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991.
Guido LF Curto AF Boivin P Benismail N Gonçalves CR Barros AA 《Journal of agricultural and food chemistry》2007,55(3):728-733
Malt is known to have an impact on beer flavor stability mainly due to the presence of antioxidants. In this study, five barley varieties were malted at industrial and micro scale, and quality parameters of the resulting malts were measured (diastatic power, friability, beta-glucan content, antiradical power, reducing power, lipoxygenase activity, and nonenal potential) and correlated with the sensory data obtained for the corresponding fresh and forced aged beers. A statistical strategy using multiple linear regressions was applied to explore relationships between the malt chemical parameters and beer sensory data, showing antiradical power as the major contribution of malt to beer flavor stability. Additionally, the measured antiradical power, which is well correlated with the polyphenolic content, was found to be very similar for malt and barley, emphasizing the key role of barley endogenous polyphenols. 相似文献
992.
Angeloni C Maraldi T Ghelli A Rugolo M Leoncini E Hakim G Hrelia S 《Journal of agricultural and food chemistry》2007,55(18):7553-7558
alpha1-Adrenergic stimulation triggers glucose transport in the heart through the translocation of glucose transporter (GLUT) 1 and GLUT4 to plasma membranes, mediated by protein kinase C (PKC) isoforms. Evidence is emerging that dietary polyphenolic compounds may act not only as antioxidants but also by modulating PKC-mediated signaling. This study evaluated the ability of a green tea extract (GTE) to modulate alpha1-adrenoceptor-mediated glucose transport in rat cardiomyocytes. GTE supplementation decreased phenylephrine (PhE)-stimulated glucose uptake and GLUT4 recruitment. PhE stimulation activated PKC alpha, beta, delta, and epsilon, while GTE supplementation decreased the translocation of beta and delta isoforms, but not alpha and epsilon, supporting the notion that GTE directly affects PKC activation and is a beta and delta isoform-selective PKC inhibitor. Due to reactive oxygen species (ROS) involvement in pathological heart alterations, the observation that GTE is able to both inhibit effects originated by some PKC isoforms and counteract ROS deleterious effects could be important in the prevention/counteraction of these diseases. 相似文献
993.
Effects of microwave cooking conditions on bioactive compounds present in broccoli inflorescences 总被引:2,自引:0,他引:2
López-Berenguer C Carvajal M Moreno DA García-Viguera C 《Journal of agricultural and food chemistry》2007,55(24):10001-10007
Cooking as a domestic processing method has a great impact on food nutrients. Most Brassica (Brassicaceae, Cruciferae) vegetables are mainly consumed after being cooked, and cooking considerably affects their health-promoting compounds (specifically, glucosinolates, phenolic compunds, minerals, and vitamin C studied here). The microwave cooking process presents controversial results in the literature due to the different conditions that are employed (time, power, and added water). Therefore, the aim of this work was to study the influence of these conditions during microwave cooking on the human bioactive compounds of broccoli. The results show a general decrease in the levels of all the studied compounds except for mineral nutrients which were stable under all cooking conditions. Vitamin C showed the greatest losses mainly because of degradation and leaching, whereas losses for phenolic compounds and glucosinolates were mainly due to leaching into water. In general, the longest microwave cooking time and the higher volume of cooking water should be avoided to minimize losses of nutrients. 相似文献
994.
Pérez RA Iglesias MT Pueyo E Gonzalez M de Lorenzo C 《Journal of agricultural and food chemistry》2007,55(2):360-365
The amino acid composition of 53 honey samples from Spain, consisting of 39 floral, 5 honeydew, and 9 blend honeys, has been determined. Physicochemical characteristics, polyphenolic content, amino acid composition, and estimation of the radical scavenging capacity against the stable free radical DPPH of the honey samples were analyzed. The resulting data have been statistically evaluated. The results showed that pH, acidity, net absorbance, electrical conductivity, and total polyphenolic contents of the honeys showed a strong correlation with the radical scavenging capacity. The correlation between the radical scavenging capacity of honey and amino acid contents was high with 18 of the 20 amino acids detected, with correlation values higher than those obtained for polyphenolic content. These results suggest that the amino acid composition of honey is an indicator of the sample's scavenging capacity. 相似文献
995.
996.
Genovese MI Barbosa AC Pinto Mda S Lajolo FM 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(2):53-58
The knowledge of the contents and profile of isoflavones present in soy protein ingredients, as well as the effect of industrial
processing, is important for the development of functional foods rich in these compounds. The results obtained here showed
that the total isoflavone content varied significantly among products. For defatted and whole soy flours the total isoflavone
content ranged from 120 to 340 mg/100 g, for soy protein isolates from 88 to 164 mg/100 g, and for commercial textured soy
proteins, from 66 to 183 mg/100 g (wet basis, expressed as aglycones). The highest isoflavone content was found for soy hypocotyl
flours, from 542 to 851 mg/100 g. Compared to hypocotyl and whole and defatted flours, soy ingredients presented a decrease
of malonylglycosides and deesterified β-glycosides with a significant increase in the percentage of aglycones, mainly for
soy fibers (65–76%). While defatting was shown to cause isoflavone concentration without altering conjugation, extrusion process
caused destruction of isoflavones and a significant increase in the amount of acetylglycosides, but this effect was less intense
for the concentrates. From the results obtained it can be concluded that differences in isoflavone concentration and profile
may be related to oscillations in the isoflavone content present in the raw material and to the type of processing. 相似文献
997.
