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941.
ALEXANDER RIEDEL TOMY DOS SANTOS ROLO ANGELICA CECILIA THOMAS VAN DE KAMP 《Zoological Journal of the Linnean Society》2012,165(4):773-794
Two genera of extinct weevils, Sayrevilleus Gratshev & Zherikhin from Cretaceous New Jersey amber and Baltocar Kuschel from Eocene Baltic amber, are recognized as close relatives based on similarities revealed by the use of synchrotron tomography and the availability of new amber inclusions. The subfamily Sayrevilleinae Legalov stat. nov. is characterized by possessing mandibles with an external cutting edge and an inner blunt edge. The subfamily is placed in the family Attelabidae (s.l.), although some characters also suggest a possible relationship with the ‘higher weevils’ comprising Caridae, Brentidae, and Curculionidae. Sayrevilleus is transferred from the tribe Auletini of Rhynchitinae to Sayrevilleinae, and Sayrevilleus grimaldii Gratshev & Zherikhin is redescribed. Baltocar Kuschel is transferred from Caridae to Sayrevilleinae and revised, its type species, Baltocar succinicus (Voss), is redescribed and three new species, Baltocar groehni Riedel sp. nov. , Baltocar hoffeinsorum Riedel sp. nov. , and Baltocar subnudus Riedel sp. nov. are described based on eight well‐preserved inclusions. The genera Orapauletes Legalov and Zherichiniletes Legalov previously assigned to Sayrevilleini are regarded as Curculionoidea incertae sedis. The Sayrevilleinae were distributed over areas of North America and Europe at least since the Late Cretaceous (c. 90 Mya) and were probably relatively diverse until the Eocene (c. 44 Mya). It is speculated that they became extinct through competition with Curculionidae, which used a similar oviposition strategy. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 773–794. 相似文献
942.
James I. Cohen 《Biological journal of the Linnean Society. Linnean Society of London》2012,107(2):442-457
The present study comprises an analysis of six different scoring schemes and eight different types of analytic methods aiming to investigate the evolution of a continuous character (i.e. corolla tube length) in Lithospermum L. (Boraginaceae). Corolla tube length in the genus is quite variable, ranging from 1 mm to 75 mm, and the length of the corolla tube has implications for pollination biology, such as longer corolla tubes (> 25 mm in length) being pollinated by hummingbirds or moths. In general, the various methods resolve similar ancestral character states; however, different states are reconstructed at nodes in which the descendants greatly differ in corolla tube length. Additionally, it is suggested that all of the variation of a continuous character should be included in analyses, and this may necessitate multiple analyses with different partitions of the data. The various analyses provide evidence that two maximum parsimony methods, linear parsimony and the TNT method, minimize the number of different rates of evolution. In Lithospermum, six origins of corolla tubes > 20 mm in length are resolved, and these origins occurred at two different times periods: (1) in the shadow of hummingbird diversification in North America (approximately 6–8 Mya) and (2) more recently (approximately 1–1.5 MyA). Four substantial decreases in corolla tube length also are reconstructed, and these may be associated with the origin of self‐pollination. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ??, ??–??. 相似文献
943.
Heather R. Clendenin Jennifer R. Adams David E. Ausband James A. Hayden Paul A. Hohenlohe Lisette P. Waits 《The Journal of wildlife management》2020,84(3):492-504
Parameters of reproductive success are important to the management of wildlife populations. Genetic monitoring can be an effective approach for acquiring this important demographic information when traditional methods are unsuccessful, inefficient, or too expensive. This study demonstrates a novel application of genetic data opportunistically collected from harvested game to estimate a minimum annual count of breeding packs of gray wolves (Canis lupus) and to provide a coarse index of harvest vulnerability of young of the year (YOY) across packs. We used 18 microsatellite loci to genotype 98 gray wolf YOY from 2014 and 105 from 2015 harvested in Idaho, USA. Using this genotype data, we reconstructed sibling groups for each cohort using the program COLONY and treated full-sibling litters as proxies for unique packs. In addition to evaluating our marker panel using simulations, we assessed the accuracy of empirical relationship assignments by adding YOY of known relationship from long-term study packs to the dataset (27 individuals from 2014 and 61 from 2015) and tracking correctly reconstructed relationships. We varied COLONY input parameters to evaluate the power of relationship assignments under conditions that may be encountered when working with empirical data. We also compared COLONY's estimates of effective number of breeders based on sibship frequency to estimates based on a commonly used linkage-disequilibrium method. All COLONY runs for both cohorts correctly identified the known sibling relationships. Among the other individuals, changes in the geographic clustering of putative siblings, probabilities of inclusion and exclusion for reconstructed sibling groups, and consistency of relationship assignments across COLONY runs suggested that marker number had a larger effect on accuracy than access to population-level genetic data. Our estimates of breeding packs subjected to harvest within the state (52 for 2014 and 63 for 2015) differed from estimates reported by Idaho Department of Fish and Game by ≤6 for both years. Among packs that had pups harvested, most packs had 1–2 YOY harvested, whereas other packs had as many as 5 YOY harvested. All estimates of the number of effective breeders had overlapping confidence intervals regardless of method, though sibship frequency-based estimates had larger confidence intervals than estimates using the linkage disequilibrium method. Our study shows that sibling relationships can be accurately and reliably reconstructed from harvested gray wolves, and demonstrates a valuable new use of samples collected through harvest. © 2020 The Wildlife Society. 相似文献
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945.
