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91.
Tserendorj Gegeensuvd Marinova Elena Lechterbeck Jutta Behling Hermann Wick Lucia Fischer Elske Sillmann Marion Märkle Tanja Rösch Manfred 《Vegetation History and Archaeobotany》2021,30(1):35-46
Vegetation History and Archaeobotany - A system of farming with an alternation of land use between being cultivated or left fallow as grassland (Feldgraswirtschaft) developed in southwestern... 相似文献
92.
Federica Villa Lucia Giacomucci Andrea Polo Pamela Principi Lucia Toniolo Marienella Levi Stefano Turri Francesca Cappitelli 《Biotechnology letters》2009,31(9):1407-1413
The potential on N-vanillylnonanamide (NVN) in preventing the attachment of Pseudomonas stutzeri and a Bacillus cereus-group strain was investigated. NVN up to 852 μM was not toxic, nor was it an energy source for either organism. Microbial
attachment assays were carried out on glass and polylysine slides. with NVN being dispersed in or applied to the surfaces
using a polyurethane coating. NVN at 205 μM inhibited Bacillus adhesion on glass slides by 48% and the percentage did not significantly increase at 852 μM. NVN blended into or sprayed
onto the coating at 205 μmol/kg did not prevent adhesion. The compound is therefore not useful as an antifouling product under
the tested coating conditions. 相似文献
93.
Martine Batoux Milena Roux Alejandra Rougon Pascal Bittel Marta Kiss‐Papp Delphine Chinchilla H Peter van Esse Lucia Jorda Benjamin Schwessinger Valerie Nicaise Bart P H J Thomma Antonio Molina Jonathan D G Jones Cyril Zipfel 《The EMBO journal》2009,28(21):3428-3438
In plant innate immunity, the surface‐exposed leucine‐rich repeat receptor kinases EFR and FLS2 mediate recognition of the bacterial pathogen‐associated molecular patterns EF‐Tu and flagellin, respectively. We identified the Arabidopsis stromal‐derived factor‐2 (SDF2) as being required for EFR function, and to a lesser extent FLS2 function. SDF2 resides in an endoplasmic reticulum (ER) protein complex with the Hsp40 ERdj3B and the Hsp70 BiP, which are components of the ER‐quality control (ER‐QC). Loss of SDF2 results in ER retention and degradation of EFR. The differential requirement for ER‐QC components by EFR and FLS2 could be linked to N‐glycosylation mediated by STT3a, a catalytic subunit of the oligosaccharyltransferase complex involved in co‐translational N‐glycosylation. Our results show that the plasma membrane EFR requires the ER complex SDF2–ERdj3B–BiP for its proper accumulation, and provide a demonstration of a physiological requirement for ER‐QC in transmembrane receptor function in plants. They also provide an unexpected differential requirement for ER‐QC and N‐glycosylation components by two closely related receptors. 相似文献
94.
Sex differences in spatial learning are found in many species of mammals and even in invertebrates. Results from laboratory mouse studies, however, have been inconsistent in comparison to studies of humans, laboratory rats and wild rodent species. Here we re-examined this question in C57BL/6J mice that were exposed to enriched environments using two tasks, an object recognition task and a place learning task where mice were motivated by exploratory drive, not aversive conditioning or food restriction. Using these methods, we found a female advantage for object recognition, similar to the female advantage found in humans and laboratory rats. In the place learning task, male performance was unimpaired by intra-maze cue deletion but impaired by extra-maze cue masking. Female mice, in contrast, were able to navigate accurately under both cue conditions. In summary, by utilizing testing and housing methods that were more species appropriate, we found sex-specific patterns of cue encoding and place learning in better accordance with prior results from other mammalian species. The implication of these results is that the C57BL/6J mouse is an appropriate model for the study of cognitive sex differences in mammals. 相似文献
95.
A.S. Varela Junior C.D. Corcini R.R. Ulguim M.V.F. Alvarenga I. Bianchi M.N. Corrêa T. Lucia Jr. J.C. Deschamps 《Animal reproduction science》2009,115(1-4):323-327
Egg yolk is included in extenders for semen cryopreservation due to its protective effect against cold shock, which is attributed to the presence of low density lipoprotein (LDL). This study evaluates how semen quality is affected by using LDL as a replacement for egg yolk in extenders for cooled and frozen dog semen. In Experiment 1, semen was extended in TRIS–glucose at 5 °C, in four treatments: 20% egg yolk (T1); 6% (T2); 8% (T3); and 10% LDL (T4). Sperm motility and membrane integrity after 24, 48, 72 and 96 h and the 50% conservation rate of motile spermatozoa (50 M) were evaluated. The 50 M was less for T1 than for the other treatments (P < 0.01), but T2–T4 did not differ (P > 0.05). In Experiment 2, glycerol at 10% was included in the freezing extender, in treatments similar to those from Experiment 1. Sperm motility and membrane integrity did not differ for T2, T3 and T4 at any period in Experiment 1 and after thawing in Experiment 2 (P > 0.05), but were greater for all LDL treatments than for T1 (P < 0.01), in both experiments. Thus, LDL can replace egg yolk in the composition of the TRIS–glucose extender for cooled or frozen dog semen. 相似文献
96.
