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71.
72.
A poorly known threadfin, Polynemus melanochir Valenciennes in Cuvier and Valenciennes, 1831, is redescribed (as P. melanochir melanochir) on the basis of a newly designated neotype and a large number of specimens. Polynemus melanopus Sauvage, 1881 and 3 species commonly regarded as valid, Galeoides microps Steindachner, 1869, P. borneensis Bleeker, 1857, and Trichidion hilleri Fowler, 1905, are all considered junior synonyms of P. m. melanochir. In addition, a new subspecies, P. melanochir dulcis, is described on the basis of 3 specimens. Polynemus m. dulcis differs from P. m. melanochir in having a greater snout length [7% of SL vs. mean 6% (range 5–6%) of SL in the latter] and shorter upper caudal-fin lobe
length [35% (34–35%) of SL vs. 39% (35–44%) of SL]. The former is currently known only from Tonle Sap Lake, Cambodia, whereas
the latter is known from the Mekong River (Cambodia and southern Vietnam) and Kalimantan (=Borneo; Malaysia and Indonesia).
Received: September 27, 2001 / Revised: December 20, 2001 / Accepted: December 29, 2001 相似文献
73.
对产于西藏东南部察隅和墨脱的察隅棘蛙通过形态特征和数值分类作了进一步比较研究,结果认为:产于察隅的察隅棘蛙是一个有效种,而产于墨脱的标本应为一个新种,即墨脱棘蛙Paa medogensis sp.nov.。 相似文献
74.
David Sánchez Magdalena Mulet Ana C. Rodríguez Zoyla David Jorge Lalucat Elena García-Valdés 《Systematic and applied microbiology》2014
Strains VGXO14T and Vi1 were isolated from the Atlantic intertidal shore from Galicia, Spain, after the Prestige oil spill. Both strains were Gram-negative rod-shaped bacteria with one polar inserted flagellum, strictly aerobic, and able to grow at 18–37 °C, pH 6–10 and 2–10% NaCl. A preliminary analysis of the 16S rRNA and the partial rpoD gene sequences indicated that these strains belonged to the Pseudomonas genus but were distinct from any known Pseudomonas species. A polyphasic taxonomic approach including phylogenetic, chemotaxonomic, phenotypic and genotypic data confirmed that the strains belonged to the Pseudomonas pertucinogena group. In a multilocus sequence analysis, the similarity of VGXO14T and Vi1 to the closest type strain of the group, Pseudomonas pachastrellae, was 90.4%, which was lower than the threshold of 97% established to discriminate species in the Pseudomonas genus. The DNA–DNA hybridisation similarity between strains VGXO14T and Vi1 was 79.6%, but below 70% with the type strains in the P. pertucinogena group. Therefore, the strains should be classified within the genus Pseudomonas as a novel species, for which the name Pseudomonas aestusnigri is proposed. The type strain is VGXO14T (=CCUG 64165T = CECT 8317T). 相似文献
75.
Fossil testudinids are known in Europe since the Eocene, with several taxa of medium size (from more than 0.3 m to less than 0.7 m) recognized in the Palaeogene record, most of them being poorly known. The size of several European Neogene taxa was larger (between 1 and 2 m). These large testudinids were relatively abundant and diverse, ranging from the early Miocene to the Pleistocene. However, there is a nomenclatural gap at the generic level for the Neogene forms, as their generally used assignment to the more primitive Eocene Cheirogaster cannot be sustained. This is because relatively little material has been assigned to the described species, and also because of the absence of a detailed study comparing all of the European taxa. Here, the European Cenozoic taxa are incorporated for the first time in a data matrix, so that a hypothesis on their phylogenetic relationships is justified. This study identified the large testudinids from the Neogene of Europe as belonging to a monophyletic clade, assigned to the new genus T itanochelon . The hitherto poorly understood ‘Testudo’ bolivari, proposed nearly a century ago but lacking diagnosis, is analysed in detail. It is recognized as the best‐represented large testudinid from the European record, and is identified as the type species of T itanochelon gen. nov. Its comparison with the other Neogene species allowed a detailed study of the new genus and an analysis of its phylogenetic relationships with the other European taxa. © 2014 The Linnean Society of London 相似文献
76.
