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911.
ROGER DE CANDOLLE ALAN RADCLIFFE-SMITH 《Botanical journal of the Linnean Society. Linnean Society of London》1981,83(4):325-348
The botanical career of Nathaniel Wallich is followed; his collecting activities in Asia enumerated, and the final disposition of his huge herbarium, largely the property of the Honourable East India Company, is given. His relationship with numerous eminent contemporary botanists, and particularly with the de Candolles of Geneva, is described, together with the role that each played in assisting Wallich to work up his material.
A full list of the works used in the composition of this paper is given in an Appendix rather than following the usual citation convention. Copies of the correspondence between Wallich and the de Candolles of Geneva are available on microfiche. 相似文献
A full list of the works used in the composition of this paper is given in an Appendix rather than following the usual citation convention. Copies of the correspondence between Wallich and the de Candolles of Geneva are available on microfiche. 相似文献
912.
Nine-day chicken embryo neuroretinal cells transdifferentiate into both lens and pigment cells after 3–4 weeks when cultured in MEM medium containing 10% foetal calf serum at pH 7.4. At pH 6.8. the appearance of lens crystallins is retarded and cholineacetyltransferase (CAT) activity persists for longer, whereas at pH 8.0 crystallins appear earlier and CAT activity declines more rapidly. Cell survival and culture growth are about 10% lower at pH 6.8 than at pH 8.0. If the concentration of foetal calf serum (FCS) is increased from 10% to 25% (at pH 7.4), cell survival and growth are both promoted, crystallins appear slightly earlier and CAT activity declines more rapidly. Converse effects are observed with 5 % serum, accumulation of crystallins being greatly inhibited and CAT activity prolonged. Crystallin production in cultures with 10% or 25% chicken serum (CS) is much less extensive than in similar FCS cultures, but in cultures with 5 % CS, crystallins appear more rapidly, reaching higher levels than in 5 % FCS cultures. However, the pattern of CAT activity in response to different serum levels is similar for both CS and FCS. This might imply the presence of some factor(s) able to stimulate transdifferentiation in FCS, whereas CS can apparently inhibit this process. 相似文献
913.
ZOLTÁN BOCHDANOVITS GERDIEN DE JONG 《Biological journal of the Linnean Society. Linnean Society of London》2003,80(4):717-725
Contrary to the conventional wisdom 'bigger is better', evolution at high temperature invariably leads to small individuals in Drosophila melanogaster . Natural selection is known to be responsible, meaning that genotypes that are small because of adaptation to high temperature must have some temperature dependent fitness advantage. In this study we consider both preadult and adult fitness components, and show that large adults from a cold adapted population significantly outperform small adults from a warm adapted population only when tested at low temperature and low larval density. In all other conditions 'bigger is not necessarily better', meaning that environmental influences are capable of altering the association between size and fitness. Yet, 'smaller wasn't better either' under any condition, when considering the overall measure of fitness. Examination of individual fitness components revealed population by temperature interaction in preadult survival; this interaction is potentially capable of explaining the temperature specific advantage of small adult body size. At high temperature, the warm adapted population exhibits superior preadult survival while producing small adults. Geographical variation in adult body size seems to be the result of selection on larval growth and competitive strategies, resulting in alterations in the association between fitness components. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 80 , 717–725. 相似文献
914.
A new species of Exostyles (Leguminosae, Papilionoideae, Swartzieae s.l.), from Paraná State, Brazil
LUCIA HELENA SOARES-SILVA VIDAL DE FREITAS MANSANO 《Botanical journal of the Linnean Society. Linnean Society of London》2004,146(1):103-106
A new species Exostyles godoyensis Soares-Silva & Mansano (Leguminosae, Papilionoideae, Swartzieae), endemic to Paraná state in southern Brazil, is described and illustrated. The new species is distinct from all the other species of Exostyles in having a leaf with up to five leaflets, while the other species have at least seven leaflets per leaf. The new species is distinct from Exostyles amazonica Yakovlev in its longer stamen filaments and ovary stipe and from E. glabra Vogel and E. venusta Schott by its shorter anthers. In addition to these morphological characters E. godoyensis has a disjunct geographical distribution. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 103–106. 相似文献
915.
CONSUELO DÍAZ DE LA GUARDIA GABRIEL BLANCA 《Botanical journal of the Linnean Society. Linnean Society of London》2004,146(4):505-511
Tragopogon cazorlanum (Asteraceae: Lactuceae) is proposed as a new Spanish species with distribution restricted to the Baetic mountains (south-eastern Spain). Its morphological, palynological, chromosomal, biogeographical and ecological features are discussed, as well as its main relationships and differences with reference to other Spanish species of the genus. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 505–511. 相似文献
916.
A review of the genus Semele (Ruscaceae) systematics in Madeira 总被引:2,自引:0,他引:2
MIGUEL ÂNGELO ALMEIDA PINHEIRO DE CARVALHO CHRISTOPHER CHARLES WILCOCK TERESA MARIA MARQUES DOS SANTOS IOLANDA CATARINA VALE LUCAS JOSÉ FILIPE TEIXEIRA GANANÇA EMANUEL FRANCO DEVARAJAN THANGADURAI DOULATHABAD MURALIDHARA RAO NÉLIA FREITAS SOUSA 《Botanical journal of the Linnean Society. Linnean Society of London》2004,146(4):483-497
The present study attempts to review the systematics of Semele (Ruscaceae) in Madeira, based on phenotypic diversity. The variation in some vegetative (climbing shoot, second-order branches or 'phylloclades') and sexual (inflorescence and flowers) characters was analysed in 115 plant specimens from 30 field populations, herbaria of the Costa collection and Madeira Botanical Garden (MADJ) and certain gardens. Thirty-one quantitative and qualitative characters have been utilized in the analysis. Kaiser–Meyer–Olkin (KMO) analysis indicates adequate sampling. Principal component analysis (PCA) reveals that the spatial distribution of individuals has a discontinuous behaviour. Principal coordinate analysis (PCO) utilizing the Gower coefficient on standardized data revealed a significantly discontinuous distribution of individuals, such that two different clusters can be defined. The Student's t -test and Tukey test on separate characters, when individuals were classified according to the Costa classification, confirms the significant differences between grouping accessions. This leads to the recognition of two species within the genus in Madeira. Literature and herbarium studies show that these two taxa are conspecific with Semele androgyna (L.) Kunth sensu stricto (s.s.) and Semele menezesi Costa sensu lato (s.l.) . A separated statistical analysis of the S. androgyna cluster shows the possible existence of additional subgroups. Based on field population distribution, ecological behaviour and variation in features, we propose the recognition of two species, S. androgyna (L.) Kunth and S. menezesi (Costa) Pinheiro de Carvalho, and two subspecies S. androgyna (L.) Kunth androgyna Pinheiro de Carvalho and S. androgyna (L.) Kunth pterygophora Pinheiro de Carvalho. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 483–497. 相似文献
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