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41.
TIM H. SPARKS ALEKSANDRA LANGOWSKA ADAM GŁAZACZOW ZDZISŁAW WILKANIEC MAŁGORZATA BIEŃKOWSKA PIOTR TRYJANOWSKI 《Ecological Entomology》2010,35(6):788-791
1. The honeybee Apis mellifera is of huge worldwide economic importance in the pollination of crops for human consumption. In recent years, honeybee populations have declined under pressure from diseases and pests. Climate change is increasingly being viewed as an additional threat to honeybees and yet only limited research has been carried out in this area. 2. This paper reports the advance of the first cleansing flight (‘spring cleaning’) of the honeybee in Poznań, Poland, i.e. flights to excrete faeces, over a month in the period 1985–2009. The timing of this flight is advanced not only by higher late winter/spring temperatures but also by higher temperatures in the previous summer and autumn. 3. This earlier activity gives hope that the reported earlier flowering of many native and cultivated species will not cause a pollination synchrony crisis. 相似文献
42.
We looked for evidence of a cost of reproduction in the Marsh Tit Parus palustris living in the last fragments of primeval temperate forest (Białowieża National Park, eastern Poland). Potential nest-holes were superabundant but the birds had to cope with a diverse set of predators, dangerous both to broods and to parents. Taking advantage of the natural variation in realized reproductive investment that this caused in terms of the loss of nests or mates, we expected to find differences in survival and future fecundity between birds which had lost broods (reduced effort), had reared young (controls) or were either provisioning young single-handed or had laid replacement clutches (increased effort). Despite 13 years of observation, even during seasons with very strenuous conditions, we have failed to demonstrate that the observed range of variation in parental investment caused any demographic cost of reproduction. Incubating females were regularly killed on the nest, which could indicate the existence of a cost operating in the earlier stages of the breeding cycle. Overall, these results suggest that the reproductive rate in Marsh Tits is not controlled proximately by reproductive cost. 相似文献
43.
Paweł JAŁOSZYŃSKI 《Entomological Science》2012,15(1):35-41
Scydmaenine beetles are commonly described as predators specialized in capturing and feeding on armored mites of the order Oribatida, and documented cases of feeding on other live arthropods have not been known. Based on laboratory observations and a broad choice of Acari (armored and soft‐bodied) and other soil arthropods, food preferences and associated behavior of two scydmaenine species are clarified and described. Adults of Scydmaenus tarsatus ignored oribatid and mesostigmatan mites, but readily attacked and fed on a soft‐bodied Rhizoglyphus sp. (Acaridae), and on small springtails, especially on Ceratophysella denticulata (Hypogastruridae). A water drinking behavior was observed for this species, not reported previously in any Staphylinidae. Scydmaenus hellwigii ignored all tested Acari (including Rhizoglyphus) and scavenged on dead neanurine collembolans or freshly cut pieces of large springtails; a long term culture was maintained by feeding beetles with isotomid springtails. Previously reported strict specialization of Scydmaenus as a predator on Oribatida was not confirmed and it is concluded that the studied species feed on live soft‐bodied organisms and scavenge on dead arthropods. 相似文献
44.
ANDRZEJ ELZANOWSKI MAŁGORZATA BIEŃKOWSKA‐WASILUK RAFAL CHODYŃ WIESŁAW BOGDANOWICZ 《Palaeontology》2012,55(6):1199-1221
Abstract: Two European species of the Diomedeoididae, an extinct family of procellariiform (tube‐nose) birds, have hitherto been distinguished primarily by size of their limb bones. Here, we describe an Early Oligocene (Rupelian) procellariifom coracoid that in all probability represents the larger species, Diomedeoides lipsiensis, and compare it to the coracoids of smaller diomedeoidids and extant procellariiforms. Using multivariate (Principal Component Analysis) and univariate analyses, we demonstrate that nearly all measurements are heavily size dependent, which makes the proportions and some other shape characters of little use as phylogenetic markers. Among eight measurements, the coracoid corpus width shows the highest correlation (higher than corpus depth) with body mass, permitting a precise calculation of over twofold difference in body mass between D. lipsiensis and smaller species. Among 16 qualitative characters analysed, the majority proved too variable to be used as markers of interfamily relationships and only 2–3, the ventral intermuscular line, sternocoracoid articulation (divided vs. undivided), and, with reservations, epimarginal crest vary consistently between the families. By far the most variable is the acrocoracoid process that tends to be deeper (more elongate dorsoventrally) in larger petrels but not in the albatrosses. However, the detailed shapes of the acrocoracoid heads are highly genus specific and suggest a genus‐level diversity among the Diomedeoididae from the Oligocene of Europe. The common features of the diomedeoidid coracoids are best interpreted as plesiomorphies, which accounts for some similarities to the Oceanitinae (that are probably basal among the crown‐group procellariiforms). The evidence from the coracoid is consistent with a stem‐group position of the Diomedeoididae as previously proposed by others. We emphasize the need of a group‐specific character analysis, primarily of allometries and levels of character variation, prior to a phylogenetic reconstruction. 相似文献
45.
