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41.
42.
Supercritical carbon dioxide fractionation of nonesterified alkoxyglycerols obtained from shark liver oil 总被引:1,自引:0,他引:1
Vázquez L Fornari T Señoráns FJ Reglero G Torres CF 《Journal of agricultural and food chemistry》2008,56(3):1078-1083
Ethanolysis of shark liver oil was carried out to generate a product enriched in nonesterified alkoxyglycerols and fatty acid ethyl esters. For the present study, the original oil contained very low amounts of squalene, and thus, unsaponifiable matter was mainly constituted by nonesterified alkoxyglycerols (NEAKG). A small percentage of monoesterified alkoxyglycerols (MEAKG) was also detected. Supercritical fluid extraction was employed to fractionate the mixture, achieving a complete elimination of esters and concentrating the alkoxyglycerol compounds in the raffinate product. Extractions were carried out in a countercurrent packed column, using extraction pressures in the range of 140-180 bar, temperatures from 45 to 65 degrees C, and a solvent-to-feed ratio of 15. NEAKG + MEAKG purity obtained in the raffinate at the best extraction conditions was around 78% w/w, and satisfactory yield (>60%) was also achieved. Therefore, the raffinate product can be re-esterified to design highly valuable ether lipid compounds. 相似文献
43.
Diano N Grimaldi T Bianco M Rossi S Gabrovska K Yordanova G Godjevargova T Grano V Nicolucci C Mita L Bencivenga U Canciglia P Mita DG 《Journal of agricultural and food chemistry》2008,56(23):11471-11477
The catalytic behavior of a mixture of pectic enzymes, covalently immobilized on different supports (glass microspheres, nylon 6/6 pellets, and PAN beads), was analyzed with a pectin aqueous solution that simulates apple juice. The following parameters were investigated: the rate constant at which pectin hydrolysis is conducted, the time (tau(50)) in which the reduction of 50% of the initial viscosity is reached, and the time (tau(comp,dep)) required to obtain complete depectinization. The best catalytic system was proven to be PAN beads, and their pH and temperature behavior were determined. The yields of two bed reactors, packed or fluidized, using the catalytic PAN beads, were compared to the circulation flow rate of real apple juice. The experimental conditions were as follows: pH 4.0, T = 50 degrees C, and beads volume = 20 cm(3). The initial pectin concentration was the one that was present in our apple juice sample. No differences were observed at low circulation rates, while at higher recirculation rates, the time required to obtain complete pectin hydrolysis into the fluidized reactor was found to be 0.25 times smaller than in the packed bed reactor: 131 min for the packed reactors and 41 min for the fluidized reactors. 相似文献
44.
Carlotta Balconi Chiara Lanzanova Elena Conti Tiziana Triulzi Fabio Forlani Marzia Cattaneo Elisabetta Lupotto 《European journal of plant pathology / European Foundation for Plant Pathology》2007,117(2):129-140
The maize gene b-32, normally expressed in the maize (Zea mays) endosperm, encodes for a RIP (Ribosome Inactivating Protein) characterised by antifungal activity. Transgenic wheat plants
were obtained via biolistic transformation, in which the b-32 gene is driven by the 35SCaMV promoter in association with the bar gene as a selectable marker. Plants were brought to homozygosity through genetic analysis of progeny and pathogenicity tests
were performed on the fourth generation. Six homozygous b-32 wheat lines were characterised. All plants had a normal phenotype,
not distinguishable from the control cv. Veery except for slightly smaller size, flowered and set seeds. Western blot analyses
confirmed b-32 expression during the plant life cycle in the various tissues. Each line differed in the b-32 content in leaf
protein extracts and the transgenic protein expression level was maintained at least up to 10 days after anthesis. Pathogenicity
tests for Fusarium head blight (FHB) were performed on the b-32 transgenic wheat lines in comparison to the parental cv. Veery.
Resistance to FHB was evaluated by the single floret injection inoculation method on immature spikes with spores of Fusarium culmorum. In all the transgenic lines, a similar reduction in FHB symptoms, not dependent on the level of b-32 protein, has been observed
(20% and 30% relative to the control, respectively 7 and 14 days after inoculation). Percentage of tombstone kernels at maturity
was also recorded; in all transgenic lines disease control for this parameter was around 25%. The data obtained indicate that
maize b-32 was effective as in vivo antifungal protein reducing FHB symptoms in wheat lines expressing the maize RIP protein. 相似文献
45.
Tiziana Amoriello Valeria Turfani Vincenzo Galli Francesco Mellara Marina Carcea 《Cereal Chemistry》2016,93(4):364-368
Gluten aggregation properties were investigated by means of the GlutoPeak device, a viscometer recently proposed as a rapid and sensitive test for measurement of wheat flour technological performance. In this study, 62 soft wheat flour samples of different quality and end use were utilized to evaluate if the GlutoPeak parameters could adequately predict chemical and rheological characteristics of soft wheat flour dough, that is, protein content measured by the Kjeldahl method, dough strength measured by a Chopin alveograph, and dough stability and water absorption measured by a Brabender farinograph. Linear correlation analysis showed that most GlutoPeak curve parameters were strongly correlated with protein content, dough strength, and water absorption. The statistical models, obtained by a stepwise multiple regression method, showed the GlutoPeak device to be a promising tool to characterize wheat flour (Radj2 = 0.84 for protein content, Radj2 = 0.71 for dough strength, and Radj2 = 0.67 for water absorption). The rather high accuracy of the prediction models for the three mentioned parameters confirmed that GlutoPeak parameters are well correlated with other frequently used flour quality parameters and are able to describe flour technological performance. 相似文献
46.
