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51.
Serge Legendre 《Geobios》1980,13(6):839-847
The occurrence of an emballonurid bat is revealed within the micromammalian fauna found at the Lower Miocene locality of Port-la-Nouvelle (Aude). The material is described, and the comparison with homologous elements of fossil and living Emballonuridae indicates a modern character of the teeth.This species could be related to the recent genusTaphozous.. Therefore, a new family is added to the Western European mammalian Neogene fauna; and the Neogene geographical area of this family, previously limited to East Africa, is now extended to Europe.  相似文献   
52.
Diagnosis: number of fins rays D1: VI; D2: I+ 9; C: 21-22; A: I+ 8; P: 17-18; Pv: 10; number of scales on the lateral line Ec: 27-28; number of vertebras V: 26. Evidence of sexual dimorphism is shown by two different shapes of urogenital papilla. The lateral system was observed using scanning electron microscopy after 2% glutaraldehyde fixation in sea water. The oculoscapular, preopercular canals, mucous pores are inventoried and the distribution and number of neuromasts are presented. The coding sequences for 18S ribosomic RNA are identified.  相似文献   
53.
采用RACE技术从忽地笑也Lycoris aurea ( L'Hér.) Herb.页叶片中克隆获得γ-生育酚甲基转移酶(γ-TMT)基因,命名为LaTMT。序列分析结果显示:该基因cDNA全长1458 bp,其中开放阅读框( ORF)长1017 bp,编码338个氨基酸残基。 LaTMT基因编码蛋白质的理论相对分子质量37560,理论等电点pI 8.70,为亲水性蛋白,无跨膜结构但具有信号肽结构;并具有S-腺苷甲硫氨酸( SAM)甲基转移酶保守结构域,包含3个SAM结合位点;该蛋白的二级结构中包含44.08%的α-螺旋、32.84%的无规则卷曲、12.72%的延伸链和10.36%的β-转角。序列比对和系统进化树分析结果显示:LaTMT蛋白属于S-腺苷甲硫氨酸-依赖性γ-生育酚甲基转移酶家族,与其他植物γ-TMT蛋白的一致性为64%~75%;在 NJ系统树上, LaTMT蛋白与单子叶植物γ-TMT蛋白聚为同一大类,并与油棕( Elaeis guineensis Jacq.) EgTMT和美洲油棕也Elaeis oleifera ( Kunth) Cortés页EoTMT聚为同一类,亲缘关系最近。基因表达分析结果显示:LaTMT基因可在大肠杆菌中成功表达,且表达量随异丙基硫代半乳糖苷( IPTG)诱导时间的延长而增加;在忽地笑的根、叶片、花苞、子房、雄蕊、花瓣和鳞茎中LaTMT基因均可表达,其中在叶片中的相对表达量最高,在子房、雄蕊和鳞茎中的相对表达量相对较低,具有明显的组织特异性。研究结果表明:忽地笑LaTMT基因在进化过程中具有很高的保守性;该基因主要定位于叶绿体中,并与忽地笑对非生物逆境胁迫的抗性相关。  相似文献   
54.
55.
《Comptes Rendus Palevol》2013,12(6):381-387
I propose an approach to identify, among several strategies of phylogenetic analysis, those producing the most accurate results. This approach is based on the hypothesis that the more a result is reproduced from independent data, the more it reflects the historical signal common to the analysed data. Under this hypothesis, the capacity of an analytical strategy to extract historical signal should correlate positively with the coherence of the obtained results. I apply this approach to a series of analyses on empirical data, basing the coherence measure on the Robinson–Foulds distances between the obtained trees. At first approximation, the analytical strategies most suitable for the data produce the most coherent results. However, risks of false positives and false negatives are identified, which are difficult to rule out.  相似文献   
56.
