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101.
Field experiments were conducted during the summer seasons of 2011 and 2012 in the Middle Delta of Egypt to compare alterations in saving water and grain yield of transplanted rice in clay loam soil after compaction, wet tillage (puddling) and dry tillage (non-puddling). The results indicate that compacted soil gave higher grain yield, higher irrigation water productivity, higher net income, higher benefit–cost ratio, and less water consumption than wet and dry tillage. The results suggest that soil compaction by four passes of steel plank (2 m long and 600 kg weight) before planting rice is beneficial in terms of saving water and net return. In addition, it can be used instead of the non-puddling method under the conditions of the studied area. Therefore, soil compaction can be considered as a pioneering method of pre-planting soil preparation to increase rice yield and to save irrigation water. It is highly recommended to be used by farmers.  相似文献   
102.
An experiment was conducted to determine whether some non‐nutritive feed additives (NNFA) could block the adverse effects of aflatoxin (AF) on growth performance and physiological parameters of Cobb broilers throughout the period from 1 to 21 day of age. There were eight treatments consisting of two levels of AF at 0 and 200 ppb and four NNFA within each AF level. These additives included mannan oligosaccharides (MOS) at 2 g/kg diet, hydrated sodium calcium aluminosilicate (HSCAS) at 2 g/kg diet and Lactobacillus acidophilus (Lac) at 2 g/kg diet. At 21 day of age, five chickens of each treatment were slaughtered to study dressing percentage and relative weight of inner organs and glands. AF had a significant negative effect on body weight gain (BWG), and feed intake, while impairing feed conversion ratio (FCR). Aflatoxin significantly increased percentage liver, lymphocyte (%), monocyte (%), serum triglyceride level, and the aspartate aminotransferase (AST), and alanine aminotransferase (ALT), concentrations while decreasing dressing percentage, intestinal percentage, white blood cells (WBCs), red blood cells (RBCs), haemoglobin (Hgb), packed cell volume (PCV), heterophil (%), heterophil/lymphocyte ratio, total serum protein and serum albumin. Aflatoxin adversely affected the morphology of the liver, bursa and the thymus. There was a significant interaction between AF and NNFA on the relative weights of liver, heart and intestine. Lac completely blocked the negative effects of AF on the percentage liver and the heart and partially on the intestine. In conclusion, Lac was most effective in reversing the adverse effects of AF on growth and FCR and on the percentage, functions and morphology of the liver. Hydrated sodium calcium aluminosilicate also improved the economic traits of broilers but was less effective than Lac and more effective than MOS.  相似文献   
103.
Kafirin and protein bodies were extracted from a condensed tannin-free white Sudanese cultivar of sorghum (Dabar). The extracted materials were characterized by SDS-PAGE. The potential of kafirin as a tablet matrix for pharmaceutical applications was studied. Tablets composed of kafirin, calcium hydrogen orthophosphate, caffeine and magnesium stearate were prepared by direct compression. The tablets showed appropriate levels of hardness and friability. Drug release studies showed that caffeine dissolution was greater in 0.1 M HCl than in either phosphate buffer (pH = 6.8) or distilled water. Deamidation of the protein in acid conditions might explain this observation.FTIR analysis showed that the secondary structure of kafirin was found to be mainly governed by α helices with some β sheets. Upon tabletting, there was a change in protein conformation, which was recovered upon dissolution irrespective of the dissolution media. This might be explained by the loss of protein coil to coil interaction during tabletting (possibly due to the diluting effect of calcium hydrogen orthophosphate). This was later recovered when tablets were dissolved due to the hydrophobic interactions between the kafirin proteins.In summary, this work has shown that kafirin has a potential for use as a tablet for drug delivery.  相似文献   
104.
The Phoenician juniper (Juniperus phoenicea L.) has long been common in the Al-Akhdar mountain range in NE Libya. Juniper trees in the region are showing signs of dieback, and minimal successful seedling recruitment has occurred. We investigate this effect at the level of individual trees, tree size classes, and populations. At ten sites, population size, growth and reproductive traits, and percentage dieback in different size classes were evaluated. Elevation, distance from the sea, and the interaction between these factors had a significant effect on tree volume, and number of branches, number of female cones per branch and number of female cones per tree. Two groups of populations were recognized: the first (Sites 2, 3, and 4) were near the coast. They appeared to be more recently established, with no individuals in the largest size class, and, at this point, less severe dieback. In contrast, in the rest of the sites there were no individuals (Sites 1, 5, 6, and 9) or very few individuals (Sites 7, 8, and 10) in the smallest size class, indicating widespread failure of recruitment in recent years. Mature female cones containing seeds were abundant at these sites (except for Site 8); therefore, this was not attributable to failure of sexual reproduction, but rather was associated with higher levels of intra- and inter-specific competition, combined with more variable rainfall in recent years. Smaller trees are particularly susceptible to dieback throughout the region. Conservation initiatives should include restrictions on clearing these natural forests for conversion to agriculture and, where harvesting is necessary, preferential harvesting of larger individuals.  相似文献   
105.

