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771.
Xinzhen Wang Ruiyong Jing Junjie Liu Zhenhua Yu Jian Jin Xiaobing Liu Xiaojuan Wang Guanghua Wang 《中国病毒学》2016,31(2):188-191
Electronic Supplementary MaterialSupplementary material is available for this article at 10.1007/s12250-015-3673-5 and is accessible for authorized users. 相似文献
772.
773.
How do environmental factors influence life cycles and development? An experimental framework for early‐diverging metazoans 下载免费PDF全文
Thomas C. G. Bosch Maja Adamska René Augustin Tomislav Domazet‐Loso Sylvain Foret Sebastian Fraune Noriko Funayama Juris Grasis Mayuko Hamada Masayuki Hatta Bert Hobmayer Kotoe Kawai Alexander Klimovich Michael Manuel Chuya Shinzato Uli Technau Seungshic Yum David J. Miller 《BioEssays : news and reviews in molecular, cellular and developmental biology》2014,36(12):1185-1194
774.
Exposure to contaminants below lethal concentrations may affect the performance of organisms, resulting in measurable differences in behavior. We measured the response of the benthic invertebrate Gammarus pulex (Crustacea, Amphipoda) to sublethal concentrations of three pharmaceuticals, fluoxetine, ibuprofen and carbamazepine, and the cationic surfactant cetyltrimethylammonium bromide (CTAB). Responses in behavior during exposure were analyzed using the multivariate method of Principal Response Curves (PRC). The PRC results show that exposure to low pharmaceutical concentrations (range 1–100 ng/l) resulted in increased ventilation, whereas exposure to control or to high concentrations (1 μ g/l–1 mg/L) resulted in increased locomotion. Exposure to CTAB resulted in decreased locomotion and increased ventilation at increasing concentrations. The results of our experiments indicate that increased ventilation can be used as a general sign of stress, but not necessarily an early warning signal for mortality. 相似文献
775.
The fluviatile Rhinogobius sp. 1 (hereinafter R. sp. 1) (Japanese name kibara-yoshinobori or English name yellow belly medium-egg type) is broadly distributed in the Ryukyu
Islands ranging from Amami-oshima Island to Iriomote Island. However, based on the molecular evidence, this species has probably
had multiple origins from amphidromous species. We compared the coloration of specimens at Amami-oshima I. with that of the
other specimens (islands) in the Ryukyu Is. Amami-oshima I. specimens of R. sp. 1 were different from the specimens of other populations in having five to six cross lines on the caudal fin. We examined
the early life history of fluviatile Rhinogobius at Amami-oshima I., based on rearing experiments, and estimated the age of wild specimens by counting otolith increments.
Spawned egg capsules of “Rhinogobius sp. 1” at Amami-oshima I. were larger than those of amphidromous species. Their developmental stage in newly hatched larvae
was similar to that of Okinawan R. sp. 1 in having a straight notochord; however, it had a flexed notochord earlier than that of Rhinogobius sp. 2 (hereinafter R. sp. 2) (aobara-yoshinobori or blue belly medium-egg type). The ontogenetic trajectory of “Rhinogobius sp. 1” in Amami-oshima I. was similar to Okinawan R. sp. 1 (30 days in larval duration) but different from R. sp. 2 (15 days). In amphidromous relatives of R. sp. 2, developmental timing during larval period was earlier than in the amphidromous relatives of R. sp. 1. It has been suggested that the phenomenon of fluvial landlocking has been accompanied somewhat by egg size increase
(on the basis of a few examples). However, the ontogenetic trajectories of fluviatile Rhinogobius species may be a reflection of those of ancestral amphidromous species.
Received: March 18, 2002 / Revised: November 7, 2002 / Accepted: December 10, 2002 相似文献
776.
777.
Edibility of fresh and decomposing macrophytes to three species of freshwater invertebrate herbivores 总被引:1,自引:1,他引:0
The edibility of two endemic Australian macrophytes (Ottelia ovalifolia and Triglochin procera) to three species of herbivorous stream invertebrates (Triplectides ciuskus and Notalina fulva: (Trichoptera: Leptoceridae) and Potamopyrgus niger (Gastropods: Hydrobiidae)) was investigated. Each macrophyte species was offered to the test animals in 5 different conditions: fresh, boiled, and three conditions of decomposition. In 5 out of 6 feeding trials, consumption rates of animals were greatest on decomposed tissues. Boiling increased edibility of both plant species to Triplectides larvae and of Triglochin to Notalina larvae. Boiled tissue was consumed least by Potamopyrgus. Analysis of nitrogen, phosphorus, and calorific content of macrophyte tissue and some terrestrial plant materials known to be eaten by the animals suggested that nutritional enrichment of decomposed and boiled tissues was unlikely to explain their greater edibility. Instead, the loss of anti-gustatory compounds is implicated. 相似文献
778.
The fluvial sculpin, Cottus
nozawae, is a coldwater-adapted fish distributed in Hokkaido Island and the northeastern part of Honshu Island (Tohoku District),
Japan. Mitochondrial DNA (mtDNA) control region sequencing was used to investigate the geographic distribution of genetic
variation and phylogeography of C. nozawae. Most populations possessed unique haplotypes, few being shared across river systems. Phylogenetic analysis of the sequences
of the mtDNA control region and adjacent regions of C. nozawae revealed three distinct phylogenetic groups that differed by 3.05% to 3.11%, corresponding to distinct geographic regions,
Hokkaido Island, northern Tohoku District, and Yamagata Prefecture (southwestern Tohoku District), respectively. The divergence
times of three groups were estimated to be about 1.5 million years ago by applying a general rate for mtDNA, suggesting that
the divergence among them might have occurred in the early Pleistocene. Divergence among the haplotypes within the group from
the northern Tohoku District was also high (1.84%), no haplotypes being shared by local populations in different river systems
in this region. Local populations from a single river system in this region comprise a distinct lineage that differed from
other river systems. Such genetically divergent population structures among the different regions and river systems are considered
to have resulted mainly from long-term isolation and restricted gene flow among river systems, probably promoted by the fluvial
benthic life history and low dispersal ability of this species.
Received: April 12, 2001 / Revised: December 1, 2001 / Accepted: December 19, 2001 相似文献
779.
Danielle Defaye 《Hydrobiologia》1995,310(1):11-18
Four species of the genusMesocyclops (Cyclopoida: Cyclopidae) are reported from Israel:Mesocyclops kieferi Van de Velde, 1984,Mesocyclops aequatorialis similis Van de Velde, 1984,Mesocyclops ogunnus Onabamiro, 1957 andMesocyclops arcanus n.sp. The new species, close toM. kieferi, is described and some remarks are given for the other species. 相似文献
780.
The taxonomic distribution, structure, and biological activity of halogenated alkaloids isolated from marine microorganisms and sponges are reviewed. The structures of nearly 140 natural bromo- and iodo-containing alkaloids are shown. 相似文献