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951.
We determined the flight capabilities and feeding habits of adults of nine silphine beetle species and illustrated their relationship.
We examined the silphine beetles for the presence or absence of flight muscles and estimated their feeding habits by comparing
the carbon and nitrogen stable isotope ratios for them with those of necrophagous nicrophorine species and carnivorous carabine
species. Three species (Silpha longicornis, S. perforata and Phosphuga atrata) completely lacked individuals with flight muscles, and one species (Eusilpha japonica) showed flight muscle dimorphism. Stable isotope analysis suggested that these species were carnivores, mainly feeding on
soil invertebrates. Most flight species showed higher isotopic ratios than the flightless species. Some of them have isotopic
ratios close to those of the nicrophorine species, suggesting that these species mainly feed on vertebrate carcasses. Flightless
silphine species would have limited ability to search for patchy and unpredictable carcass resources. Further studies are
necessary to understand the adaptive evolution of flight capability and the feeding habits in this group. 相似文献
952.
953.
954.
An aspartic proteinase was partially purified from PSII membranesof spinach. The 23-kDa protein of PSII was resistant to theproteinase when in its native form but became susceptible uponmodification by p-chloromercuriphenylsulfonic acid (pCMPS),upon incubation at pH 3, and upon incubation in dilute SDS.Conformational changes caused by pCMPS seemed to be restrictedto a localized region since the modified protein reconstitutedthe water-oxidizing complex with slightly less efficiency ascompared with the untreated protein. Under the three proteolyticconditions, cleavage occurred at the Asn-58-Leu-59 bond, suggestingthat the protein underwent similar conformational changes ineach case. Dithiothreitol, dialysis at pH 7, and neutral detergentssuppressed the facilitative effects of pCMPS, pH 3, and SDSon proteolysis, respectively. With the reversible changes insusceptibility, reversible changes in circular dichroism ofthe protein also occurred at 200208 nm. These observationsindicate that the conformational changes are reversible andthe renaturation of the substrate was associated with the suppressionof the susceptibility. These results suggest that the scissilebond becomes reversibly exposed and susceptible to the proteinasein response to environmental changes. (Received November 23, 1994; Accepted February 7, 1995) 相似文献
955.
Seiji Yamasaki Norimichi Kan Keiichi Mise Takehisa Harada You Ichinose Yoshio Moriguchi Hiroshi Kodama Kohei Satoh Kazuhisa Ohgaki Takayoshi Tobe 《Biotherapy》1993,6(1):63-71
In patients with Stage II or III breast cancer and in patients with liver metastases from breast cancer, we examined cellular interaction in the cytotoxicity against autologous tumor cells by interleukin-2(IL-2)-cultured lymphocytes (CL) and fresh peripheral blood lymphocytes (FPBL) treated with immunochemotherapy including OK-432 and cyclophosphamide. In flow cytometric analysis, CD8 + CD11b+ and CD16+ cells significantly decreased after immuno-chemotherapy in both groups of patients. A protocol study in Stage II or III breast cancer patients showed suppressive activity of FPBL on the cytotoxic activity of CL in 3/9 of the non-treatment group but no suppressive activity and enhancing activity in 3/7 in the immuno-chemotherapy group. Moreover, in 19 patients with liver metastases from breast cancer treated with immuno-chemotherapy including adoptive immunotherapy, FPBL in 6/19 showed enhancing activity, and in 8/19 suppressive activity in the lysis of autologous tumor cells. In assaysin vitro using autologous and allogeneic tumor cells, FPBL showed a partial specificity in cellular interaction against autologous tumor cells. CD4-depleted FPBL inhibited cytotoxicity of CL, while CD8-depleted FPBL enhanced cytotoxicity of CL in patients with liver metastases. These results suggest that immuno-chemotherapy eliminates the suppressive population in FPBL and may induce tumor regression if combined with adoptive immunotherapy using CL.Abbreviations IL-2
interleukin-2
- CL
IL-2-cultured lymphocytes
- FPBL
fresh peripheral blood lymphocytes
- AIT
adoptive immunotherapy 相似文献
956.
957.
Preferences for paper bedding material of the laboratory mice. 总被引:3,自引:0,他引:3
Akio Ago Tatuo Gonda Mayumi Takechi Takashi Takeuchi Kohei Kawakami 《Experimental Animals》2002,51(2):157-161
In order to identify indicators of the preferences for bedding materials, the paper bedding material preferences of laboratory mice were investigated in the present study. Four cages, each containing a different structure of paper bedding material were connected to allow free access to each cage. The preferences for paper bedding materials of laboratory mice were judged by the differences in the length of stay and sleep in each cage. The mice preferred the bedding material that allowed them to easily hide and build nests and was soft. We conclude that the comfort and well-being of laboratory mice can be increased through the appropriate selection of bedding material. 相似文献
958.
Masakazu Umezawa Toshihiro Sera Hideo Yokota Maho Takematsu Masahiko Morita Gil Yeroslavsky Masao Kamimura Kohei Soga 《Journal of biophotonics》2020,13(8)
This study aims to develop a novel cross‐sectional imaging of fluorescence in over‐1000 nm near‐infrared (OTN‐NIR), which allows in vivo deep imaging, using computed tomography (CT) system. Cylindrical specimens of composite of OTN‐NIR fluorophore, NaGdF4 co‐doped with Yb3+ and Ho3+ (ex: 980 nm, em: 1150 nm), were embedded in cubic agar (10.5–12 mm) or in the peritoneal cavity of mice and placed on a rotatable stage. When the fluorescence from inside of the samples was serially captured from multiple angles, the images were disrupted by the reflection and refraction of emitted light on the sample‐air interface. Immersing the sample into water filled in a rectangular bath suppressed the disruption at the interface and successfully reconstructed the position and concentration of OTN‐NIR fluorophores on the cross‐sectional images using a CT technique. This is promising as a novel three‐dimensional imaging technique for OTN‐NIR fluorescent image projections of small animals captured from multiple angles. 相似文献
959.
Susan L. Makris Howard M. Solomon Ruth Clark Kohei Shiota Stephane Barbellion Jochen Buschmann Makoto Ema Michio Fujiwara Konstanze Grote Keith P. Hazelden Kok Wah Hew Masao Horimoto Yojiro Ooshima Meg Parkinson L. David Wise 《Birth defects research. Part B, Developmental and reproductive toxicology》2009,86(4):227-327
960.
Toshihiko Kakiuchi Muneaki Matsuo Hiroyoshi Endo Yasuhisa Sakata Motohiro Esaki Takahiro Noda Ichiro Imamura Kazutoshi Hashiguchi Shinichi Ogata Yasuhiko Fujioka Keiichiro Hanada Kayoko Fukuda Masaya Yoshimura Tetsuro Kajiwara Kentaroh Yamamoto Daisuke Yamaguchi Hiroharu Kawakubo Taro Akashi Michihiro Sumino Keiji Matsunaga Eriko Muro Atsuo Kuwahara Kazuto Taniguchi Koji Fukuyama Akira Watanabe Ayako Takamori Masumi Okuda Kohei Yamanouchi Kazuma Fujimoto 《Helicobacter》2021,26(2):e12776