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41.
The developmental morphology of the outer integument in the pendent orthotropous ovules of Amborella trichopoda (Amborellaceae) and Chloranthus serratus (Chloranthaceae) was studied. In both species the outer integument is semiannular at an early stage and becomes cup-shaped but dorsiventrally somewhat asymmetric at later stages. The outer integument, which is initiated first on the concave and lateral sides of the ovule, differs from that of the anatropous ovules of other basal families with the outer integument semiannular at an early stage or throughout development. The bilateral symmetry of the outer integument is shared by these orthotropous and anatropous ovules. The developmental pattern of the outer integument and ovule incurving characterize the ovule of the Amborellaceae and Chloranthaceae, which is not equivalent to typical orthotropous ovules of eudicots. A phylogenetic analysis of ovule characters in basal angiosperms suggests that anatropous ovules with cup-shaped outer integuments and orthotropous ovules were derived independently in several clades and that the ovules of Amborella and Chloranthus might also be derivative.  相似文献   
42.
The river‐weed family Podostemaceae (c. 300 species in c. 54 genera) shows a number of morphological innovations to be adapted to its unusual aquatic habitat, and its unique or rare bauplan features have been reflected in the traditional (i.e. non‐molecular) classification recognizing numerous monotypic or oligospecific genera. The infrasubfamilial relationships of many genera remained unclear. The present study used molecular phylogenetic analysis of matK sequences for 657 samples (c. 132 species/c. 43 genera). The family was traditionally divided into three subfamilies (Podostemoideae, Tristichoideae and Weddellinoideae). American Podostemoideae were shown to be polyphyletic and divided into four clades, i.e. Ceratolacis, Diamantina, Podostemum and all other genera. Among the podostemoid clades, Diamantina was the first branching clade and a clade comprising Mourera and the Apinagia subclade was then sister to the remainder of the New World and Old World Podostemoideae with low statistic supports. The Old World Podostemoideae comprised four monophyletic clades, i.e. two African clades, one Madagascan clade and one Asian clade, although the relationships among these clades and American Ceratolacis and Podostemum were poorly resolved. African Podostemoideae were polyphyletic, with Saxicolella pro parte being weakly supported as sister to the remaining Old World Podostemoideae plus Ceratolacis and Podostemum. In contrast to the American and African clades, monophyly of four Asian subclades was well supported. Plants of Tristicha (Tristichoideae) and of Weddellina (Weddellinoideae), which are currently treated as monospecific, had great matK differentiation equivalent to at least interspecific variation. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169 , 461–492.  相似文献   
43.
Xanthine-oxidizing activities in the chick tissues were measured by a couple of assay procedures during development of chick embryo. With the usual assay using pterine and NAD+, no detectable level of XDH activity was observed in the liver and little in the duodenum before hatching, whereas an appreciable activity was detected in the kidney of chick embryo. When assayed with xanthine and dichlorophenol indophenol, an XDH-like enzyme activity was significantly detected in the embryonic liver, while no further enhancement of the activity was detected in the kidney and duodenum. Electrophoregrams obtained with samples from various developmental stages, followed by activity staining with tetrazolium dye, supported the above results and revealed that the embryonic XDH-like enzyme is not distinguishable from XDH of adult tissue in molecular size. This XDH-like enzyme, pre-existing in the liver before hatching, however, exhibited no cross reaction with antibody against intact XDH. The nature of this material was discussed in comparison with deflavinated XDH.  相似文献   
44.
In this study we explored the possible application of MAT-1, which has been established as a monoclonal antibody against human tyrosinase, for detection of mouse tyrosinase. The MAT-1 reacted with B16 mouse melanoma cells, but not with tyrosinase-negative NIH-3T3 mouse fibroblasts. In western blot analysis of the large granule fraction (LGF) of B16 cells, MAT-1 detected a single protein of 80 kDa, whose size was close to that of human tyrosinase detected with MAT-1 in extracts of human melanocytes. Furthermore, the 80 kDa band that was detected with MAT-1 in the LGF of B16 cells was also detected by DOPA reaction. In order to confirm that the protein detected with MAT-1 is tyrosinase, a transient expression assay was carried out. When mouse tyrosinase or mouse tyrosinase-related protein 1, which shares high homology with human tyrosinase, was transiently expressed in tyrosinase-negative K1735 mouse melanoma cells by cDNA transfection, MAT-1 reacted only with the cells expressing mouse tyrosinase. These results indicate that MAT-1 specifically reacts with mouse tyrosinase.  相似文献   
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46.
Veratrum album subsp. oxysepalum is an andromonoecious perennial woodland herb. In the present study, to clarify the essential life-history characteristics of this species, sexual reproduction was examined and breeding experiments were carried out along with observations of floral visitors in the field. The results of the breeding experiments showed that this species has a high level of self-incompatibility. As various Coleoptera and Diptera visited the flowers, the seed production of V. album subsp. oxysepalum possibly depends on outcrossing pollination by insects.  相似文献   
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A forest-stream trophic link was examined by stable carbon isotope analyses which evaluated the relationship of aquatic insects emerging from a stream to the diets of web-building spiders. Spiders, aquatic and terrestrial prey, and basal resources of forest and stream food webs were collected in a deciduous forest along a Japanese headwater stream during May and July 2001. The 13C analyses suggested that riparian tetragnathid spiders relied on aquatic insects and that the monthly variation of such dependence is partly associated with the seasonal dynamics of aquatic insect abundance in the riparian forest. Similarly, linyphiid spiders in the riparian forest exhibited 13C values similar to aquatic prey in May. However, their 13C values were close to terrestrial prey in both riparian and upland (150m away from the stream) forests during June to July, suggesting the seasonal incorporation of stream-derived carbon into their tissue. In contrast, araneid spiders relied on terrestrial prey in both riparian and upland forests throughout the study period. These isotopic results were consistent with a previous study that reported seasonal variation in the aquatic prey contribution to total web contents for each spider group in this forest, implying that spiders assimilate trapped prey and that aquatic insect flux indeed contributes to the energetics of riparian tetragnathid and linyphiid spiders.  相似文献   
50.
IutroduCtionTertiaryrodentfossilshavebeenrarelyfoundinJapan.TomidaandSetoguchi(l994)reportedninesPecimensfromtheEarlyMiocenesedimentsintheMisunamiandKhnibasins,GifuPrefecture,centralJapanwithabridreviewoftheTertiaryrodentsfromtheJapaneseIslands.Accordingtotheirreport,therodentfaunainthesebasinsiscomposedofthesPechoensreferredtoCastoridae,Eomyidaeandunidentifiedrodents.Amongthem,CastoridaeincludesYoungoNersinensis,acharacteristicChineseMiocenebeaver.TheoccurrenceofYoungofthersinensiss…  相似文献   
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