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1.
This study evaluated the relative ability of various combinations of copper sulfate with either boric acid or calcium-precipitating agent, N′-N-(1, 8-naphthalyl) hydroxylamine (NHA-Na), to inhibit fungal degradation and attack by Formosan subterranean termites (Coptotermes formosanus Shiraki). Wood specimens were treated with either 1%, 0.5%, or 0.1% concentrations of copper sulfate, boric acid, NHA-Na, copper sulfate + boric acid, or copper sulfate + NHA-Na mixtures. Treated specimens were subjected to laboratory decay-resistance tests by using petri dishes inoculated with the Basidiomycetes fungi Tyromyces palustris and Trametes versicolor for 12 weeks. Treated wood specimens were also subjected to termite-resistance tests under laboratory conditions. Increased efficacy of copper sulfate against the brown-rot fungus T. palustris was observed when either boric acid or NHA-Na was added. The most effective treatments against the fungi tested were NHA-Na only treatments at 1% and 0.5% concentration levels. Boric acid treatments were not able to protect wood against decay after leaching because of excessive leaching of boron. Similar results were obtained in termite-resistance tests in comparison with decay-resistance tests. These results indicate that the efficacy of the treatments in preventing fungal and termite attack is a function of the type of preservative.  相似文献   
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Details of the cuticular, epidermal and anatomical features of the leaves of Cathaya argyrophylla Chun & Kuang, are described and compared with those of three species of Keteleeria (K. davidiana (Bertrand) Beissner, K. fortunei (Murray) Carriere, and K. chien-peii Flous). The study supports the creation of Cathaya Chun & Kuang as a new genus of the Pinaceae.  相似文献   
5.
In view of their propositional content (i.e. they can be right or wrong), character statements (i.e. statements that predicate characters of organisms) are treated as low-level hypotheses. The thesis of the present study is that such character statements, as do more complex scientific theories, come with variable scope. The scope of a hypothesis, or theory, is the domain of discourse over which the hypothesis, or theory, ranges. A character statement is initially introduced within the context of a certain domain of discourse that is defined by the scale of the initial phylogenetic analysis. The doctrine of 'total evidence' requires the inclusion of previously introduced characters in subsequent studies. As a consequence, the initial scope of character statements is widened to the extent that the scale of subsequent analyses is broadened. Scope expansion for character statements may result in incomplete characters, in the subdivision of characters, or in ambiguity of reference (indeterminacy of the extension of anatomical terms). Character statements with a wide scope are desirable because they refer to characters with the potential to resolve deep nodes in phylogenetic analyses. Care must be taken to preserve referential unambiguity of anatomical terms if the originally restricted scope of a character statement is expanded to match a broad-scale phylogenetic analysis.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 92 , 297–308.  相似文献   
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Four collections of three species ofTrimenia and one collection ofPiptocalyx were studied; early-formed and later-formed wood was analyzed for oneTrimenia. Liquid-preserved material permitted analysis of mucilage and starch storage in wood ofT. neocaledonica andP. moorei. BecausePiptocalyx is scandent whereasTrimenia is arborescent, wood differences relative to evolution of a climbing habit could be examined.Piptocalyx contrasts withTrimenia in having wider vessels, more numerous per mm2, resulting in a conductive area five times greater per unit area than that of theTrimenia woods averaged.Piptocalyx has appreciably fewer bars per perforation plate and thus much greater conductive area per perforation plate than have the species ofTrimenia. Rays inPiptocalyx are much taller and wider than those ofTrimenia. Wood ofTrimeniaceae is highly primitive in its scalariform perforation plates, scalariform lateral wall pitting on vessels, relatively long vessels elements, and heterocellular rays. Imperforate tracheary elements are septate nucleate fibertracheids (or even libriform fibers) rather than tracheids, but loss of borders on pits (and thus lowered conductive function of the imperforate tracheary elements) can be explained by the development of these elements into starchstoring cells. Some fiber-tracheids inT. neocaledonica are enlarged mucilagecontaining cells. Details of vessel structure inTrimeniaceae are similar to those ofMonimiaceae (s. s.), but similarity to some other lauralean (annonalean) families may be found: in mucilage presence,Trimeniaceae resembleLauraceae rather thanMonimiaceae. Wood ofTrimeniaceae may be regarded as highly mesomorphic, corresponding to the moist habitats in which all of the species occur.  相似文献   
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The remarkable diversity of fruits inValerianella andFedia is revealed by a comparative morphological and anatomical analysis. Characters are evaluated in regard to a new systematic grouping. The knowledge on dispersal biology is summarized and supplemented. Finally, salient features of fruit differentiation are discussed.
