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341.
WIM R. WILLEMS TOM J. ARTOIS WOUTER A. VERMIN ERNEST R. SCHOCKAERT 《Zoological Journal of the Linnean Society》2004,141(2):271-296
A morphological and taxonomic account of the genus Trigonostomum is provided. All known species are discussed and briefly re-described where necessary. Seven new species are described: T. franki from Curaçao, Florida (USA), the East African Coast and New Caledonia, T. nataschae from the French sub-Antarctic island Kerguelen, T. spinigerum from New Caledonia and T. watsoni from the Australian East Coast and New Caledonia. T. tori and T. galapagoensis , both formerly enclosed in T. setigerum , are considered new species, while T. australis also belongs to the same species group. Proxenetes denhartogi is transferred to Trigonostomum . Based on a comparison of old and new material, T. marki is synonymized with T. penicillatum , while T. prytherchi and T. divae are regarded as junior synonyms of T. lilliei ; T. intermedium and T. quadrifolium are considered synonyms of T. coronatum . Three species are considered species inquirendae : T. brunchorsti , T. piriforme and Marinellia lingulifera . Similarities and differences of the 17 valid species are discussed and summarized in an identification key. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 271–296. 相似文献
342.
“微生物学”是生物科学类各专业的专业基础课,同时也是一门实践性和科研性很强的学科,学科理论的发展与生物技术的革新是互相促进、相辅相成的。在科学技术高速发展,科研成就层出不穷的今天,“微生物学”教学内容必须与时俱进,紧跟学科发展步伐,体现出学科前沿探究的最新成果。本文以放线菌的认知及其分类地位的演变为例,阐述“微生物学”课程中放线菌篇章的内容革新,旨在促进更加合理的“微生物学”课程教学体系的建设,以期提高教学水平,为高质量培养生物科学类专业技术人才奠定基础。 相似文献
343.
R Caputto A H Maccioni B L Caputto 《Biochemical and biophysical research communications》1977,74(3):1046-1052
ATPase was prepared from brain microsomes by solubilization with sodium deoxycholate and fractionated at different concentrations of ammonium sulfate. The Mg2+-ATPase was activated by total brain gangliosides, disialoganglioside, monosialo — ganglioside, hematoside, total brain gangliosides obtained from a patient with Tay-Sachs disease and asialoganglioside. The effect was smaller on Ca2+-ATPase and negligible on (Na+ + K+)-ATPase. Lactosyl-ceramide, glucosyl-ceramide, galactosyl-ceramide, ceramide and sialyl-lactose failed to produce activation. 相似文献
344.
345.
Recent Advances in Our Knowledge of the Myxozoa 总被引:20,自引:0,他引:20
MICHAEL L. KENT KARL B. ANDREE JERRI L. BARTHOLOMEW MANSOUR EL-MATBOULI SHERWIN S. DESSER ROBERT H. DEVLIN STEPHEN W. FEIST RONALD P. HEDRICK RUDOLF W. HOFFMANN JASWINDER KHATTRA SASCHA L. HALLETT ROBERT J. G. LESTER MATTHEW LONGSHAW OSWALDO PALENZEULA MARK E. SIDDALL CHONGXIE XIAO 《The Journal of eukaryotic microbiology》2001,48(4):395-413
In the last few years two factors have helped to significantly advance our understanding of the Myxozoa. First, the phenomenal increase in fin fish aquaculture in the 1990s has lead to the increased importance of these parasites; in turn this has lead to intensified research efforts, which have increased knowledge of the development, diagnosis. and pathogenesis of myxozoans. The hallmark discovery in the 1980s that the life cycle of Myxobolus cerebralis requires development of an actinosporean stage in the oligochaete. Tubifex tubifex, led to the elucidation of the life cycles of several other myxozoans. Also, the life cycle and taxonomy of the enigmatic PKX myxozoan has been resolved: it is the alternate stage of the unusual myxozoan, Tetracapsula bryosalmonae, from bryozoans. The 18S rDNA gene of many species has been sequenced, and here we add 22 new sequences to the data set. Phylogenetic analyses using all these sequences indicate that: 1) the Myxozoa are closely related to Cnidaria (also supported by morphological data); 2) marine taxa at the genus level branch separately from genera that usually infect freshwater fishes; 3) taxa cluster more by development and tissue location than by spore morphology; 4) the tetracapsulids branched off early in myxozoan evolution, perhaps reflected by their having bryozoan, rather than annelid hosts; 5) the morphology of actinosporeans offers little information for determining their myxosporean counterparts (assuming that they exist); and 6) the marine actinosporeans from Australia appear to form a clade within the platysporinid myxosporeans. Ribosomal DNA sequences have also enabled development of diagnostic tests for myxozoans. PCR and in situ hybridisation tests based on rDNA sequences have been developed for Myxobolus cerebralis, Ceratomyxa shasta, Kudoa spp., and Tetracapsula bryosalmonae (PKX). Lectin-based and antibody tests have also been developed for certain myxozoans, such as PKX and C. shasta. We also review important diseases caused by myxozoans, which are emerging or re-emerging. Epizootics of whirling disease in wild rainbow trout (Oncorhynchus mykiss) have recently been reported throughout the Rocky Mountain states of the USA. With a dramatic increase in aquaculture of fishes using marine netpens, several marine myxozoans have been recognized or elevated in status as pathological agents. Kudoa thyrsites infections have caused severe post-harvest myoliquefaction in pen-reared Atlantic salmon (Salmo salar), and Ceratomyxa spp., Sphaerospora spp., and Myxidium leei cause disease in pen-reared sea bass (Dicentrarchus labrax) and sea bream species (family Sparidae) in Mediterranean countries. 相似文献
346.
