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81.
Ribeiro B Rangel J Valentão P Baptista P Seabra RM Andrade PB 《Journal of agricultural and food chemistry》2006,54(22):8530-8537
The organic acids and phenolics compositions of nine wild edible mushrooms species (Suillus bellini, Tricholomopsis rutilans, Hygrophorus agathosmus, Amanita rubescens, Russula cyanoxantha, Boletus edulis, Tricholoma equestre, Suillus luteus, and Suillus granulatus) were determined by HPLC-UV and HPLC-DAD, respectively. The antioxidant potential of these species was also assessed by using the DPPH* scavenging assay. The results showed that all of the species presented a profile composed of at least five organic acids: oxalic, citric, malic, quinic, and fumaric acids. In a general way, the pair of malic plus quinic acids were the major compounds. Only very small amounts of two phenolic compounds were found in some of the analyzed species: p-hydroxybenzoic acid (in A. rubescens, R. cyanoxantha, and T. equestre) and quercetin (in S. luteus and S. granulatus). All of the species exhibited a concentration-dependent scavenging ability against DPPH*. T. rutilans revealed the highest antioxidant capacity. 相似文献
82.
Bennett RN Mellon FA Rosa EA Perkins L Kroon PA 《Journal of agricultural and food chemistry》2004,52(19):5856-5862
Azima tetracantha L. (needle bush; bee sting bush; Salvadoraceae) is used as a food and for various herbal medicines in Africa, India, and Madagascar, but there is very little information on the secondary metabolites in this species. High concentrations of N-methoxy-3-indolylmethyl-glucosinolate, a common glucosinolate of Brassica crops such as Brussels sprouts and broccoli, were found in the roots and seeds of A. tetracantha. Lower concentrations were detected in the stems and young leaves. The roots also contained another indole glucosinolate that was provisionally identified, from MS data and comparison with indole glucosinolate standards, as N-hydroxy-3-indolymethyl-glucosinolate. The roots, stems, and leaves contained neoascorbigen (the condensation product of N-methoxy-indole-3-carbinol and ascorbic acid). The seeds of A. tetracantha contained a complex mixture of 26 flavonoids predominantly as glycosides and acyl-glycosides, with traces of aglycones. The core aglycones of these flavonoids were identified as quercetin, isorhamnetin (3'-O-methylquercetin), rhamnetin (7-O-methylquercetin), and rhamnazin (7, 3'-di-O-methylquercetin). No flavonoids or anthocyanins were detected in other tissues, and procyanidins were undetectable. The dimeric piperidine alkaloids azimine, azcarpine, and carpaine were found in all tissues of A. tetracantha. 相似文献
83.
Purpose
Interestingly, soil is the component of the natural environment in which most hydrophobic organic pollution including polycyclic aromatic hydrocarbons (PAHs) gets accumulated. The aim of the present paper was to determine the effect of soil pollution with PAHs on the elemental composition, spectral properties, and hydrophobic and hydrophilic properties of humic acids. The research was performed on different types of soil samples that were artificially polluted with selected PAHs (anthracene, pyrene, fluorene and chrysene).Materials and methods
The soil samples were polluted with selected PAHs in an amount corresponding to 10 mg PAHs kg?1. The PAHs-polluted soil samples were incubated for 180 and 360 days at a temperature of 20–25 °C and fixed moisture (50 % of field water capacity). Humic acids (HAs) were extracted from the soil samples prior to the incubation (additionally, soils not polluted with PAHs) and after 180 and 360 days of incubation. For isolated HAs, the following analyses were performed: elemental composition, UV–Vis and IR spectra, susceptibility to oxidation, and hydrophilic (HIL) and hydrophobic (HOB) properties were determined using high-performance liquid chromatography.Results and discussion
The research demonstrated that introducing anthracene, fluorene, pyrene and chrysene to soil samples resulted in a change in some of the quality parameters of humic acids. However, the intensity and the direction of those changes were determined by soil properties. The changes of the parameters, once PAHs were introduced, that did not depend on the soil properties were ΔA 665u and ΔA 465u (susceptibility to oxidation at wavelengths of 465 and 665 nm) as well as HIL/ΣHOB. The same tendency in changes in the structure of humic acids, once PAHs were introduced, was also observed based on the Fourier transform infrared spectra pattern.Conclusions
A single pollution of soils with PAHs that leads to changes in the quality parameters of humic acids shows that, as for the soils permanently exposed to pollution with those compounds, significant changes can occur in the properties of humic acids. As a result, it can lead to a change in the functions played by humic acids in the environment. 相似文献84.
