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51.
目的探讨PAS染色在骨骼肌糖原贮积症诊断中的作用。方法用组织化学方法高碘酸-schiff(periodic acid schiff,PAS)染色方法显示糖原贮积症肌纤维胞浆内糖原的贮积。结果糖原贮积症患者肌纤维胞浆内聚集的红至红紫色颗粒为糖原。结论 PAS染色对于判断细胞内糖原贮积的糖原病和多糖体贮积性疾病的诊断是必要的。  相似文献   
52.
Pascale Gautret 《Geobios》1985,18(5):553-571
The fundamental microstructural and ultrastructuralcaracteristics of a non fibrous carbonate tissue has been revealed by the study of the only living Sphinctozoa: Vaceletia crypta (Vacelet), Demospongia.These observations yield important data for interpretation of homogeneous carbonate structure in the skeleton of some fossil sponges. Effectively, we notice that two triassic forms, morphologically very different (Sphinctozoa and Inozoa) show remarkable microstructural analogies with Vaceletia crypta. These considerations should not be leaved out to establish an only classification of Sponges, joining both living and fossil forms.Moreover, the elementary skeletal constituants ofthe two forms show dimensions which indicate a growth in size in comparison with the living species. This increase has probably a diagenetic origin (adjunction of aragonite). So it appears that the present aspect of the mineral components cannot result from a reduction in size (micritization), as has been sometimes asserted.  相似文献   
53.
海绵的分类、演化及其地质意义   总被引:11,自引:1,他引:10  
张维 《古生物学报》1991,30(6):772-785
本文简述了海绵动物的基本特征,比较了硅质海绵与钙质海绵在骨针及骨骼结构上的不同,认为骨针性质与硬体骨骼结构是海绵分类的主要依据。据此把海绵动物划分为普通海绵纲(Class Demospongea)、六射海绵纲(Class Hexactinellida)、钙质海绵纲(Class Calcispongiae)、异射海绵纲(Class Heteractinida)和硬骨海绵纲(Class Sclerospongiae),并进一步讨论了不同类别海绵在地史时期的分布及演化。提出海绵除可作为判别环境的标志外,还是重要的造礁生物。地史时期由海绵形成的成礁期有3次,它们与不同类型碳酸盐岩隆的生成及油气的聚集有密切关系。  相似文献   
54.
Summary Electron-microscopical autoradiography and cytochemical techniques have been used to identify the distinct and separate subcellular structures involved in the secretion of 1) procollagen, 2) dihydroxyphenylalanine (DOPA), which is a precursor of a collagen-crosslinking compound, and 3) DOPA oxidase, which converts DOPA to a putative crosslinking compound of collagen in the axial skeleton of the gorgonian coral Leptogorgia virgulata. Some skeletal-protein hydrolysates contain material that co-elutes with DOPA. The data indicate that these skeletogenic cells, corticocytes, are capable of modifying the number of non-reducible, tyrosine-derived crosslinkages of collagen by the secretion of a crosslinking compound that acts extracellularly on collagen. A mechanism for a cell-mediated control of the mechanical properties of collagen is thereby presented.  相似文献   
55.
Jean Gaudant 《Geobios》1979,12(1):47-73
«Pachylebias crassicaudus (Agassiz) is a fossilfish widely distributed throughout the continental Messinian of Italy and Crete. Its detailed anatomical study permits the assessment of its systematic status within the subfamily Cyprinodontinae. A new locality with P. crassicaudus is pointed out in Italy, in the vicinity of Bologna. The fact that the same species occurs also in the gypsum deposits of Western Crete (Greece) leads one to suggest that these gypsums are Messinian in age. Finally, the palaeoecological study of P. crassicaudus makes possible the definition of the sedimentation conditions of the sediments belonging to the «gypsumsulphur formation.  相似文献   
56.
