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61.
Grellia gen. n. is established for the genus Eucoccidium of Grell (1953) preoccupied, and the classification of the apicomplexan order Protococcidiorida Kheisin, 1956 is reviewed, giving diagnoses, type species and a list of species. Grelliidae fam. n. is established for the genera Grellia, Coelotropha, Myriosporides and Defretinella.  相似文献   
62.
The symbiotic dinoflagellate Gymnoxanthella radiolariae T. Yuasa et T. Horiguchi gen. et sp. nov. isolated from polycystine radiolarians is described herein based on light, scanning and transmission electron microscopy as well as molecular phylogenetic analyses of SSU and LSU rDNA sequences. Motile cells of G. radiolariae were obtained in culture, and appeared to be unarmored. The cells were 9.1–11.4 μm long and 5.7–9.4 μm wide, and oval to elongate oval in the ventral view. They possessed an counterclockwise horseshoe‐shaped apical groove, a nuclear envelope with vesicular chambers, cingulum displacement with one cingulum width, and the nuclear fibrous connective; all of these are characteristics of Gymnodinium sensu stricto (Gymnodinium s.s.). Molecular phylogenetic analyses also indicated that G. radiolariae belongs to the clade of Gymnodinium s.s. However, in our molecular phylogenetic trees, G. radiolariae was distantly related to Gymnodinium fuscum, the type species of Gymnodinium. Based on the consistent morphological, genetic, and ecological divergence of our species with the other genera and species of Gymnodinium s.s., we considered it justified to erect a new, separate genus and species G. radiolariae gen. et sp. nov. As for the peridinioid symbiont of radiolarians, Brandtodinium has been erected as a new genus instead of Zooxanthella, but the name Zooxanthella is still valid. Brandtodinium is a junior synonym of Zooxanthella. Our results suggest that at least two dinoflagellate symbiont species, peridinioid Zooxanthella nutricula and gymnodinioid G. radiolariae, exist in radiolarians, and that they may have been mixed and reported as “Z. nutricula” since the 19th century.  相似文献   
63.
A new genus and species Hula recurvata is described from the Posong-chong Formation (Siegenian) of Lower Devonian in Wenshan district, Yunnan, China.This plant possesses pseudomonopodial and dichotomous axes with terminal spikes andit sometimes has single sporangia below the branching point within the fertile regions.Sporangia with stalks are ovate, adaxially recurved and downwards and spirally arrangedon the axis of the spike. Protostele is centrarch. The characteristics stated above showthe new plant has close affinity to Taeniocrada decheniana, but it differes from the members of any other rhyniophytes as well as zosterophyllophytes. A new family——Taeniocradaceae can be established and is provisionally assigned to Rhyniophytina. Evolutionary line of early land-plants, from Rhyniaceae to Taeniocradaceae and then to Bari-nophytaceae is discussed in this paper.  相似文献   
64.
A new Monosulcate pollen has been discovered from the upper partof Lower Cretaceous deposits of Hubei, Jiangsu, Jingxi and Hebei Provinces. Thesepollens have a monosulcate on their distal surface with salient features and differ fromCycadopites and Benettites. We call them Zhonghuapollis gen. nov. They are widespread geographically and only restricted to the later Early Cretaceous deposits, so very useful in stratigraphical dividing and correlation of this deposits.  相似文献   
65.
The new damselfly genus and species Valerea multicellulata is described from the Paleocene of Menat (France), a Lagerstatte with many fossil insects, plants and vertebrates with high paleontological value. Aquatic insects are very scarce in this outcrop, this damselfly being the fourth described Odonata. Its closest modern relatives belong to the Amphipterygidae or the Devadattidae, families with very narrow tropical extant distributions. This new fossil allows us to confirm the tropical affinities of the odonatan fauna of the Menat paleolake communities. It also shows that the amphipterygids were clearly more widespread during the Paleogene than today, probably in relation to the worldwide warm and equable climate in the Paleocene.

http://zoobank.org/urn:lsid:zoobank.org:act:3F631097-DE0B-40FA8227-9C12F55DBAB4  相似文献   

66.
