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301.
Biochemical constitution of mammalian mitochondria 总被引:21,自引:0,他引:21
SCHNEIDER WC 《The journal of histochemistry and cytochemistry》1953,1(4):212-233
302.
SCHNEIDER JA 《Endokrinologie》1951,28(3-4):161-176
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MARIA C. BLASSIOLI‐MORAES DIEGO M. MAGALHÃES ANDREJ ČOKL RAÚL A. LAUMANN JOSEANE P. DA SILVA CLEONOR C. A. SILVA MIGUEL BORGES 《Physiological Entomology》2014,39(1):1-11
Vibrational communication is important for successful mating in various stink bugs species. The vibrational signals from males and females of Dichelops melacanthus Dallas (Hemiptera: Pentatomidae) are recorded from a nonresonant substrate (i.e. a loudspeaker membrane) to characterize the temporal and spectral properties of these vibrational signals, as well as on a resonant substrate (i.e. bean plants) to obtain information about how these signals are altered when they are transmitted through the plants. On the loudspeaker membrane, D. melacanthus males and females emit only one male or one female song, respectively. However, when the insects are placed on bean leaves, a more complex repertoire is recorded, with three different songs for each sex. The first female and male songs appear to have calling functions and the third male and female songs are emitted during courtship. The second female and male songs are emitted after the first song, although their functions in mating behaviour are not clear. The identified repertoire is similar to those of other Neotropical stink bugs, starting with songs 1 and 2 and developing into song 3. Frequency modulation is observed in the female songs recorded from the loudspeaker membrane and the plants. The signals recorded from plants present higher harmonic peaks compared with the signals recorded from the loudspeaker membrane. The presence of species and sex‐specific songs during mating confirms the important role of vibrational communication in mate location and recognition. The temporal and spectral characteristic signals are influenced by the substrate used to record the songs emitted by D. melacanthus. 相似文献
306.
HARALD SCHNEIDER 《Botanical journal of the Linnean Society. Linnean Society of London》2000,132(1):29-46
The filmy ferns of the tribe Trichomaneae, synonymous with Tichomanes s.L., show various constructions of their root system that correspond to different growth forms as well as ecology. Most terrestrial species possess a short erect shoot with numerous thick roots, whereas epiphytic species have a long creeping rhizome that may develop a few thin roots. An evolutionary progression from ferns with well-developed roots to ferns without roots is postulated. Rootless species occur in two monophyletic groups, subgen. Crepidomanes and subgen. Didymoglossum. The results are summarized in a new classification for the tribe. Secondary simplification, e.g. loss of roots, is discussed as an adaptive trait in epiphytic plants. Transformed structures such as root-like shoots and adhesive hairs are observed in rootless taxa and their evolutionary significance is briefly discussed. Climbing filmy ferns are recognized as possible closely related species based on the similarities in their root systems. 相似文献
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Avise JC; Shapira JF; Daniel SW; Aquadro CF; Lansman RA 《Molecular biology and evolution》1983,1(1):38-56
We address the problem of the possible significance of biological
speciation to the magnitude and pattern of divergence of asexually
transmitted characters in bisexual species. The empirical data for this
report consist of restriction endonuclease site variability in maternally
transmitted mitochondrial DNA (mtDNA) isolated from 82 samples of
Peromyscus polionotus and P. leucopus collected from major portions of the
respective species' ranges. Data are analyzed together with previously
published information on P. maniculatus, a sibling species to polionotus.
Maps of restriction sites indicate that all of the variation observed can
be reasonably attributed to base substitutions leading to loss or gain of
particular recognition sites. Magnitude of mtDNA sequence divergence within
polionotus (maximum approximately equal to 2%) is roughly comparable to
that observed within any of five previously identified mtDNA assemblages in
maniculatus. Sequence divergence within leucopus (maximum approximately
equal to 4%) is somewhat greater than that within polionotus. Consideration
of probable evolutionary links among mtDNA restriction site maps allowed
estimation of matriarchal phylogenies within polionotus and leucopus.
Clustering algorithms and qualitative Wagner procedures were used to
generate phenograms and parsimony networks, respectively, for the
between-species comparisons. Three simple graphical models are presented to
illustrate some conceivable relationships of mtDNA differentiation to
speciation. In theoretical case I, each of two reproductively defined
species (A and B) is monophyletic in matriarchal genealogy; the common
female ancestor of either species can either predate or postdate the
speciation. In case II, neither species is monophyletic in matriarchal
genotype. In case III, species B is monophyletic but forms a subclade
within A which is thus paraphyletic with respect to B. The empirical
results for mtDNA in maniculatus and polionotus appear to conform closely
to case III. These theoretical and empirical considerations raise a number
of questions about the general relationship of the speciation process to
the evolution of uniparentally transmitted traits. Some of these
considerations are presented, and it is suggested that the distribution
patterns of mtDNA sequence variation within and among extant species should
be of considerable relevance to the particular demographies of speciation.
相似文献
310.
This paper describes, not ionic movement, but rather the transferof organic nutrients from environment to cell in microorganisms.A section on methods for studying such transfer is followedby a discussion of generalized models derived from kinetic data.Control mechanisms, involving regulation of synthesis of membraneproteins and feedback modification of their activity, are described.Some recent work on specific models for transport of amino acidsand carbohydrates is also discussed. 相似文献