946.
R. Van Diggelen A. P. Grootjans R. H. Kemmers A. M. Kooijman M. Succow N. P. J. De Vries G. Van Wirdum 《植被学杂志》1991,2(4):465-476
The Lieper Posse is a calcareous, ground water-fed fen system, situated in the end-moraine area of northeastern Germany. Nowadays the fen is partly drained and the vegetation adversely affected; hence regeneration measures are considered. Here we report a pilot survey of the actual vegetation cover in relation to the hydrological conditions of the system. The vegetation in the central part of the fen system can be assigned to the Caricetum lasiocarpae, with small areas of Eleocharitetum quinqueflorae. The southern part of the system includes a Ledo-Pinetum sylvestris bog. Along the edges eutrophic forest types are present. Peat analysis revealed that the system started as an open lake and subsequently changed into a rheophilous mire, ‘percolating mire’. The southern bog has only recently come into being. Hydrological investigations showed that the original mineral-rich ground water had to a large extent been replaced by acid rainwater; this is likely due to the construction of a ditch before 1850. The effects of this drainage on hydrological conditions and some aspects of soil fertility are discussed. Possible consequences for the restoration of calciphilous vegetation types are being considered. It is concluded that the vegetation development is predictable only to a limited extent, which is mainly due to a lack of knowledge on hysteresis effects in both vegetation and soil. 相似文献
947.
During systematic archaelogical excavations of the early medieval kingdom of Serbia, and adult male skull belonging to the
skeleton of a Roman individual was unearthed at Babrež site in the Ras region. A supernumerary bone was found interposed between
the frontal bones of the skull and the facial skeleton. Paleopathological investigation and CT reconstruction proved that
this skull had been deformed during foetal development due to a disorder or disease affecting the mother. This probably led
to the formation of the supernumerary Glabellar bone in the frontal region. This is the first case of Os Glabellae recorded
so far. 相似文献
948.
Background and Aims
Autoregulation of nodulation is a long-distance shoot–root signalling regulatory system that regulates nodule meristem proliferation in legume plants. However, due to the intricacy and subtleness of the signalling nature in plants, molecular and biochemical details underlying mechanisms of autoregulation of nodulation remain largely unknown. The purpose of this study is to use functional–structural plant modelling to investigate the complexity of this signalling system. There are two major challenges to be met: modelling the 3D architecture of legume roots with nodulation and co-ordinating signalling-developmental processes with various rates.Methods
Soybean (Glycine max) was chosen as the target legume. Its root system was observed to capture lateral root branching and nodule distribution patterns. L-studio, a software tool supporting context-sensitive L-system modelling, was used for the construction of the architectural model and integration with the internal signalling.Key Results
A branching pattern with regular radial angles was found between soybean lateral roots, from which a root mapping method was developed to characterize the laterals. Nodules were mapped based on ‘nodulation section’ to reveal nodule distribution. A root elongation algorithm was then developed for simulation of root development. Based on the use of standard sub-modules, a synchronization algorithm was developed to co-ordinate multi-rate signalling and developmental processes.Conclusions
The modelling methods developed here not only allow recreation of legume root architecture with lateral branching and nodulation details, but also enable parameterization of internal signalling to produce different regulation results. This provides the basis for using virtual experiments to help in investigating the signalling mechanisms at work. 相似文献949.
James F. SMITH 《植物分类学报》2011,49(1)
Chirita D. Don, a large genus in the subfamily Cyrtandroideae of Gesneriaceae, has been the subject of much debate whether it is a natural group or not. In addition, the highly heterogeneous Chirita has also been very problematic with regard to delimitation and subdivision. Here we used the nrDNA internal transcribed spacer and cpDNA trnL-F for molecular phylogenetic analaysis, combined with morphological data. Our results suggest that Chirita is an artificial, polyphyletic genus. The most important charact... 相似文献
950.
HapSTRs combine information from a microsatellite (or simple tandem repeat, STR) with one or more single nucleotide polymorphisms in the DNA sequence immediately flanking the STR. These loci may offer increased power for the estimation of demographic parameters, but also present some challenges for data collection and analysis. We describe a process for inferring HapSTR alleles, including the flanking haplotypes, STR alleles and their phase relative to each other, directly from DNA sequence electropherograms of PCR products from heterozygous individuals. Our approach eliminates the need for more costly and time-consuming processes, such as cloning or acrylamide gel electrophoresis to separate alleles prior to sequencing. 相似文献