Piérri Spolti Luana Schneider Rosa M. V. Sanhueza Jean C. Batzer Mark L. Gleason Emerson Medeiros Del Ponte 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(1):21-29
Sooty blotch and flyspeck is caused by numerous species of fungi that colonize the surface of apple fruit and thereby lower
its market value. Although this disease poses a substantial threat to apple growers’ profitability in some regions, reliable
and cost-effective methods for epidemiological and disease control studies have not been validated, nor are they widely available.
We modified a standard area diagram to aid sooty blotch and flyspeck severity assessments and quantified its impact on accuracy
and precision of visual estimates. Samples of ‘Fuji’ and ‘Mutsu’ fruit were photographed both from the top and laterally.
Severity was assessed from a sub-sample of 160 images using image analysis software. Validation of the diagram was performed
by eight raters who independently assessed severity in two series of selected images representing the lateral view and the
top view, initially unaided and subsequently with the aid of the scale. Severity estimates ranged from 0.4% to 98% (most fruit
had <10% severity). Accuracy and precision of the estimates were significantly improved when using the diagrammatic scale;
concordance correlation coefficient values increased from 0.81 to 0.95. A strong tendency to underestimate severity for the
mid-range to high levels was minimized when using the aid, which also improved reproducibility of the estimates among raters.
In addition to strengthening evidence that a standard area diagram can be used reliably in sooty blotch and flyspeck studies,
we expanded its application to disease assessment in the peduncle region, which enhances the usefulness of the method for
evaluating efficacy of management practices. 相似文献
85.
Colomer I Aguado P Medina P Heredia RM Fereres A Belda JE Viñuela E 《Pest management science》2011,67(10):1237-1244
BACKGROUND: Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) and Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) are among the most serious pests of sweet peppers in greenhouses. Chemical control is difficult because of their high reproductive rates and insecticide resistance, and seasonal inoculative releases of Orius laevigatus (Fieber) and Amblyseius swirskii (Athias‐Henriot) are commonly used to reduce their populations. As chemical treatments are often needed in the crop against other pests, the side effects of methoxyfenozide (an insect growth regulator against lepidopteran pests) and flonicamid (a selective feeding inhibitor against sucking insects) were studied in both beneficial organisms in a commercial greenhouse. RESULTS: Orius laevigatus and A. swirskii were released at commercial rates (4–5 and 100 m?2), and a strong establishment and a very homogeneous distribution were reached. One pesticide treatment with the maximum field recommended concentration of methoxyfenozide and flonicamid (96 and 100 mg AI L?1) was done when they were well established, and their population levels were not affected either immediately or up to 30 days after treatment. CONCLUSION: The results are indicative of no impact of methoxyfenozide and flonicamid on the two natural enemies in the field, and both can be considered as potential alternatives to be included in IPM programmes in sweet pepper. Copyright © 2011 Society of Chemical Industry 相似文献
86.
David Gramaje ngeles Aroca Rosa Raposo Jos García-Jimnez Josep Armengol 《Crop Protection》2009,28(12):1091-1097
The efficacy of fourteen selected fungicides against Phaeomoniella chlamydospora and Phaeoacremonium aleophilum was evaluated in vitro by mycelial growth and conidial germination assays. Azoxystrobin, carbendazim and tebuconazole were the most effective fungicides against P. chlamydospora, while carbendazim and didecyldimethylammonium chloride were the most effective against P. aleophilum. An assay was also conducted with cubiet, hydroxyquinoline sulphate and didecyldimethylammonium chloride to determine their potential to prevent infections caused by these pathogens during the hydration stage in grapevine propagation. The results of this experiment demonstrated that P. chlamydospora and P. aleophilum were able to infect healthy cuttings during the hydration stage and showed that didecyldimethylammonium chloride was consistently the best treatment as a disinfectant soak for grapevine cuttings. Additionally, semi-commercial trials were conducted in two grapevine nurseries to evaluate the effectiveness of several strategies with carbendazim, flusilazole and hydroxyquinoline sulphate at different nursery stages. Soaking planting material in carbendazim during the hydration stage was the most effective treatment since neither P. chlamydospora nor P. aleophilum were isolated from planting material in either nursery. 相似文献
87.
Veridiane da Rosa Gomes Paula Costa Ariza Naida Cristina Borges Francisco Jorge SchulzJr. Maria Clorinda Soares Fioravanti 《Veterinary research communications》2018,42(1):87-94
Urinary tract diseases are among the main reasons for consultation in veterinary clinics and hospitals. It affects animals of any age, breed and gender. Among the diseases that affect this system, urolithiasis is the second largest cause of clinical signs compatible with feline urinary tract disease. The term urolithiasis refers to the presence of uroliths in any region of the urinary tract, but it is more commonly seen in the bladder and urethra. Uroliths are classified based on the type of mineral present in their composition, therefore, quantitative and qualitative analyzes are important for a better therapeutic approach. The animals may suffer from the disease and be asymptomatic, or show nonspecific clinical signs, making the diagnosis difficult. The disease should not be seen as a single problem, but as a consequence of various disorders. As dietary, metabolic, genetic and infectious causes, as well as factors that potentiate the chance of development of uroliths such as breed, age, sex, age range, obesity, sedentary lifestyle, geographic region and climate. Thus, the knowledge of the factors that influence the formation of uroliths, as well as the understanding of the pathophysiology, are key elements for better alternatives of therapy and prevention. The recognition of these factors helps to identify susceptible populations, minimizing exposure and increasing the protection factors, which facilitates the diagnosis and treatment of patients with urolithiasis. The objective of this paper is to present the main risk factors involved in the formation of urinary lithiasis in felines. 相似文献
88.