JANA LEONG-KORNIKOVÁ OTAKAR ÍDA SIRIL WIJESUNDARA KAROL MARHOLD 《Botanical journal of the Linnean Society. Linnean Society of London》2008,157(1):37-46
Although Curcuma L. (Zingiberaceae) is a conserved name, with C. longa L. as its conserved type, the type of C. longa is still uncertain. Numerous discussions about the identity of the taxon called C. longa by Linnaeus have been followed by various attempts to rename turmeric, suggestions as how to settle the type and proposals to conserve the name from a later author in order to stabilize the situation. Unfortunately, none of the previous proposals can be upheld for reasons which are discussed in this article. A lectotype is selected from extant material examined by Linnaeus and an epitype collected near the type locality is designated here. The identity of C. longa is discussed and a colour plate of the species is included. Synonyms of C. longa and their types are discussed and notes on the variability of C. longa are provided. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 37–46. 相似文献
347.
PHILIP S. L. ANDERSON 《Biological journal of the Linnean Society. Linnean Society of London》2008,94(1):195-216
Imprecise usage of terminology can lead to confusion when trying to compare cranial musculature between taxa from different higher-order groups. The present study aimed to present hypotheses of muscle homology between taxa from four modern gnathostome groups: Actinopterygii ( Amia calva ), Sarcopterygii ( Latimeria chalumnae ), Elasmobranchii ( Squalus acanthias , Chlamydoselachus anguineus ), and Holocephali ( Hydrolagus colliei ). Muscle homologies are hypothesized based on topological data taken from the anatomical literature and supplemented by new observations of Hydrolagus colliei . Hypothesized muscle groups are tested for congruence against accepted gnathostome phylogeny. From these data, eight muscle groups are identified that are unambiguously homologous across all taxa examined. Four more muscle groups are found to be homologous across a majority of the taxa. Twelve muscle groups are hypothesized to be basal across all gnathostomes. A muscle in Hydrolagus previously called both a geniohyoideus and interhyoideus is here renamed 'mandibulohyoideus' to reflect its apomorphic condition. The presence of coracomandibular muscles in all groups supports the hypothesis that basal jaw depression systems in gnathostomes were not linked to hyoid movement, but independently operated by this muscle. The study also offers new insight into muscle reconstruction in fossil groups (Placodermi). © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 195–216. 相似文献
348.
Summary Due to an oversight, the name Philodendron millerianum, was not validly published in a recent paper by Coelho & Sakuragui (2007). This error is corrected here and the location of the holotype and isotype confirmed. 相似文献
349.
Malte C. Ebach Juan J. Morrone Lynne R. Parenti Ángel L. Viloria 《Journal of Biogeography》2008,35(7):1153-1157
Biogeography needs a standard, coherent nomenclature. Currently, in biogeography, the same name is used for different areas of biological endemism, and one area of endemism is known by more than one name, which leads to conflict and confusion. The name 'Mediterranean', for example, may mean different things to different people – all or part of the sea, or the land in and around it. This results in ambiguity concerning the meaning of names and, more importantly, may lead to conflicts between inferences based on different aspects of a given name. We propose the International Code of Area Nomenclature (ICAN), a naming system that can be used to classify newly coined or existing names based on a standard. When fully implemented, the ICAN will improve communication among biogeographers, systematists, ecologists and conservation biologists. 相似文献
350.
线粒体DNA(mtDNA)多态性在动物保护生物学中的应用 总被引:10,自引:1,他引:9
本文从两个方面论述了mtDNA在动物保护生物学中的应用:一是对物种进行遗传多样性的检 测与管理,二是进行与种群统计学数据相关的遗传分析。前者与保护的长期效益(如进化) 密切相关,而后者则主要用于指导短期管理措施的制定。同时,本文重点论述了mtDNA在进 化显著单位(ESUs)和管理单位(MUs)的认定方面的作用。认定ESUs的目的是隔离管理遗传多 样性,它是一系列系统进化史独特的种群,这种独特性同时表现在mtDNA和核DNA上;MUs是 种群统计意义上的生殖隔离单位,具有独特的等位基因频率,与系统发生结构和遗传分歧水 平无关。ESUs与MUs都是保护生物学中保护与管理的重要基本单位。 相似文献