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141.
ABSTRACT

Variations in the levels of the highly toxic oleandrin molecules were studied during composting of Nerium oleander L. waste mixed with clippings of the grass Pennisetum clandistenum L. The thermophilic phase is characterized by a rise in temperature, which reached 70°C. After 150 days of co-composting, the C/N ratio was 11, the pH was 8, the NO3?/NH4+ ratio was greater than 1 and overall decomposition reached 70%. During the successive stages of co-composting, oleandrin concentrations were monitored by HPLC. The relative abundance of oleadrin was 26.84% at T0 with 10% abatement during the first month and 90% after two months (stabilization phase), reaching 100%, i.e., total removal after 90 days of co-composting (maturation phase). The biodegradation of the toxic substance was largely attributed to the activity of actinomycetes and fungi. The germination index of lettuce and watercress seeds exceeded 50% after 90 days and reached 95% after 150 days, confirming that the final compost was mature, stable, and free from phytotoxicity in spite of the highly poisonous starting material.  相似文献   
142.
Journal of Plant Diseases and Protection - The present work aimed to investigate the effect of an autochthonous mycorrhizal consortium in enhancing olive tree tolerance against Verticillium...  相似文献   
143.
This study is a continuation of the previous parts and also deals with the colour tests, free sugars and phenolic aglycones of thirty four plants, ranging from the familyMoraceae toRosaceae, with the aim of identifying the type of tannins present.
Zusammenfassung Diese Arbeit ist eine Weiterführung der vorangegangenen Mitteilungen und befaßt sich ebenfalls mit Farbreaktionen, freien Zuckern und phenolischen Aglykonen von weiteren 34 Pflanzen (Morraceae bis Rosaceae) mit dem Ziel, den Typ des jeweils vorliegenden Tannins zu identifizieren.

Resume Suite du travail précédent. Réactions colorées, sucres libres, aglycones phénoliques de 34 autres espèces végétales (Moracées à Rosacées). Essai d'identification des tannins présents dans chaque échantillon.
  相似文献   
144.
Investigation of four guava cultivars showed that when the fruits were harvested at different stages of growth and development, total sugars increased slowly during the initial growing period followed by rapid increase during maturation and repining for all cultivars. The maximum level varied from 7.5 to 26.9%. Individual sugars: (fructose, glucose and sucrose) increased slowly during the initial growing period followed by rapid increase during maturation and ripening for all cultivars. The cultivars differed in their final sugar content; fructose varied from 5.6 to 7.7%, glucose from 1.9 to 18.1%, and sucrose from 6.2 to 7.8%. Total ash for all cultivars decreased slowly during the initial growing period followed by a sudden increase in the latter stage of maturation and ripening, with maximum level varying from 5.2 to 7.9%. Minerals: Ca, Mg, Na, K and P, for all cultivars decreased slowly during all stages of development. These results suggest that when guava fruits were picked 106–126 days after fruit set it ensures sufficient amount of total sugars and appreciable amount of minerals.  相似文献   
145.
Genetic Resources and Crop Evolution - In order to assess the genetic diversity among six Egyptian rice cultivars and developing cultivars resistant to different rice stem borers, random amplified...  相似文献   
146.
BACKGROUND: The common wasp, Vespula vulgaris (L.), and the German wasp, Vespula germanica (F.), are significant problems in New Zealand beech forests (Nothofagus spp.), adversely affecting native birds and invertebrate biodiversity. This work was undertaken to develop synthetic attractants for these species to enable more efficient monitoring and management. RESULTS: Seven known wasp attractants (acetic acid, butyl butyrate, isobutanol, heptyl butyrate, octyl butyrate and 2,4‐hexadienyl butyrate) were field tested, and only heptyl butyrate and octyl butyrate attracted significantly higher numbers of wasps than a non‐baited trap. Accordingly, a series of straight‐chain esters from methyl to decyl butyrate were prepared and field tested for attraction of social wasps. Peak biological activity occurred with hexyl butyrate, heptyl butyrate, octyl butyrate and nonyl butyrate. Polyethylene bags emitting approximately 18.4–22.6 mg day?1 of heptyl butyrate were more attractive than polyethylene bags emitting approximately 14.7–16.8 mg day?1 of heptyl butyrate in the field. Electroantennogram (EAG) studies indicated that queens and workers of V. vulgaris had olfactory receptor neurons responding to various aliphatic butyrates. CONCLUSION: These results are the first to be reported on the EAG response and the attraction of social wasps to synthetic chemicals in New Zealand beech forests and will enable monitoring of social wasp activity in beech forests. Copyright © 2009 Society of Chemical Industry  相似文献   
147.
