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31.
As a result of parasitism by Glyptapanteles liparidis in the first, second, third and fourth instar larvae of Acronicta rumicis, the mortality of each larval stage was found to be 46.67, 90, 71 and 16.67%, respectively. The mortality was highest when G. liparidis parasitized the second and third instar larvae. The difference in mortality between the parasitized group and the control group was 72.14% in the second instar larvae. With regards to the food consumption of the parasitized larvae, the first and second instar larvae consumed 6495.58 ± 646.52 mm2 (leaf surface) and 7951.12 ± 4167.36 mm2, respectively, while the third and fourth larvae consumed 13 826.77 ± 3396.66 mm2 and 18 599.85 mm2, respectively, showing that food consumption increased with instar stages of the host larvae. The clutch size of G. liparidis increased in relation to the instar stages of the host: it was 25.25 ± 7.89, 48.65 ± 53.75, 91.09 ± 44.52 and 114 individuals when they were fed with the first, second, third and the fourth instar larvae of the host, respectively.  相似文献   
32.
Polyclonal antibodies made against 86 kDa (86 k), 80 kDa (80 k) and 54 kDa (54 k) vitellins of Oxya japonica japonica are used for Western blotting. Anti‐80k vitellin antibody is cross‐reacted with a 95 kDa (95 k) vitellin. While 95 k vitellin is present both in the female hemolymph and in the oocyte, 80 k vitellin is detected only in the oocyte and the laid egg. In the growing oocytes, as 95 k vitellin is faded out gradually, 80 k vitellin is accumulated increasingly, indicating postendocytic processing of 95 k vitellin brings 80 k vitellin. Further conforming the hypothesis, partial digestion of 95 k vitellin with pepsin and α‐chymotrypsin makes several protein bands of molecular weight around 80 kDa. Thus, the 95k vitellin may have a cleavage site (s) to produce 80 k vitellin which forms fairly stable tertiary structure. In the reduced condition (20 mM glutathion), both 95 k and 80 k vitellins were digested throughly by endogenous proteinase at pH 4. Both 86 k and 54 k vitellins, respectively, show no apparent molecular weight changes in the growing oocyte and in the hemolymph.  相似文献   
33.
The genus Hexabathynella (Crustacea, Malacostraca, Bathynellacea) is revised in the sense of the phylogenetic systematics and four new species are described from South Africa ( H. monoaethetasca sp. nov. and H. africana sp. nov. ) and America ( H. schrieveri sp. nov. and H. virginiae sp. nov. ). A comparative analysis of all observable outer structures distributed in 18 known and four new species resulted in a re-evaluation of 18 characters and character states. The phylogenetic analysis using the program PAUP yielded one most-parsimonious tree, which suggests the grouping of ( H. decora (( H. halophila  +  H. aotearoae ) + ( H. pauliani ( H. monoaethetasca  + H. africana )))) + ( H. knoepffleri ( H. nicoleiana ( H. hebrica , H. tenera , H. longiappendiculata , H. breviappendiculata , H. nestica ) +  H. virginiae (( H. minuta ( H. valdecasasi + H. otayana )) + ( H. hessleri + H. muliebris ))) +  H. paranaensis ( H. szidati + H. schrieveri )). The tree is 57 steps long and has a consistency index of 0.6140, a retention index of 0.7982 and a rescaled consistency index of 0.4901. The result does not agree with the previous analyses on the genus. In terms of sampling and coding, the characters used in the previous study are critically assessed.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 71–96.  相似文献   
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WE reported accelerated transformation by DNA viruses (SV40 and polyoma) in rat embryo (RE) cells chronically infected with a C-type RNA virus1,2. Recently we found in RE cells transformed by polyoma virus a new complement-fixing (CF) antigen detectable by rat antisera having broad reactivity with the various intraspecies and interspecies antigens of the RNA tumour viruses3–8; this antigen, however, was distinct from the murine intraspecies and interspecies group-specific (gs) antigens both immunologically and by virtue of other properties. It is also distinct from the polyoma virion (capsid) and tumour (“T”) antigens.  相似文献   
37.

Background

Tortricidae, one of the largest families of microlepidopterans, comprise about 10,000 described species worldwide, including important pests, biological control agents and experimental models. Understanding of tortricid phylogeny, the basis for a predictive classification, is currently provisional. We present the first detailed molecular estimate of relationships across the tribes and subfamilies of Tortricidae, assess its concordance with previous morphological evidence, and re-examine postulated evolutionary trends in host plant use and biogeography.