Onion (Allium cepa) and leek (Allium ampeloprasum var. porrum) are common herbs and vegetables found in our daily life. It belongs to the genus Allium, which is usually known for their high antioxidant and anticancer properties. Medical researchers highly recommend the exploitation of herbs and plants as alternative ways in the treatment of cancer. This research was designed to study the anticancer effects of onion and leek extracts on MCF-7 human breast cancer cell. Crude extracts of ethanol, methanol, and water of onion and leek were obtained by maceration. MCF-7 cells were cultured in complete media at 37 °C and subjected to different treatments that involved varying concentrations (10, 50, and 100 μg/mL) of onion and leek extracts for 24, 48, and 72 h of incubation. The percentage of cell viability and the concentration of extracts on MCF-7 cells were determined using MTT assay. The water leek extract proved to be the most effective extract at 50 μg/mL, whereby it showed a significant inhibition ability due to the presence of entadamide A-β-D-glucopyranoside as identified by ultra-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry (UPLC-QTOF/MS). Further studies about the mechanism of both extracts in causing cell death and the determination of the presence of other bioactive compounds in the extracts are needed.

  相似文献   
106.
Aphids are considered as one of the key pests for wheat production worldwide. Major aphid species that infest wheat in China include Sitobion avenae, Rhopalosiphum padi, Schizaphis graminum and Metopolophium dirhodum. However, during our wheat field survey in Wenshang County of Shangdong Province, China, we observed that Aphis gossypii can feed on wheat. The damage risk of A. gossypii on wheat was assessed using host shift method. A population of A. gossypii collected from a wheat field in 2015 and another population reared on cotton under laboratory conditions for a decade without exposure to insecticides were used in the study. The results of host shift demonstrated that the A. gossypii colony from wheat has not yet developed wheat specialization. Moreover, the assessment of A. gossypii fitness on wheat and cotton showed that fecundity and net reproductive rate of A. gossypii population fed on wheat was significantly higher comparing to the population fed on cotton, whether the initial host of A. gossypii population was wheat or cotton. This study raises a warning that the cotton aphid has potential to establish well on wheat and it may cause significant effects under specific circumstances. Therefore, future studies are required to evaluate the effects of A. gossypii on wheat production.  相似文献   
107.
An experiment that included some inclusions of corn distillers dried grains with solubles (DDGS) with or without supplementation of probiotic bacteria to Hi‐sex Brown laying hen diets was conducted to evaluate the impacts on performance, egg quality, blood metabolites and nitrogen and phosphorus excretion in the manure. A total of 216 twenty‐two‐week‐old Hi‐sex Brown laying hens were randomly divided into eight treatment groups in a factorial design (4 × 2) experiment, which included four levels of DDGS (0, 50, 100 and 150 g/kg diet) plus two levels of Bacillus subtilis probiotic (0 or 1000 mg/kg diet, with a concentration of 1.5 × 108 CFU/g of dried product). The experimental period extended from 22 to 34 weeks of age. The results showed that linear increase in DDGS level up to 150 g/kg improved (p ≤ 0.01) the values of feed consumption, egg shape index and yolk colour compared to the control and other treatment groups. Inclusion of dietary DDGS up to 150 g/kg in layer diets led to a significant decrease in egg mass and a significant increase in Haugh unit score compared to other groups. In the bacillus group, the values of feed conversion, egg weight and egg mass enhanced by 6.45, 3.27 and 7.60% respectively compared with the control diet. Total protein, albumin, triglycerides, cholesterol, calcium and ammonia in serum were significantly (p ≤ 0.01) influenced by DDGS inclusion. The excreted nitrogen decreased by 8.62 and 4.31% in hens fed 50 or 100 g/kg of DDGS respectively, while excreted phosphorous decreased by 3.33, 7.22 and 10.56% in hens fed 50, 100 or 150 g/kg of DDGS respectively as compared to the control group. It could be concluded that increasing DDGS inclusion level in the diet up to 10% and the supplementation of probiotic bacteria improved the productive performance of laying hens and mitigated the harmful emissions from chicken manure; this means better production within environmentally friendly conditions.  相似文献   
108.
In the present study, a novel eco-friendly production of silk fabrics dyed with different natural dye bath concentrations (40, 80, 120, 160, 200 and 240 g/l) extracted from neem (Azadirachta indica) leaves was developed. The surface morphology of the fabrics was examined by scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) spectroscopy to characterize the chemical structure of the fabrics. The SEM images of the undyed fabric show that the fabric was tightly woven with little porosity between the fibres with dozens of silk threads in orthogonal directions. By increasing the neem concentration, a scale of fine particles grew on the surface of the silk fabrics with little macroscopical defects was demonstrated. The fiber diameters and tightness between filaments were significantly increased. The FTIR displayed that, neem dye does not change the characteristic peaks of the silk fabrics. Also, the evaluation of the antimicrobial activity of the undyed and neem dyed silk fabrics was monitored for Gram positive and Gram negative bacteria in addition to yeasts and fungi by using the agar diffusion method. The comparison between the different dye bath concentrations was based on the inhibition zones obtained after incubation. The antimicrobial activity in leaf extract of neem was estimated in Staphylococcus aureus, Bacillus subtilis and Lactobacillus cereus (Gram positive bacteria); Escherichia coli (Gram negative bacteria); Candida albicans and Candida tropicalis (yeasts); and Aspergillus niger and Fusarium solani (fungi). The results emphasized that, the highest neem dye bath concentration (240 g/l) was found to display good inhibitory effect against the Gram positive and reasonable activity against the Gram negative bacteria. Furthermore, the different dye bath concentrations possess no activities against yeast and fungi. In conclusion, the data reveal that the increase of neem dye concentration does not damage the silk fabric; however, it improves its antimicrobial activity by incorporating with antimicrobial agent. The current study highlighted that using neem leaves had beneficial effect in controlling the pathogenic microbial organisms.  相似文献   
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