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1.
Alvarez, J. and Guerra, H. 1985. Biochemical and morphologicalchanges in protein bodies during germination of lentil seeds.—J.exp. BoL 36: 1296–1303. Protein bodies were extracted from lentil (Lens culinaris Medilk,var. castellana) seeds. Proteins from the protein bodies weredegraded during the first 7 d of germination. In some casesthis mobilization of proteins was accompanied by fusion of theprotein bodies into a large central vacuole. The loss of proteinswas paralleled by an increase in the activity of an enzyme systemthat hydrolysed casein. The different kinds of protein bodiesexhibited structural differences; some displayed uniform material,others coagulated or semi-coagulated material and the thirdkind displayed inclusions. Key words: Lentil, protein bodies, seed germination  相似文献   
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Eight novel polymorphic microsatellite loci are presented for the endangered land snail Trichia caelata, a rare species endemic to the Northwestern Jura mountains, Switzerland. The number of alleles per locus ranged from six to 17. At seven loci, the expected heterozygosity differed significantly from observed heterozygosity. No evidence for linkage disequilibrium was detected between locus pairs. We are currently using these markers to investigate the genetic population structure of T. caelata in its restricted distribution area.  相似文献   
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Brunton, C. Howard C. & Alvarez, Fernando 1989 07 15: The relationship between major lamellae and epithelial regressions in some articulate brachiopods. Lethaia , Vol. 22, pp. 247–250. Oslo. ISSN 0024–1164.
Hiller (1988, Lethaia , Vol. 212) proposed three relationships between the secretory epithelium of articulate brachiopods and the shell surface ornamentations of growth lines, lamellae and spines. None of his models satisfy the growth of strongly lamellose athyrid shells and we propose a fourth involving strong regressions effecting both primary and secondary shell layers. In Recent Tegulorhynchia we suggest a growth function for the 'frayed' shell of Hiller occurring immediately in front of the spines.  相似文献   
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Abstract.  1. Molecular techniques have greatly added to the number of known sympatric cryptic species in insects. Ecological differences between these newly distinguished species are little explored, but niches often appear to overlap strongly. These cases are good models for exploring new ideas about species coexistence and community structure.
2.  Acanthoscelides obtectus and A. obvelatus are two sister species of bean bruchids, which have been confused until the last decade. One important ecological difference between them has emerged, however: A. obtectus is multivoltine and now distributed worldwide, whereas A. obvelatus is univoltine and restricted to Mesoamerica. Where their ranges overlap, the two species share the same host plants and larvae can sometimes complete development in the same seed.
3. The analysis of 27 622 Mexican individuals of the two species in 2001-2002 and 2002-2003 indicates that their niches overlap, but are differentiated with respect to altitude and the kind of beans (wild vs. domesticated). The principal patterns in their relative abundance in different habitats, and at different seasons, were constant from one year to the next.
4. As sympatry of these species seems to be of recent origin, the observed niche differentiation may not have evolved in response to competition, but could instead be the consequence of physiological differences, evolved independently in each species in allopatry, that pre-adapted them for different altitudes and kinds of resources.
5. The combination of biological and historical factors thus appears to allow these two sibling species to coexist in sympatry, despite their broadly overlapping ecological niches.  相似文献   
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WE have already reported a cytospecific effect of serotonin in enhancing the growth of fibroblasts in vitro1, apparently by shortening the lag phase. We have now investigated this effect and the kinetics of cell growth in order to provide information about the mechanism of action of serotonin.  相似文献   
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A new species of cephalaspidean gastropod from MediterraneanSea (West Naples Gulf, Italy) is described. This species, Haminaeafusari, is characterised mainly by the presence of short parapodiallobes, which cover only the anterolateral parts of the shell;the prostatic gland has two lobes separated by a narrow andcylindrical zone; the lateral teeth of the radula are all smooth;the penis has a triangular section at the apical zone and asmall sharpened tip; and the spawn is horse-shoe-shaped or coiledin a single spiral. This species is compared with all the Europeanspecies of the genus and a key to identification is provided. (Received 4 May 1992; accepted 4 January 1993)  相似文献   
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The heat‐ and odour‐producing genus Arum (Araceae) has interested scientists for centuries. This long‐term interest has allowed a deep knowledge of some complex processes, such as the physiology and dynamics of its characteristic lure‐and‐trap pollination system, to be built up. However, mainly because of its large distributional range and high degree of morphological variation, species' limits and relationships are still under discussion. Today, the genus comprises 28 species subdivided into two subgenera, two sections and six subsections. In this study, the phylogeny of the genus is inferred on the basis of four plastid regions, and the evolution of several morphological characters is investigated. Our phylogenetic hypothesis is not in agreement with the current infrageneric classification of the genus and challenges the monophyly of several species. This demonstrates the need for a new infrageneric classification based on characters reflecting the evolution of this enigmatic genus. To investigate the biogeography of Arum deeply, further spatiotemporal analyses were performed, addressing the importance of the Mediterranean basin in the diversification of Arum. Our results suggest that its centre of origin was the European–Aegean region, and that major diversification happened during the last 10 Myr. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163 , 14–32.  相似文献   
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