Phylogeny and classification of Cucujoidea and the recognition of a new superfamily Coccinelloidea (Coleoptera: Cucujiformia) 下载免费PDF全文
JAMES A. ROBERTSON ADAM ŚLIPIŃSKI MATTHEW MOULTON FLOYD W. SHOCKLEY ADRIANO GIORGI NATHAN P. LORD DUANE D. MCKENNA WIOLETTA TOMASZEWSKA JUANITA FORRESTER KELLY B. MILLER MICHAEL F. WHITING JOSEPH V. MCHUGH 《Systematic Entomology》2015,40(4):745-778
A large‐scale phylogenetic study is presented for Cucujoidea (Coleoptera), a diverse superfamily of beetles that historically has been taxonomically difficult. This study is the most comprehensive analysis of cucujoid taxa to date, with DNA sequence data sampled from eight genes (four nuclear, four mitochondrial) for 384 coleopteran taxa, including exemplars of 35 (of 37) families and 289 genera of Cucujoidea. Maximum‐likelihood analyses of these data present many significant relationships, some proposed previously and some novel. Tenebrionoidea and Lymexyloidea are recovered together and Cleroidea forms the sister group to this clade. Chrysomeloidea and Curculionoidea are recovered as sister taxa and this clade (Phytophaga) forms the sister group to the core Cucujoidea (Cucujoidea s.n .). The nitidulid series is recovered as the earliest‐diverging core cucujoid lineage, although the earliest divergences among core Cucujoidea are only weakly supported. The cerylonid series (CS) is recovered as monophyletic and is supported as a major Cucujiform clade, sister group to the remaining superfamilies of Cucujiformia. Currently recognized taxa that were not recovered as monophyletic include Cucujoidea, Endomychidae, Cerylonidae and Bothrideridae. Biphyllidae and Byturidae were recovered in Cleroidea. The remaining Cucujoidea were recovered in two disparate major clades: one comprising the nitidulid series + erotylid series + Boganiidae and Hobartiidae + cucujid series, and the other comprising the cerylonid series. Propalticidae are recovered within Laemophloeidae. The cerylonid series includes two major clades, the bothriderid group and the coccinellid group. Akalyptoischiidae are recovered as a separate clade from Latridiidae. Eupsilobiinae are recovered as the sister taxon to Coccinellidae. In light of these findings, many formal changes to cucujiform beetle classification are proposed. Biphyllidae and Byturidae are transferred to Cleroidea. The cerylonid series is formally recognized as a new superfamily, Coccinelloidea stat.n. Current subfamilies elevated (or re‐elevated) to family status include: Murmidiidae stat.n. , Teredidae stat.n. , Euxestidae stat.n. , Anamorphidae stat.rev. , Eupsilobiidae stat.n. , and Mycetaeidae stat.n. The following taxa are redefined and characterized: Cleroidea s.n. , Cucujoidea s.n. , Cerylonidae s.n. , Bothrideridae s.n. , Endomychidae s.n. A new subfamily, Cyclotominae stat.n. , is described. Stenotarsinae syn.n. is formally subsumed within a new concept of Endomychinae s.n. 相似文献
46.
JAMES A. ROBERTSON ADAM ŚLIPIŃSKI KEVIN HIATT KELLY B. MILLER MICHAEL F. WHITING JOSEPH V. MCHUGH 《Systematic Entomology》2013,38(1):209-232
Eight genes (nuclear: 18S, 28S, H3, CAD; mitochondrial: 12S, 16S, COI, COII) and morphology were used to infer the evolutionary history of Corylophidae, some of the smallest free‐living insects. The study included 36 corylophid exemplars, representing approximately 60% of the known generic diversity of the family and 16 cucujoid outgroup taxa. Multiple partitioning strategies, molecular datasets, combined datasets and different taxon sampling regimes using maximum likelihood and mixed‐model Bayesian inference were utilized to analyse these data. Most results were highly concordant across analyses. There was strong agreement across (i) partitioning strategies, (ii) maximum likelihood and Bayesian inference analyses of the molecular data, and (iii) Bayesian inference of the molecular data alone and Bayesian inference of the combined morphological and molecular data when all terminal taxa were included. When a strict taxon sampling protocol was employed so that only single generic exemplars were included, deep relationships were affected in the resulting phylogenetic hypotheses. Under such narrow sampling strategies, deep phylogenetic relationships were also sensitive to the choice of generic exemplars. Although it is often challenging to obtain single representatives for many taxa in higher‐level phylogenetic analyses, these results indicate the importance of using denser taxon sampling approaches even at the specific level for genera included in such studies. Molecular data alone support Anamorphinae (Endomychidae) strongly as the sister group of Corylophidae. In combined data analyses, Coccinellidae is recovered as the sister group to Corylophidae. In all analyses, Corylophidae and the subfamily Corylophinae are recovered as monophyletic. The monophyly of Periptyctinae was untested, as only a single species was included. All included corylophine tribes were recovered as monophyletic with the exception of Aenigmaticini; Aenigmaticum Matthews forms the sister group to Orthoperus Stephens and Stanus?lipiński et al. is recovered as the sister group of Sericoderus Stephens. Stanus tasmanicus?lipiński et al. is transferred to a new genus, Pseudostanus Robertson, ?lipiński & McHugh gen.n. incertae sedis. We propose a new tribe, Stanini Robertson, ?lipiński & McHugh trib.n. for Stanus bowesteadi?lipiński et al. and a new concept of Aenigmaticini sensu.n. to include only the nominate genus. Anatomical transitions associated with corylophid miniaturization are highlighted. Key phenotypic modifications and elevated rates of substitution in nuclear rRNA genes are evident in a subgroup of Corylophinae that includes the most diminutive species. Other taxonomic and evolutionary implications are discussed in light of the results. 相似文献
47.