Trujillo M Mateos R Collantes de Teran L Espartero JL Cert R Jover M Alcudia F Bautista J Cert A Parrado J 《Journal of agricultural and food chemistry》2006,54(11):3779-3785
Antioxidant activities of lipophilic hydroxytyrosyl acetate, palmitate, oleate, and linoleate were compared with those of hydroxytyrosol, alpha-tocopherol, and butylhydroxytoluene (BHT) in both glyceridic matrix and biological systems. Aliquots of a glyceridic matrix spiked with various concentrations of antioxidant were subjected to accelerated oxidation in a Rancimat apparatus operated at 90 degrees C. The relationships between induction time (IT) and antioxidant concentration (mmol/kg) presented by hydroxytyrosol and hydroxytyrosyl acetate, palmitate, oleate, and linoleate were similar. Hydroxytyrosol and its esters showed greater antioxidant activity than alpha-tocopherol or BHT. We also evaluated the capacity of hydroxytyrosyl esters to protect proteins and lipids against oxidation caused by peroxyl radicals, using a brain homogenate as an ex vivo model. All tested compounds showed a protective effect in these systems, which was greater in preventing the generation of carbonyl groups in protein than of malondialdehyde in lipid. Inclusion of a lipophilic chain in the hydroxytyrosol molecule enhanced its antioxidant capacities in this biological model. 相似文献
89.
Flor de María Guillén-Jiménez Alma Rosa Netzahuatl-Muñoz Liliana Morales-Barrera Eliseo Cristiani-Urbina 《Water, air, and soil pollution》2009,204(1-4):43-51
The main purpose of this work was to conduct a kinetic study on cell growth and hexavalent chromium [Cr(VI)] removal by Candida sp. FGSFEP in a concentric draft-tube airlift bioreactor. The yeast was batch-cultivated in a 5.2-l airlift bioreactor containing culture medium with an initial Cr(VI) concentration of 1.5 mM. The maximum specific growth rate of Candida sp. FGSFEP in the airlift bioreactor was 0.0244 h?1, which was 71.83% higher than that obtained in flasks. The yeast strain was capable of reducing 1.5 mM Cr(VI) completely and exhibited a high volumetric rate [1.64 mg Cr(VI) l?1 h?1], specific rate [0.95 mg Cr(VI) g?1 biomass h?1] and capacity [44.38 mg Cr(VI) g?1 biomass] of Cr(VI) reduction in the airlift bioreactor, with values higher than those obtained in flasks. Therefore, culture of Candida sp. FGSFEP in a concentric draft-tube airlift bioreactor could be a promising technological alternative for the aerobic treatment of Cr(VI)-contaminated industrial effluents. 相似文献
90.
Andhika Yudha PRAWIRA Savitri NOVELINA Wartika Rosa FARIDA Huda Shalahudin DARUSMAN Katsuhiko WARITA Srihadi AGUNGPRIYONO Yoshinao Z. HOSAKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2020,82(12):1729
Uncoupling protein 1 (UCP-1) was believed to be an exclusive protein found in the brown adipose tissue of small rodents and humans; however, recent studies show that the expression of UCP-1 protein has been found in the sebaceous glands of the mouse tail and human skin. There are a few reports about the presence of UCP-1 in the sebaceous glands of other rodents, such as the Sunda porcupine (Hystrix javanica), a wild spiny rodent commonly found in Indonesia with a large sebaceous gland. The aim of this study was to identify the presence of UCP-1 in the sebaceous glands on the skin of the Sunda porcupine. The skin from three regions (thoracodorsal, lumbosacral and apex caudal) of eight adult Sunda porcupines was used to detect UCP-1-immunopositive cells through immunohistochemistry. All three regions were found immunopositive to anti-UCP-1 antibody in the sebaceous gland of quill and hair follicles, and the epidermal layer in quill and hair follicles with various intensities. The result of immunohistochemistry revealed that the thoracodorsal and apex caudal region was the most intense immunoreaction followed by the lumbosacral region. These findings proved that the presence of UCP-1 was also identified in the sebaceous glands of other rodent (Hystrix javanica) and regions of the body, which has not been reported previously. 相似文献