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21.
In climatology, maximum covariance analysis (MCA) is one of the most popular tools for investigating association between two multivariate variables across time and space. These association studies are important because many climate phenomena such as the El Niño-Southern Oscillation (ENSO) and the North Atlantic Oscillation are results of interaction between these variables. Despite its popularity, maximum covariance analysis does not provide straightforward statistical inference on its estimates and furthermore it does not provide an objective way to handle irregularly observed data, frequently encountered in climatology. The aim of this article is to describe a modelbased maximum covariance analysis that can accommodate irregularly observed data. The methodology combines maximum covariance analysis’s relationship with Tucker inter-battery factor analysis and the state-space methodology for missing data. The methodology is illustrated with an application to investigate association between Irish winter precipitation and global sea surface temperature (SST) anomalies.  相似文献   
22.
ABSTRACT:   Vertical profiles of water quality were surveyed before and after mass mortality of fish cultured in cages in Lake Cirata, a man made lake in Indonesia. The first survey was performed 4 months before the mass mortality and the second survey was carried out 4 days after the mass mortality. In the first survey, the conditions below 8 m depth were reductive and anoxic, although at 8 and 10 m depth, the water became oxidative in spite of low oxygen concentration in the second survey. These changes were probably caused by strong mixing of surface water with deeper water. Eight months after the mass mortality, when the redox potential at 8 m became reductive again, exposure tests of fish were performed in different layers in the water column around the cage. During the exposure tests the redox potential of the water was less than −100 mV and 93% of carp died within 6 h of exposure at 8 m depth. These results indicated that the mass mortality was caused by the strong mixing of surface water with reductive water in deeper layers.  相似文献   
23.
The postprandial increases in AA and insulin independently stimulate protein synthesis in skeletal muscle of piglets. Leucine is an important mediator of the response to AA. We have shown that the postprandial increase in leucine, but not isoleucine or valine, acutely stimulates muscle protein synthesis in piglets. Leucine increases muscle protein synthesis by modulating the activation of mammalian target of rapamycin (mTOR) complex 1 and signaling components of translation initiation. Leucine increases the phosphorylation of mTOR, 70-kDa ribosomal protein S6 kinase-1, eukaryotic initiation factor (eIF) 4E-binding protein-1, and eIF4G; decreases eIF2α phosphorylation; and increases the association of eIF4E with eIF4G. However, leucine does not affect the upstream activators of mTOR, that is, protein kinase B, adenosine monophosphate-activated protein kinase, and tuberous sclerosis complex 1/2, or the activation of translation elongation regulator, eukaryotic elongation factor 2. The action of leucine can be replicated by α-ketoisocaproate but not by norleucine. Interference by rapamycin with the raptor-mTOR interaction blocks leucine-induced muscle protein synthesis. The acute leucine-induced stimulation of muscle protein synthesis is not maintained for prolonged periods, despite continued activation of mTOR signaling, because circulating AA fall as they are utilized for protein synthesis. However, when circulating AA concentrations are maintained, the leucine-induced stimulation of muscle protein synthesis is maintained for prolonged periods. Thus, leucine acts as a nutrient signal to stimulate translation initiation, but whether this translates into a prolonged increase in protein synthesis depends on the sustained availability of all AA.  相似文献   
24.
Thrips are damaging pests in pepper worldwide. They can cause damage directly by feeding on leaves, fruits or flowers, and also indirectly by transferring viruses, especially tomato spotted wilt virus (TSWV). Although thrips are among the most damaging pests in pepper, until now there is no commercial variety with a useful level of resistance to thrips. This is at least partly due to the lack of knowledge on resistance levels in pepper germplasm of QTLs and/or genes for resistance, and of information about resistance mechanisms to thrips in pepper. This paper describes our research aimed at developing practical and reliable screening methods for thrips resistance in pepper and at identifying pepper accessions showing a strong resistance to thrips. Thirty-two pepper accessions from four species of pepper (Capsicum annuum, C. baccatum, C. chinense and C. frutescens) and two species of thrips (Frankliniella occidentalis and Thrips parvispinus) were used in this study. Our results indicate that the laboratory based leaf disc test and the detached leaf test can be used as reliable screening methods for thrips resistance in pepper. We observed a large variation for resistance to thrips in Capsicum that can be exploited in breeding programs.  相似文献   
25.
26.
