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611.
Fall armyworm (FAW, Spodoptera frugiperda) emerged as a major lepidopteran pest destroying maize in sub-Saharan Africa. A diallel mating design was used to generate 210 experimental hybrids from 21 lines. Experimental hybrids and four checks were evaluated in two locations. Commercial checks suffered higher foliar and ear damage compared to the top 15 hybrids. Mean squares associated with the genotypic variation were higher than genotype-by-environment interactions for foliar and ear damage traits. Heritabilities were moderate to high. Significant correlations were observed between grain yield (GY) with ear rot (−0.54) and ear damage (−0.45). Positive and significant GCA effects were observed for GY in seven parental lines, which were developed from multiple insect resistance breeding programmes. CKSBL10153 has the highest GCA value for GY and shows significant GCA effects for foliar and ear damage traits. These lines were identified as the ideal combiners for GY and FAW resistance and are therefore recommended for utilization as testers in the development of FAW-resistant three-way cross-hybrid maize with correlated response for increased GY. GCA and marker-based prediction correlations of GY were 0.79 and 0.96, respectively. Both GCA effects and marker-based models were effective in predicting hybrid performance for FAW resistance.  相似文献   
612.
The aim of this study was to evaluate the perioperative effects of robenacoxib on serum C-reactive protein (CRP) and iron concentrations in dogs undergoing gonadectomy. In a prospective, blinded, controlled clinical trial, 60 healthy dogs were randomly assigned to receive preoperative subcutaneous injection of either robenacoxib [2 mg/kg body weight (BW)], meloxicam (0.2 mg/kg BW), or saline (0.04 mL/kg BW), followed by oral administration over 72 h (robenacoxib: 2 to 4 mg/kg BW; meloxicam: 0.1 mg/kg BW; saline: gelatin capsules). Blood samples were taken before surgery and 12, 24, 48, 72 h, and 7 d after surgery. Pain scores were assessed via the short-form Glasgow Composite Pain Scale over 72 h postoperatively. C-reactive protein (CRP) and iron serum levels increased and decreased (P < 0.01, both), respectively, after surgery and returned to baseline within 1 wk. No differences were observed among treatments (P > 0.05) or based on surgery/gender (P > 0.05). Pain assessment revealed a higher incidence of treatment failure in saline (6 females versus 2 and 1 female in robenacoxib and meloxicam, respectively). In conclusion, robenacoxib and meloxicam had no influence on postoperative CRP or iron in dogs, which suggests that these nonsteroidal anti-inflammatory drugs (NSAIDs) do not have a relevant effect on these biomarkers.  相似文献   
613.
Outdoor microcosm tanks were used to grow the penaeid blue shrimp, Litopenaeus stylirostris, in Brunei Darussalam. The tanks were cylindrical, free standing fiber glass tanks of 1827 L water holding capacity and had a self-cleaning mechanism. In three eight-week feeding trials, juvenile shrimp of 0.9–4.3 g were stocked at a density of 28 shrimp/m2. At the end of each trial, survival rates exceeded 80%. Growth rates ranged from 1.19 to 2.46 g/week. Water quality remained stable and within suitable ranges for L. stylirostris growth in all trials. The tanks had algae and bacterial floc developing within a few days of starting the trials. Fourteen commercial shrimp feeds, each containing more than 40% crude protein, were tested in the trials. In spite of the presence of natural food organisms, significant feed-related differences among treatments were found in each trial. In conclusion, microcosm tanks support excellent growth and survival of L. stylirostris and are appropriate for conducting trials to evaluate feeds for pond growout.  相似文献   
614.
Commercial soybean hulls (14.6% crude protein) were pin milled and then air classified into five fractions to determine whether the hull structure can be disrupted and the protein constituents concentrated. The number of pin millings had only a small effect on the weight distribution of the five fractions. After one grinding, the sum of fractions 1 and 2 (<15–18 μm) represented only 3% of total hulls, and on three grindings, they amounted to only 6% of the hulls. Fraction 3 (19–24 μm) shifted from 16 to 20% with three grindings, while fraction 4 (25–30 μm) remained unchanged at 5%. Fraction 5 (>30 μm) shifted from 75 to 69% on three pin millings to compensate for the shifts noted in fractions 1–3. Scanning electron microscopy revealed that fractions 1 and 2 consisted of the parenchymal cell layers (innermost portion) of the hulls; these fractions had three times the protein content and more than twice the amount of lipids found in the ground starting material. Fraction 3 contained many of the hourglass cells typically found in the middle layer of the hulls plus parenchyma cell material and exhibited about twice the amount of protein and lipid found in the starting hulls. Fraction 4 included large hourglass cells plus globular material and contained about twice the amount of protein and about one and one‐half times the lipid of the starting material. Fraction 5 consisted primarily of clumps of palisade cells (outer cellular layer) adhering to each other and had a lower protein and lipid content than the starting hulls. Thus, pin milling causes some selective disruption of the hulls where parenchyma cell layers and hourglass cells are partially released. The palisade cells, however, are the most difficult to disrupt and constitute the fraction most resistant to pin milling. Our findings suggest that pin milling soybean hulls in combination with air classification can be used to concentrate the proteins and lipids in the fines fractions.  相似文献   
615.
Plant Foods for Human Nutrition - The Japanese traditional fermented soybean or “natto”, a cheap and nutrient-rich food, is very popular in Japan. The low-phytate (LP) soybeans exhibit...  相似文献   
616.
Purpose

