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131.
132.
Seventy-four primates species (24 genera of six families) were presented with a nylon rope and a wooden cube, and their subsequent manipulations were recorded in detail. Five hundreds and six manipulation patterns were distinguished on the basis of the actions performed, body-parts used and relations to other objects. Inter-specific comparisons revealed three groups: (1) lemurs, marmosets, spider monkeys and leaf-eaters; (2) Old World monkeys except leaf-eaters; and (3) cebus monkeys and apes. The first group had the smallest repertoire of manipulations, in which only a few types of actions and body-parts were involved. The second and third groups had more varied modes of manipulation. Actions such as Roll, Rub and Slide, and use of fingers characterized these groups. Except for the lesser ape, their manipulations were frequently related with other objects. Moreover, actions such as Drape, Drop, Strike, Swing and Throw were typical of the third group. The factors producing such inter-specific differences in manipulations and the relations to tool use are discussed.  相似文献   
133.
Nakamura  Kazuyo  Wada  Shinpei  Hatai  Kishio  Sugimoto  Takashi 《Mycoscience》1994,35(1):99-104
A fungal infection occurred in juvenile coonstripe shrimps,Pandalus hypsinotus, cultured at Hokkaido Institute of Mariculture, Hokkaido, Japan. The fungus was identified asLagenidium myophilum, the same fungus that had previously been isolated from the abdominal muscle of adult northern shrimps,Pandalus borealis, and larvae of the coonstripe shrimp. Histopathologically, numerous nonseptate hyphae were observed in the lesions, and melanized hemocytes were present within the blackened areas. The optimum temperature for growth of the present strain was 25–30°C, and the optimum NaCl concentration for growth was 0.5–1.0%. Its biological characteristics were compared with those ofLagenidium myophilum isolated from diseased larval coonstripe shrimp and adult northern shrimp. The fungus was pathogenic toward shrimps of the genusPandalus, which live in deep sea areas. The fungus could infect shrimps at various stages, from larva to adult.  相似文献   
134.
Abstract In order to determine whether non-elastase-producing strains of Pseudomonas aeruginosa such as N-10, PA103 and IFO3080 can express foreign elastase genes, we introduced elastase genes from P. aeruginosa IFO3455 (elastase-producing) as well as from PA103 and N-10 into non-elastase-producing P. aeruginosa strains. Results suggested that gene expression, secretion, and precursor processing systems of elastase were essentially normal in P. aeruginosa N-10 and IFO3080. Our studies using various elastase genes showed that both the elastase structural gene and 5'-upstream regions of P. aeruginosa PA103 were also normal. This was confirmed by the finding that P. aeruginosa N-10 and IFO3080 which carry the PA103 elastase gene produced elastase. Several deleted or chimeric genes were constructed using the 5'-upstream regions of elastase genes from P. aeruginosa N-10 or PA103 and studies of expression revealed that two individual DNA bases seem to be important in suppressing P. aeruginosa N-10 elastase gene expression. Possible reasons for the lack of elastase in these non-elastase-producing strains are discussed.  相似文献   
135.
7-O-Galloyl-(+)-catechin and 3-O-galloylprocyanidin B-3, along with gambiriins A-1 and B-3 and four polygalloylglucoses, have been isolated fro  相似文献   
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137.
Interestingly, only the D-form of firefly luciferin produces light by luciferin–luciferase (L–L) reaction. Certain firefly luciferin analogues with modified structures maintain bioluminescence (BL) activity; however, all L-form luciferin analogues show no BL activity. To this date, our group has developed luciferin analogues with moderate BL activity that produce light of various wavelengths. For in vivo bioluminescence imaging, one of the important factors for detection sensitivity is tissue permeability of the number of photons emitted by L–L reaction, and the wavelengths of light in the near-infrared (NIR) range (700–900 nm) are most appropriate for the purpose. Some NIR luciferin analogues by us had performance for in vivo experiments to make it possible to detect photons from deep target tissues in mice with high sensitivity, whereas only a few of them can produce NIR light by the L–L reactions with wild-type luciferase and/or mutant luciferase. Based on the structure–activity relationships, we designed and synthesized here a luciferin analogue with the 5-allyl-6-dimethylamino-2-naphthylethenyl moiety. This analogue exhibited NIR BL emissions with wild-type luciferase (λmax = 705 nm) and mutant luciferase AlaLuc (λmax = 655 nm).  相似文献   
138.
139.
Journal of Plant Research - Lianas have a huge influence on forest structure and function. However, it is unclear how the surrounding environment affects the establishment of liana seedlings in...  相似文献   
140.
Invasive plants apply new selection pressures on neighbor plant species by different means including allelopathy. Recent evidence shows allelopathy functions as remarkably influential mediator for invaders to be successful in their invaded range. However, few studies have determined whether native and non‐native species co‐occurring with invaders have evolved tolerance to allelopathy. In this study, we conducted germination and growth experiments to evaluate whether co‐occurring native Juncus pallidus and non‐native Lolium rigidum species may evolve tolerance to the allelochemicals induced by Cyanara cardunculus in Australian agricultural fields. The test species were germinated and grown in pots filled with collected invaded and uninvaded rhizosphere soil of C. cardunculus with and without activated carbon (AC). Additionally, a separate experiment was done to differentiate the direct effects of AC on the test species. The soil properties showed invaded rhizosphere soils had higher total phenolic and lower pH compared with uninvaded soils. We found significant reduction of germination percentage and seedling growth in terms of above‐ and belowground biomass, and maximum plant height and root length of native in the invaded rhizosphere soil of C. cardunculus, but little effect on non‐native grass species. Even soil manipulated with AC showed no significant differences in the measured parameters of non‐native except aboveground biomass. Taken together, the results indicate allelochemicals induced by C. cardunculus exert more suppressive effects on native than non‐native linking the coevolved tolerance of those.  相似文献   
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