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151.
Effects simultaneous and sequential inoculations of Meloidogyne incognita, Ralstonia solanacearum and Phomopsis vexans were studied on the growth, chlorophyll and carotenoid contents of eggplants grown in 25% fly ash and 25% sand mix soil. Plants grown in 25% fly ash mix soil had lesser plant growth than grown in 25% sand ash mix soil. Inoculation of M. incognita / R. solanacearum or P. vexans caused reduction in plant growth, chlorophyll and carotenoid contents in both types of soils but these pathogens in combination caused a greater reduction in than individual inoculation. Inoculation of M. incognita 20 days prior to R. solanacearum caused a greater reduction in plant growth than inoculation of M. incognita prior to P. vexans. Inoculation of P. vexans prior to R. solanacearum caused a lesser reduction in plant growth, chlorophyll and carotenoid contents than inoculation of P. vexans prior to M. incognita. Inoculation of R. solanacearum 20 days prior to M. incognita caused a greater reduction in plant growth, chlorophyll and carotenoid contents than inoculation of R. solanacearum prior to P. vexans. Galling and multiplication of M. incognita was higher in plants grown in 25% sand amended soil than with 25% fly ash soil. R. solanacearum and P. vexans had adverse effects on galling and nematode multiplication. Wilt and blight indices caused by R. solanacearum and P. vexans were 3 respectively. Wilt and blight indices were 4 when two pathogens were inoculated together.  相似文献   
152.
Scopolamine, an anti-muscarinic agent, has been shown to induce amnesia and oxidative stress similar to that observed in the older age. The present study was designed to determine the relationship between the oxidative status and memory improvement in scopolamine injected rats pre-administered with almonds. Rats (n?=?8) in the almond group were administered orally with 400 mg/kg almond suspension for 28 days daily before the intraperitoneal injection of scopolamine (0.5 mg/kg). Passive avoidance task (PAT) was used to assess memory function at the end of treatment. The present study revealed that scopolamine injection significantly impaired the memory function in rats pre-treated with saline which was accompanied by increased oxidative stress as evident by increased brain malondialdehyde (MDA) levels and reduced activities of antioxidant enzymes as compared to healthy controls. Pre-treatment with almond significantly ameliorated scopolamine-induced oxidative stress and memory dysfunction. These findings suggest that dietary supplementation with almonds may have a beneficial effect in reducing the risk of oxidative stress-induced memory loss and delaying or preventing the onset of age-related memory impairment.  相似文献   
153.
Poly(lactic acid) (PLA)/jute fiber biocomposites with: i) untreated jute fiber, ii) NaOH treated jute fiber, and iii) (NaOH+silane) treated jute fibers were prepared by melt extrusion process. Microcellular foaming of the injection molded samples was carried out by using single stage batch process. The effects of jute fiber content as well as that of matrix-fiber phase adhesion, in composites with surface treated jute fibers, on the foam microstructure were studied. Further, water absorption, thickness swelling, and biodegradation behavior of the foamed biocomposites were studied and correlated with their foam microstructures. It was observed that on increasing jute fiber content in PLA/JFU biocomposites, cell density increased from 6.5×107 to 8.1×107, while the cell size and expansion ratio decreased from 40 to 23 μm and 2.41 to 1.45, respectively. Again, on increasing the extent of the jute fiber surface treatment in the biocomposites, cell size and expansion ratio increased from 40 to 78 μm and 2.41 to 2.80 respectively. This study also revealed that the rate of biodegradation accelerated with increase in the jute fiber content in the biocomposites while the same retarded with increase in the extent of jute fiber surface treatment.  相似文献   
154.
Many drinking water utilities that use source waters with significant bromide ion levels are currently seeking disinfection regimes that will minimize the formation of brominated disinfection byproducts while providing adequate disinfection. While ozonation appears to be a promising option for achieving these goals, the uncertainty of future drinking water regulations has developed a need for predicting actual disinfection byproduct formation prior to the costly investment for upgrading existing treatment facilities. The models developed in this paper provide comparisons of ozonation application methods, providing a basis for minimizing bromate and aiding in future design considerations. Theoretical and empirical models for the determination of ozone transferred, dissolved ozone concentrations, and bromate formation have been derived and compared with pilot-scale and full-scale data; a good agreement has been observed between the actual data and the predicted data, showing the validity of these models. True-batch bromate formation more closely simulated pilot-scale and full-scale data. Bromate formation in one stage vs two stage ozone contactors and different reactor configurations have been compared. Ozone gas phase concentration appears to have an effect on bromate formation as well.  相似文献   
155.
In present study, Mn, Fe, Zn, Cu, Co, Pb, Cr, Ni and Cd were analyzed by FAAS in green and black tea samples of locally available in the Pakistani market. Na and K were also determined by Flame Photometer. Tea leaves can be the source of mineral components and trace elements, as well as some undesirable substances due to exposure to the environment. Among the metals tested, K was the most abundant one followed by Na, Mn and Fe. Fortunately, toxic heavy metals, Pb and Cd, had the lowest contents in tea samples and also in tea aqueous extracts. Concentration of heavy metals in tea aqueous extract was markedly lower than their total contents except that of K. The solubility of studied metals in tea aqueous extract varied widely and ranged from 0.0-95%. The lowest ranges of solubility were listed for toxic heavy metals Pb and Cd. The possible uptake of metals by the human body from tea aqueous extract has also been determined. The amounts of metals that one may take up through consumption of tea aqueous extract were found to match the acceptable daily intake even taking into account exposure from air, food and drinking water.  相似文献   
156.