3. Teil der Publikationsserie Beiträge zur Systematik und Evolution vonValerianella undFedia (Valerianaceae) (vgl.Ernet 1977a, b).  相似文献   
8.
The aberrant features of the genus Daubentonia, such as the superficially rodent-like dentition, the globose and foreshortened brain case, and the filiform third manual digit have long been known. But the current assessment of the genus as lemuriform, and within that group as closest to the indriids, depends upon greater weight being placed upon other characteristics such as the cranial arterial pattern, the molariform teeth, and the developmental characteristics of the dentition. Prior multivariate morphometric studies have shown that though the shoulder structure of Daubentonia is uniquely different from that of all other primates, the structure of its pelvis may not be especially different from that of many relatively non-specialized primates. A large series of studies have been summated here in which many different anatomical regions (shoulder, arm, forearm, forelimb as a whole, pelvis, femur, hindlimb as a whole, forelimb and hindlimb combined, and total bodily proportions including limbs, trunk, and head) have been characterized osteometrically in a wide range of primate genera. The resulting data sets have been studied by discriminant function analyses. The differences that have been found are large enough that it can be confidently asserted that in its postcranial skeleton, Daubentonia is more different from the primates as a whole than is any other primate genus. These differences are big enough that their statistical and biological significance is not at all in doubt, notwithstanding the very small numbers of available specimens of this rare genus. They are so great that functional implications exist though they cannot, in our present state of knowledge of the habits of the genus, be ascribed with any certainty. They are so great indeed, paralleling the enormous differences of Daubentonia from other primates in its dentition, skull and cheiridia, that we may prefer to keep open minds about its taxonomic placement.  相似文献   
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One of the most complete skulls of the early primate Adapis parisiensis is in the collection of the Department of Zoology, Cambridge University. This exceptionally well-preserved male skull, from Quercy in southern France, is important in showing relatively small orbits that are highly convergent, a distinct ethmoid component in the medial orbital wall, very small infraorbital foramina, a well-preserved auditory region with the stapedial canal about twice the diameter of the canal for the promontory artery, and a well-preserved braincase 8.8 cm3 in endocranial volume. The frontal lobe of the brain in the Cambridge skull described here is less expanded than that reported previously in a British Museum skull. The average body weight of Adapis parisiensis is estimated to have been about 2.0 kg, and that of Adapis magnus is estimated to have been about 8.4 to 9.0 kg. The encephalization quotient (EQ) of Adapis parisiensis is estimated to have been 0.45, which is well below the range found in modern prosimians. There is some indication that the size of the foramen magnum has increased with increasing brain size during primate evolution. Adapis parisiensis appears to have been a medium-sized, visually oriented, diurnal, sexually dimorphic arboreal folivore.  相似文献   
10.
An integumental anatomy for the lycaenid butterfly Glaucopsyche lygdamus is presented. Comparisons with other lepidopteran taxa are made to rectify the homology of parts and contrast anatomical divergences within the Lycaenidae. A general terminology based on Snodgrass is given, to replace many of the specialized and often synonymous terms restricted to the Lepidoptera. Many common anatomical svnonyms are also given. Several reinterpretations of the anatomy and homology of various integumental regions are discussed. A previously unreported cuticular anomaly on abdominal tergum 2 of male Polyommatinae (Downey's area) is described. The following new or newly combined terms are used:postgenal-occipital area, postgenal-occipital protuberance, dorsal temporal sulci, postantennal projections, pronotal projection, infraepisternal-basisternal plate, paracoxal-marginopleural sulci, dorsal epimeral sulci, ventral epimeral sulci, secondary coxal sulci, ventral subcostal-radial process, lateral secondary sclerite and Downey's area.  相似文献   
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