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In the present study, the use of dogs with experimental autoimmune encephalomyelitis (EAE) as a disease model for necrotizing encephalitis (NE) was assessed. Twelve healthy dogs were included in this study. Canine forebrain tissues (8 g), including white and grey matter, were homogenized with 4 mL of phosphate-buffered saline for 5 min in an ice bath. The suspension was emulsified with the same volume of Freund''s complete adjuvant containing 1 mg/mL of killed Mycobacterium tuberculosis H37Ra. Under sedation, each dog was injected subcutaneously with canine brain homogenate at four sites: two in the inguinal and two in the axillary regions. A second injection (booster) was administered to all the dogs using the same procedure 7 days after the first injection. Clinical assessment, magnetic resonance imaging, cerebrospinal fluid analyses, necropsies, and histopathological and immunohistochemical examinations were performed for the dogs with EAE. Out of the 12 animals, seven (58%) developed clinically manifest EAE at various times after immunization. Characteristics of canine EAE models were very similar to canine NE, suggesting that canine EAE can be a disease model for NE in dogs.  相似文献   
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We measured vertical and horizontal variation in canopy transmittance of photosynthetically active radiation in five Pseudotsuga menziesii (Mirb.) Franco-Tsuga heterophylla (Raf.) Sarg. (Douglas-fir-western hemlock) stands in the central Cascades of southern Washington to determine how stand structure and age affect the forest light environment. The shape of the mean transmittance profile was related to stand height, but height of mean maximum transmittance was progressively lower than maximum tree height in older stands. The vertical rate of attenuation declined with stand age in both the overstory and understory. A classification of vertical light zones based on the mean and variance of transmittance showed a progressive widening of the bright (low variance and high mean) and transition (high variance and rapid vertical change) zones in older stands, whereas the dim zone (low variance and mean) narrowed. The zone of maximum canopy surface area in height profiles, estimated by inversion of transmittance profiles, changed from relatively high in the canopy in most young stands ("top-heavy") to lower in the canopy in older stands ("bottom-heavy"). In the understory, all stands had similar mean transmittances, but the spatial scale of variation increased with stand age and increasing crown size. The angular distribution of openness was similar in all stands, though the older stands were less open at all angles than the younger stands. Understory openness was generally unrelated to transmittance in the canopy above. Whole-canopy leaf area indices, estimated using three methods of inverting light measurements, showed little correspondence across methods. The observed patterns in light environment are consistent with structural changes occurring during stand development, particularly the diversification of crowns, the creation of openings of various sizes and the elaboration of the outer canopy surface. The ensemble of measurements has potential use in distinguishing forests of differing ages that have similar stature.  相似文献   
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Principal component analysis (PCA) and multiple linear regression (MLR) were conducted to characterize the drying of sea cucumber (SC). Far infrared radiation drying (FIRD) and hot air drying (AD) were used to dehydrate SC. Thirteen variables—including the morphological, color, and textural properties of dried SC—were selected for statistical analysis. The analysis of these 13 variables yielded three principal components showing significant correlations. PCA showed that the first three components represented 86.2% of the total variation. The first principal component was primarily related to the morphological properties of SC. The principal components determined by the PCA were more strongly influenced by the morphological variables than by the drying method. Of the morphological variables, the weight of SC had the strongest influence on the drying time and rehydration ratio of FIRD and AD.  相似文献   
