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991.
《Animal : an international journal of animal bioscience》2018,12(12):2551-2560
Subacute ruminal acidosis (SARA) is a prevalent metabolic disorder in dairy cows known to elicit local and systemic immune responses. We recently showed that cows experiencing SARA and challenged intramammarily with lipopolysaccharide (LPS) experienced stronger metabolic disturbances compared with cows without SARA. Therefore, we hypothesized that cows experiencing SARA have a modulated innate immune response and impaired plasma metabolome compared with healthy cows when experiencing an acute mastitis challenge. A total of 18 Simmental cows were subjected either to a Control (CON, n=6) or SARA (n=12) feeding regimen, receiving either 40% or 60% concentrates for 30 days. Thereafter, six SARA (SARA-LPS) and the CON (CON-LPS) cows were intramammarily challenged with 50 µg LPS from Escherichia coli (O26 : B6), while the remaining six SARA cows (SARA-PLA) received a placebo. Blood and milk samples were analyzed for acute phase proteins and a targeted ESI-LC-MS/MS-based metabolomics approach was performed in blood samples 24 h after the LPS challenge. The LPS infusion caused a strong increase in immune response variables, with a higher concentration of milk amyloid A 48 h after the LPS challenge in SARA-LPS compared with CON-LPS cows. Cows receiving the LPS infusion had a lower plasma concentration of several amino acids and lysophosphatidylcholines but without differences in SARA cows and healthy cows. In conclusion, our results revealed that an intramammary LPS infusion increased acute phase proteins and modulated the blood metabolome. While no systemic differences between SARA and healthy cows were observed, cows experiencing SARA showed a higher concentration of an acute phase protein at the local level of the mammary gland. Further research is required to elucidate the underlying mechanisms and to evaluate its clinical significance for udder health. 相似文献
992.
Response of maize stemborers and associated parasitoids to the spread of grasses in the rainforest zone of Kisangani,DR Congo: effect on stemborers biological control 下载免费PDF全文
Onésime M. Kankonda Benjamin D. Akaibe Ntambo M. Sylvain Bruno‐Pierre Le Ru 《Agricultural and Forest Entomology》2018,20(2):150-161
993.
Construction of a multicontrol sterility system for a maize male‐sterile line and hybrid seed production based on the ZmMs7 gene encoding a PHD‐finger transcription factor 下载免费PDF全文
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997.
Oxylipins from both pathogen and host antagonize jasmonic acid‐mediated defence via the 9‐lipoxygenase pathway in Fusarium verticillioides infection of maize 下载免费PDF全文
Paola Battilani Alessandra Lanubile Valeria Scala Massimo Reverberi Rossella Gregori Claudia Falavigna Chiara Dall'asta Yong‐Soon Park John Bennett Eli J. Borrego Michael V. Kolomiets 《Molecular Plant Pathology》2018,19(9):2162-2176
Oxylipins are a newly emerging group of signals that serve defence roles or promote virulence. To identify specific host and fungal genes and oxylipins governing the interactions between maize and Fusarium verticillioides, maize wild‐type and lipoxygenase3 (lox3) mutant were inoculated with either F. verticillioides wild‐type or linoleate‐diol‐synthase 1‐deleted mutant (ΔFvlds1D). The results showed that lox3 mutants were more resistant to F. verticillioides. The reduced colonization on lox3 was associated with reduced fumonisin production and with a stronger and earlier induction of ZmLOX4, ZmLOX5 and ZmLOX12. In addition to the reported defence function of ZmLOX12, we showed that lox4 and lox5 mutants were more susceptible to F. verticillioides and possessed decreased jasmonate levels during infection, suggesting that these genes are essential for jasmonic acid (JA)‐mediated defence. Oxylipin profiling revealed a dramatic reduction in fungal linoleate diol synthase 1 (LDS1)‐derived oxylipins, especially 8‐HpODE (8‐hydroperoxyoctadecenoic acid), in infected lox3 kernels, indicating the importance of this molecule in virulence. Collectively, we make the following conclusions: (1) LOX3 is a major susceptibility factor induced by fungal LDS1‐derived oxylipins to suppress JA‐stimulating 9‐LOXs; (2) LOX3‐mediated signalling promotes the biosynthesis of virulence‐promoting oxylipins in the fungus; and (3) both fungal LDS1‐ and host LOX3‐produced oxylipins are essential for the normal infection and colonization processes of maize seed by F. verticillioides. 相似文献
998.
