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101.
A flow cytometric technique was used to detect apoptosis and necrosis of bovine polymorphonuclear neutrophil leukocytes (PMN) using fluorescein isothiocyanate labeled annexin-V and propidium iodide (PI). Isolation of PMN from the blood following lysis by water or NH4Cl resulted in false positive results for apoptosis. Therefore, a method was developed to identify living, apoptotic and necrotic PMN simultaneously in a single 100 microl blood sample. To establish a positive control for PMN apoptosis, the effect of cycloheximide, actinomycin D, diamide, buthionine sulfoximine and sodium arsenite, that have been described to induce apoptosis by various mechanisms was tested. Only actinomycin D induced a significant increase in the percentage of apoptotic PMN after 2 h. Incubation of blood for 6 h with cycloheximide, actinomycin D and buthionine sulfoximine resulted in a significant increase of apoptotic PMN compared to control values. Sodium arsenite, mainly caused necrosis after 6 h of incubation.  相似文献   
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103.
In this paper, detailed simulation of human hair bleaching was conducted. The materials and chemical used as well as the hair bleaching procedures were described. After bleaching, the colour change of the hair was evaluated in accordance with CIE Lab system and the hair bleaching results was analysed. Following the hair bleaching process, hair coloration was employed with the use of colour boosting shampoo with henna of three different colours. The effect of different bleached hair samples on colour uptake property was examined by spectrophotometer method. Based on this study, it was concluded that the original hair colour did affect the colour uptake using the colour boosting shampoo with henna significantly. In order to have a visible coloring result, hair bleaching treatment was therefore highly recommended before conducting the hair coloration process.  相似文献   
104.
The pattern of Cylindrocladium pteridis adhesion, germination and penetration in eucalypt leaves was assessed using scanning electron microscopy. The effects of inoculum concentration, leaf wetness period, plant age and branch position of cylindrocladium leaf blight and defoliation severity were assessed in greenhouse studies using two Eucalyptus grandis × E. urophylla hybrid clones. Penetration occurred through stomata, and there was no difference in the number of penetrations between young and old leaves. Percentage leaf area with lesions and defoliation increased with the increase in inoculum concentration (1 × 102 to 105 conidia mL−1), duration of leaf wetness period (6 to 48 h) and plant age (60 to 180 days). Branch position in plants also significantly affected the percentage leaf area with lesions and defoliation, the latter variable being significantly higher at the stem base. The highest values of lesion area were also observed on leaves at the stem base in both clones. The Pearson correlation between defoliation and leaf area with lesions was significant in all experiments ( r  > 0·9) indicating a high association between these two variables.  相似文献   
105.
106.
An ELISA test was developed to measure the levels of IgG antibody in specific-pathogen-free (SPF) cats immunised with two doses of an attenuated feline calicivirus (FCV) vaccine. All eight vaccinates were protected from virus challenge, but four out of five non-vaccinates were not. There was a significant difference in respect of protection from virus challenge between SPF cats with and without three-fold or greater increase in antibody units (P = 0.01). Each serum absorbance was standardised against the reference positive which has an arbitrary value of 100 antibody units. In SPF cats, the 99% confidence level for seropositivity to FCV was determined as greater than or equal to 2.5 antibody units. The results suggest that the sensitive ELISA test can be used to monitor the antibody status of SPF cat colonies prior to FCV vaccine trials, and to measure the immunogenicity of attenuated FCV vaccines. Thus, the ELISA test may replace the need for virus challenge, with consequent reduction in animals used in future FCV vaccine trials.  相似文献   
107.
A study was conducted to evaluate the performance of a nucleic acid sequence-based amplification (NASBA) assay for the detection of foot-and-mouth disease virus (FMDV). Two detection methods: NASBA-electrochemiluminescence (NASBA-ECL) and a newly developed NASBA-enzyme-linked oligonucleotide capture (NASBA-EOC) were evaluated. The diagnostic sensitivity of these assays was compared with other laboratory-based methods using 200 clinical samples collected from different regions of the world. Assay specificity was also assessed using samples (n=43) of other viruses that cause vesicular disease in livestock and genetic relatives of FMDV. Concordant results were generated for 174/200 (87.0%) of suspect FMD samples between NASBA-ECL and real-time RT-PCR. In comparison with the virus isolation (VI) data, the sensitivity of the NASBA-ECL assay was 92.9%, which was almost identical to that of the real-time RT-PCR (92.4%) for the same set of samples. There was broad agreement between the results of the NASBA-ECL and the simpler NASBA-EOC detection method for 97.1% of samples. In conclusion, this study provides further data to support the use of NASBA as a rapid and sensitive diagnostic method for the detection and surveillance of FMDV.  相似文献   
108.
PrP(c) (cellular prion protein, CD230) expression by subpopulations of lymphoid cells has been widely investigated in a variety of species, possibly because of the possible link between transmissible spongiform encephalopathies (TSE) transmission and blood transfusion. However, the role of the immune cells in the transmission of the disease is still unclear. Here we describe the optimisation and standardisation of a three-colour staining procedure to detect PrP in association with phenotypic and activation markers in ovine immune cells. We demonstrate a reproducible, flexible and sensitive method and that the combination of isotype-specific antibodies and Fab fragments is feasible. To our knowledge, this is the first report of such labelling of ovine cells. Using this method, we were able to detect differences in levels of PrP expression between blood and lymph node cells of the same animal, and considerable variability between animals. Moreover, we were able to explore possible associations between PrP expression and cellular activation and to identify cell subsets with different labelling patterns. We are currently employing this approach to evaluate variations in immunological parameters during experimental infection in sheep.  相似文献   
109.
The objectives of this study were to isolate and characterize vitellogenin from plasma of estradiol-treated protandrous black porgy,Acanthopagrus schlegeli. Vitellogenin concentrations in plasma measured by a validated enzyme-linked immunosorbent assay (ELISA) were also compared. Two-year-old black porgy (n=20) were fed with estradiol-17 (4 mg kg–1 of feed). Plasma was collected for purification of vitellogenin. Two forms of vitellogenin were found in plasma after chromatography on Sepharose CL-2B column and hydroxylapatite, and polyacrylamide gel electrophoresis. Black porgy vitellogenins are phospho-lipo-glycoproteins based on their chemical staining properties. The apparent molecular weights of the two forms of vitellogenin were 636 kDa and 321 kDa, respectively. The amino acid composition of purified vitellogenin was also analyzed after acid hydrolysis. The presence of immunoreactive vitellogenin was identified in the plasma and mucus extract from control and estradiol-induced females on the basis of Western blotting. Serial dilution of the plasma and mucus extract taken from estradiol-induced black porgy showed reactivity to an antiserum against lipovitellin in the ELISA, whereas mucus extract and plasma from male fish did not. Significantly higher concentrations of plasma vitellogenin were detected in estradiol-stimulated black porgy than in the control males.  相似文献   
110.
Unconscious motivation in humans is often inferred but rarely demonstrated empirically. We imaged motivational processes, implemented in a paradigm that varied the amount and reportability of monetary rewards for which subjects exerted physical effort. We show that, even when subjects cannot report how much money is at stake, they nevertheless deploy more force for higher amounts. Such a motivational effect is underpinned by engagement of a specific basal forebrain region. Our findings thus reveal this region as a key node in brain circuitry that enables expected rewards to energize behavior, without the need for the subjects;awareness.  相似文献   
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