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1.
A measure to evaluate performance in irrigation systems is analyzed using the mean square prediction error concept. In the context of irrigation system management, the term error means the deviation of actual performance from a reference performance. The measure assesses performance in terms of the management objectives of adequacy and dependability of water delivery and an equitable distribution among various water users. It provides an understanding of the management capacity to schedule and distribute water in an irrigation system. Application of the performance measure is demonstrated by evaluating performance of an irrigation system in the Northwest Frontier Province of Pakistan.  相似文献   
2.
AIM: To determine the function of peritoneal mesothelial cells on the inflammatory microenvironment by administration of endometrial cells,and further define the pathogenesis of endometriosis.METHODS: Homogenous mouse endometrial epithelial and stromal cells were injected into the peritoneal cavities of Swiss Webster mice.After 4,24,and 72 h,a number of endpoints evaluated: protein concentrations of cytokine MCP-1,IL-1 α,IL-6 in peritoneal lavage and gene expressions of MCP-1,IL-1 α,IL-6 in peritoneal mesothelial cells and macrophages.RESULTS: The intraperitoneal administration of endometrial cells increased the protein expressions of cytokines in the peritoneal lavage of the recipient mice,which increased at 4-hour points and subsequently decreased with time.Gene expressions of cytokines in peritoneal mesothelial cells paralleled with the protein quantities in peritoneal lavage.The peak time of gene expression of cytokines in peritoneal macrophages was at the 24-hour point.The endometrial epithelial cells stimulated stronger inflammatory responses in the peritoneal cavity than the endometrial stromal cells.CONCLUSION: The recipient mice have a non-specific inflammatory response to the presence of endometrial cells in the peritoneal cavity.Mesothelial cells may be the targets of early inflammatory stress initiated in the presence of endometrial cells.  相似文献   
3.
Photoperiod and temperature modulated the seasonal pattern of ovarian gene expression of P450 aromatase, Follicle-Stimulating Hormone receptor and Luteinizing Hormone receptor in Atlantic salmon broodstock.  相似文献   
4.
The current study is based on the screening of novel insecticides from new sources that have not being exploited hitherto. The major objectives of this research work were to extract marine molluscs, Lambis lambis, Trochus radiatus and Chicoreus ramosus, from Tuticorin coastal waters using different solvents to test their insecticidal properties and partially purify the active components. The ethyl acetate extracts of L. lambis and T. radiatus showed 100% mortality of Sitophilus oryzae, at a concentration of 200 μg ml−1. The LC50 values for ethyl acetate extracts of L. lambis, T. radiatus and C. ramosus were found to be 67.08, 348.86 and 571.42 μg ml−1, respectively. With regard to bacterial metabolites, at a concentration of 200 μg ml−1 the ethyl acetate extract of A3 was able to elicit an activity of 40% and that of strain A1 – 20%. The LC50 values of the bacterial metabolites were also investigated. Upon chromatographic separation of active ethyl acetate extracts of T. radiatus, the 100% methanol column-purified fraction was found to have an activity of 30% at a concentration of 10 μg against S. oryzae. The purity of the partially pure active compound was observed to be 72.78% on analysis with high pressure thin layer chromatography.  相似文献   
5.