In Poland bread as a staple food both made from wheat and rye flour can be a potential product for future fortification with folic acid. The objective of the study was to examine the effect of fermentation and baking on added folic acid and some endogenous folates stability during breadmaking of rye and wheat breads. Breads were produced using the formulation containing enriched flour with 0.2 mg folic acid/100 g product, baker’s yeast and additionally ascorbic acid for wheat bread and lactic acid for rye bread. Folates were extracted with Hepes/Ches buffer (pH = 7.85) followed by destruction of matrix by amylase and protease and deconjugation with rat serum conjugase. Affinity chromatography (FBP bovine milk) was used to purify and concentrate samples. The folates were separated by HPLC with C18 column and with a combination of fluorescence and UV detection. For both rye and wheat breads there was a decrease of folic acid from flour to bread stage. The total losses depend on baking process and ranged from 12 to 21%. Some changes in the level of different native folate forms during the stage of baking process were also observed.  相似文献   
148.
A few studies have illustrated the effects of sodium salt derived from alginic acid on different fish species. However, little is known about the effect of sodium alginate on catfish (Clarias gariepinus). Therefore, this study was performed to assess the use of low molecular weight sodium alginate ( LMWSA) in C. gariepinus. A total of 180 apparently healthy C. gariepinus with a mean body weight of 45 g were randomly divided into three equal groups (D1, D2 and D3). D1 the control group received a control diet, while D2 and D3 received 1% and 3% LMWSA, respectively, for 8 weeks. A challenge test against Aeromonas hydrophila was performed on 15 randomly selected catfish for 15 days. At the end of the experiment, catfish in D3 that received a diet of 3% LMWSA showed significant increases in the final body weight, weight gain and thermal‐unit growth coefficient compared with those in D2 and D1. There was a significant decrease in the erythrogram in D1 after the 4‐day pathogen challenge. A leucogram revealed leucocytosis, heterophilia and lymphocytosis in catfish in D2 and D3 compared with those in D1. After the 4‐day challenge, the following changes took place: lysozyme, nitric oxide, phagocytic activity and the respiratory burst were significantly elevated in catfish that received LMWSA and were more pronounced in D3 than in D1. The mortalities of catfish have been stopped after pathogen challenge from 8‐day in D1 and D2 where at 6‐day in D3. Thus, administration of 1% and 3% LMWSA enhances the growth, immune response and resistance of C. gariepinus against A. hydrophila.  相似文献   
149.
The pharmacokinetics of cefquinome were studied in healthy and Pasteurella multocida‐infected rabbits after a single intramuscular (IM) injection at 2 mg/kg of its sulfate salt. Twelve female New Zealand white rabbits (2.0–2.5 kg) were used; six of them served as controls, and the other six had been infected with P. multocida; the experiments were conducted 1–2 days after nasal inoculation of P. multocida when rabbits showed the signs of respiratory infection. Plasma concentrations of cefquinome were determined using high‐performance liquid chromatography. The values of elimination half‐life, area under the curve, area under the first moment curve, and mean residence time were significantly lower in infected rabbits (0.48 hr, 4.54 hr*μg/ml, 3.63 hr* hr*μg/ml and 0.8 hr, respectively) than healthy rabbits (0.72 hr, 9.11 hr*μg/ml, 9.85 hr* hr*μg/ml and 1.1 hr, respectively), whereas total body clearance was significantly higher in infected than healthy rabbits. Therefore, P. multocida infection caused significant changes in some of the pharmacokinetic parameters of cefquinome in rabbits. These pharmacokinetic changes may affect dose regimen when used in P. multocida‐infected rabbits.  相似文献   
150.
Organic wastes can be usefully recovered to produce organic amendments, for example, compost, to be used for crop production, thus reducing impacts through efficient waste management. The aim of this work was to study the effects of compost obtained from municipal waste in combination with poultry manure on plant growth, nitrate reductase (NR) activity and absorption and distribution of heavy metals (HM) in plant tissues of tomatoes, grown in pots in greenhouses. Two compost types obtained from municipal waste mixed with poultry manure (C1?=?3:2 and C2?=?2:3) were used at two different ages (105 d and 173 d) and at two mix rates with soil (32.5?g pot?1 and 65?g pot?1); soil with no compost amendment was used as control. The experiment was conducted using tomato plants in pots and plant growth and nutrient plant uptake was determined after 65?days from plant transplanting. Results obtained indicated that compost type and compost rate affected biomass production. However, compost age did not influence the development of plants. Nutrient status of tomato plants was also investigated with reference to the N cycle. Nitrite accumulation in the leaves increased with the increase in compost doses. The accumulation of NO2? was associated with a significant increase in NR activity. HM content in leaves decreased with compost use. HM accumulated preferentially in roots and leaves and the soil to root metals transfer was in this order: Fe (1.08–2.14)> Co (0.53–4.10)>Cu (0.28–2.28) >Mn (0.3–1.34) >Zn (0.87–1.21)>Cr (0.12–1.64). The highest and lowest dynamic bioaccumulation factors (BAFdyn) were observed in roots and stems, respectively. The root system acted as a barrier for Cd and Pb. It was concluded that compost use is beneficial for tomato plants, with particular reference to the compost obtained by using a higher amount of poultry manure (C2) in the mix.  相似文献   
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