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991.
992.
Shinichiro Maeshima Aiko Osawa Daisuke Nishio Yoshitake Hirano Koji Takeda Hiroshi Kigawa Yoshiyuki Sankai 《BMC neurology》2011,11(1):116
Background
Robotic devices are expected to be widely used in various applications including support for the independent mobility of the elderly with muscle weakness and people with impaired motor function as well as support for nursing care that involves heavy laborious work. We evaluated the effects of a hybrid assistive limb robot suit on the gait of stroke patients undergoing rehabilitation. 相似文献993.
994.
Akikazu Hatanaka Jiro Sekiya Tadahiko Kajiwara Koji Munechika 《Bioscience, biotechnology, and biochemistry》2013,77(11):2705-2710
The homogenate of tea seed cotyledons contained an inhibitor for C6-aldehyde formation from linoleic acid and linolenic acid by isolated tea chloroplasts. Seed homogenates of other plants, such as soybean, kidney bean, cucumber, Japanese radish and rice, also contained the inhibitor for C6-aldehyde formation. The inhibitor from tea seed and cucumber seed inhibited C6-aldehyde formation by the homogenate of cucumber hypocotyl. Hydroperoxides of linoleic acid detected were reduced when the tea seed inhibitor was added to the reaction mixture, but the enzyme activities of lipoxygenase and hydroperoxide lyase were not inhibited. This means that the inhibitor is a decomposer of fatty acid hydroperoxides as an intermediate of C6-aldehyde formation. The tea seed inhibitor was formed during the seed ripening and it was stable during the seed germination. These findings obtained here suggest that the inhibitor is widely present in plant seeds and inhibits C6-aldehyde formation by a variety of plant tissues. 相似文献
995.
Yutaka Tajima Zenzo Nagasawa Ichiro Tanabe Koji Kusaba Jutaro Tadano 《Microbiology and immunology》1994,38(8):639-648
We have recently found a factor (Factor T) in aged mixtures of tungstate and phosphate which greatly enhances the antibacterial effects of β-lactams on methicillin-resistant strains of staphylococcal species such as methicillin-resistant Staphylococcus aureus (MRSA), but shows only weak effects on methicillin-susceptible S. aureus and bacterial strains other than staphylococci. Factor T alone did not strongly inhibit cell metabolism and bacterial growth unless an excess amount was added. When Factor T was added to the culture medium beforehand, the growth of MRSA cells was rapidly suppressed just after addition of oxacillin (MPIPC). However, the growth of the cells was inhibited gradually when these two reagents were added in reverse order. For full expression of the enhancing effect, it seemed necessary for cells of MRSA strains to be incubated with Factor T for at least 2–3 hr. When the cells were washed after being sensitized by incubating them for 5 hr with Factor T, it took approximately 1 hr for the cells to recover their resistance to MPIPC. Factor T reduced the amount of penicillin-binding protein-2′ (PBP 2′), and thus sensitized the MRSA strains to β-lactams. 相似文献
996.
Plants have an ability to prevent chlorophyll accumulation, which would mask the bright flower color, in their petals. In contrast, leaves contain substantial amounts of chlorophyll, as it is essential for photosynthesis. The mechanisms of organ-specific chlorophyll accumulation are unknown. To identify factors that determine the chlorophyll content in petals, we compared the expression of genes related to chlorophyll metabolism in different stages of non-green (red and white) petals (very low chlorophyll content), pale-green petals (low chlorophyll content), and leaves (high chlorophyll content) of carnation (Dianthus caryophyllus L.). The expression of many genes encoding chlorophyll biosynthesis enzymes, in particular Mg-chelatase, was lower in non-green petals than in leaves. Non-green petals also showed higher expression of genes involved in chlorophyll degradation, including STAY-GREEN gene and pheophytinase. These data suggest that the absence of chlorophylls in carnation petals may be caused by the low rate of chlorophyll biosynthesis and high rate of degradation. Similar results were obtained by the analysis of Arabidopsis microarray data. In carnation, most genes related to chlorophyll biosynthesis were expressed at similar levels in pale-green petals and leaves, whereas the expression of chlorophyll catabolic genes was higher in pale-green petals than in leaves. Therefore, we hypothesize that the difference in chlorophyll content between non-green and pale-green petals is due to different levels of chlorophyll biosynthesis. Our study provides a basis for future molecular and genetic studies on organ-specific chlorophyll accumulation. 相似文献
997.
998.
Background
α-Synuclein is a Parkinson's-disease-related protein. It forms aggregates in vivo, and these aggregates cause cell cytotoxicity. Aggregation inhibitors are expected to reduce α-synuclein cytotoxicity, and an aggregation accelerator has recently been reported to reduce α-synuclein cytotoxicity. Therefore, amyloid aggregation modulating ligands are expected to serve as therapeutic medicines. 相似文献999.
Ken-ichi Setsuda Koji Tsuchida Hiroyuki Watanabe Yoshichika Kakei Yoshiki Yamada 《Journal of Ethology》1999,17(2):73-77
We surveyed male survival and reproductive performances associated with dimorphism in the Japanese horned beetleAllomyrina dichotoma L. in a secondary forest in 1996. Morphological comparisons between living marked and prey individuals indicated that the
larger horned males suffered higher predatory pressure than the smaller ones. The dominant predators of the beetles were suspected
to be 2 crow species. The small-horned males showed lower recapture rates than the large-horned ones. This suggested that
the former was more sensitive to disturbance, and/or dispersed more than the latter. Fighting behavior was rarely seen because
of the low population density of the beetles in the study area. These results suggested that the large-horned males suffer
not only the injury risk of intrasexual competition but also more predatory risk than the small-horned ones. 相似文献
1000.
Masato Kageyama Minoru Takagi Richard T. Parmley Masaaki Toda Hiroshi Hirayama Yoshihisa Toda 《The Histochemical journal》1985,17(1):93-103
Summary A modification of the tannic acid-metal salt method was applied as an ultrastructural stain for elastin. Thin sections of glutaraldehyde-fixed, embedded rat aorta and rabbit elastic cartilage, with and without osmication, were examined. Raising the pH of the tannic acid solution from 2.7 to 9.0 progressively increased the electron-density of elastic fibres and collagen fibrils in osmicated and unosmicated specimens. The maximum tannic acid staining of elastic fibres was observed in the pH range 7.0–9.0. Collagen staining, although less intense than that of elastic fibres, was also greatest in this pH range. Elastic fibres in osmicated specimens demonstrated the strongest tannic acid staining with a minimal increase in density of collagen and cell nuclei when compared to the unosmicated specimens. Sequential treatments of osmicated specimens with tannic acid pH 7.0–9.0, and uranyl acetate, pH 4.1, enhanced the density of the elastin intensely, increased collagen staining moderately, but hardly increased the density of nuclei and microfibrils. In elastase-digested osmicated specimens, all tannic acid (pH 7.0)-uranyl acetate-reactive elastin was selectively removed. These results demonstrate that all the neutral and alkaline tannic acid-uranyl acetate methods can be used as a postembedment stain for elastin specimens fixed in glutaraldehyde and osmium tetroxide. 相似文献