This report examines the effectiveness of clindamycin for the treatment of babesiosis in dogs (n=10) experimentally infected with Babesia gibsoni (B. gibsoni). Clindamycin (25 mg/kg body weight, per os, q 12 hours for 14 days) gradually reduced parasitemia levels and induced morphological changes that indicated degeneration of parasites (e.g., segmentation; size reduction; localization in the cell limbic and/or torn state of the nucleus; and swelling, decrease, or disappearance of the cytoplasm) in the majority of dogs. Clindamycin treatment reduced the clinical symptoms characteristic of Babesia infection, including anemia, anorexia, and listlessness. Clindamycin might be useful as a medicine for treatment of B. gibsoni infection.  相似文献   
27.
One way to maximize potential income of smallholder tree farmers is to ensure high quality of planting material. In San Carlos City, Negros Occidental, the Philippines, great importance is placed on seedling quality because Energy Crop Plantations (ECPs) managed under a Short-Rotation Coppice (SRC) system will involve a single planting for several three-year coppices. High seedling quality requires superior seed provenances and seedling propagation methods. Throughout the establishment of the nursery facility, and the propagation of planting stock, data collection, reporting and database systems have been designed to capture relevant costs and technical information. Training has been provided to nursery personnel and labourers to enable them to operate the nursery and produce high quality seedlings. This paper reports a practical operational evaluation of all materials and procedures followed in nursery establishment and seedling production. Economies of scale in nursery operation are achieved at a production level of at least 90,000 seedlings per planting season of three months in the year. The production cost is estimated at PhP 3.57/seedling, excluding the cost of the nursery infrastructure and overheads. Cost comparison with decentralized or contracted nurseries shows little variation at a total cost of PhP 4.12/seedling. However, with these alternative nursery arrangements there is high risk of producing low quality seedlings by possible reduction of inputs and skipping quality enhancement procedures to reduce production cost.  相似文献   
28.
Journal of Crop Science and Biotechnology - The role of genetic diversity in crop germplasm is an important concept within genetic conservation. In this research, 43 accessions were analyzed at the...  相似文献   
29.
Hedgerows planted along the contour on steep lands in the humid tropics reduce soil erosion and build terraces over time. The objectives of this study in two Hapludoxes in the Philippines were to evaluate changes after 4 years in soil properties and soil water relations on transects perpendicular to the cropped alleys between four grass and tree hedgerow systems and a control. Hedgerow plants included Gliricidia sepium, Paspalum conjugatum, and Penisetum purpureum. Soil properties evaluated as a function of position in the alley (upper, middle, or lower elevation in an alley) included bulk density, mechanical impedance, soil water transmissivity, water retention, soil water pressure, and soil water content. In general, soil properties were not affected by hedgerow system, but were affected by position in the alley. Nearness to the hedgerow, but not hedgerow species, affected soil water distribution (P = 0.05). Plant available water at the 10–15 cm depth was 0.16 m3 m−3, 0.13 m3 m−3, and 0.08 m3 m−3 for the lower, middle, and upper alley position, respectively. Water transmissivity decreased from 0.49 mm s−1 in the lower alley to 0.12 mm s−1 in the upper alley. The lower soil water contents and soil water pressures in and near the hedgerows confirmed competition for water between the hedgerow species and the food crop in the alley, a condition that is expected to suppress food crop production.  相似文献   
30.
We examined the effects of phosphorus (P) fertilization on N2O emissions from an Acacia mangium plantation in Indonesia. We focused on the roles of microbial and plant root activities using a trenching method to prepare root-excluded and root-including plots. In root-excluded plots, P application did not change the amount of N2O emissions. By contrast, in root-including plots, P application significantly reduced N2O emissions (from 71.1?±?20.2 to 19.3?±?5.1 mg N m?2 106 days?1). Lower total P, Bray-2 P, and Bio-P (microbial P determined by chloroform fumigation extraction method) contents in the soils of root-including plots as compared to root-excluded plots a few days after P application shows that acacia trees absorbed P fertilizer rapidly. This rapid P uptake probably relieved the P limitation of acacia and might have consistently increased root N uptake. This interpretation is supported by lower inorganic N content in P-applied soils (the average of three sampling times is 8.9 and 11.3 μg N g soil?1 in P-applied soils and soils without P application, respectively), which in turn decreased N2O emissions. Our study suggests that P fertilizer suppresses N2O emissions from tropical leguminous forest plantations.  相似文献   
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