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41.
42.
Based on morphological evidence, we newly define the genus Stenotaenia Koch, 1847 (=Scnipaeus Bergsøe & Meinert, 1866; =Simophilus Silvestri, 1896; =Onychopodogaster Verhoeff, 1902; =Insigniporus Attems, 1903; =Notadenophilus Verhoeff, 1928; =Bithyniphilus Verhoeff, 1941; =Schizopleres Folkmanova, 1956; =Euronesogeophilus Matic, 1972; all syn. nov. ) as including the following 15 species: Stenotaenia linearis (Koch, 1835) (=Geophilus simplex Gervais, 1835; =Geophilus brevicornis Koch, 1837; =Scnipaeus foveolatus Bergsøe & Meinert, 1866; =Himantarium caldarium Meinert, 1886 syn. nov. ; =Geophilus (Geophilus) linearis var. polyporus Verhoeff, 1896 syn. nov. ; =Geophilus ormanyensis Attems, 1903 syn. nov. , after lectotype designation; =Insigniporus acuneli C?pu?e, 1968 syn. nov. ) from central and northern Europe; Stenotaenia frenum (Meinert, 1870) from northern Africa; Stenotaenia romana (Silvestri, 1895) (=Geophilus silvestrii Verhoeff, 1928 syn. nov. ) and Stenotaenia sorrentina (Attems, 1903) (=Geophilus forficularius Fanzago, 1881 syn. nov. ; =Geophilus linearis abbreviatus Verhoeff, 1925 syn. nov. ) from the Italian peninsula and Sardinia; Stenotaenia antecribellata (Verhoeff, 1898) (=Simophilus albanensis Attems, 1929 syn. nov. ), Stenotaenia cribelliger (Verhoeff, 1898), Stenotaenia palpiger (Attems, 1903), Stenotaenia rhodopensis (Kaczmarek, 1970), and Stenotaenia sturanyi (Attems, 1903) from the Balkan peninsula; Stenotaenia naxia (Verhoeff, 1901) (=Geophilus graecus Verhoeff, 1902) from the Aegean islands; Stenotaenia asiaeminoris (Verhoeff, 1898) and Stenotaenia bosporana (Verhoeff, 1941) from Anatolia; Stenotaenia giljarovi (Folkmanova, 1956) from western Caucasus; Stenotaenia fimbriata (Verhoeff, 1934) and Stenotaenia palaestina (Verhoeff, 1925) from Palestine; with the only exception of S. linearis, all of these binomens are comb. nov. In Stenotaenia, a strongly conserved overall morphology is matched by an unusual interspecific variation in both the body size of fully grown specimens (from 1.7 cm in S. romana to 7.7 cm in S. sturanyi) and the number of leg‐bearing segments (from 43 in male S. romana to 115 in female S. sturanyi). The number of segments correlates with maximum body size. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 153 , 253–286.  相似文献   
43.
In this work the modulation of the regio- and stereo-selective hydroxylation of testosterone by vinclozolin was studied in evaluating cocarcinogenic properties. Changes of cytochrome P450-(CYP)-catalysed drug metabolism was investigated in liver, kidney and lung microsomes of Swiss Albino CD1 mice of both sexes after single (625 or 1250 mg kg-1 b.w.) or repeated (daily 750 mg kg-1 b.w. for 3 days) i.p. administrations. Treatment of mice with a single dose of vinclozolin caused in a dose-dependent fashion from 2 1 to 14 1-fold increase in the 7-, 6- and 2-hydroxylations of testosterone in liver. Lower increase in extrahepatic tissues ranging from 2 3 to 8 1-fold for testosterone 6-, 16 -, 2- and 2- hydroxylase activity in the kidney or from 2 2 to 5 1-fold for 6-, 16 -, 16 - and 2- hydroxylase activity in the lung were observed. Repeated treatment with this fungicide did not substantially modify the extent and pattern of induction, the liver being the only tissue responsive (up to 7 6-fold increase, 7-hydroxylation) in both male and female. In the kidney (7-, 6-, 16 -, 2-, 7-hydroxylations) and lung (6-, 7-, 6-, 16 -, 16 - and 2- hydroxylations), a typical sex-dependent induction (up to 9 0-fold, 16 -hydroxylation in the lung, female) was achieved. In general, however, vinclozolin has a complex pattern of induction and suppression of CYP-dependent enzymes, as exemplified from the reduced expression of some hydroxylations depending upon dose, sex and organ considered. For example, after a single administration, 16 -hydroxylation was suppressed in liver (up to 78% loss in male, higher dose), whereas 16 -hydroxylation was reduced in kidney up to 50% in both sexes (at the higher dose). Glutathione S-transferase activity, measured as index of post-oxidative reactions, was markedly increased by vinclozolin in the liver (up to 5 2-fold, female) and kidney (up to 3 9-fold, female) but not in the lung. Because both phase I and phase II reactions were enhanced by vinclozolin treatment in liver and kidney, the ratio between activation/detoxification mechanisms was slightly affected. Conversely, this ratio was shifted toward activating mechanisms in the lung, sustaining, in part, the expression of certain type of tumours tissue-dependent. Taken together, these findings seem to indicate the cotoxic, cocarcinogenic and promoting potential of this fungicide.  相似文献   
44.