Urstylidae – a new family of abyssal isopods (Crustacea: Asellota) and its phylogenetic implications
Torben Riehl George D. F. Wilson Marina V. Malyutina 《Zoological Journal of the Linnean Society》2014,170(2):245-296
We report three new species of isopod crustaceans that belong to a rare higher taxon of asellote Isopoda. This taxon does not fit into current classifications. The isopods occurred in abyssal soft sediments, near manganese nodules, and in the vicinity of hydrothermal vents. Given their wide spatial occurrence across the Atlantic and Pacific Oceans, a cosmopolitan distribution is assumed. A cladistic analysis revealed a close relationship with the Macrostylidae, a common representative of the deep‐sea macrofauna. Analyses of character evolution across the Janiroidea showed sufficient synapomorphies to justify the erection of U rstylis gen. nov. and the new family Urstylidae based on the three new species. All taxa are described in this paper. Urstylidae is characterized, amongst other apomorphies, by an elongate habitus with spade‐like head; uropods are long, styliform; one pleonite is free; antennal merus and carpus are relatively short; the first pereopod is carpo‐propodosubchelate, and more robust and shorter than pereopod II. Several characters, such as the pereopods’ posterior scale‐like claw that basally encloses the distal sensilla may be interpreted as ancestral when compared to the situation in the highly derived Macrostylidae. © 2014 The Linnean Society of London 相似文献
77.
78.
79.
A new bitterling, Rhodeus pseudosericeus sp. nov., is described on the basis of 31 specimens from five localities included in the Namhan River system, South Korea.
The new species is distinguished from other Rhodeus species by the following combination of characters: branched dorsal fin rays 9–10 (mode 9); branched anal fin rays 9–11 (mode
10); longest simple ray of dorsal fin strong and stiff, distally segmented; pelvic fin rays i, 6–7; iris of males blackish;
dorsal and anal fins of males grayish in breeding season; karyotype with 2n = 48 (8m + 20sm + 20st). Rhodeus pseudosericeus sp. nov. is similar to Rhodeus sericeus sericeus in the number of pelvic fin and branched dorsal fin rays and the melanophores present on the dorsal fin membrane, but differs
from the latter in having a greater body depth, more branched anal fin rays, fewer vertebrae, a lower number of scales in
the lateral series, and differing male nuptial coloration.
Received: June 30, 2000 / Revised: February 21, 2001 / Accepted: March 6, 2001 相似文献
80.
Nominal Polydactylus species characterized by a large black spot anteriorly on the lateral line, P. microstomus (Bleeker), P. sextarius mullani (Hora), P. sextarius sextarius (Bloch and Schneider), and P. zophomus Jordan and McGregor, are reviewed. Polydactylus zophomus, with 5 pectoral filaments, is synonymized under P. microstomus, and P. sextarius mullani, with 7 pectoral filaments, is elevated to species level (as P. mullani). Polydactylus microstomus and P. mullani together with P. sextarius (characterized by 6 pectoral filaments) are considered as valid species and redescribed accordingly. Two new species, P. malagasyensis and P. persicus, each with 6 pectoral filaments, collected from the east coast of Africa, including Madagascar and the Persian Gulf, are
also described. Polydactylus sextarius and the 2 new species are characterized by 6 pectoral filaments. However, P. sextarius is distinguished from the latter by having lower gill raker counts (mode 28 vs. 31 in the latter) and an atrophied swimbladder
(vs. well-developed). Polydactylus malagasyensis differs from P. persicus in having higher pectoral fin ray counts (14 vs. mode 12 in the latter), the palatines inwardly turned anteriorly (vs. straight),
and a longer pectoral fin (mean 24% of standard length vs. 19%).
Received: February 5, 2001 / Revised: April 29, 2001 / Accepted: May 1, 2001 相似文献