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191.
Fruit juice of a new pigmented citrus hybrid named Omo-31 and those of its parents clementine cv. Oroval (Citrus clementina Hort. ex Tan.) and Moro orange [Citrus sinensis (L.) Osbeck] were analyzed during fruit maturation to determine juice yield, total soluble solids (TSS), total acidity (TA), TSS/TA ratio (classical parameters of quality), and potential health beneficial components, such as vitamin C, flavanones, anthocyanins, and phenolic acids. Results showed that juice yield, TA, TSS, and TSS/TA ratio values of Omo-31 were similar to those of the Moro orange. Vitamin C content of the new hybrid was slightly higher than that of clementine and lower than that of the Moro orange, but at maturity stage no differences were observed among the three genotypes. The phenolic compounds content of the new hybrid and those of the parents and their evolution during maturation were studied. At maturity stage the amount of anthocyanins, flavanones, and hydroxycinnamic acids in Omo-31 was found to be notably higher than those of the parents. The high level of antioxidant substances makes this new fruit important for its nutritional benefits.  相似文献   
192.
Ichthyophthirius multifiliis (Ich), a ciliated protozoan parasite of fish, expresses surface antigens (i-antigens), which react with host antibodies that render them immobile. The nucleotide sequence of an i-antigen gene of I. multifiliis strain ARS-6 was deduced. The predicted protein of 47 493 Da is comprised of 460 amino acids (aa's) arranged into five imperfect repeats with periodic cysteine residues with the structure: CX(19)20CX2CX16−27CX2CX20(21)CX3. The N-terminal aa's typify a signal peptide motif while a stretch of C-terminal aa's resemble a glycosyl–phosphatidyl–inositol (GPI)-anchor addition site. The degree of deduced i-antigen aa sequence identity of strain ARS-6 (GenBank accession # ACH87654 and # ACH95659) with other I. multifiliis i-antigen sequences present in GenBank ranges from 99% to 36% identity with 52 kDa i-antigens of I. multifiliis strain G5 (accession #s AAK94941 and AAK01661 respectively). Immunoblot analysis of i-antigens following exposure of I. multifiliis theronts to catfish anti- I. multifiliis immune serum did not show any appreciable alteration in i-antigen expression. The mechanism that regulates i-antigen expression in I. multifiliis remains a puzzling question.  相似文献   
193.
Mozzarella stretching water (MSW) is a dairy effluent generated from mozzarella cheese production that does not have a real use and is destined to disposal, causing environmental problems and representing a high disposal cost for dairy producers. Spent brewery yeast (SBY) is another promising food waste produced after brewery manufacturing that could be recycled in new biotechnological processes. Aurantiochytrium mangrovei is an aquatic protist known as producer of bioactive lipids such as omega 3 long chain polyunsaturated fatty acids (ω3 LC-PUFA), in particular docosahexaenoic acid (DHA). In this work MSW and SBY have been used to formulate new sustainable growth media for A. mangrovei cultivation and production of DHA in an attempt to valorize these effluents. MSW required an enzymatic hydrolysis to enhance the biomass production. The new media obtained from hydrolysed MSW was also optimized using response surface methodologies, obtaining 10.14 g L−1 of biomass in optimized medium, with a DHA content of 1.21 g L−1.  相似文献   
194.
Filtered sea water was seeded with one of five oyster-pathogenic bacteria to obtain a final concentration of 105 cells/ml. UV irradiation at a dose of 93 312–155 520 μW s?1 cm?2 rendered the contaminated sea water safe for rearing fertilized eggs of Crassostrea virginica. Fertilized oyster eggs were reared until the larvae began to set in filtered, UV-irradiated sea water and in filtered, non-UV-treated sea water. The data suggest that when a pathogenic bacterium is present the potential for disease is much greater in non-UV-treated sea water.  相似文献   
195.
There is a question whether it is best to use synthetic or alternative materials to fertilize horticultural crops. Levels of applied fertilizer can affect development of crops such as banana squash (Curcubita maxima Duch.). Seed were planted in 1990, 1991, and 1992 into beds treated with sufficient fertilizer to raise the residual nutrient levels to the recommended (base) and twice recommended (2X) rate with a synthetic or an alternative fertilizer. Lime was applied prior to seeding in 1990 and as a treatment was, or was not, applied prior to seeding in 1991 and 1992. Plants grown in beds treated with the synthetic fertilizer consistently produced higher yields than plants grown in beds treated with the alternative fertilizer. In 1990, the base fertilizer rate improved yield. There was no difference in 1991 due to fertilizer level, and in 1992, the 2X fertilizer rate improved yield. Application of fertilizer above the base level is not encouraged. Liming did not affect yield. By the spring of 1992, the soil pH for lime augmented fertilizer treatments was increased above the spring 1991 levels which was maintained through fall 1992. For the no‐lime treatments, soil pH by fall 1992 was below spring 1991 levels. Soil pH was not correlated with yield. These data suggest that factors which would include solubility, mineralization, and leaching of materials may be responsible for yield differences between plants fertilized with synthetic or an alternative fertilizer.  相似文献   
196.
