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The classification of cereals using near‐infrared Fourier transform Raman (NIR‐FT/Raman) spectroscopy was accomplished. Cereal‐based food samples (n = 120) were utilized in the study. Ground samples were scanned in low‐iron NMR tubes with a 1064 nm (NIR) excitation laser using 500 mW of power. Raman scatter was collected using a Ge (LN2) detector over the Raman shift range of 202.45~3399.89 cm‐1. Samples were classified based on their primary nutritional components (total dietary fiber [TDF], fat, protein, and sugar) using principle component analysis (PCA) to extract the main information. Samples were classified according to high and low content of each component using the spectral variables. Both soft independent modeling of class analogy (SIMCA) and partial least squares (PLS) regression based classification were investigated to determine which technique was the most appropriate. PCA results suggested that the classification of a target component is subject to interference by other components in cereal. The Raman shifts that were most responsible for classification of each component were 1600~1630 cm‐1 for TDF, 1440 and 2853 cm‐1 for fat, 2910 and 1660 cm‐1 for protein, and 401 and 848 cm‐1 for sugar. The use of the selected spectral region (frequency region) for each component produced better results than the use of the entire region in both SIMCA and PLS‐based classifications. PLS‐based classification performed better than SIMCA for all four components, resulting in correct classification of samples 85~95% of the time. NIR‐FT/Raman spectroscopy represents a rapid and reliable method by which to classify cereal foods based on their nutritional components.  相似文献   
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Ohne Zusammenfassung  相似文献   
65.
After intramammary infection, polymorphonuclear neutrophil leukocytes (PMN) are the first cells recruited into the mammary gland. Rapid recruitment of and bacterial phagocytosis and killing by PMN are the most effective defenses against establishment of bacterial infection. In addition to their phagocytic and bactericidal properties, PMN may play a key supportive role through secretion of cytokines during the innate immune response. We sought to determine whether bovine PMN produce cytokines in response to stimulation by lipopolysaccharide (LPS). To investigate the effects of LPS on the expression of cytokines secreted by bovine PMN, we measured the expression of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-12, and interferon (IFN)-gamma by ELISA after stimulation with different concentrations of LPS, and secretion of IL-8 after co-stimulation with LPS and either TNF-alpha or IL-1beta. Bovine PMN were shown to secrete TNF-alpha , IL-1beta, IL-12, IL-8 and IFN-gamma in response to LPS. Co-incubation of PMN with LPS and TNF-alpha increased secretion of IL-8 when compared to LPS alone. It was concluded that LPS stimulation up-regulates the secretion of cytokines by bovine PMN, and that co-incubation of LPS with TNF-alpha had an additive effect on the secretion of IL-8. These data show that bovine PMN, in addition to their phagocytic and bactericidal properties, may play a supportive role in the innate immune response to infection by Gram-negative bacteria through their ability to produce immuno-regulating cytokines.  相似文献   
66.
Lysophospholipase D (lysoPLD), generating lipid mediator lysophosphatidic acid (LPA) from lysophosphatidyclcholine (LPC), is known to be inhibited by lysophosphatidic acids. Meanwhile, some plant lipids are known to contain lysophospholipids as minor components. Therefore, it is interesting to test whether edible seed samples, rich in phospholipids, may contain lysophospholipids, which express a strong inhibition of lysoPLD activity. First, the structural importance of fatty acyl group in LPAs was examined by determining the inhibitory effect of various LPAs on bovine lysoPLD activity. The most potent in the inhibition of lysoPLD activity was linoleoyl-LPA ( K i, 0.21 microM), followed by arachidonoyl-LPA ( K i, 0.55 microM), oleoyl-LPA ( K i, 1.2 microM), and palmitoyl-LPA ( K i, 1.4 microM), based on the fluoresecent assay. The same order of inhibitory potency among LPA analogs with different acyl chains was also found in the spectrophotometric assay. Subsequently, the extracts of 12 edible seeds were screened for the inhibition of lysoPLD activity using both spectrophotometric and fluorescent assays. Among seed extracts tested, the extract from soybean seed, sesame seed, or sunflower seed (30 mg seed weight/mL) was found to exhibit a potent inhibition (>80%) of lysoPLD activity. In further study employing ESI-MS/MS analysis, major LPA components in seed extracts were identified to be 1-linoleoyl LPA, 1-oleoyl LPA, and 1-palmitoyl LPA with 1-linoleoyl LPA being more predominant. Thus, the potent inhibition of lysoPLD activity by seed extracts might be ascribed to the presence of LPA with linoleoyl group rather than other acyl chains.  相似文献   
67.
