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31.
Although the papilionid butterfly Luehdorfia japonica, usually lays eggs on new leaves of the host plant (Asarum sp.; Aristolochiaceae), eggs of the butterfly were frequently found on old leaves of Asarum megacalyx in Suyama, Tokamachi, Niigata prefecture. Larvae hatched on new leaves and those hatched on old leaves did not show significant differences in their survival rate in the field. In laboratory breeding, about 90% of larvae that were fed old leaves survived and developed normally to the pupal stage. Their growth rate, however, was slightly lower than those that were fed new leaves. No nutritional differences were found between the old and new leaves. The reason why oviposition on the old leaves was so frequent and why larvae that hatched on old leaves could survive in the study area is discussed.  相似文献   
32.
We reared wild type (Canton-S) and period mutant flies, i.e., per(S) and per(L), of Drosophila melanogaster in constant darkness, constant light or 24h light dark cycles with various light to dark ratios throughout the development from embryo to early adult. The locomotor activity rhythms of newly eclosed individuals were subsequently monitored in the lighting conditions, in which they had been reared, for several days and then in constant darkness. Circadian rhythms were clearly exhibited in constant darkness even in flies reared in constant light and constant darkness as well as flies reared in light-dark cycles, but the freerunning period differed among groups. The results suggest that the circadian clock is assembled without any cyclical photic information, and that the light influences the developing circadian clock of Drosophila to alter the freerunning period. The effects of light on the rhythm differed in some aspects between per(L) flies and the other two strains. Possible mechanisms through which light affects the developing circadian clock are discussed. Copyright 1997 Elsevier Science Ltd. All rights reserved  相似文献   
33.
A rapid colorimetric method has been described for the quantitative determination of mimosine by using activated carbon as a decolorizing agent and measuring the intensity of mimosine-ferric chloride color produced.  相似文献   
34.
Transgenic fish carrying a reconstructed mouse tyrosinase gene, mg-Tyrs-J, were produced by microinjecting the gene into the oocyte nucleus of an orange-colored variant of medaka (Oryzias latipes). Of 64 oocytes microinjected and subsequently inseminated, 13 embryos developed normally beyond hatching and three of them exhibited brown skin pigmentation in the adult as was commonly observed in the wild type of this species. Light and electron microscopic examination disclosed a ubiquitous distribution of typical melanophores in the skin of these transgenic fish. Judging from their population density and distribution pattern, it was presumed that melanogenesis in these fish was elicited in amelanotic melanophores that resided in the skin of the orange-colored fish of this variant. Immunofluorescence with use of the anti-mouse tyrosinase antiserum lacking reactivity to medaka tyrosinase clearly disclosed that the gene introduced was expressed in the melanophores of transgenic fish. Crosses of female transgenic fish and males from an orange-colored variant yielded offspring exhibiting wild-type or orange-colored pigmentation in a ratio of 1:1, thus implying that mg-Tyrs-J integrated into the medaka genome behaves like a dominant gene. Little melanogenesis was observed in xanthophores, leucophores and iridophores in transgenic fish, suggesting possible specificity in recognition of teleostean cell types (i.e., melanophores) by the regulatory region of the mouse tyrosinase gene.  相似文献   
35.
When koa haole leaves were stored at elevated temperatures the mimosine content was decreased. The effect was most pronounced and rapid when the temperature was over 70 °C. in the presence of moisture. A similar effect occurred in seeds when sufficient moisture was present. The phenomenon did not take place in dry leaves. Steam was effective in extracting mimosine from koa haole leaves.Heated koa haole leaf meal has been demonstrated to be less toxic than unheated koa haole leaf meal when the meals are fed to albino rats as part of their rations. The development of alopecia in rats fed unheated koa haole meal has been described, and the growth curves of rats fed heated and unheated leaf meals and basal rations have been compared.Ferrous sulfate added to rations containing unheated koa haole leaf meal has been shown to be effective in reducing mimosine toxicity.  相似文献   
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Oviposition behavior of Zatypota albicoxa (Walker) is described. This wasp parasitizes the house spider Achaearanea tepidariorum (Koch), which weaves irregular, three-dimensional webs. Based on field observations, two modes of oviposition behavior were recognized. In one, the wasp hung on the web, pulling the thread with its fore leg, until the spider lifted it up (ambush-style). In the other mode, the wasp climbed the web (climbing-style). Under laboratory conditions in an aquarium, the wasp hung on the web in mid height of the gumfoot thread as in the former style, then flew toward unaware spider and paralyzed it. After paralyzing, the wasp usually rubbed the spider's abdomen with its ovipositor and tip of metasoma repeatedly at short intervals for several minutes. In all cases they adopted the same posture in which they grasped the spider abdomen with fore and mid legs during oviposition. As female wasps emerged from larger hosts and male wasps emerged from smaller ones, the ovipositing wasp apparently assesses the size of the spider and chooses whether to lay a fertilized or an unfertilized egg. In addition, it was confirmed that Z. albicoxa expelled the eggs not from the tip of the ovipositor but from the tip of its abdomen, as in other species of the Polysphincta group (e.g. Hymenoepimecis argyraphaga , Reclinervellus tuberculatus and Schizopyga circulator ).  相似文献   
39.
The phylogenetic relationships between genera of the Polysphincta group of Pimplinae (Ichneumonidae) were surveyed using molecular markers, partial sequences of cytochrome c oxidase I (COI), 28S rRNA and elongation factor 1α, and maximum likelihood and Bayesian approaches to obtain a robust phylogenetic hypothesis to understand the evolution of the group. The Polysphincta group was recovered as monophyletic, although relationships between genera were different from previous hypotheses based on morphological data. Within the Polysphincta group, three major clades were recognized and phylogenetic relationships among them were well resolved as (Schizopyga subgroup + (Acrodactyla subgroup + Polysphincta subgroup)). The Schizopyga subgroup consisted of the genera Piogaster, Schizopyga, Zabrachypus and Brachyzapus. As the genus Schizopyga was found to be polyphyletic, the genus Dreisbachia, which had been synonymized under Schizopyga, was resurrected and Iania gen.n. is proposed for Dreisbachia pictifrons, to maintain monophyletic genera. Species of the Schizopyga subgroup utilize spiders constructing egg‐laying chambers or funnel webs as hosts. The genus Piogaster was not recovered as the sister to all other members of the genus group, unlike previous hypotheses, but was nested in this clade as (Zabrachypus + ((Brachyzapus + Schizopyga) + (Dreisbachia + (Iania + Piogaster)))). Members of the Acrodactyla and Polysphincta subgroups attack spiders that weave aerial webs. The host range of the former is centred on tetragnathid and linyphiid spiders, the host range of the latter seems to centre mainly on orb‐weaving araneids and partly on theridiids weaving three‐dimensional (3D) irregular webs. Based on the obtained phylogeny of the group, the evolution of larval and cocoon morphology, and the mode of parasitism are discussed. Acrodactyla varicarinata Uchida & Momoi and A. inoperta Kusigemati are transferred to the genus Megaetaira ( comb.n.). This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:0AB1086F‐9F23‐4057‐B7ED‐3A3943E19C61 .  相似文献   
40.
Gonatopus javanus (R.C.L. Perkins) was newly recorded from Japan and India. The males collected together with females of G. javanus from Japan were identified as previously unknown opposite sex of the species because they share identical sequences of mitochondrial COI. The sequence was different from that of G. clavipes (Thunberg) by 11%. The male of G. javanus was described as new to science. Doratulina producta (Matsumura) is implied as host in Japan. The utility of molecular marker to identify the dryinid taxa showing sexual dimorphism is discussed.  相似文献   
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