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91.
Cantín A López-Gresa MP González MC Moya P Miranda MA Primo J Romero V Peris E Estornell E 《Journal of agricultural and food chemistry》2005,53(21):8296-8301
The capacity of inhibition of the mammalian mitochondrial respiratory chain of brevioxime 5a, a natural insecticide compound isolated from Penicillium brevicompactum culture broth, and another 15 analogue compounds, other oximes 5b and 5c; two diastereomeric pyrrolidines 1c' and 1c' '; five pyrrolines 3c', 3c' ' (diastereomers between them), 3a, 3b, and 6; two oxazines 4c' and 4c' ' (also diastereomers between them); and four pyrrol derivatives 7-10, are analyzed in this paper. Compounds 3b, 3c', 3c' ', 4c', 4c' ', 5b, 5c, 6, and 10 were found to be inhibitors of the integrated electron transfer chain (NADH oxidase activity) in beef heart submitochondrial particles (SMP), establishing that all of them except compound 3b and 6 only affected to complex I of the mitochondrial respiratory chain. The most potent product was 5b, with an IC50 of 0.27 microM, similar to the IC50 values of other known complex I inhibitors. The diastereomeric pairs 1c'/1c' ', 3c'/3c' ', 4c'/4c' ', and 5c have not been previously described. Chemical characterization, on the basis of spectral data, is also shown. 相似文献
92.
Artur Dzialuk Małgorzata Mazur Krystyna Boratyńska Jose M. Montserrat Angel Romo Adam Boratyński 《Annals of Forest Science》2011,68(8):1341-1350
• Introduction, Material and Methods
The genetic structure and diversity of ten natural populations of Juniperus phoenicea L. from the western part of the species range have been studied using random amplified polymorphic DNA (RAPD) markers. 相似文献93.
Jiménez JB Orea JM Montero C Ureña AG Navas E Slowing K Gómez-Serranillos MP Carretero E De Martinis D 《Journal of agricultural and food chemistry》2005,53(5):1526-1530
Resveratrol is known as a grapevine secondary metabolite with fungicide activity. Its exogenous application on harvested grapes resulted in the reduction of microbial flora growth, and consequently, prolonged shelf life, without affecting the nutritional quality of the fruit. Resveratrol treatment also resulted in being effective on fruit that normally does not accumulate such metabolites as, for example, tomatoes, apples, avocado pears, and peppers. As a result, all treated fruits maintained their post-harvest quality and health longer than the untreated ones. This study demonstrates the potential use of resveratrol as a natural pesticide to reduce post-harvest fungi development on a broad spectrum of fruit types. 相似文献
94.
Development of a novel and automated fluorescent immunoassay for the analysis of beta-lactam antibiotics 总被引:4,自引:0,他引:4
Benito-Peña E Moreno-Bondi MC Orellana G Maquieira A van Amerongen A 《Journal of agricultural and food chemistry》2005,53(17):6635-6642
An automated immunosensor for the rapid and sensitive analysis of penicillin type beta-lactam antibiotics has been developed and optimized. An immunogen was prepared by coupling the common structure of the penicillanic beta-lactam antibiotics, i.e., 6-aminopenicillanic acid to keyhole limpet hemocyanin. Polyclonal antibodies raised in rabbits after immunization with this conjugate have been applied for the development of a competitive fluoroimmunoassay (FIA), using a novel fluorescent penicillin {[2S,5R,6R]-3,3-dimethyl-7-oxo-6-[(pyren-1ylacetyl)amino]-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxilic acid, PAAP} as the tracer and penicillin G as the reference antibiotic. Protein A/G covalently bound to an azlactone-activated polymeric support was used for the orientated capture of the antibody-antigen immunocomplexes. Upon desorption from the immunosupport, the emission signal generated by the PAAP-Ab complexes is related to the antibiotic concentration in the sample. The 50% binding inhibition concentration of penicillin G standard curves was at 30 ng mL(-)(1) with a detection limit (10% binding inhibition) of 2.4 ng mL(-)(1) and a dynamic range from 6.0 to 191 ng mL(-)(1) (20-80% binding inhibition) penicillin G. The generic nature of the antiserum was shown by good relative cross-reactivities with penicillin type beta-lactam antibiotics such as amoxicillin (50%), ampicillin (47%), and penicillin V (145%) and a lower response to the isoxazolyl penicillins such as oxacillin, cloxacillin, and dicloxacillin. No cross-reactivity was obtained for cephalosporin type beta-lactam antibiotics (cephapirin), cloramphenicol, or fluoroquinolones (enrofloxacin and ciprofloxacin). The total analysis time was 23 min per determination, and the immunoreactor could be reused for more than 200 cycles without significant loss of activity. The immunosensor has been successfully applied to the direct analysis of penicillin G and amoxicillin in spiked influent and effluent sewage treatment plant water samples with excellent recoveries (mean values for penicillin G and amoxicillin, 99 and 105%, respectively). Results displayed by comparative analysis of the immunosensor with a chromatographic procedure for penicillins showed excellent agreement between both methods. 相似文献
95.