Combined effects of beta-glucan and lipopolysaccharide (LPS) on survival and immune response were studied in Cyprinus carpio that were challenged with the pathogen Aeromonas hydrophila. beta-Glucan from Saccharomyces cervisiae and LPS from a virulent strain of A. hydrophila were used in this study. Different concentrations of beta-glucan+LPS mixture were administered on days 1, 7, and 14 through different routes (intraperitoneal injection, bathing, and oral administration). Control and test fish were challenged by intraperitoneal injection of LD50 concentration of A. hydrophila on day 16 and subsequently, mortality and relative percent survival (RPS) were recorded. Intraperitoneal injection elicited 100% RPS even at the lowest concentration (100 microg beta-glucan+10 microg LPS); whereas, oral administration improved RPS rate of carps at higher concentration (1% beta-glucan+0.25% LPS). Bathing did not improve the RPS. Test animals injected with even the minimum dose of the immunomodulators (100 microg beta-glucan+10 microg LPS/fish) had a significant increase in total blood leukocyte counts and an increase in the proportion of neutrophils and monocytes. Superoxide anion production by macrophages was also elevated, which presumably aided the efficient killing of bacterial pathogen. Lower concentration of beta-glucan+LPS had an adjuvant effect on antibody production as pretreatment by injection of 100 microg beta-glucan+10 microg LPS/fish resulted in higher antibody titer against A. hydrophila following vaccination. RT-PCR analyses showed that the expression of interleukin-1beta mRNA did not increase in test fish when compared with the control. Classical and alternative complement pathways were not affected by either the dose or the route of administration of the compounds. It may be concluded that intraperitoneal injection and oral administration, and not the bathing, of beta-glucan+LPS mixture in carp could enhance resistance to challenge by A. hydrophila through changes in several non-specific and specific immune responses.  相似文献   
6.
The present study was on assessment of the anti-parasitic activities of nickel nanoparticles (Ni NPs) against the larvae of cattle ticks Rhipicephalus (Boophilus) microplus and Hyalomma anatolicum (a.) anatolicum (Acari: Ixodidae), fourth instar larvae of Anopheles subpictus, Culex quinquefasciatus and Culex gelidus (Diptera: Culicidae). The metallic Ni NPs were synthesized by polyol process from Ni-hydrazine as precursor and Tween 80 as both the medium and the stabilizing reagent. The synthesized Ni NPs were characterized by Fourier transform infrared (FTIR) spectroscopy analysis which indicated the presence of Ni NPs. Synthesized Ni NPs showed the X-ray diffraction (XRD) peaks at 42.76°, 53.40°, and 76.44°, identified as 1 1 1, 2 2 0, and 2 0 0 reflections, respectively. Scanning electron microscopy (SEM) analysis of the synthesized Ni NPs clearly showed that the Ni NPs were spherical in shape with an average size of 150 nm. The Ni NPs showed maximum activity against the larvae of R. (B.) microplus, H. a. anatolicum, A. subpictus, C. quinquefasciatus and C. gelidus with LC50 values of 10.17, 10.81, 4.93, 5.56 and 4.94 mg/L; r2 values of 0.990, 0.993, 0.992, 0.950 and 0.988 and the efficacy of Ni-hydrazine complexes showed the LC50 values of 20.35, 22.72, 8.29, 9.69 and 7.83 mg/L; r2 values of 0.988, 0.986, 0.989, 0.944 and 0.978, respectively. The findings revealed that synthesized Ni NPs possess excellent larvicidal parasitic activity. To the best of our knowledge, this is the first report on larvicidal activity of blood feeding parasites using synthesized Ni NPs.  相似文献   
7.
This paper analyses the water management performance of small holder irrigation systems in Zimbabwe. The government and farmer managed systems are compared in terms of their ability to match desired with actual water supply. Desired supply is defined as crop water requirements adjusted downwards by rainfall where relevant. The Theil measure of accuracy of forecasts is used to calculate the error committed by each system in trying to match water supply and demand. The analysis shows that, everything else being equal, the farmer managed system performs better than the government system in matching supply and demand. This means that the farmer managed systems should be encouraged for future small holder irrigation development in Zimbabwe.  相似文献   
8.