We address the phylogenetic relationships of ten passerine bird species representing the five presently supposed monarchine (family Monarchidae) genera (Terpsiphone, Hypothymis, Elminia, Trochocercus, Erythrocercus) from Asia and Africa, as well as three monarchs from Australasia, three representatives of the related genera Rhipidura and Dicrurus, and 20 representatives of 11 other oscine groups (including two Culicicapa flycatchers) and one sub-oscine, using two partial mitochondrial genes (cytochrome b and large sub-unit ribosomal 16S RNA). Molecular data corroborate ecological, ethological and morphological observations on the probable heterogeneity of Trochocercus and indicate that this genus is polyphyletic; two of its species are members of Monarchidae allied to Terpsiphone and Hypothymis; the others are more closely related to Elminia. Elminia is not a member of Monarchidae and is not related to any other sampled species, except Culicicapa. Erythrocercus is also outside the Monarchidae but inside a Sylvii-Pycnonotidae group. These results point once more to the need of a fully revised phylogeny of passerine birds.  相似文献   
57.
莫建初  周丽君 《昆虫知识》1995,32(2):100-102
用上年受害树和未受害树的当年新发叶在室内饲养油桐尺蠖幼虫,并用Folin-Denis分析方法测定了当年受害叶,受害后新发叶和未受害叶的总单宁含量。结果表明,取食受害叶的幼虫比取食未受害叶者存活率低20.5%,发有速度慢2天,体长短5.0mm,蛹重轻25.3%。叶内总单宁含量不因受害而上升,反而呈下降趋势,说明叶内成分中影响幼虫生长发育的是非单宁物质。  相似文献   
58.
A fossil feather preserved as a carbonised trace is described from the Tomaj Limestone at Kri , in the Kras region of southwestern Slovenia. The Tomaj Limestone is a platy and laminated limestone with cherts, which occurs within a well-bedded rudist limestone of the Santonian–Campanian Lipica Formation. It was deposited in a lagoon environment and has yielded a diverse fossil assemblage. Whether this feather belonged to a bird or to a dinosaur is unclear, but it is an addition to the scanty record of Late Cretaceous feathers, from a palaeobiogeographically interesting area.  相似文献   
59.
《Annales de Paléontologie》2017,103(2):113-125
The first known fossil specimens of pipehorses (Haliichthyinae) were unearthed from the Middle Miocene (Sarmatian) beds of the Coprolitic Horizon in the Tunjice Hills, Slovenia. These fossil pipehorses belong to a new genus and species Hippohaliichthys edis, which was similar to the extant species Haliichthys taeniophorus. The body morphology indicates that the described fossil pipehorses were also closely related to the pygmy pipehorse Hippotropiscis frenki and the seahorse Hippocampus sarmaticus, two taxa which were also found in the Coprolitic Horizon. The described fossil material of pipehorses indicates that seahorses evolved from a group of pipehorses that were similar in size and shape to extant and fossil pipehorses of the Haliichthyinae subfamily.  相似文献   
60.
Bart Kahr 《Chirality》2020,32(5):652-660
Aimé Cotton is known for his invention of circular dichroism spectroscopy. In 1913, he married Eugénie Feytis, a scientist who studied physics with Marie Curie. Following the Second World War, Eugénie Cotton was determined to advance the rights and standing of women, sure in the belief that doing so was necessary not only because it was just but also because a world with women in the forefront would be more secure and less susceptible to the catastrophe worldwide military conflict. She was a cofounder of the Women's International Democratic Federation and served as its first president. In 1951, she was awarded the Stalin Peace Prize, and in 1961, the gold medal from the World Peace Council. The extraordinary life of Eugénie Cotton is reconstructed in a new biography by Loukia Efthymiou, Eugénie Cotton (1881-1967) (Éditions Universitaires Européennes, 2019) that is reviewed here. Among the contributions of Eugénie Cotton of particular interest to the Chirality readership is the biography she wrote of her husband, Aimé Cotton, l'optique et magneto-optique (Éditions Seghers, 1967), the most complete source of information on the founder of the science of circular dichroism. This biography is also discussed here, thereby building two reviews of books, one new and one old, one about Eugénie Cotton and one by her, into a single essay.  相似文献   
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