Leukemia, i.e., the neoplasia of one or more cell lines of the bone marrow, although less
common than in other species, it is also reported in horses. Leukemia can be classified
according to the affected cells (myeloproliferative or lymphoproliferative disorders),
evolution of clinical signs (acute or chronic) and the presence or lack of abnormal cells
in peripheral blood (leukemic, subleukemic and aleukemic leukemia). The main
myeloproliferative disorders in horses are malignant histiocytosis and myeloid leukemia,
the latter being classified as monocytic and myelomonocytic, granulocytic, primary
erythrocytosis or polycythemia vera and megakaryocytic leukemia. The most common
lymphoproliferative disorders in horses are lymphoid leukemia, plasma cell or multiple
myeloma and lymphoma. Lymphoma is the most common hematopoietic neoplasia in horses and
usually involves lymphoid organs, without leukemia, although bone marrow may be affected
after metastasis. Lymphoma could be classified according to the organs involved and four
main clinical categories have been established: generalized-multicentric,
alimentary-gastrointestinal, mediastinal-thymic-thoracic and cutaneous. The clinical
signs, hematological and clinical pathological findings, results of bone marrow aspirates,
involvement of other organs, prognosis and treatment, if applicable, are presented for
each type of neoplasia. This paper aims to provide a guide for equine practitioners when
approaching to clinical cases with suspicion of hematopoietic neoplasia. 相似文献
998.
Esch F Fabris S Zhou L Montini T Africh C Fornasiero P Comelli G Rosei R 《Science (New York, N.Y.)》2005,309(5735):752-755
The high performance of ceria (CeO2) as an oxygen buffer and active support for noble metals in catalysis relies on an efficient supply of lattice oxygen at reaction sites governed by oxygen vacancy formation. We used high-resolution scanning tunneling microscopy and density functional calculations to unravel the local structure of surface and subsurface oxygen vacancies on the (111) surface. Electrons left behind by released oxygen localize on cerium ions. Clusters of more than two vacancies exclusively expose these reduced cerium ions, primarily by including subsurface vacancies, which therefore play a crucial role in the process of vacancy cluster formation. These results have implications for our understanding of oxidation processes on reducible rare-earth oxides. 相似文献
999.
Chelinho Sónia Moreira-Santos Matilde Lima Débora Silva Cátia Viana Paula André Sandra Lopes Isabel Ribeiro Rui Fialho Arsénio M. Viegas Cristina A. Sousa José P. 《Journal of Soils and Sediments》2010,10(3):568-578
Journal of Soils and Sediments - To mitigate the environmental effects of atrazine, one of the cleanup strategies available is based on the use of atrazine-degrading bacteria. This work aimed to... 相似文献
1000.
Suzanne Higgins Saskia D. Keesstra Žydrė Kadziuliene Lionel Jordan-Meille David Wall Alessandra Trinchera Heide Spiegel Taru Sandén Andreas Baumgarten Johannes L. Jensen Juliane Hirte Frank Liebisch Susanne Klages Philipp Löw Katrin Kuka Maarten De Boever Karoline D'Haene Sevinc Madenoglu Hesna Özcan Wieke Vervuurt Janjo de Haan Willem van Geel Bo Stenberg Pascal Denoroy Rok Mihelič Alar Astover Raquel Mano Cristina Sempiterno Fatima Calouro Giuseppe Valboa Helena Aronsson Tore Krogstad Stanislav Torma Jose Gabriel Peter Laszlo Nils Borchard Bartosz Adamczyk Anna Jacobs Beata Jurga Bożena Smreczak Bruno Huyghebaert Morgan Abras Raimonds Kasparinskis Eloise Mason Claire Chenu 《European Journal of Soil Science》2023,74(5):e13422
The European Commission has set targets for a reduction in nutrient losses by at least 50% and a reduction in fertiliser use by at least 20% by 2030 while ensuring no deterioration in soil fertility. Within the mandate of the European Joint Programme EJP Soil ‘Towards climate-smart sustainable management of agricultural soils’, the objective of this study was to assess current fertilisation practices across Europe and discuss the potential for harmonisation of fertilisation methodologies as a strategy to reduce nutrient loss and overall fertiliser use. A stocktake study of current methods of delivering fertilisation advice took place across 23 European countries. The stocktake was in the form of a questionnaire, comprising 46 questions. Information was gathered on a large range of factors, including soil analysis methods, along with soil, crop and climatic factors taken into consideration within fertilisation calculations. The questionnaire was completed by experts, who are involved in compiling fertilisation recommendations within their country. Substantial differences exist in the content, format and delivery of fertilisation guidelines across Europe. The barriers, constraints and potential benefits of a harmonised approach to fertilisation across Europe are discussed. The general consensus from all participating countries was that harmonisation of fertilisation guidelines should be increased, but it was unclear in what format this could be achieved. Shared learning in the delivery and format of fertilisation guidelines and mechanisms to adhere to environmental legislation were viewed as being beneficial. However, it would be very difficult, if not impossible, to harmonise all soil test data and fertilisation methodologies at EU level due to diverse soil types and agro-ecosystem influences. Nevertheless, increased future collaboration, especially between neighbouring countries within the same environmental zone, was seen as potentially very beneficial. This study is unique in providing current detail on fertilisation practices across European countries in a side-by-side comparison. The gathered data can provide a baseline for the development of scientifically based EU policy targets for nutrient loss and soil fertility evaluation. 相似文献