Monitored natural recovery (MNR) combined with a thin-layer cap (TLC), often referred to as enhanced monitored natural recovery (EMNR), has the potential to accelerate and improve the effectiveness of MNR as a remedial strategy while minimizing widespread disturbance to the existing habitat. This study evaluated the effectiveness of a nominal 15-cm thin-layer sand cap as an EMNR remedial strategy to address sediments that were moderately contaminated with the chlorinated pesticide dichlorodiphenyltrichloroethane and its derivatives, collectively DDX.

Materials and methods

Physical, chemical, and biological measurements were conducted pre-remedy placement and 2, 14, and 25 months post-placement. Measurements were used to evaluate (1) TLC stability; (2) bottom-up mixing of the TLC; (3) advection through the TLC; (4) characteristics of newly deposited sediment atop the EMNR layer compared to pre-remedy surface sediment conditions; (5) changes in contaminant bioavailability; and (6) physical impacts to the benthic community.

Results and discussion

Significant reductions were observed from measurements conducted pre- and post-placement in surface sediment (84–97%), porewater (33–75%), and tissue concentrations (Lumbriculus variegatus deployed in situ) (72–82%). A 63 to 72% decrease in DDX depositional mass flux also was observed. Multiple lines of evidence indicated that the TLC material remained stable. Deposition of suspended material with low concentrations of DDX influenced low concentrations in the surface sediments. No adverse effects were observed on the benthic invertebrate community after TLC placement, and ecological metrics indicated increases in benthic community health, even in the short time period (2 months) following TLC placement.

Conclusions

This demonstration showed that EMNR can be effective at reducing biological exposure in surface sediments while minimizing short-term disturbances to benthic communities at sites where MNR is a remedy option, but natural deposition rates are inadequate to achieve cleanup goals within a reasonable timeframe.

