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91.
The aim of this study was to illustrate the effects of dietary loquat leaf extract (LLE) on the expression of some intestinal cytokines as well as serum innate immune parameters in common carp (Cyprinus carpio) fingerlings. The fish were fed with experimental diets supplemented with 0 (control), 0.25% (0.25LLE), 0.5% (0.5LLE) and 1% (1LLE) LLE over a 7‐week period. At the end of the trial, the serum lysozyme (Lys) activity, ACH50, total Ig as well as the expression of IL1B, IL8, TNF‐alpha, LYZ and TGF‐β in intestine were evaluated. The results showed that administration of 0.5% or 1% LLE significantly increased serum total Ig. However, in case of serum Lys activity significant elevation was observed just in fish fed 0.5% LLE. Also, supplementation of diet with LLE significantly increased ACH50 compared to the control group, regardless of inclusion levels. Gene expression studies revealed upregulation of TNF‐alpha, IL1B, IL8 and LYZ in intestine of fish fed LLE. However, the effects varied dependent on LLE levels and the tested immune related gene. Also, in case of TGF‐β significant downregulation was observed just in 1% LLE treatment. In conclusion, dietary LLE supplementation significantly upregulated immune related genes in intestine and improves innate immune responses. Altogether, LLE can be recommended as fish immunostimulant in early stage of carp culture.  相似文献   
92.
The present study investigates the effects of dietary commercial Bacilli probiotic (Bacillus subtilis and Bacillus licheniformis) on the growth performance, feed efficiency, body composition and immune parameters of Litopenaeus vannamei. The L. vannamei postlarvae were supplied and acclimated (in 500‐L tanks) to laboratory conditions for 14 days. The shrimps were fed with diets containing 1 × 104 and 1 × 108 CFU/g probiotic Bacilli for 60 days. At the end of the feeding trial, growth performance parameters, body composition, serum biochemical parameters and the hemocytes count were evaluated. Shrimps fed diets supplemented with 1 × 104 and 1 × 108 CFU/g probiotic Bacilli showed improved weight gain, total length, specific growth rate, FCR and survival compared with the control group. The body composition studies revealed higher dry matter, crude protein and ash in shrimps fed with 1 × 104 and 1 × 108 CFU/g probiotic Bacilli. Also, dietary administration of 1 × 104 and 1 × 108 CFU/g probiotic Bacilli decreased serum glucose and cortisol levels. However, significantly increased total protein, lysozyme and hemocyte cell count were noticed in shrimps fed 1 × 104 and 1 × 108 CFU/g probiotic Bacilli. In general, the findings of this study proved that oral administration of 1 × 104 and 1 × 108 CFU/g commercial probiotic Bacilli improved growth performance, feed utilization and immune parameters in whiteleg shrimp (Litopenaeus vannamei).  相似文献   
93.
Leaching column experiments were conducted to determine the degree of mobility of heavy metals (HMs) and nutrients after the addition of municipal solid sewage sludge (MSS) in a sandy‐loam soil. Treatments were (1) soil application of low metal content MSS, (2) soil application of metal‐enriched municipal solid sewage sludge (EMSS), and (3) control. The MSS application represented a dose of 200 Mg dry weight (dw) ha–1. Soil columns were incubated at room temperature for 15 d and were irrigated daily with distilled water to make a total of 557 mm. Leachates were collected and analyzed for HMs and nutrients. The Ni and Pb added to soil via MSS and EMSS were found to be leached through the 20 cm columns of calcareous sandy soil although Ni and Pb concentrations in the percolate were small relative to the total amounts of metals applied. Losses of K+ from the EMSS, MSS, and control were 92.5, 82.0, and 52.5 kg ha–1, respectively. Losses of Mg2+ were in the range from 104.4 (control treatment) to 295.2 kg ha–1 (EMSS), while the loss of Ca2+ was in the range from 265.0 (control treatment) to 568.2 kg ha–1 (EMSS). The results showed that the amounts of P leached from EMSS (3.02 kg ha–1) and MSS (2.97 kg–1 ha–1) were significantly larger than those from the control treatment (1.54 kg ha–1). The geochemical code Visual MINTEQ was used to calculate saturation indices. Leaching of P in different treatments was controlled by rate‐limited dissolution of hydroxyapatite, β‐tri‐Ca phosphate, and octa‐Ca phosphate. The results indicate that application of MSS to a sandy soil, at the loading rate used in this study, may pose a risk in terms of groundwater contamination with Ni, Pb, and the studied nutrients.  相似文献   
94.