《Annales de Paléontologie》2017,103(2):141-147
A small bird with a shorebird-like beak and a very long hind toe is described from the Early Eocene of Messel in Germany. Vanolimicola longihallucis, gen. et sp. nov. is one of the few candidate species for a “wading bird” from Messel, that is, a bird that may have foraged along the shoreline of the ancient lake. A few features indicate a relationship to charadriiform birds and Jacanidae (jacanas) in particular, but charadriiform affinities are only weakly supported. In the preserved skeletal elements, V. longihallucis also resembles the taxon Songzia from the Early Eocene of China, which is considered to be a representative of the Ralloidea (rails and allies). A potential biogeographic significance of the new Messel fossil is strengthened by similar fossils from the North American Green River Formation.  相似文献   
67.
68.
Triangulamyxa amazonica n. gen. and n. sp. (Myxozoa, Ortholineidae), found in the lumen of the intestine of the freshwater fish Sphoeroides testudineus, is described. The fish were collected from the Amazon River near the city of Algodoal, State of the Pará, Brazil. Numerous irregular plasmodia containing different stages of sporogony, including spores, were observed. The plasmodia were lying free in the lumen or had slender pseudopodia-like cytoplasmic processes in contact with intestinal epithelial cells with microvilli projections. Spores, which are equilaterally triangular in valvar view with rounded pointed ends and ellipsoidal in transverse section, are 8.5 μm long, 7.6 μm wide, and 3.8 μm thick. The anterior end of the spores contains two equal drop-shaped polar capsules measuring 2.6 μm in length, each having an isofilar polar filament with 5–6 turns. The characteristics of the spore shape, the spore wall structure and its ridge organization, the plasmodial characteristics and the identity of the host suggest that the parasite is a new genus and species, which is herein designated T. amazonica.  相似文献   
69.
One of the basal Glyptodontidae groups is represented by the Propalaehoplophorinae (late Oligocene — middle Miocene), whose genera (Propalaehoplophorus, Eucinepeltus, Metopotoxus, Cochlops, andAsterostemma) were initially recognized in Argentinian Patagonia. Among these,Asterostemma was characterized by its wide latitudinal distribution, ranging from southernmost (Patagonia) to northernmost (Colombia, Venezuela) South America. However, the generic assignation of the Miocene species from Colombia and Venezuela (A.? acostae, A. gigantea, andA. venezolensis) was contested by some authors, who explicitly accepted the possibility that these species could correspond to a new genus, different from those recognized in southern areas. A new comparative study of taxa from Argentinian Patagonia, Colombia and Venezuela (together with the recognition of a new genus and species for the Pliocene of the latter country) indicates that the species in northern South America are not Propalaehoplophorinae, but represent the first stages in the cladogenesis of the Glyptodontinae glyptodontids, the history of which was heretofore restricted to the late Miocene — early Holocene of southernmost South America. Accordingly, we propose the recognition of the new genusBoreostemma for the species from northern South America and the restriction ofAsterostemma to the Miocene of Patagonia. Thus, the available data indicate that the Glyptodontinae would in fact have arisen in the northernmost regions of this continent. Their arrival to more southerly areas coincides with the acme of the “Age of Southern Plains”. The Propalaehoplophorinae are geographically restricted to Patagonia.  相似文献   
70.
对最近分离到的一株能合成维生素C前体 - 2 -酮基 -L -古龙酸 (2 -KGA)的新产酸菌V6生物学和分子生物学特性进行了初步研究。该菌株为革兰氏阴性菌 ,细胞为短杆状 ,菌体大小为 0 .8- 1.0× 0 .4 - 0 .6 μm ,菌落为淡黄色 ,好氧 ,最适生长温度为 2 8~ 30℃ ,最适pH为 7.0~ 7.8,GCmol%含量为 5 3.1% ,不含质粒 ,能氧化葡萄糖、山梨醇和山梨糖合成 2 -KGA。 16SrDNA同源性分析发现 ,该产酸菌与以前报道的能合成 2 -KGA的三个属Ketogulonigenium属、Gluconobacter属和Acetobacter属的同源性分别是 98.9~ 99.3%、82~ 83%和 81~ 82 %。基于以上特性分析 ,该产酸菌在分类发育学上宜归为Ketogulonigenium属。  相似文献   
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