Pedro H. Mainardi Valker A. Feitosa Livia B. Brenelli de Paiva Rafaella C. Bonugli-Santos Fabio M. Squina Adalberto Pessoa Lara D. Sette 《Fungal biology》2018,122(5):302-309
Laccase production in saline conditions is still poorly studied. The aim of the present study was to investigate the production of laccase in two different types of bioreactors by the marine-derived basidiomycete Peniophora sp. CBMAI 1063. The highest laccase activity and productivity were obtained in the Stirred Tank (ST) bioreactor, while the highest biomass concentration in Air-lift (AL) bioreactor. The main laccase produced was purified by ion exchange and size exclusion chromatography and appeared to be monomeric with molecular weight of approximately 55 kDa. The optimum oxidation activity was obtained at pH 5.0. The thermal stability of the enzyme ranged from 30 to 50 °C (120 min). The Far-UV Circular Dichroism revealed the presence of high β-sheet and low α-helical conformation in the protein structure. Additional experiments carried out in flask scale showed that the marine-derived fungus was able to produce laccase only in the presence of artificial seawater and copper sulfate. Results from the present study confirmed the fungal adaptation to marine conditions and its potential for being used in saline environments and/or processes. 相似文献
999.
Projects funded by International Development Research Centre (IDRC) of Canada and the European Commission have enabled the
examination of more than 3000 samples of maize collected from all regions of Costa Rica at different stages, from the growing
crop through storage to final sale, and at different water contents. Contamination with Aspergillus flavus was frequent and
about 80% of samples contained more than 20 ng aflatoxins g-1 grain. Average contamination with aflatoxins in the Brunca Region
was > 274 ng g -1 while that in other regions was < 70 ng g -1. Except in Brunca region, where it averaged 376 ng g -1, contamination
of grain from commercial sources was slightly less than of that from farms (≤15 ng g-1). It appeared that samples kept on
the cob after harvest contained almost no aflatoxin while shelled samples were frequently highly contaminated. Experiments
were therefore done in Brunca and Huetar Atlantic Regions, utilising 34 experimental maize crops to study in detail the development
of A. flavus and aflatoxin from before harvest, through postharvest treatment before drying and through storage for six months.
A. flavus was isolated more frequently from maize shelled immediately after harvest than from that kept on the cob until it
could be dried, and from more samples from the Brunca Region than from the Huetar Atlantic Region. Samples harvested with
≥18% water content often contained >70% of grains infected with A. flavus but sometimes there were few grains infected. As
found in the initial survey, more aflatoxin contamination developed in shelled maize than in that handled on the cob during
the period from harvesting to drying, especially if the delay was more than 5 days, and more in Brunca than in Huetar. Shelled
grain contained 400–800 ng aflatoxin g -1 in Brunca but <100 ng g-1 in Huetar while grain kept on the cob contained <30 ng
g-1, even with >18% water content. Incidence of Fusarium spp. exceeded 50% except where A. flavus colonized more than 80%
of grains.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
1000.
The formation of conidia in Phaeocytostroma ambiguum on different media and conditions was investigated in this study. Carnation
leaf agar (CLA) and a 12 h photoperiod (24/18 °C) provided excellent conditions for the promotion of rapid formation of both
alpha (α) and beta (β) conidia in a number of P. ambiguum isolates. The dimensions of α- and β-conidia amounted to 6.0–19.6
× 3.8–7.5 μm and 6.0–24.9 × 1.1–2.6 μm, respectively. They were produced on short or elongate, simple and branched conidiophores.
β-conidia have not been described before in P. ambiguum. Intermediate conidia were rarely found.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献