Salvatore Pisanu Tiziana Cubeddu Daniela Pagnozzi Stefano Rocca Carla Cacciotto Alberto Alberti Gavino Marogna Sergio Uzzau Maria Filippa Addis 《Veterinary research》2015,46(1)
Neutrophil extracellular traps (NETs) are structures composed of DNA, histones, and antimicrobial proteins that are released extracellularly by neutrophils and other immune cells as a means for trapping and killing invading pathogens. Here, we describe NET formation in milk and in mammary alveoli of mastitic sheep, and provide a dataset of proteins found in association to these structures. Nucleic acid staining, immunomicroscopy and fluorescent in-situ hybridization of mastitic mammary tissue from sheep infected with Streptococcus uberis demonstrated the presence of extranuclear DNA colocalizing with antimicrobial proteins, histones, and bacteria. Then, proteomic analysis by LTQ-Orbitrap Velos mass spectrometry provided detailed information on protein abundance changes occurring in milk upon infection. As a result, 1095 unique proteins were identified, of which 287 being significantly more abundant in mastitic milk. Upon protein ontology classification, the most represented localization classes for upregulated proteins were the cytoplasmic granule, the nucleus, and the mitochondrion, while function classes were mostly related to immune defence and inflammation pathways. All known NET markers were massively increased, including histones, granule proteases, and antimicrobial proteins. Of note was the detection of protein arginine deiminases (PAD3 and PAD4). These enzymes are responsible for citrullination, the post-translational modification that is known to trigger NET formation by inducing chromatin decondensation and extracellular release of NETs. As a further observation, citrullinated residues were detected by tandem mass spectrometry in histones of samples from mastitic animals. In conclusion, this work provides novel microscopic and proteomic information on NETs formed in vivo in the mammary gland, and reports the most complete database of proteins increased in milk upon bacterial mastitis.
Electronic supplementary material
The online version of this article (doi:10.1186/s13567-015-0196-x) contains supplementary material, which is available to authorized users. 相似文献47.
Sporadic autonomic dysregulation and death associated with excessive serotonin autoinhibition 总被引:1,自引:0,他引:1
Audero E Coppi E Mlinar B Rossetti T Caprioli A Banchaabouchi MA Corradetti R Gross C 《Science (New York, N.Y.)》2008,321(5885):130-133
Sudden infant death syndrome is the leading cause of death in the postneonatal period in developed countries. Postmortem studies show alterations in serotonin neurons in the brainstem of such infants. However, the mechanism by which altered serotonin homeostasis might cause sudden death is unknown. We investigated the consequences of altering the autoinhibitory capacity of serotonin neurons with the reversible overexpression of serotonin 1A autoreceptors in transgenic mice. Overexpressing mice exhibited sporadic bradycardia and hypothermia that occurred during a limited developmental period and frequently progressed to death. Moreover, overexpressing mice failed to activate autonomic target organs in response to environmental challenges. These findings show that excessive serotonin autoinhibition is a risk factor for catastrophic autonomic dysregulation and provide a mechanism for a role of altered serotonin homeostasis in sudden infant death syndrome. 相似文献
48.
O. Abollino A. Giacomino M. Malandrino E. Mentasti 《Water, air, and soil pollution》2007,181(1-4):149-160
Vermiculite is a natural clay that has many applications as acoustic and thermal insulator, additive in concrete and plaster, fertilizer carrier and adsorbent. Moreover, clay minerals have been studied as adsorbent materials to remove heavy metals from industrial and/or municipal waste waters. In this work we have investigated the possibility to apply vermiculite for the clean-up of extracts resulting from the application of soil washing to a metal-contaminated soil collected from a polluted site in Italy. The soil was initially characterized for its total metal content; we also studied the availability of the pollutants by leaching at pH 5.0 and by Tessier’s sequential extraction procedure. We tested a possible clean-up strategy, in which metals were extracted with hydroxylammonium chloride and vermiculite was used as natural sorbent for the decontamination of the extracting solutions. The possibility of recovering the metals by elution with acid and of reusing the clay was also demonstrated. 相似文献
49.
Montañés F Fornari T Martín-Alvarez PJ Corzo N Olano A Ibañez E 《Journal of agricultural and food chemistry》2006,54(21):8340-8345
A selective fractionation method of carbohydrate mixtures of galactose/tagatose, using supercritical CO(2) and isopropanol as cosolvent, has been evaluated. Optimization was carried out using a central composite face design and considering as factors the extraction pressure (from 100 to 300 bar), the extraction temperature (from 60 to 100 degrees C), and the modifier flow rate (from 0.2 to 0.4 mL/min, which corresponded to a total cosolvent percentage ranging from 4 to 18% vol). The responses evaluated were the amount (milligrams) of tagatose and galactose extracted and their recoveries (percent). The statistical analysis of the results provided mathematical models for each response variable. The corresponding parameters were estimated by multiple linear regression, and high determination coefficients (>0.96) were obtained. The optimum conditions of the extraction process to get the maximum recovery of tagatose (37%) were 300 bar, 60 degrees C, and 0.4 mL/min of cosolvent. The predicted value was 24.37 mg of tagatose, whereas the experimental value was 26.34 mg, which is a 7% error from the predicted value. Cosolvent polarity effects on tagatose extraction from mixtures of galactose/tagatose were also studied using different alcohols and their mixtures with water. Although a remarkable increase of the amount of total carbohydrate extracted with polarity was found, selective extraction of tagatose decreased with increase of polarity of assayed cosolvents. To improve the recovery of extracted tagatose, additional experiments outside the experimental domain were carried out (300 bar, 80 degrees C, and 0.6 mL/min of isopropanol); recoveries >75% of tagatose with purity >90% were obtained. 相似文献
50.
Angelo Rita Francesco Ripullone Tiziana Gentilesca Luigi Todaro Antonio Saracino Marco Borghetti 《Annals of Forest Science》2017,74(3):49