Magali Lucia Jean-Marc Andre Patrice Gonzalez Magalie Baudrimont Karine Gontier Regine Maury-Brachet Stephane Davail 《Biometals》2009,22(5):843-853
The impact on palmiped Cairina moschata of two levels of dietary cadmium (Cd) contamination (C1: 1 mg kg−1 and C10: 10 mg kg−1) was investigated on liver gene expression by real-time PCR. Genes involved in mitochondrial metabolism, in antioxidant defences,
detoxification and in DNA damage repair were studied. Metallothionein (MT) protein levels and Cd bioaccumulation were also
investigated in liver, kidneys and muscle. Male ducks were subjected to three periods of exposure: 10, 20 and 40 days. Cd
was mainly bioaccumulated in kidneys first and in liver. The concentrations in liver and kidneys appeared to reach a stable
level at 20 days of contamination even if the concentrations in muscle still increased. Cd triggered the enhancement of mitochondrial
metabolism, the establishment of antioxidant defences (superoxide dismutase Mn and Cu/Zn; catalase) and of DNA repair from
20 days of contamination. Discrepancies were observed in liver between MT protein levels and MT gene up-regulation. MT gene
expression appeared to be a late hour biomarker. 相似文献
97.
98.
Enrique Samper Lucia Morgado Juan C. Estrada Antonio Bernad Alan Hubbard Susana Cadenas Simon Melov 《Free radical biology & medicine》2009,46(3):387-396
Lymphomas adapt to their environment by undergoing a complex series of biochemical changes that are currently not well understood. To better define these changes, we examined the gene expression and gene ontology profiles of thymic lymphomas from a commonly used model of carcinogenesis, the p53?/? mouse. These tumors show a highly significant upregulation of mitochondrial biogenesis, mitochondrial protein translation, mtDNA copy number, reactive oxygen species, antioxidant defenses, proton transport, ATP synthesis, hypoxia response, and glycolysis, indicating a fundamental change in the bioenergetic profile of the transformed T cell. Our results suggest that T cell tumorigenesis involves a simultaneous upregulation of mitochondrial biogenesis, mitochondrial respiration, and glycolytic activity. These processes would allow cells to adapt to the stressful tumor environment by facilitating energy production and thereby promote tumor growth. Understanding these adaptations is likely to result in improved therapeutic strategies for this tumor type. 相似文献
99.
Giovanni Gherardi Lucia De Florio Giulia Lorino Laura Fico & Giordano Dicuonzo 《FEMS immunology and medical microbiology》2009,55(1):62-67
One hundred macrolide-resistant staphylococcal isolates from clinically relevant infections in Italy during a 19-month period were studied. Four distinct resistance phenotypes were observed using the triple-disk induction test (erythromycin, clindamycin, telithromycin): the cMLSB phenotype (24 isolates); the iMLSB phenotype (41 isolates); the MS phenotype (three isolates); and the iMTS phenotype (erythromycin-induced telithromycin resistance) (32 isolates). ermC and ermA genes predominated within erythromycin-resistant Staphylococcus aureus isolates with iMLSB phenotype and cMLSB phenotype, respectively. Among erythromycin-resistant CoNS isolates, half of the strains showed the iMTS or MS/ msrA association, and ermC gene predominated among isolates with MLSB phenotype. By pulsed-field gel electrophoresis, high genetic heterogeneity was observed among the isolates studied. Both independent acquisition of macrolide resistance genes and spread of specific resistant clones were observed. Association between certain clonal types and specific types of infection could be detected. To our knowledge, this is the first report on characterization of erythromycin-resistant staphylococci in Italy. 相似文献
100.
Lucia Rigamonti Mario Grosso Maria Caterina Sunseri 《The International Journal of Life Cycle Assessment》2009,14(5):411-419
Background, aim, and scope Life cycle assessment (LCA) applied to alternative waste management strategies is becoming a commonly utilised tool for decision
makers. This LCA study analyses together material and energy recovery within integrated municipal solid waste (MSW) management
systems, i.e. the recovery of materials separated with the source-separated collection of MSW and the energy recovery from
the residual waste. The final aim is to assess the energetic and environmental performance of the entire MSW management system
and, in particular, to evaluate the influence of different assumptions about recycling on the LCA results.
Materials and methods The analysis uses the method of LCA and, thus, takes into account that any recycling activity influences the environment not
only by consuming resources and releasing emissions and waste streams but also by replacing conventional products from primary
production. Different assumptions about the selection efficiencies of the collected materials and about the quantity of virgin
material substituted by the reprocessed material were made. Moreover, the analysis considers that the energy recovered from
the residual waste displaces the same quantity of energy produced in conventional power plants and boilers fuelled with fossil
fuels.
Results The analysis shows, in the expanded model of the material and energy recovering chain, that the environmental gains are higher
than the environmental impacts. However, when we reduce the selection efficiencies by 15%, the impact indicators worsen by
a percentage included between 10% and 26%. This phenomenon is even more evident when we consider a substitution ratio of 1:<1
for paper and plastic: The worsening is around 15–20% for all the impact indicators except for the global warming for which
the worsening is up to 45%.
Discussion Hypotheses about the selection efficiencies of the source-separated collected materials and about the substitution ratio have
a great influence on the LCA results. Consequently, policy makers have to be aware of the fact that the impacts of an integrated
MSW management system are highly dependent on the assumptions made in the modelling of the material recovery, as well as in
the modelling of the energy recovery.
Conclusions LCA allows to evaluate the impacts of integrated systems and how these impacts change when the assumptions made during the
modelling of the different single parts of the system are modified. Due to the significant impacts that hypotheses about material
recovery have in the results, they should be expressed in a very transparent way in the report of LCA studies, together with
the assumptions made about energy recovery.
Recommendations and perspectives The results suggest that the hypotheses about the value of the substitution ratio are very important, and the case of wood
should therefore be better analysed and a substitution ratio of 1:<1 should be used, as for paper and plastic. It seems that
the assumptions made about which material is replaced by the recycled one are very important too, and in this sense, more
research is needed about what the recycled plastic may effectively substitute, in particular the polyolefin mix. 相似文献