A whole plant chloroform-methanol extract of the orchid Epidendrum rigidum inhibited radicle growth of Amaranthus hypochondriacus seedlings (IC50 = 300 microg/mL). Bioassay-guided fractionation furnished four phytotoxins, namely, gigantol (1), batatasin III (2), 2,3-dimethoxy-9,10-dihydrophenathrene-4,7-diol (9), and 3,4,9-trimethoxyphenanthrene-2,5-diol (11), along with the known flavonoids apigenin, vitexin, and isovetin and the triterterpenoids 24,24-dimethyl-9,19-cyclolanostane-25-en-3beta-ol (14) and 24-methyl-9,19-cyclolanostane-25-en-3beta-ol (15). Stilbenoids 1, 2, 9, and 11 inhibited radicle growth of A. hypochondriacus with IC50 values of 0.65, 0.1, 0.12, and 5.9 microM, respectively. Foliar application of gigantol (1) at 1 microM to 4 week old seedlings of A. hypochondriacus reduced shoot elongation by 69% and fresh weight accumulation by 54%. Bibenzyls 1 and 2, as well as synthetic analogues 4'-hydroxy-3,3',5-trimethoxybibenzyl (3), 3,3',4',5-tetramethoxybibenzyl (4), 3,4'-dihydroxy-5-methoxybibenzyl (5), 3'-O-methylbatatasin III (6), 3,3',5-trihydroxybibenzyl (7), and 3,4',5-trihydroxybibenzyl (8), were tested for phytotoxicity in axenic cultures of the small aquatic plant Lemna pausicostata. All bibenzyls derivatives except 7 and 8 inhibited growth and increased cellular leakage with IC50 values of 89.9-180 and 89.9-166 microM, respectively. The natural and synthetic bibenzyls showed marginal cytotoxicity on animal cells. The results suggest that orchid bibenzyls may be good lead compounds for the development of novel herbicidal agents.  相似文献   
95.
96.
Excessive accumulation of trace metal in soil represents a growing environmental problem posing severe risks to biota, humans and ecosystems. Concentrations of Cd, Pb, Cu and Zn were determined in soil, as well as in representatives of some trophic levels in the terrestrial food webs in two Egyptian agroecosystems; El-Manzala (a rural area located in the northeast of the River Nile Delta) and El-Tebbin (an industrial area located in South Cairo). Representatives of trophic levels included arthropods, amphibians, reptiles, birds and small mammals. Metal concentrations were determined in the leaves of wild plants, bodies of arthropods and livers of vertebrates. Levels of metals in the soil, plants and most animal species were higher in El-Tebbin than El-Manzala. Minimal concentrations of metals were detected more often in plants and in the cattle egret, whereas maximum values were common in the soil, amphibians and a mantid. Accumulation of metals was more frequent in arthropods and other taxa at lower trophic levels of food webs, suggesting that the transfer of metals along the vertebrate food web may be of relatively minor importance. However, of all the metals examined, only Pb was bioaccumulated to any appreciable extent in some of the higher trophic levels. A significant increase in liver mass and relative liver mass of the Norway rat from the polluted site was observed.  相似文献   
97.