Vallejo F Gil-Izquierdo A Pérez-Vicente A García-Viguera C 《Journal of agricultural and food chemistry》2004,52(1):135-138
Broccoli (Brassica oleracea L. var. italica cv. Marathon) inflorescences are a good source of bioactive compounds, such as phenolics (flavonoids and hydroxycinnamoyl derivatives), glucosinolates, and vitamin C. In this work, these health-promoting compounds were submitted to digestion under in vitro gastrointestinal conditions (pH, temperature, enzyme, and chemical conditions). This technique differentiated among the compounds associated with macromolecules in soluble and insoluble form and those that are freely soluble. In addition, it evaluates the chemical stability of the broccoli compounds under simulated physiological conditions. The gastric digestion of broccoli caused high losses in glucosinolates (69% loss), whereas phenolics and vitamin C presented higher stability under these conditions. Thus, there were no losses in flavonoids, a 7% loss of vitamin C, and a variable rate of loss (6-25%) in hydroxycinnamic acid derivatives. The stability of all of the compounds was affected by the in vitro intestinal conditions. Under the in vitro conditions, flavonoids and hydroxycinnamoyl acid derivatives were of low availability, due to their significant losses under these conditions, at the end of the experiment (84 and 80% loss, respectively). Vitamin C was the metabolite that showed the greater decrease after intestinal digestion (91% loss). Regarding the remaining glucosinolates, these compounds presented higher stability under intestinal conditions, rendering an availability similar to that found for phenolics (75% loss). Therefore, broccoli components were affected by gastric and/or intestinal conditions depending on the type of compound. Thus, glucosinolates were mainly degraded by gastric conditions, whereas phenolic compounds and vitamin C were degraded by intestinal conditions. 相似文献
96.
Recio E Alvarez-Rodríguez ML Rumbero A Garzón E Coque JJ 《Journal of agricultural and food chemistry》2011,59(23):12589-12597
A chemical method for the efficient destruction of 2,4,6-trichloroanisole (TCA) and pentachloroanisole (PCA) in aqueous solutions by using hydrogen peroxide as an oxidant catalyzed by molybdate ions in alkaline conditions was developed. Under optimal conditions, more than 80.0% TCA and 75.8% PCA were degraded within the first 60 min of reaction. Chloroanisoles destruction was followed by a concomitant release of up to 2.9 chloride ions per TCA molecule and 4.6 chloride ions per PCA molecule, indicating an almost complete dehalogenation of chloroanisoles. This method was modified to be adapted to chloroanisoles removal from the surface of cork materials including natural cork stoppers (86.0% decrease in releasable TCA content), agglomerated corks (78.2%), and granulated cork (51.3%). This method has proved to be efficient and inexpensive with practical application in the cork industry to lower TCA levels in cork materials. 相似文献
97.
Feather follicle movement control was studied on feathers of the pectoral tract in the anaesthetized chicken. Dissection of nerves leading to the follicles showed that their origin was at least partially in the sympathetic ganglia. Reflectoric ruffling of feathers could be obtained after adequate stimulation. Intravenous injections of drugs in doses which influenced the circulation gave the following results: Adrenaline caused erection of feathers which was abolished by phentolamine. Noradrenaline caused up and down movements after injection only at high doses. Similar results were obtained by placing of skin pieces in saline containing the drugs. The reaction to drugs was typical always for a given group of feathers. Killing of birds and anaesthesia caused general erection of feathers which was not abolished by phentolamine. The findings suggest that adrenergic synapses are involved in feather follicle movement control, but at least another mechanism (CNS) regulates feather follicle movement. 相似文献
98.
Recent changes in landscape structure and function in a mediterranean region of SW Spain (1950–1984)
Recent economic development has altered landscape structure and function of a mediterranean region in Southwestern Spain.
Intensive agricultural systems have concentrated in the more fertile areas, while marginal ones have been abandoned. As a
result, landscape structure has changed. Consequences of this structural change on landscape processes are discussed. 相似文献
99.
Effect of topical ophthalmic dorzolamide(2%)–timolol(0.5%) solution and ointment on intraocular pressure in normal horses 下载免费PDF全文
100.