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Genome-wide association studies (GWAS) are useful to facilitate crop improvement via enhanced knowledge of marker-trait associations (MTA). A GWAS for grain yield (GY), yield components, and agronomic traits was conducted using a diverse panel of 239 soft red winter wheat (Triticum aestivum) genotypes evaluated across two growing seasons and eight site-years. Analysis of variance showed significant environment, genotype, and genotype-by-environment effects for GY and yield components. Narrow sense heritability of GY (h 2  = 0.48) was moderate compared to other traits including plant height (h 2  = 0.81) and kernel weight (h 2  = 0.77). There were 112 significant MTA (p < 0.0005) detected for eight measured traits using compressed mixed linear models and 5715 single nucleotide polymorphism markers. MTA for GY and agronomic traits coincided with previously reported QTL for winter and spring wheat. Highly significant MTA for GY showed an overall negative allelic effect for the minor allele, indicating selection against these alleles by breeders. Markers associated with multiple traits observed on chromosomes 1A, 2D, 3B, and 4B with positive minor effects serve as potential targets for marker assisted breeding to select for improvement of GY and related traits. Following marker validation, these multi-trait loci have the potential to be utilized for MAS to improve GY and adaptation of soft red winter wheat.  相似文献   
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4(5)-Methylimidazole has received the attention of federal and state regulatory agencies because of its carcinogenicity and common presence in foods and beverages. In the present study, the formation of 4(5)-methylimidazole in Maillard reaction model systems consisting of D-glucose/NH(3), L-rhamnose/NH(3), methylglyoxal/NH(3), and methylglyoxal/formaldehyde/NH(3) was investigated. 4(5)-Methylimidazole was formed at levels ranging from 0.49 to 0.71 mg/mL in the d-glucose/NH(3) model system. The formation of 4(5)-methylimidazole was slightly higher in the L-rhamnose/NH(3) system (0.91 mg/mL) than in the d-glucose/NH(3) system (0.71 mg/mL) under the conditions used in the present study. A methylglyoxal/NH(3) system produced significantly higher levels of 4(5)-methylimidazole (5.70 mg/mL), suggesting that methylglyoxal is an important precursor of 4(5)-methylimidazole. Ammonolysis of methylglyoxal, which is one of the glucose degradation products, was proposed to form formamide, which subsequently reacted with 2-aminopropanal (α-aminocarbonyl intermediate) formed from methylglyoxal to give 4- or 5-methylimidazole. The levels of 4(5)-methylimidazole found in commercial cola soft drinks range from 0.30 μg/mL (brand 3) to 0.36 μg/mL (brands 1 and 5).  相似文献   
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The correct identification of the geographical origin of deer antlers is essential to quality control, as its positive physiological effects correlate with chemical components. In this study, we applied both genomics and metabolomics to the origin-identification of 101 samples from Canada, New Zealand, and Korea. The genomics identified deer species in each country but failed to categorize all the samples, due to the presence of identical species in different countries. For identical species, NMR-based metabolomics gave clean separations, compounds specific to each country were identified, and the validity was confirmed by prediction analysis. As the genomics provided unambiguous read-outs for different species, and the metabolomics cleanly distinguished among identical species from different countries, their combined use could be a robust method for origin-identification even in difficult cases. We believe the method to be generally applicable to many herbal medicinal products for which various species are grown internationally.  相似文献   
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The in vivo metabolism of a new herbicide pyribenzoxim (benzophenone Ο-[2,6-bis(4,6-dimethoxypyrimidin-2-yloxy)benzoyl]oxime) in rice was carried out using container trials. Two radiolabeled forms of [carbonyl-(14)C]pyribenzoxim (P1) and [ring-(14)C(U)]pyribenzoxim (P2) were treated separately as formulations for foliar treatment by single applications of 50 g of active ingredient (ai)/ha at the 4-6 leaves stage. At 0, 7, 30, and 60 days after treatment (DAT), samples of panicle, foliage/rest of plant, and roots were taken for analysis. Upon harvest (120 DAT), rice plants were separated into grain, husk, straw, and root parts. Total radioactive residues (TRRs) at each sampling date were determined to show that the final radioactive residues at harvest were low in grain, husk, straw, and roots, accounting for <17 ppb. The concentration of final residues in the rice plant decreased rapidly, and less than 0.1% of initial TRRs remained at harvest. At 7 DAT, metabolite 1 [M1, 2,6-bis(4,6-dimethoxypyrimidin-2-yloxy)benzoic acid] and two unknown compounds (other-1 and other-2) were detected in foliage extract, accounting for 3.5% TRRs (21.0 ppb), 3.1% TRRs (19.0 ppb), and 9.0% TRRs (54.3 ppb), respectively, while 26.1% of M1 was observed in solvent wash. Any other metabolites were not detected in the plant, including expected metabolite M3 (benzophenone oxime). On the basis of the results obtained, a metabolic pathway of pyribenzoxim in a rice plant was proposed.  相似文献   
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