  相似文献   
617.
The recent rise in oil prices has brought renewed attention to energy savings in the fishing industry, and particularly in trawling. Coastal trawlers spend most of their time on fishing grounds near the coast. In such cases, the most successful energy-saving modifications ought to result from changes in the fishing gear and towing conditions. The purpose of this study was to identify the energy-economy potential for Portuguese fish trawlers after altering a vessel's operating conditions and improving its trawl gear performance. Two trawlers, named Tricana de Aveiro and João Macedo were selected as subjects in this project. Both vessels work with gear of similar design and size. Experimental sea trials were carried out to elucidate the actual vessel and gear performance. A model trawl was then built and tested in a flume tank, which provided the basis for improving the gear design. Full-scale trials were then carried out with both vessels using the modified trawls in order to assess changes in gear performance. The new trawls maintained their previous ability to catch species of different ecological groups and consumed less fuel at the same commercial trawling speed. An economic study showed potential increases in the net cash flow (NCF) of up to 27% over the range of operational navigation and trawling speeds. Having demonstrated the performance of the new trawls, the skippers of both vessels subsequently adopted the new design for commercial fishing.  相似文献   
618.
The effects of wounding oil glands of lemon [Citrus limon (L.) Burm.] fruit were investigated. Young mature-green lemons demonstrated significantly lower decay incidence than older yellow fruit when their oil glands were punctured in the presence of postharvest wound pathogen Penicillium digitatum Sacc. Contact with the released gland content on the green lemon surface reduced the viability of P. digitatum spores approximately twice. Wounding caused rapid production of limonene hydroperoxides that persisted for only a few minutes. The magnitude depended on the physiological maturity of the fruit; mature-green fruit produced much higher levels than did yellow lemons. Furthermore, wounding of the oil glands or injection of limonene hydroperoxides into the lemon peel elicited the production of the citrus fruit phytoalexins, scoparone and scopoletin, to levels known to be effective in reducing decay caused by P. digitatum. The mature-green fruit produced about twice as much of these phytoalexins as the older yellow fruit. This induced defensive elicitation of phytoalexin production, as well as the direct effects of these antifungal compounds, markedly inhibited the pathogen in mature-green fruits but was ineffective in older yellow ones.  相似文献   
619.
The work described here concerns a study of the chemical and biochemical transformations in sherry vinegar during the different aging stages. The main factors that contribute to the nature and special characteristics of sherry vinegar are the raw sherry wine, the traditional process of acetic acid fermentation in butts (the solera system), and the physicochemical activity during the aging process in the solera system. A number of chemical and biochemical changes that occur during sherry vinegar aging are similar to those that take place in sherry wine during its biological activity process (where the wine types obtained are fino and manzanilla) or physicochemical activity process (to give oloroso wines). Significant increase in acetic acid levels was observed during the biological activity phase. In addition, the concentrations of tartaric, gluconic, succinic, and citric acids increased during the aging, as did levels of amino acids and acetoin. A color change was also produced during this stage. Glycerol was not consumed by acetic acid bacteria, and levels of higher alcohols decreased because of the synthesis of acetates. On the other hand, in the physicochemical phase the microbiological activity was lower. Concentrations of some cations increased because of evaporation of water through the wood. A color change was also produced in this stage. Concentrations of different amino acids decreased because of reaction with carbonyl compounds. A precipitation of potassium with tartaric acid was also observed.  相似文献   
620.
Chemical and Statistical Analysis of Precipitation in Singapore   总被引:1,自引:0,他引:1  
The results of chemical analyses of precipitation samples collected in Singapore between August 1997 and July 1998 are presented. Major inorganic and organic ions were determined in 169 rain samples collected using an automated wet-only sampler. The daily sample pH values ranged from 3.49 to 6.54 with a volume-weighted mean of 4.50, and about 88% of the samples had pH values less than 5.0 Nss-SO4 2? accounted for about 53 % of the sum of anions in rain, whereas chloride, nitrate, formate, and acetate accounted for the remainder. Rain chemistry data were analyzed using principal component analysis to find possible sources of the measured chemical species. Three components that accounted for 83.5% of the total variance were extracted: sea-spray (Na+, Cl? and and Mg2+) and soil particles (Ca2+ and K+), acid factor (nss-SO4 2?, NO3 ?, NH4 +, and H+), and biomass burning (HCOO? and CH3COOO?).  相似文献   
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