Antagonistic fungi (Aspergillus niger CA and Penicillium chrysogenum CA1), plant growth-promoting rhizobacteria (PGPR) (Burkholderia cepacia 4684 and Bacillus subtilis 7612) and AM fungi (Glomus intraradices KA and Gigaspora margarita AA) were assessed alone and in combination for their effects on the growth of tomato and on the reproduction of Meloidogyne incognita in glasshouse experiments. Application of antagonistic fungus, PGPR, or AM fungus alone or in combination significantly increased the length and shoot dry mass of plants both with and without nematodes. The increase in shoot dry mass caused by Gl. intraradices KA in plants without nematodes was greater than that caused by PGPR or antagonistic fungi. Similarly, the increase in shoot dry mass caused by Bu. cepacia 4684 in plants with nematodes was greater than that caused by P. chrysogenum CA1. Application of Bu. cepacia 4684 caused a 36.1% increase in shoot dry mass of nematode-inoculated plants followed by Ba. subtilis 7612 (32.4%), A. niger CA (31.7%), Gl. intraradices KA (30.9%), Gi. margarita AA (29.9%) and P. chrysogenum CA1 (28.8%). Use of Bu. cepacia 4684 with A. niger CA caused a highest (65.7%) increase in shoot dry mass in nematode-inoculated plants followed by Ba. subtilis 7612 plus A. niger CA (60.9%). Burkholderia cepacia 4684 greatly reduced (39%) galling and nematode multiplication, and the reduction was even greater (73%) when applied with A. niger CA. Antagonistic fungi had no significant effect on root colonization caused by AM fungi. Applying Bu. cepacia 4684 with A. niger CA may be useful in the biocontrol of M. incognita on tomato.  相似文献   
157.
BACKGROUND: Biocontrol achieved by a single biocontrol agent is generally inconsistent under field conditions. The aim of the present study was to increase the competitiveness and efficacy of biocontrol agents by using them together with cattle manure. RESULTS: The effects of antagonistic fungi [Aspergillus niger v. Teigh., Paecilomyces lilacinus (Thom) Samson and Penicillium chrysogenum Thom] and plant‐growth‐promoting rhizobacteria (PGPR) [Azotobacter chroococcum Beijer., Bacillus subtilis (Ehrenberg) Cohn and Pseudomonas putida (Trev.) Mig.] were assessed with cattle manure on the growth of tomato and on the reproduction of Meloidogyne incognita (Kof. & White) Chitwood. Application of antagonistic fungi and PGPR alone and in combination with cattle manure resulted in a significant increase in the growth of nematode‐inoculated plants. The highest increase (79%) in the growth of nematode‐inoculated plants was observed when P. putida was used with cattle manure, followed by use of P. lilacinus plus cattle manure. Paecilomyces lilacinus resulted in a high reduction in galling and nematode multiplication, followed by P. putida, B. subtilis, A. niger, A. chroococcum and P. chrysogenum. The combined use of P. lilacinus with cattle manure resulted in a maximum reduction in galling and nematode multiplication. CONCLUSION: Application of P. lilacinus or P. putida with cattle manure was useful to achieve greater biocontrol of M. incognita on tomato. Copyright © 2009 Society of Chemical Industry  相似文献   
158.
159.
An 8-week growth trial was conducted to assess the effect of dietary protein on growth, feed utilization, protein retention efficiency, and body composition of young Heteropneustes fossilis (10.02 ± 0.09 g; 9.93 ± 0.07 cm). Isocaloric (4.15 kcal g−1, GE) diets with varying levels of protein (25, 30, 35, 40, 45, and 50% of the diet) were fed near to satiation to triplicate groups of fish. Optimum dietary protein was determined by analyzing live weight gain (LWG%), feed conversion ratio (FCR), protein efficiency ratio (PER), specific growth rate (SGR%), and protein retention efficiency (PRE%) data. Maximum LWG% (167), best FCR (1.42), PER (1.75), SGR (1.76), and PRE (31.7%) were evident in fish fed 40% protein diet (Diet 4). Body protein data also supported the above level. However, second-degree polynomial regression analysis of the above data indicated that inclusion of dietary protein in the range of 40–43% is optimum for the growth of young H. fossilis.  相似文献   
160.
A study was undertaken to assess the effect of different storage temperatures on senescence and postharvest performance of isolated flowers of Ranunculus asiaticus L.. The main aim of the work was to develop a cost-effective storage protocol to reduce the postharvest losses and to bring out the transportation of cut flowers of R. Asiaticus. The flowers were subjected to two different storage treatments, dry storage and wet storage, and their postharvest performance was compared under laboratory conditions. For this purpose, the buds were harvested at 8:00 AM at loose bud stage (Stage II of flower development). The harvested buds were cut to a uniform size of 15 cm and processed for dry or wet storage. For dry storage, the buds were packed after wrapping them in moistened filter papers and kept at 5°C and 10°C. For wet storage, the buds were held in distilled water in separate glass beakers kept at 5°C and 10°C, respectively. A separate set of buds each for dry and wet storage was kept at room temperature (15±2)°C. After 72 h storage, the buds were kept at room temperature in distilled water. The average life of an individual flower that opened fully was about 4–5 days. The buds kept under wet storage at 5°C and 10°C for 72 h maintained their premature status, while the buds held at room temperature for 72 h generally bloomed. All the buds stored dry maintained their premature status irrespective of storage temperature. Storage of buds for 72 h at 5°C, followed by transferring to distilled water improved the longevity by about 5 to 6 days. Cold storage treatment before transferring to holding solution improved floral diameter, membrane integrity besides maintaining higher fresh and dry mass of flowers, sugar content, soluble proteins, and phenols. Our results suggested that wet and dry storage of premature buds of R. asiaticus for 72 h at 5°C, followed by placing them in distilled water, improved the cut flower longevity and can be used as effective postharvest storage treatments for this beautiful cut flower.  相似文献   
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