaeaceae). Matairesinol isolated from both plants was optically pure (>99% e.e.) and dextrorotatory. Pinoresinol and lariciresinol isolated from the plants were not optically pure, and their enantiomeric compositions ranged from 88% to 95% e.e. in favor of (–)-enantiomers. As for secoisolariciresinol, the one fromD. odora was optically pure [(+)-enantiomer, >99% e.e.], and that fromD. genkwa was 97% e.e. in favor of the (+)-enantiomer. Lignan-synthesizing enzyme activity was detected from a Thymelaeaceae plant for the first time; cell-free extracts fromD. genkwa catalyzed the formation of (–)-lariciresinol (23% e.e.) from racemic (±)-pinoresinols. The stereochemistry of the enzymatic reaction is discussed in relation to the stereochemical features of the isolated lignans.Parts of this report were presented at the 42nd Lignin Symposium, Sapporo, October 1997; 48th Annual Meeting of the Japan Wood Research Society, Shizuoka, April 1998; and 49th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1999 相似文献
74.
Fukasawa T Murashima K Matsumoto I Hosono A Ohara H Nojiri C Koga J Kubota H Kanegae M Kaminogawa S Abe K Kono T 《Journal of agricultural and food chemistry》2007,55(8):3174-3179
Prebiotic fructooligosaccharides are noted for their intestinal immunodulating effects, and the identification of markers for the effects is a matter of great concern. This study aimed to identify marker genes for physiological effects of a particular fructooligosaccharide (FOS) on a host animal and also to define the target of its function in the small intestine. DNA microarray technology was used to screen candidate marker genes, and comprehensive changes in gene expressions in the ileum of mice fed with FOS were investigated. One of the major physiological effects of FOS was intestinal immunomodulation. Marker genes were then identified for major histocompatibility complex classes I and II, interferon, and phosphatidylinositol metabolites. Also, the ileum was segmented into Peyer's patch (PP) and the other ileal organ (DeltaPP), and these were analyzed by quantitative RT-PCR method, with the result that the site for recognizing the FOS function was the DeltaPP rather than the PP. This is the first paper showing the markers for the physiological effects of FOS in the small intestine at gene expression level. Applying these marker genes would make it possible to clarify the mechanisms of how the administration of dietary FOS and associated changes in the intestinal environment are recognized by host organisms as well as how its immunomodulating effects are expressed in the body. 相似文献
75.
In this report, we present a series of cases of thermal burns (scalds) in dogs resulting from exposure to hot water from a garden hose that had been lying in the sun. These dogs typically inhabited the southern and western regions of the USA, where the recorded high temperatures often exceed 32°C (90°F) during the warm summer months. Dogs with thermal scald injury in these cases presented with linear thermal burns along the dorsum, in addition to a variety of other macroscopic lesions that were dependent upon the degree of burn exposure and ranged from local erythema to ulcerated, necrotic and sloughing skin. Chronic, healed wounds were often alopecic, with markedly thickened skin and characteristically smooth and glassy scar tissue formation. Histologically, the lesions of thermal scald injury in these dogs were indistinguishable from any other second or third degree burn, and consisted of full-thickness dermal and epidermal necrosis with occasional fibrinoid necrosis of vessel walls, vasculitis and intravascular thrombosis. Here, we closely examine 10 cases of dogs with dorsal thermal burns collected from Texas, Arizona, California, Utah, Nevada, Indiana, Michigan and North Carolina and propose the term 'garden hose scalding syndrome (GHS)' to describe this unique type of scald injury. 相似文献
76.
Staphylococcus pseudintermedius strains were isolated from healthy dogs and dogs with pyoderma in 2000-2002 and 2009. All the isolates from dogs with pyoderma in 1999-2000 and from healthy dogs in 2000-2002 and 2009 were susceptible to cefalexin and/or other cephalosporins and oxacillin. However, 7.1-12.5 and 11.4% of S. pseudintermedius isolates from dogs with pyoderma in 2009 were resistant to cephalosporins and oxacillin, respectively. All S. pseudintermedius isolates from dogs with pyoderma in 1999-2000 and those from healthy dogs in 2000-2002 were susceptible to fluoroquinolones; however, 50% of the S. pseudintermedius strains isolated from dogs with pyoderma in 2009 and 30% of the S. pseudintermedius strains isolated from healthy dogs in 2009 were resistant to fluoroquinolones. Of the 21 oxacillin-resistant S. pseudintermedius (MRSP) isolates, 11 carried SCCmec type V and 10 carried hybrid SCCmec types II-III. Staphylococcus pseudintermedius strains that were resistant to only one of three fluoroquinolones had a mutation in the quinolone resistance determination region of grlA, whereas S. pseudintermedius strains that were resistant to two or more fluoroquinolones had mutations in the quinolone resistance determination regions of both grlA and gyrA. 相似文献
77.
Shimode S Miyazawa T Kobayashi T Sato H Tanabe T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(2):235-239
Interferon-stimulated gene 15 (ISG15) is one of the type I interferon-inducible proteins. Addition of ISG15 known as ISGylation is an ubiquitin-like posttranslational modification. Coexpression of ISG15 and ubiquitin-activating enzyme E1-like protein (UBE1L) is required to induce ISGylation. Previously, we identified feline ISG15 gene and found that the capsid protein of feline immunodeficiency virus was ISGylated in vitro by treatment with feline interferon-ω. In this study, we cloned feline UBE1L (FeUBE1L) gene to further study the mechanism of the antiviral activities induced by ISGylation. Sequencing analysis revealed that active sites of FeUBE1L were highly conserved. These data suggest that FeUBE1L has an enzymatic activity. Further, expression of FeUBE1L was induced in feline cell lines by treatment with feline interferon-ω and ovine interferon-τ. 相似文献
78.
Okumura Yutaka Matsuoka Hiromi Arakawa Hisayuki Tokanai Fuyuki Suzuki Atsushi Irizuki Toshiaki Kajita Hiroto Hara Motoyuki 《Fisheries Science》2021,87(1):121-130
Fisheries Science - Two sediment cores were collected from two sites in Nagatsura-Ura Lagoon, the mouth of which was destroyed in the 2011 Tohoku-oki tsunami. Although sediment conditions differed... 相似文献
79.
80.
Food colorants including rose bengal, erythrosine B, phloxine B and cochineal extracts were added to Alaska pollack Theragra chalcogramma surimi which was previously added with methyl linoleate (MeLe) or ethyl eicosapentaenoate (EPA Et). All the surimi were exposed
to a 100-watt light tungsten bulb (4500 lux) in a cold room at 5°C. Four isomeric hydroperoxides, including 13-cis, trans-, 13-trans, trans-, 9-trans,cis- and 9-trans,trans-MeLe hydroperoxides, were generated by oxidation of MeLe added to surimi with and without cochineal extracts after exposure
to light for several hours. For the surimi containing rose bengal, erythrosine B and phloxine B, extracted lipids contained
not only the above four hydroperoxide isomers but also 12-cis,trans-as well as 10-trans,cis- MeLe hydroperoxides. EPA Et added to surimi which contained rose bengal, erythrosine B and phloxine B generated characteristic
isomeric hydroperoxides, including 6-cis,trans- and 17-cis,trans-EPA Et hydroperoxides due to 1O2 mediated oxidation. The pro-oxidative potentials of four food colorants in surimi against added EPA Et or MeLe increased
as the order of cochineal extracts < phloxine B<erythrosine B<rose bengal. These results clearly demonstrated that the addition
of certain food colorants to surimi accelerated 1O2 mediated lipid oxidation to result in the generation of characteristic hydroperoxide isomers. 相似文献