Endosulfan, an endocrine disrupting chemical, is a widely used cyclodiene organochlorine pesticide worldwide, and it blocks neuronal GABA(A)-gated chloride channels in mammals and aquatic organisms. Endosulfan and its metabolites, such as endosulfan sulfate, are persistent in environments and are considered as toxic chemicals. For bioremediation of endosulfan, in this study, an attempt was made to isolate an endosulfan and endosulfan sulfate degrading bacterium from endosulfan-polluted agricultural soil. Through repetitive enrichment and successive subculture using endosulfan or endosulfan sulfate as the sole carbon source, a bacterium KS-2P was isolated. The KS-2P was identified as Pseudomonas sp. on the basis of the results of a 16S rDNA sequencing analysis and MIDI test. The degradation ratios for endosulfan or endosulfan sulfate in minimal medium containing endosulfan (23.5 microg mL(-1)) or endosulfan sulfate (21 microg mL(-1)) were 52% and 71%, respectively. Our results suggest that Pseudomonas sp. KS-2P has potential as a biocatalyst for endosulfan bioremediation.  相似文献   
68.
Pericarp thickness and ear traits are important selection criteria for breeding fresh market waxy corn. This research was conducted to better understand genetic control of these traits in popular South Korean germplasm now grown in Illinois. Pericarp thickness on five kernel regions, and ten inflorescence architecture traits were measured on ears from 264 F2:3 families from a cross between Korean inbreds BH20 and BH30. All five pericarp thickness traits showed high heritabilities and were highly correlated. Multivariate principal components analysis (PCA) revealed that just one principal component (PC) explained most of the total phenotypic variation. A number of univariate quantitative trait loci (QTL) were detected and most were associated with more than one kernel pericarp region. Four out of seven PC-QTL were located in chromosome positions where three or more pericarp thickness univariate QTL were detected. Conversely, three PC-QTL were found in regions with just a single or two univariate QTL, indicating that these QTL regions may be more important for overall pericarp thickness than suggested by univariate analysis. The PCA, QTL, and PC-QTL results indicate that pericarp thickness on different kernel regions may be controlled by common genes with pleiotropic effects. Additive effects of QTL for thinner pericarp thickness came from both BH20 and BH30. For ear architecture traits, heritability varied from 0.38 to 0.72, and several traits were correlated. The PCA reduced these traits into three independent PCs, and all substantial component traits for these PCs were also significantly correlated. A number of univariate QTL were clustered closely, and some PC-QTL were detected in these regions. Some PC-QTL were found in chromosome regions where univariate QTL were not detected, again suggesting that these regions may have larger overall effects on ear architecture than suggested by univariate analyses. Collectively, these QTL may be useful for marker assisted introgression into germplasm more adapted to the U.S.  相似文献   
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This report deals with the acute onset of an abortion outbreak and high sow mortality in one pig herd consisted of 1,200 pigs and 120 sows on Jeju Island, Korea. Affected pregnant sows showed clinical signs, including high fever, gradual anorexia, vomiting, depression, recumbency, prostration, abortion, and a few deaths. Four dead sows, five aborted fetuses from the same litter, and 17 sera collected from sows infected or normal were submitted to the Pathology Division of the National Veterinary Research and Quarantine Service for diagnostic investigation. Grossly, hepatomegaly and splenomegaly were observed in sows. Multiple necrotic foci were scattered in the lungs, liver, spleen, and lymph nodes. Microscopically, multifocal necrotizing lesions and protozoan tachyzoites were present in the lesions. Tachyzoites of Toxoplasma (T.) gondii were detected immunohistochemically. Latex agglutination showed that the sera of 7 of 17 (41.2%) sows were positive for antibody to T. gondii. The disease outbreak in this herd was diagnosed as epizootic toxoplasmosis. To our knowledge, this is the first report of porcine toxoplasmosis with a high abortion rate and sow mortality in Korea.  相似文献   
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