The uptake and release of 3H-labelled fusicoccin (FC) fed topea internode segments and the transport of [3H]FC in wholeplants and in excised parts of plants of pea, maize, and pumpkinhave been investigated. FC uptake showed three phases apparentlycorresponding to the penetration of FC: (1) into the free space;(2) into the cytoplasm; (3) into the vacuole. The first phase is a little thermosensitive and apparently includesadsorption binding to some free space component (cell surface?).The second and third phases are highly temperaturesensitiveand in part energy-dependent. However, no accumulation of FCagainst a concentration gradient is observed at high externalFC concentration. Accumulation at low concentration seems dueto the formation of a poorly exchangeable complex with somecell structure. The efflux of the FC penetrated within the cells is limitedby some highly temperature-sensitive process. A small fractionof the accumulated FC tends to be retained in the tissue, eitherbecause sequestered in some compartment or because bound tosome cellular component. FC transport in whole plants as well as in isolated plant partsseems to depend mainly on simple diffusion and on transportby mass flow in the xylem. Long distance transport of the toxinin pumpkin plants mainly occurs in the xylem, while the slowmovement in non-vascular tissues seems to depend on diffusioncombined with mass flow in the free space, and does not seemheavily influenced by metabolic factors.  相似文献   
45.
ABSTRACT. We observed different low salinity tolerances between two groups of populations of Euplotes crassus. After mating analysis, the less tolerant populations could be assigned to three mating groups. Two of them were separated by preconjugative barriers but both conjugated with a third one. A breeding test showed evidence of (potential) introgression mediated by this "bridging" group. On the other hand, the more tolerant populations formed a fourth mating group unable to conjugate with the others and characterized by distinct zymogram patterns. We conclude that natural introgression among the studied populations is not complete and that the species structure of E. crassus comprises intrafertile sets of populations among which gene flow may be difficult or virtually absent.  相似文献   
46.
Distribution of mobile organisms on near-continent islands is mainly shaped by factors operating over ecological rather geological time. However, the phylogeography of single species has the potential to expose historical factors at work. In the present study, West Mediterranean populations of the butterfly Maniola jurtina are studied using geometric morphometrics. The distribution of the two well established lineages ( Maniola jurtina jurtina in the Atlanto–Mediterranean area and Maniola jurtina janira in the Central–Eastern-Mediterranean area) on 12 islands and the adjoining continents are compared. The south-western lineage unexpectedly occurs on islands close to shores occupied by the eastern lineage. We have modelled the distribution of the lineages using three different hypotheses: (1) a contemporary isolation model, which predicts lineage occupancy of islands is linked to relative distances from neighbouring continental areas; (2) a refugial hypothesis, which predicts one lineage to be the ancestral one for the whole region studied, and then successively replaced over part of it; (3) a changing geography hypothesis, which predicts the two lineages to have evolved in their currently occupied areas, continuously sourcing islands subsequent to the Würm maximum glaciation. Of the three models, the refugial hypothesis is most highly correlated with the observed pattern, suggesting that Mediterranean islands may function as refugia during cold periods, much as the three mainland peninsulas of Iberia, Italy and Greece are known to have done. Thereafter, hybridization on the nearest and smallest islands has occurred, with the entire process supporting the notion of the joint influence of factors in ecological and geological time.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 98 , 677–692.  相似文献   
47.
Five species of sea skaters, genus Halobates Eschscholtz, are the only insects to have successfully colonized the open ocean. In addition, 38 species are found in sheltered coastal waters throughout tropical Indo-Pacific. The taxonomy of the genus is relatively well known, and the phylogeneuc relationships between extant species have recently been analysed (using cladistic methods). In the present paper, we describe the first fossil species of sea skaters, Halobates ruffoi sp. no v. from the Eocene deposit 'Pesciara di Bolca', in the province of Verona, northeastern Italy (geological age about 45 Myr). The significance of this fossil in setting the time scale for the reconstructed phylogeny and anagenesis of adaptive features of sea skaters, and in understanding the evolution and historical zoogeography of these marine insects is discussed.  相似文献   
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