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81.
Michael J. Benton 《Zoological Journal of the Linnean Society》2016,177(4):813-853
Pareiasaurs were important medium‐ to large‐sized herbivores in the Middle and Late Permian, some 268–252 Ma. They are best known from abundant remains of several taxa found in South Africa and Russia, with isolated finds from other parts of the world. Six genera and species of pareiasaurs have been described from China, and yet they have not been reviewed. Of these six, Tsiyuania may be a synonym of Honania, but this taxon is not further considered here. The other four, which were named for separate finds from the Sunjiagou Formation (Changhsingian, 254–252 Ma), show considerable similarities. Despite earlier suggestions, there are no convincing anatomical characters to distinguish Shihtienfenia, Shansisaurus, and Huanghesaurus, and these three genera are synonymized as Shihtienfenia permica Young & Yeh, 1963. The fourth taxon, Sanchuansaurus pygmaeus Gao, 1989, shows distinctly different teeth from those of Huanghesaurus (= Shihtienfenia), and was about one‐third of the size, so it is retained as a second valid pareiasaur from the Chinese latest Permian. Phylogenetic analysis confirms the validity of these two taxa, with Sanchuansaurus belonging among the derived forms, close to Elginiidae, and with Shihtienfenia associated with Pumiliopareiasauria and Pareiasuchus. 相似文献
82.
Polymeroid trilobite fauna from two stratigraphic sections (Godbondar and Kuhbanan) of the Kuhbanan Formation in northern Kerman (central Iran) were studied and subjected to biostratigraphic analysis. Eleven genera and species are recognised from the latest Early Cambrian and Middle Cambrian Peri-Gondwanian successions of the study sections. The recognised fauna includes Afghanocare lategenatum, Blountia blountia, Iranoleesia sp., Iranoleesia pisiformis, Kermanella kuhbananensis, Kermanella lata lata, Kermanella lata minuta, Kermanella sp., Redlichia chinensis, Redlichia noetlingi and Redlichia sp. Based on trilobite distribution, three trilobite biozones were recognised in the study sections, namely Redlichia noetlingi biozone, Kermanella kuhbananensis biozone and Iranoleesia pisiformis biozone. The age of the study sections is late Early Cambrian to late Middle Cambrian based on the recognised trilobite biozones. The recognised late Early Cambrian trilobite assemblages (especially Redlichia and Kermanella) from northern Kerman are similar to those found from some other parts of Gondwana or Peri-Gondwana terrains (north India, Pakistan, northwestern Kashmir, Tajikistan, South Australia, South China and Afghanistan) and show affinities with fauna found in some other parts of Iran (Alborz, northern Iran; Tabas, eastern Iran; southeast Karman). 相似文献
83.
Lida Xing Martin G. Lockley Jianping Zhang Hendrik Klein Daqing Li Tetsuto Miyashita 《Historical Biology》2016,28(7):881-895
A dinosaur tracksite in the Lower Jurassic Ziliujing Formation of Sichuan Province, China consists of a spectacular sub-vertical exposure, with multiple track-bearing levels and trackways showing parallel and bimodal orientations. Based on well-preserved material, the new ichnogenus and ichnospecies, Liujianpus shunan ichnogen. nov. ichnosp. nov. is erected to accommodate distinctive sauropodomorph trackways occurring in this assemblage. Liujianpus has a unique combination of features, some relating to the early Jurassic basal sauropodomorph (prosauropod in traditional usage) ichnogenus Otozoum, others to the sauropod ichnogenus Brontopodus. Despite such a mix of basal sauropodomorph- and sauropod-like features, the trackmaker of Liujianpus is likely a basal sauropodomorph. This identification is consistent with the occurrence of basal sauropodomorph skeletons from geographically and chronologically close localities. The other distinct morphotype from the tracksite is linked to a sauropod trackmaker. As such, the ichnofauna consisting of two distinct foot morphotypes reflects the diversity of sauropodomorph dinosaurs in the Early Jurassic of Asia. 相似文献
84.
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86.