Methodology/Principal Findings

We sequenced up to five nuclear genes (6,633 bp) in each of 52 tortricids spanning all three subfamilies and 19 of the 22 tribes, plus up to 14 additional genes, for a total of 14,826 bp, in 29 of those taxa plus all 14 outgroup taxa. Maximum likelihood analyses yield trees that, within Tortricidae, differ little among data sets and character treatments and are nearly always strongly supported at all levels of divergence. Support for several nodes was greatly increased by the additional 14 genes sequenced in just 29 of 52 tortricids, with no evidence of phylogenetic artifacts from deliberately incomplete gene sampling. There is strong support for the monophyly of Tortricinae and of Olethreutinae, and for grouping of these to the exclusion of Chlidanotinae. Relationships among tribes are robustly resolved in Tortricinae and mostly so in Olethreutinae. Feeding habit (internal versus external) is strongly conserved on the phylogeny. Within Tortricinae, a clade characterized by eggs being deposited in large clusters, in contrast to singly or in small batches, has markedly elevated incidence of polyphagous species. The five earliest-branching tortricid lineages are all species-poor tribes with mainly southern/tropical distributions, consistent with a hypothesized Gondwanan origin for the family.

Conclusions/Significance

We present the first robustly supported phylogeny for Tortricidae, and a revised classification in which all of the sampled tribes are now monophyletic.  相似文献   
38.
This paper addresses the question of whether one can economically improve the robustness of a molecular phylogeny estimate by increasing gene sampling in only a subset of taxa, without having the analysis invalidated by artifacts arising from large blocks of missing data. Our case study stems from an ongoing effort to resolve poorly understood deeper relationships in the large clade Ditrysia ( > 150,000 species) of the insect order Lepidoptera (butterflies and moths). Seeking to remedy the overall weak support for deeper divergences in an initial study based on five nuclear genes (6.6 kb) in 123 exemplars, we nearly tripled the total gene sample (to 26 genes, 18.4 kb) but only in a third (41) of the taxa. The resulting partially augmented data matrix (45% intentionally missing data) consistently increased bootstrap support for groupings previously identified in the five-gene (nearly) complete matrix, while introducing no contradictory groupings of the kind that missing data have been predicted to produce. Our results add to growing evidence that data sets differing substantially in gene and taxon sampling can often be safely and profitably combined. The strongest overall support for nodes above the family level came from including all nucleotide changes, while partitioning sites into sets undergoing mostly nonsynonymous versus mostly synonymous change. In contrast, support for the deepest node for which any persuasive molecular evidence has yet emerged (78-85% bootstrap) was weak or nonexistent unless synonymous change was entirely excluded, a result plausibly attributed to compositional heterogeneity. This node (Gelechioidea + Apoditrysia), tentatively proposed by previous authors on the basis of four morphological synapomorphies, is the first major subset of ditrysian superfamilies to receive strong statistical support in any phylogenetic study. A "more-genes-only" data set (41 taxa×26 genes) also gave strong signal for a second deep grouping (Macrolepidoptera) that was obscured, but not strongly contradicted, in more taxon-rich analyses.  相似文献   
39.
中国蓝带蚊的系统发育数值分析   总被引:5,自引:0,他引:5  
本文应用系统发育数值分析方法,对我国已知22种蓝带蚊的幼虫、雌蚊和雄蚊69个综合特征进行数值分析.根据修正的Wagner法计算值画出的分支图,与聚类分析法画出的矩阵图作比较,认为分支图更能反映已知种间的亲缘关系,并结合蓝带蚊属全球已知种的区系分布,计算各区的祖系比值作分析,新热带区的祖系比值特大,可能是蓝带蚊属的发源地.  相似文献   
40.
Summary

Previous studies have shown that spatiotemporal regulation of extracellular matrix (ECM) by proteinases is implicated in the initial step of regeneration. In amphibian regeneration, the up-regulation of proteinases such as metalloproteinases (MMPs) and cathepsin D, and proteinase-related proteins such as proteinase tissue inhibitors and activators has been demonstrated. Since the earthworm could provide a unique and valuable model to investigate the mechanism of regeneration, we studied the developmental change in proteinase expression during earthworm tail regeneration. Zymographic analysis revealed that proteinase activities began to increase within 1 h after amputation and reached a maximum at 7 days post-amputation. This peak in activity was approximately 22-fold greater than the unamputated controls. Thereafter, the proteinase activities tended to decrease followed by another peak at 30 days before returning to control levels. At least four types of proteinase were distinguishable at 7 and 30 days post-amputation, with molecular weights of 25, 28, 38, and 44 kDa, respectively. All proteinase activities were strongly inhibited by addition of phenylmethylsulfonyl fluoride (PMSF) and aprotinin, specific inhibitors for serine proteinase. Pepstatin A, E-64, iodoacetamide and a metal ion-free medium were not effective inhibitors, indicating that proteinases expressed during earthworm tail regeneration would be serine proteinases. In addition, we were able to detect two types of plasminogen activator (PA) with molecular weights of 40 and 47 kDa, respectively. PA activities were predominantly expressed at 1, 5, and 25 days post-amputation, which preceded two peaks of serine proteinase activities appearing at approximately 7 and 30 days after amputation, respectively. This fact supports the view that serine proteinases expressed in respond to tail amputation may be plasmin-like proteinases activated by PA.  相似文献   
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