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Thirteen species in four genera of mites of the family Macrochelidae phoretic on dung beetles were collected in the eastern part of the Lesser Sunda Islands, Indonesia, providing the first record of the family for that area. Of these, two species, Macrocheles entetiensis Hartini and Takaku, sp. nov. and Macrocheles sumbaensis Hartini and Takaku, sp. nov., are new to science. The remaining 11 species are Glyptholaspis fimicola, Holostaspella bifoliata, Macrocheles baliensis, Macrocheles sp. aff. glaber, M. hallidayi, M. kraepelini, M. krantzi, M. limue, M. merdarius, M. oigru and Neopodocinum sinicum.  相似文献   
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Cultered hepatic stellate cells were induced to elongate long, multipolar cellular processes by interstitial collagen gel used as a substratum, as compared to flattened or round cell shapes on polystyrene surface or on Matrigel containing the basement membrane components, respectively. The process induction was inhibited by several reagents as follows: (1) anti-integrin α2 antibody; (2) an oligopeptide, DGEA, an integrin-binding sequence in type I collagen molecule; (3) wortmannin, a phosphatidylinositol 3-kinase inhibitor. Protein tyrosine phosphorylation was enhanced throughout cells including cellular processes by culturing on type I collagen gel. Dual fluorescence staining showed that the core of the processes contained microtubules, whereas the periphery of the processes comprised fibrillar actin. Thus, the process extension was found to depend on integrin-binding to type I collagen fibres, followed by signal transduction and cytoskeleton assembly. The cellular processes included interstitial collagenase and vitamin A-containing lipid droplets. The lipid droplets and vitamin A-autofluorescence were increased by retinyl acetate addition to the culture medium, suggesting an important role of processes in hepatic stellate cell function.  相似文献   
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The three-dimensional structure of the extracellular substratum was found to regulate reversibly the morphology, proliferation and collagen synthesis of perisinusoidal stellate cells (lipocytes, i.e. fat-storing ‘Ito’ cells). On non-coated polystyrene and type I collagen-coated culture dishes, the cells spread well and extended their cellular processes. On the surface of type I collagen gels, the cells gathered and formed a mesh-like structure. However, in type I collagen gel where the cells were surrounded by type I collagen three-dimensionally, the cells extended their fine cellular processes and resembled the star-shaped stellate cells seenin vivo. The cell proliferation was more prominent in culture dishes coated with type I collagen or in polystyrene culture dishes than on or in type I collagen gels. The collagen synthesis was affected in the same manner. These data indicate that the nature and the three-dimensional structure of the extracellular matrix (ECM) can regulate morphology, proliferation and functions of the perisinusoidal stellate cells. In order to examine the reversibility of these regulations, we liberated cultured cells with trypsin or with purified bacterial collagenase and re-seeded them onto or into each substratum. The cells changed their shape, rate of proliferation and collagen synthesis according to each new substratum. These results indicate that the three-dimensional structure of ECM reversibly regulates the morphology, proliferation rate and functions of the perisinusoidal stellate cells.  相似文献   
15.
Unfertilized sea urchin eggs were pre-treated with 2–10 mM procaine sea water for 10 min and then fertilized 5 min later. These eggs hatched about 1–1.5 hr earlier than the control eggs. This acceleration of hatching seems to be the result of a reduction in the individual cleavage cycles. In the second series of experiments, eggs were inseminated at 5, 30 and 60 min after the procaine treatments. In this case, the rate of accelerated cleavage decreased gradually, as the intervals between the treatments and insemination were extended. Next, the minimum time-length of procaine treatment to accelerate cleavage was determined. When eggs were immersed in procaine for 1 min, cleavage was accelerated as in the case of 10 min-treatment, although acceleration to the same degree required higher concentrations of procaine solution. When fertilized eggs were post-treated with procaine, cleavage was also accelerated, but both the rate of acceleration and the effective concentrations decreased with time after fertilization.  相似文献   
16.
Of the 22 species of Ropalidia occurring in Australia, only R. plebeiana is distributed in temperate areas. This wasp is abundant in the south‐eastern coastal regions of Australia, where it forms huge nest aggregations. Based on our observations in late autumn and early spring, as well as information in the literature, we outline the colony cycle of R. plebeiana in the south‐eastern coastal area of New South Wales. The nesting period lasts for approximately 9.5 months, which is unusually long for temperate polistine wasps. Most foundresses seem to return to their natal nests in early spring (mid‐August to early September) to start their own colonies by reusing pre‐existing nest combs, and the pre‐emergence stage (before the emergence of the first adult brood) lasts for approximately 3.5 months. Reproductives (gynes and males) start to emerge as adults in early March, and the reproductive‐producing period lasts until the end of May. Both the pre‐emergence stage and the reproductive‐producing period are much longer than in other temperate polistine wasps, which is discussed in terms of fluctuating temperature conditions in the area and the formation of nest aggregations, a peculiar habit for temperate populations of R. plebeiana.  相似文献   
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The activity of shikimate: NADP oxidoreductase [EC 1. 1. 1.25] in sweet potato root tissue increased soon after slicing.Enzyme preparations obtained from both sliced tissue and fromfresh tissue probably contained a single enzyme component, andthey showed identical chromatographical behaviour. Km values of the enzyme for NADP and shikimate were 1.0x10–4Mand 1.3 x 10–3M, respectively. Enzyme activity was potentlyinhibited by SH-inhibitors such as p-chloromercuribenzoate andoxidized glutathione. Enzyme activity was affected neither by mononucleotides suchas ATP, ADP and AMP, divalent cations, Mg++, Ca++ and Mn++,nor by metabolites such as tryptophan, phenylalanine, tyrosineand t-cinnamic acid which are involved in aromatic compoundsyntheses. The enzyme rapidly lost its activity. This inactivation reactionshowed a time course consisting of two steps of the first-orderreaction. The inactivated enzyme preparation was not reactivatedby thiol compounds such as cysteine, 2-mercaptoethanol and glutathione,although these reagents, to a certain extent, protected theenzyme from inactivation. The results suggest that denaturationof the enzyme protein was involved in inactivation of the enzyme. 1Part 74 of the phytopathological chemistry of sweet potatowith black rot and injury. 2Present address: Department of Biology, Faculty of Science,Tokyo Metropolitan University, Setagaya-ku, Tokyo. (Received August 5, 1968; )  相似文献   
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A total of 56 morphological characters were analyzed for 53 cirrospiline species that represent all of the 17 described genera of the tribe. The other taxa of the Eulophinae included in the analysis were six species of six representative genera in the tribe Eulophini, a species of Elasmus (the only genus comprising the tribe Elasmini), and a species of Trichospilus (unplaced). Trichospilus and two of the six genera of Eulophini examined were placed within Cirrospilini. Monophyly of Cirrospilini (when these two genera of Eulophini and Trichospilus are included) and of the cirrospiline genera for which more than one species were examined was supported, but the relationships between the genera were poorly resolved. An exception was Cirrospilus, the largest genus in the Cirrospilini, monophyly of which was not supported to any extent.  相似文献   
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