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Thirty populations of potato cyst nematode (Globodera spp.) from the Island of Tenerife and two populations from the UK were assessed for several morphometric and non-morphometric characters thought to discriminate between the species G. rostochiensis and G. pallida. Also 200 cysts from each population were analysed by isoelectric focusing of soluble proteins. Correlation analysis, analysis of variance and principal component analysis were used to investigate relationships between the morphometric characters, how the relationships varied between species and between populations, and which characters were most useful for discriminating between species. The two species differed significantly for each of the four morphometric characters: stylet length, fenestra length, anus-fenestra distance and the number of ridges. The stylet length and fenestra length also showed differences between populations of G. rostochiensis while stylet length and number of ridges showed differences between populations of C. pallida. In general, populations of G. pallida showed greater variation than populations of C. rostochiensis. Principal component analysis of the population means indicated that over 73% of the variation in the characters could be explained by the contrast of stylet and fenestra lengths against the anus-fenestra distance and number of ridges. A plot of the first two principal components separated the two species. Stepwise discriminant analysis provided a linear combination of these four variables which discriminated between the species. Stylet length was found to be the most useful characteristic for distinguishing the species whilst anus-fenestra distance was the least useful. 相似文献
63.
STELLA M. GONZALEZ CAPPA ADRIANA BRONZINA ALEJANDRO M. KATZIN HUMBERTO GOLFERA GLADYS W. DE MARTINI ELSA L. SEGURA 《The Journal of eukaryotic microbiology》1980,27(4):467-471
SYNOPSIS. The relation of humoral antibody response to protection was evaluated in mice immunized with whole homogenates of Trypanosoma cruzi or with its flagellar fraction by direct agglutination and indirect fluorescent antibody test as well as by lytic and neutralizing activity against blood trypomastigotes. The results indicated that lytic antibodies were not implicated directly in protection against these trypanosomes. It was evident from histopathologic examination that the higher the degree of protection achieved, the lower the tissue damage observed in the challenged mice. Serum-neutralizing activity was highest in the groups protected most effectively. 相似文献
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The sardine Sardina pilchardus Walbaum, 1792 is a small pelagic fish species that sustains an economically important fishery in the eastern Atlantic Ocean. Eight perfect microsatellite loci of sardine were characterized from a partial genomic library enriched for CA repeat sequences. All loci revealed high levels of polymorphism, with the number of alleles per locus ranging between 22 and 45, and an average observed heterozygosity of 0.772. The newly described loci can be employed to determine population genetic structure of the sardine, and may aid in fishery management of this species. 相似文献
66.
VICTOR H. GONZALEZ TERRY GRISWOLD CHRISTOPHE J. PRAZ BRYAN N. DANFORTH 《Systematic Entomology》2012,37(2):261-286
Phylogenetic relationships within the bee family Megachilidae are poorly understood. The monophyly of the subfamily Fideliinae is questionable, the relationships among the tribes and subtribes in the subfamily Megachilinae are unknown, and some extant genera cannot be placed with certainty at the tribal level. Using a cladistic analysis of adult external morphological characters, we explore the relationships of the eight tribes and two subtribes currently recognised in Megachilidae. Our dataset included 80% of the extant generic‐level diversity, representatives of all fossil taxa, and was analysed using parsimony. We employed 200 characters and selected 7 outgroups and 72 ingroup species of 60 genera, plus 7 species of 4 extinct genera from Baltic amber. Our analysis shows that Fideliinae and the tribes Anthidiini and Osmiini of Megachilinae are paraphyletic; it supports the monophyly of Megachilinae, including the extinct taxa, and the sister group relationship of Lithurgini to the remaining megachilines. The Sub‐Saharan genus Aspidosmia, a rare group with a mixture of osmiine and anthidiine features, is herein removed from Anthidiini and placed in its own tribe, Aspidosmiini, new tribe . Protolithurgini is the sister of Lithurgini, both placed herein in the subfamily Lithurginae; the other extinct taxa, Glyptapina and Ctenoplectrellina, are more basally related among Megachilinae than Osmiini, near Aspidosmia, and are herein treated at the tribal level. Noteriades, a genus presently in the Osmiini, is herein transferred to the Megachilini. Thus, we recognise four subfamilies (Fideliinae, Pararhophitinae, Lithurginae and Megachilinae) and nine tribes in Megachilidae. We briefly discuss the evolutionary history and biogeography of the family, present alternative classifications, and provide a revised key to the extant tribes of Megachilinae. 相似文献
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Summary. The genetic distances separating 14 Spanish goat breeds are calculated from gene frequency data of 14 genetic blood markers (GSH, Ke, Hb, Dia, Ct, MDH, CA, X, NP, Alp, Am, Cp, Tf and Al).
Working from the matrix of Nei's genetic distances we drew a dendrogram demonstrating a great genetic similarity among populations from Negra Serrana, Zamorana, Guadarrama, Retinta, Blanca Andaluza, Berciana and Pirenaica on one hand; and Canaria, Murciana, Blanca Celtibérica, Verata, Palmera, Malaguena and Granadina on the other.
We discuss the similarities and differences within our classification using gene frequency data of the blood genetic markers studied, and classifications based chiefly on morphological and production data. 相似文献
Working from the matrix of Nei's genetic distances we drew a dendrogram demonstrating a great genetic similarity among populations from Negra Serrana, Zamorana, Guadarrama, Retinta, Blanca Andaluza, Berciana and Pirenaica on one hand; and Canaria, Murciana, Blanca Celtibérica, Verata, Palmera, Malaguena and Granadina on the other.
We discuss the similarities and differences within our classification using gene frequency data of the blood genetic markers studied, and classifications based chiefly on morphological and production data. 相似文献
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70.