An experiment was conducted to investigate the supplementation of two commercially available multistrain probiotics as an alternative to antibiotics on growth performance, intestinal morphology, lipid oxidation and ileal microflora in broiler chickens. A total of 280‐day‐old ROSS 308 mixed‐sex broiler chickens with an average initial body weight of 42 ± 0.5 g were randomly divided into four treatments with five replicate cages of 14 birds each cage in a completely randomized design and fed with the following diets for 42 day: (a) control (CON) (antibiotic‐free diet), (b) antibiotic (ANT) (CON + Avilamycin 150 g/ton feed), (c) probiotic A (CON + Protexin® 150 g/ton feed) and (d) probiotic B (CON + Bio‐Poul® 200 g/ton feed). The results showed the broilers fed the ANT diet had greater average daily gain than broilers fed the CON diet during day 1–14 (p < 0.05). At day 42, two birds were randomly selected per replicate for evaluation intestinal morphology, lipid oxidation and ileal microflora. birds fed diet supplemented with probiotic A and probiotic B increased villus height and goblet cells numbers in the jejunum and villus height to crypt depth ratio and villus height in the ileum as compared to birds fed CON diet (p < 0.05). The malondialdehyde value was reduced (p < 0.05) in the ANT, probiotic B and probiotic A groups compared with the CON group. The Lactobacillus population was increased and Clostridium spp. population decreased in the ileum of broilers fed diets containing the probiotic B and probiotic A compared with those fed CON diet (p < 0.05). The results from this study indicate that the probiotic A (Protexin®) and probiotic B (Bio‐Poul®) used in this trial may serve as alternatives to ANT.  相似文献   
98.
Abstract

Implementation of proper management practices using biological approaches is important to maintain soil quality and cotton yield in sandy desert soils of Egypt. This experiment was conducted at the Agriculture Experimental farm, Kafer El-Sheikh governorate, Cotton Research Institute of Egypt during 2016–2017 seasons to study the effect of inoculation with bacterial strains of Bacillus circulance (BC) and Bacillus megatherium (BM) and their co-inoculation in combinations with 50% and 100% of recommended dose fertilization (RDF) on growth, yield, and fiber properties of Egyptian cotton Giza-94. Results showed that all important morphological attributes of cotton such as plant growth, number of fruit sympodial branches, number of bolls per plant, boll weight, lint cotton yield and fiber properties significantly increased with the increase rate of RDF, and inoculation of cotton seeds with the bacterial strains exerted additive effects. The highest increase of cotton yield was observed at the combined use of bacterial strains BC?+?BM with 50% RDF followed by BC?+?BM with 100% RDF treatment which attributed on the cotton yield increase by 33% and 15% compared to the respective control. The application of Bacillus strains as a biofertilizer could be an alternative option to reduce considerable amounts of chemical fertilizers input by enhancing nutrient use efficiency (NUE) and, thereby, improves cotton productivity.  相似文献   
99.
A I Hamed 《Fitoterapia》2001,72(7):747-755
Two new pregnane ester glycosides, named stemmoside A (1) and stemmoside B (2) and a third new polyhydroxy pregnane, named stemmin C (3), were isolated from Solenostemma argel leaves. The structures were achieved by extensive one- and two-dimensional NMR and MS spectroscopic analysis.  相似文献   
100.
The objective of this investigation was to introduce a cement-based composite of higher quality. For this purpose new hybrid nanocomposite from bagasse fiber,glass fiber and multi-wall carbon nanotubes(MWCNTs)were manufactured. The physical and mechanical properties of the manufactured composites were measured according to standard methods. The properties of the manufactured hybrid nanocomposites were dramatically better than traditional composites. Also all the reinforced composites with carbon nanotube, glass fiber or bagasse fiber exhibited better properties rather than neat cement.The results indicated that bagasse fiber proved suitable for substitution of glass fiber as a reinforcing agent in the cement composites. The hybrid nanocomposite containing10 % glass fiber, 10 % bagasse fiber and 1.5 % MWCNTs was selected as the best compound.  相似文献   
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