The aerobic capacity model postulates that high basal metabolic rates (BMR) underlying endothermy evolved as a correlated response to the selection on maximal levels of oxygen consumption () associated with locomotor activity. The recent assimilation capacity model specifically assumes that high BMR evolved as a by‐product of the selection for effective parental care, which required long‐term locomotor activity fuelled by energy assimilated from food. To test both models, we compared metabolic and behavioural correlates in males of laboratory mice divergently selected on body mass‐corrected BMR. elicited by running on the treadmill did not differ between selection lines, which points to the lack of genetic correlation between BMR and . In contrast, there was a positive, genetic correlation between spontaneous long‐term locomotor activity, food intake and BMR. Our results therefore corroborate predictions of the assimilation capacity model of endothermy evolution. 相似文献
48.
Katarzyna bagińska Joanna Makowska WiesŁaw Wiczk Franciszek Kasprzykowski Lech ChmurzyńSKI 《Journal of peptide science》2008,14(3):283-289
The circular dichroism (CD) and Fourier transform infrared (FTIR) methods were applied to the conformational studies of alanine-rich peptide Ac-K-[A]11-KGGY-NH2 (where K is lysine, A is alanine, G is glycine and Y is tyrozyne) in water, methanol (MeOH) and trifluoroethanol (TFE). The analysis of CD-spectra of the peptide in water at different concentrations revealed that the secondary structure content depends on the peptide concentration and pH of the solution. The increase of the peptide concentration causes a decrease of alpha-helix content and, simultaneously, an increase of beta-sheet structure, while the unordered structure is the predominant one. Additional elements are discovered in MeOH and TFE but alpha-helix and beta-turns predominate. Moreover, in these solutions the percentage content of the secondary structure does not depend on the temperature. FTIR measurements, carried out at higher peptide concentration (about one order of magnitude) than these CD measurements mentioned above, revealed that in water solution the solid state beta-sheet, and aggregated structures, dominate. However, in TFE the most abundant are alpha-helix and beta-turns structures. The thioflavine T assay showed the tendency of the studied peptide for aggregate. 相似文献
49.
OSKAR SIEMIANOWSKI ANNA BARABASZ ALEKSANDRA WEREMCZUK ANNA RUSZCZYŃSKA EWA BULSKA LORRAINE ELIZABETH WILLIAMS DANUTA MARIA ANTOSIEWICZ 《Plant, cell & environment》2013,36(6):1093-1104
AtHMA4 was previously shown to contribute to the control of Zn root‐to‐shoot translocation and tolerance to high Zn. However, heterologous expression of 35S::AtHMA4 in tobacco (Nicotiana tabacum cv. Xanthi) results in enhanced Zn sensitivity. This study provides a better understanding of the development of this Zn‐sensitive phenotype and demonstrates that substantial modifications of Zn homeostasis occur due to AtHMA4 expression. We show that ectopically expressing AtHMA4 in tobacco results in overloading the root and leaf apoplast with Zn. The tissue and cellular distribution of Zn, monitored using Zinpyr‐1, was altered in the AtHMA4‐expressing plants compared with wild type. Increased loading of the leaf apoplast with Zn in AtHMA4 transformants induced necrosis; this appeared at lower levels of Zn supply in the transgenics compared with wild type. This study suggests that Zn concentration may be sensed in the apoplast of leaves, and if concentrations are above a certain threshold then particular groups of cells accumulate Zn and necrosis is initiated. Therefore, this could be considered as a mechanism for protecting the other parts of the photosynthetically active leaf from Zn toxicity. 相似文献
50.
WOJCIECH WITALIŃSKI 《Invertebrate reproduction & development.》2013,57(2):141-149
The spermatozoa of the mite, Parasitus niveus, are rod-shaped cells possessing a very elongated and zig-zag shaped nucleus. The cytoplasm is filled by so-called “striated bodies” and mitochondria. The plasmalemma forms five complicated structures, called stiff bands. In the peripheral cytoplasm lie flattened canaliculi and flattened cisternae. The morphology of the spermatozoa is compared with that of other mite spermatozoa described in the literature. 相似文献