Raúl O. Gómez Fernando F. Garberoglio Guillermo W. Rougier 《Comptes Rendus Palevol》2019,18(7):771-781
Madtsoiids constitute a successful group of extinct snakes widely distributed across Gondwana and the European archipelago during Late Cretaceous times, surviving in reduced numbers to the Pleistocene. They are renowned for including some of the largest snakes that have ever crawled on earth, yet diverse small madtsoiids are also known. Uncovering the evolutionary trends that led these snakes into disparate body sizes has been hampered mainly by the lack of phylogenetic consensus and the paucity of taxa with novel combinations of features. Here we describe a new large madtsoiid snake based on isolated vertebrae from the La Colonia Formation (Maastrichtian–Danian) of Patagonia, Argentina. A comprehensive phylogenetic analysis recovers Madtsoiidae as a basal ophidian lineage and the new snake as sister to a clade of mostly big-to-gigantic taxa, providing insights into early stages and evolutionary trends towards madtsoiid gigantism. 相似文献
87.
Andrey A. Toropov Alla P. Toropova Giuseppa Raitano Emilio Benfenati 《Saudi Journal of Biological Sciences》2019,26(6):1101-1106
A high level of chromosomal aberrations in peripheral blood lymphocytes may be an early marker of cancer risk, but data on risk of specific cancers and types of chromosomal aberrations are limited. Consequently, the development of predictive models for chromosomal aberrations test is important task. Majority of models for chromosomal aberrations test are so-called knowledge-based rules system. The CORAL software (http://www.insilico.eu/coral, abbreviation of “CORrelation And Logic”) is an alternative for knowledge-based rules system. In contrast to knowledge-based rules system, the CORAL software gives possibility to estimate the influence upon the predictive potential of a model of different molecular alerts as well as different splits into the training set and validation set. This possibility is not available for the approaches based on the knowledge-based rules system. Quantitative Structure–Activity Relationships (QSAR) for chromosome aberration test are established for five random splits into the training, calibration, and validation sets. The QSAR approach is based on representation of the molecular structure by simplified molecular input-line entry system (SMILES) without data on physicochemical and/or biochemical parameters. In spite of this limitation, the statistical quality of these models is quite good. 相似文献
88.
《Palaeoworld》2022,31(4):570-581
Rhynchonelliform brachiopods made their first appearance in early Cambrian, and became a major group within the palaeozoic evolutionary fauna since late Cambrian. Exceptionally preserved fossils from the early Cambrian Lagerstätten provide valuable chances to investigate their phylogeny and ecology. Longtancunella is one of the most interesting early rhynchonelliforms, and has been mainly recovered from the Chengjiang Lagerstätte (Series 2, Stage 3). Here, we report a new rhynchonelliform Longtancunella xiazhuangensis n. sp. from the lower Hongjingshao Formation (upper Stage 3) in Yunnan Province, China. These specimens were well preserved with soft parts, including pinnate mantle canal system and a pedicle. It is identified as a new species based mainly on its difference in shell ornamentations, pinnate mantle canals and pedicle morphology from the type species. Its pedicle looks unusually stout with distinct annulated lamellae on the surface, and reveals crucial evidence in illustrating its ecology and settling strategy as an early marine epifauna. The ecological interaction between L. xiazhuangensis and other marine animals also provides insights into the food web structure in the early Cambrian. 相似文献
89.
Fluorescence properties of Early Cambrian acritarchs were investigated using Leica das Mikroskop (DM) microscopy with a mercury
lamp. Well-preserved autoflurescence properties show a correlation between acritarchs morphology and the intensity of emitted
fluorescence. In accordance with the fluorescence intensity of organic cell walls, two groups of microfossils were distinguished.
Results of observation in this study, which are consistent with those of the previous foreign studies, are in good agreement
with regular difference in autofluorescence intensity among palynomorphs reported by McPhilemy (1998). Spores and algae, including
Botryococcus, have very bright fluorescence while acritarchs often show less intense fluorescence. Dark brown microfossils
have been reworked, and have little or no fluorescence.
__________
Translated from Acta Micropalaeontologica Sinica, 2006, 23(3): 309–312 [译自: 微体古生物学报] 相似文献
90.
Fluorescence properties of Early Cambrian acritarchs were investigated using Leica das Mikroskop (DM)microscopy with a mercury lamp.Well-preserved autoflurescence properties show a correlation between acritarchs morphology and the intensity of emitted fluorescence.In accordance with the fluorescence intensity of organic cell walls,two groups ofmicrofossils were distinguished.Results of observation in this study,which are consistent with those of the previous foreign studies,are in good agreement with regular difference in autofluorescence intensity among palynomorphs reported by McPhilemy (1998).Spores and algae,including Botryococcus,have very bright fluorescence while acritarchs often show less intense fluorescence.Dark brown microfossils have been reworked,and have little or no fluorescence. 相似文献