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71.
72.
Denise Navia Ronald Ochoa Cal Welbourn Francisco Ferragut 《Experimental & applied acarology》2010,51(1-3):225-255
Eriophyoids have high potential as adventive mite species (AMS) because their small size make them difficult to detect, and can be easily distributed in world trade. Economic, social and environmental impact from adventive eriophyoid mites has been significant. Considerable attention has been given to adventive insect species while adventive mites have received little attention and little information is available for eriophyoids. This paper summarizes information on adventive eriophyoid mites, their impact, and the history of some important invasions. The status of adventive species of eriophyoids introduced as biological control agents of weeds is presented. A list of eriophyoid mites reported as invasive species worldwide is given. Pathways of concern and biosecurity actions to reduce the risk of eriophyoid mites are discussed. The need to raise public awareness of the risk and importance of these tiny organisms as AMS is emphasized. Scientific and technical challenges to deal with adventive eriophyoids are discussed. 相似文献
73.
Massimo Scandura Laura Iacolina Marco Apollonio Francesco Dessì-Fulgheri Mariella Baratti 《European Journal of Wildlife Research》2010,56(1):33-42
Four Alectoris species inhabit the Mediterranean area, where they represent important gamebirds subject to human manipulations. The Sardinian
partridge is peculiar in Europe, in that it belongs to the African species Alectoris barbara. Nevertheless, no comprehensive study has as yet investigated its genetic status as regards both the extant levels of genetic
diversity and the possible contamination due to introgressive hybridization with other Mediterranean species. For the purposes
of this study, we analyzed 65 samples of Sardinian partridges, 40 of which came from the wild population and 25 from captive
stocks. No one of them showed a mtDNA polymerase chain reaction restriction fragment length polymorphism haplotype assigned
to another species than A. barbara, thus, ruling out a possible introgression in the maternal line. In addition, we compared these samples with 94 partridges
from other circum-Mediterranean populations using a set of eight chicken (Gallus gallus) microsatellites. A low level of genetic variation was observed in the Sardinian population (H
E = 0.310; k
AR = 2.69), comparable only to that observed in the Sicilian rock partridge (A. graeca). The comparison with the Tunisian population showed that its present genetic composition is consistent with a historical
introduction from North Africa, showing possible effects of a post-introductional genetic drift. Bayesian tests assigned all
but one individuals with >90% probability to A. barbara, thus, providing evidence that no or only a few exotic Alectoris genes have introgressed into Sardinian partridges. 相似文献
74.
75.
Mitochondrial DNA and the peopling of South America 总被引:1,自引:0,他引:1
Lewis CM Lizárraga B Tito RY López PW Iannacone GC Medina A Martínez R Polo SI De La Cruz AF Cáceres AM Stone AC 《Human biology; an international record of research》2007,79(2):159-178
The initial peopling of South America is largely unresolved, in part because of the unique distribution of genetic diversity in native South Americans. On average, genetic diversity estimated within Andean populations is higher than that estimated within Amazonian populations. Yet there is less genetic differentiation estimated among Andean populations than estimated among Amazonian populations. One hypothesis is that this pattern is a product of independent migrations of genetically differentiated people into South America. A competing hypothesis is that there was a single migration followed by regional isolation. In this study we address these hypotheses using mtDNA hypervariable region 1 sequences representing 21 South American groups and include new data sets for four native Peruvian communities from Tupe, Yungay, and Puno. An analysis of variance that compared the combined data from western South America to the combined data from eastern South America determined that these two regional data sets are not significantly different. As a result, a migration from a single source population into South America serves as the simplest explanation of the data. 相似文献
76.
Leandro Finkler Christine Lamenha Luna-Finkler José Carlos Pinto Tito Livio Moitinho Alves 《World journal of microbiology & biotechnology》2007,23(12):1789-1795
Separation and cells concentration constitute important stages in most biotechnological processes. Particularly, use of flocculation/sedimentation
can improve significantly the extraction of biopolymers accumulated by microorganisms and the biodegradation of xenobiotic
compounds by cell sludge. In this work the use of tannin and aluminum sulphate (Al2(SO4)3) as flocculating agents for concentration of cells of Cupriavidus necator DSM 545 is evaluated. Cells were grown in broth nutrient medium in Erlenmeyer flasks, submitted to orbital agitation of 160 rpm
at 30 °C for 21 h. The optimal concentrations of flocculating agents, as determined with a standard jar test method, were
equal to 2,800 mg/L for tannin and 800 mg/L for Al2(SO4)3, allowing for recovery of 95% of the cells in both cases. Obtained flocs presented density and average diameter of 1.03 g/mL ± 0.01 g/mL
and 158 μm ± 19 μm for tannin and of 1.05 g/mL ± 0.01 g/mL and 146 μm ± 14 μm for Al2(SO4)3, respectively. Batch settling tests were performed in order to determine the operational capacity of continuous settlers
to be used for separation of the investigated flocculent suspensions. Finally, cultivation of cells using flocs as inoculum
indicated that the cells remained viable after flocculation with usage of the optimum flocculating agent concentrations. 相似文献
77.
Nicolì Marco Riehl Simone Webster Lyndelle Streit Katharina Höflmayer Felix 《Vegetation History and Archaeobotany》2022,31(6):559-577
Vegetation History and Archaeobotany - In this paper, we present the results of the plant macrofossil analyses from the site of Tel Lachish, Israel with focus on the botanical assemblage of the... 相似文献
78.
Bice Avallone Claudio Agnisola Raimondo Cerciello Raffaele Panzuto Palma Simoniello Patrizia Cretì Chiara Maria Motta 《Cell biology and toxicology》2015,31(6):273-283
This report describes the alterations induced by an environmentally realistic concentration of cadmium in skeletal muscle fibre organization, composition, and function in the teleost zebrafish. Results demonstrate that the ion induces a significant quantitative and qualitative deterioration, disrupting sarcomeric pattern and altering glycoprotein composition. These events, together with a mitochondrial damage, result in a significant reduction in swimming performance. In conclusion, the evidence here collected indicate that in presence of an environmental cadmium contamination, important economic (yields in fisheries/aquaculture), consumer health (fish is an important source of proteins), and ecological (reduced fitness due to reduced swimming performance) consequences can be expected. 相似文献
79.
T. Cobo A. Obaya S. Cal L. Solares R. Cabo J.A. Vega J. Cobo 《European journal of histochemistry : EJH》2015,59(3)
The periostin is a matricellular protein expressed in collagen-rich tissues including some dental and periodontal tissues where it is regulated by mechanical forces, growth factors and cytokines. Interestingly the expression of this protein has been found modified in different gingival pathologies although the expression of periostin in normal human gingiva was never investigated. Here we used Western blot and double immunofluorescence coupled to laser-confocal microscopy to investigated the occurrence and distribution of periostin in different segments of the human gingival in healthy subjects. By Western blot a protein band with an estimated molecular mass of 94 kDa was observed. Periostin was localized at the epithelial-connective tissue junction, or among the fibers of the periodontal ligament, and never co-localized with cytokeratin or vimentin thus suggesting it is an extracellular protein. These results demonstrate the occurrence of periostin in adult human gingiva; its localization suggests a role in the bidirectional interactions between the connective tissue and the epithelial cells, and therefore in the physiopathological conditions in which these interactions are altered.Key words: Periostin, matricellular proteins, human gingiva 相似文献
80.
Giuseppina Apicella Debora Beldì Giansilvio Marchioro Sara Torrente Sara Tunesi Corrado Magnani Alessandro Volpe Carlo Terrone Marco Krengli 《Reports of Practical Oncology and Radiotherapy》2015,20(2):113-122