In this study we investigated the effect of an ethanolic extract of propolis, with and without CAPE, and some of its components on cyclooxygenase (COX) activity. Propolis (0.00003-0.03%) significantly and concentration-dependently inhibited COX activity from lung homogenate of saline- or LPS-treated rats. Same results were obtained with CAPE (0.1-100 microM). COX activity from lung homogenate of saline- or LPS-treated rats was also inhibited by galangin (0.1-100 microM), although the inhibition induced by the lowest concentration was not significant. Caffeic, ferulic, cinnamic and chlorogenic acids and pinocembrin, (0.1-100 microM) did not affect COX activity. The inhibition curves showed that CAPE and propolis were equipotent inhibitors, whereas galangin was significantly (P<0.001) less potent than propolis and CAPE. In order to better investigate the role of CAPE, we tested the action of an ethanolic extract of propolis (0.00003-0.03%) without CAPE. This extract significantly and concentration-dependently inhibited COX activity from lung homogenate of saline- or LPS-treated rats, however, it resulted to be approximately 10 times less potent than the extract containing CAPE. The analysis of the inhibition curves of the extract with and without CAPE showed a significant (P<0.001) difference. These results suggest that both CAPE and galangin contribute to the overall activity of propolis, CAPE being more effective.  相似文献   
197.
The combination of alder (Alnus acuminata H.B.K.) with pastures, mainly Pennisetum clandestinum (kikuyu grass) and P. Purpureum (elephant grass) is a traditional practice in Costa Rican dairy highlands (between 1300–2500 masl). People believe that the pasture grows greener under the trees [Combe, 1979]. Alder is not only advantageous for fodder production but also for fuelwood and timber. It produces an additional source of income to the small farmer. The potential area for this association was first estimated in 60,000 ha [Combe, 1979], but more recent estimations give figures of around 50,000 ha, including one third of this area in pastures already planted with alder [Canet, 1985]. The question of whether the species may have potential for use in agroforestry systems in countries other than Costa Rica and research needs for the species are also discussed.  相似文献   
198.
The use of pollarded Erythrina poeppigiana as shade tree in coffee plantations is apparently an old practice in Costa Rica. The tree is not native to this country but was introduced between late 19th and 20th century and was rapidly dispersed in the coffee and cacao areas. Currently, the Erythrina tree is widespread in the Turrialba Valley (elevation 600—1300m) and in the Central Valley (elevation 1200m) where the species is always associated with present or past coffee crops. Pollarding carried out by Costa Rican farmers constitutes a long dated and functional practice, hence the objective of this study was to evaluate the amount of biomass produced by pollarding of Erythrina poeppigiana used as shade in coffee crop planted at a density of 280 trees/hectare under different pollarding frequencies. Results showed that by pollarding once a year, 18,470 kg of dry matter per hectare are produced; with two pollardings per year 11,800 kg/ha are produced and with three pollarding per year 7,850 kg/ha are produced. The total amount of nitrogen removed is very similar for pollarding once and twice a year, but is lower for three times a year. The amount of nitrogen removed was approximately 230 kg/ha/year in the first two cases and 170 kg/ha/year in the last one.The above observations suggest that a considerable supply of nutrients exist in the systems with shade trees, when they are periodically pollarded.Finally some conclusions and follow up activities related to research on the species are suggested, such as higher biomass production techniques, appropriate planting practices, selection of genetic material, nutrient depletion when biomass is harvested, conversion of leaves to marketable feed sources (flour, pellets), alley cropping and green manure production and restoration of degraded areas and improductive savannas by planting large cuttings that would improve the soil by adding biomass and shade out undesirable grasses.This work is part of a Ph.D. Dissertation submitted to the Southeastern University, New Orleans, Lousiana by R.O. Russo.  相似文献   
199.
We have studied the effect of propolis and its main active ingredient caffeic acid phenetyl ester (CAPE) on formation of aberrant crypt foci (ACF) and tumors in the rat colon in vivo. CAPE (50 mg/kg i.p.) reduced the formation of ACF and tumor induced by azoxymethane, while propolis ethanolic extract was without effect. These results suggest a potential anti-carcinogenesis of CAPE but not propolis.  相似文献   
200.
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