Polymerase chain reaction/electrospray ionization-mass spectrometry (PCR/ESI-MS, previously known as "TIGER") utilizes PCR with broad-range primers to amplify products from a wide array of organisms within a taxonomic group, followed by analysis of PCR amplicons using mass spectrometry. Computer analysis of precise masses allows for calculations of base compositions for the broad-range PCR products, which can then be compared to a database for identification. PCR/ESI-MS has the benefits of PCR in sensitivity and high-throughput capacity, but also has the distinct advantage of being able to detect and identify organisms with no prior characterization or sequence data. Existing broad range PCR primers, designed with an emphasis on human pathogens, were tested for their ability to amplify DNA of well characterized phytobacterial strains, as well as to populate the existing PCR/ESI-MS bacterial database with base counts. In a blinded panel study, PCR/ESI-MS successfully identified 93% of unknown bacterial DNAs to the genus level and 73% to the species/subspecies level. Additionally, PCR/ESI-MS was capable of detecting and identifying multiple bacteria within the same sample. The sensitivity of PCR/ESI-MS was consistent with other PCR based assays, and the specificity varied depending on the bacterial species. Preliminary tests with real life samples demonstrate a high potential for using PCR/ESI-MS systems for agricultural diagnostic applications.  相似文献   
9.
The phenolic compounds and flavonoids were determined from the extracts of Withania somnifera root (WSREt) and leaf (WSLEt). The WSREt has 28.26 mg/g total phenolic compounds and 17.32 mg/g flavonoids, whereas WSLEt has 5.4 mg/g total phenolic compounds and 5.1 mg/g flavonoids. The WSREt, WSLEt and glibenclamide were orally administered daily to diabetic rats for 8 weeks. After the treatment, the levels of urine sugar, blood glucose, liver glycogen, and antioxidants like vitamin C and E in plasma and superoxide dismutase (SOD), catalase (CAT), thiobarbituric acid reactive substances (TBARS), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and reduced glutathione (GSH) in liver, kidney and heart were determined. Diabetic rats showed a significant (p < 0.05) elevation in glucose and TBARS and a significant (p < 0.05) reduction in glycogen, vitamin C and E, SOD, CAT, GPx, GST, and GSH levels when compared to normal control rats. Administration of WSREt, WSLEt and glibenclamide to diabetic rats restored the levels to normal. In the light of aforesaid facts, it is suggested that the presence of phenolic compounds including flavonoids in W. somnifera root and leaf extracts and their antioxidant activity may play a vital role in reduction of blood glucose level in alloxan-induced diabetic rats.  相似文献   
10.
Brassica oleracea L. includes various types of important vegetables that show extremely diverse phenotypes. To elucidate the genetic diversity and relationships among commercial cultivars derived by different companies throughout the world, we characterized the diversity and genetic structure of 91 commercial B. oleracea cultivars belonging to six varietal groups, including cabbage, broccoli, cauliflower, kohlrabi, kale and kai-lan. We used 69 polymorphic microsatellite markers showing a total of 359 alleles with an average number of 5.20 alleles per locus. Polymorphism information content (PIC) values ranged from 0.06 to 0.73, with an average of 0.40. Among the six varietal groups, kohlrabi cultivars exhibited the highest heterozygosity level, whereas kale cultivars showed the lowest. Based on genetic similarity values, an UPGMA clustering dendrogram and a two-dimensional scale diagram (PCoA) were generated to analyze genetic diversity. The cultivars were clearly separated into six different clusters with a tendency to cluster into varietal groups. Model-based structure analysis revealed six genetic groups, in which cabbage cultivars were divided into two subgroups that were differentiated by their head shape, whereas cauliflower and kai-lan cultivars clustered together into a single group. Furthermore, we identified 18 SSR markers showing 27 unique alleles specific to only one cultivar that can be used to discriminate 22 cultivars from the others. Our phylogenetic and population structure analysis presents new insights into the genetic structure and relationships among 91 B. oleracea cultivars and provides valuable information for breeding of B. oleracea species. In addition, we demonstrate the utility of SSR markers as a powerful tool for discriminating between the cultivars. The SSR markers described herein will also be helpful for Distinctness, Uniformity and Stability (DUS) test of new cultivars.  相似文献   
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