Eric Buffetaut 《Geobios》1976,9(2):143-198
Among the abundant remains of Mesosuchia that have been yielded by the early Senonian locality of In Beceten (Niger), the most numerous belong to the species Trematochampsa taquetiBuffetaut, 1974. The osteology of this species is described here. This medium-sized crocodilian, with a moderately elongated skull, is characterized, among other features, by its antorbital fenestra, its surangular-quadratojugal articulation, its slightly displaced post-orbital pillar, its teeth with wrinkled enamel, and its amphicoelous vertebrae. In its general outlook, this animal is rather reminiscent of the Goniopholidae, from the Upper Jurassic and the Cretaceous of Laurasia, but it is more primitive than them, and resemblances are probably due to convergence phenomena. The family Trematochampsidae is probably essentially Gondwanian, and could persist until the Senonian thanks to a certain isolation from Laurasia, where more progressive Crocodylia became predominant much earlier than in Africa and South America.  相似文献   
57.
甘肃鼢鼠骨骼5种常量无机元素测定   总被引:2,自引:2,他引:0  
用原子吸收分光光度计、可见光分光光度计对甘肃鼢鼠(Myospalax cansus)骨骼中Ca、K、Na、Mg、P 5种常量无机元素作了测定。结果表明,甘肃鼢鼠骨骼中5种元素含量依次为Ca>P>K>Na>Mg,Ca含量维持较高水平;同一元素在不同部位骨骼的含量存在差异,部分含量差异显著,5种元素总量在不同部位骨骼的分布顺序为:后肢骨>前肢骨>脊柱;根据甘肃鼢鼠骨骼Ca与P比值推断二者主要以羟基磷灰石形式存在。  相似文献   
58.
Gerard R. Case 《Geobios》1978,11(1):21-29
Toothplates of the ratfish Ischyodus are rather common fossils, distributed throughout the Campanian-Maestrichtian of New Jersey and Delaware although heretofore unrecognized or described. A new species of Ischyodus differs from the European species, I. thurmanniPictet & Campiche and I. dolloiLeriche, by the fusion of the median and internal posterior tritors of the mandibular apparatus. Except in rare individuals the palatine elements of I. bifurcatus do not show any fusion of their tritoral aspects. The vomerine elements show no distinctive features that could separate them from of any of the known Ischyodus species, and the dorsal fin spine is not significantly different from those of other known chimaeroid fishes, including Edaphodon, Elasmodus, Elasmodectes and Leptomylus. Ischyodus bifurcatus is erected as a new species based upon the bifurcated appearance of the fused mandibular tritors. A temporal range from late Santonian to medial Maestrichtian is indicated by occurrences in Belgium, California, Montana, Arkansas, and Delaware as well as New Jersey.  相似文献   
59.
It is well established that aging of the human skeleton includes the loss of bone mass or density, but little comparative information on age-related osteopenia in other primates is available. In order to determine whether bone loss occurs in normally locomoting nonhuman primates, radiographs of 139 rhesus monkey skeletons from the Cayo Santiago collection were examined, and measures of percent cortical bone (PCT) at the midshaft of second metacarpals, humeri, and femora were calculated. An age-related osteopenia was observed in the metacarpal of adult female macaques, although much individual variation was present. This variability could not be explained by reproductive history (number of offspring), matrilineal affiliation, or degree of osteoarthrosis. However, in a subsample of 15 animals, females who had given birth in the three months prior to death showed lower PCTs than those who had not conceived in the previous mating season. In adult males, PCT did not vary significantly with age, but males that weighed less and those with no/little osteoarthrosis showed lower PCTs than heavier or more arthritic animals, respectively. The multifactorial nature of the variation in PCT observed here suggests that similar processes of bone behavior are involved in the skeletal aging of both humans and rhesus monkeys.  相似文献   
60.
山东山旺Palaeomeryx化石的初步研究   总被引:2,自引:1,他引:1  
Palaeomeryx 在含义、性质和分类位置上,一直是一个争论较多的属.最近在山旺发现的 Palaeomeryx 完整骨架,为解决上述问题提供了有价值的资料和证据. Palaeomeryx 雄性具有一对眶上"皮骨角"和单一的"枕顶角".根据共近裔性状的分析,本文作者认为 Palaeomeryx 应该归入长颈鹿,作为这一支中最早分出的一个旁支.长颈鹿和鹿科有较近的亲缘关系,而和牛科的关系较远. Palaeomeryx 大概位于 Blastomeryx 和 Leptomeryx 之间,从反刍类主干中分出.山旺的材料,代表本属中一个较原始的新种: Palaeomeryx tricornis. 它的时代,可能相当于欧洲的 MN4 或 MN5.  相似文献   
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