排序方式： 共有7条查询结果，搜索用时 15 毫秒
1
1.
2.
Vegetable growers’ knowledge of pest and their control method was assessed in 2014 in East Shewa zone, Ethiopia. Vegetable growers were well aware of key pests of vegetables, although some of them did not consider pests as constraint to vegetable production. All respondents scouted their vegetables for pests and used presence or absence of pest as criterion for spraying. About 76% of the respondents read pesticide label before buying pesticides, while the rest 24% of the respondents did not read pesticide labels. All vegetable growers sprayed insecticide, whereas fungicides and herbicides were applied by 90% and 7% of the respondents, respectively. About 72% of the respondents washed their sprayer after each application day and discharged the washings onto the soil. Moreover, the majority (62%) of the respondents threw empty pesticide containers around the field. Also, it was found that 71% of the respondents did not use personal protective equipment (PPE) while spraying pesticides, but a few used one or two types of PPE. More than half of the respondents sprayed pesticides on mature crops and sold the produce within three to five days. 相似文献
3.
Mi-Hyun Hwang Dereje Damte Min-Hee Cho Young-Hoan Kim Seung-Chun Park 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(4):327-332
Composition of culture medium for mass production of Mycoplasma hyopneumoniae was optimized using a response surface methodology (RSM). Initially, the influence of glucose, thallium acetate, fresh yeast extract, horse serum, and porcine serum on the production of mycoplasmal protein was assessed using a ''one factor at a time'' technique. Next, factors with a significant effect, including fresh yeast extract, and horse and porcine sera, were selected for further optimization using a central composite design (CCD) of RSM. The experimental results were fitted into a second order polynomial model equation. Estimated optimal condition of the factors for maximum production of mycoplasmal protein (i.e., triple-fold increase from 0.8 mg/L produced by basal mycoplasma media to 2.5 mg/L) was 10.9% fresh yeast extract, 15% horse serum, and 31.5% porcine serum (v/v). For the optimized conditions, a 2.96 mg/L experimental result was observed, similar to the estimated optimal conditions result of the CCD. 相似文献
4.
The antibacterial activity, selection of Escherichia coli (E. coli) mutants and mechanisms of fluoroquinolone resistance were investigated by integrating the minimum inhibitory concentration (MIC), mutant prevention concentration (MPC) and in vitro dynamic model approaches. Difloxacin and orbifloxacin, for which the above information has been scarce, were used. A range of area under curve over a 24h interval (AUC(24h))/MIC ratios and selected E. coli strains were investigated using the dynamic models. Continuous incubation for three days in the presence of difloxacin or orbifloxacin resulted in losses in E. coli susceptibility. An AUC(24h)/MIC (AUC(24h)/MPC)-dependent fluoroquinolone activity and selection of E. coli mutants was confirmed. Maximum losses in susceptibility occurred at AUC(24h)/MIC ratios of 54 (orbifloxacin) and 57.3 (difloxacin). AUC(24h)/MIC ratios of 169.8 (orbifloxacin) and 199.5 (difloxacin) were estimated to be protective against the selection of E. coli mutants, and the corresponding ratios based on AUC(24h)/MPC predictions were 34 (orbifloxacin) and 36.3 (difloxacin). When integrating our in vitro data with pharmacokinetic data in dogs, the conventional clinical doses of both drugs were found to be inadequate to attain the above protective values for 90% of the mutant subpopulation (AUC(24h)/MPC(90)). Both target mutations, esp. at codon 83 (Ser to Leu) of gyrA, and overexpression of efflux pumps contributed to resistance development, with mutants also showing decreased susceptibility to enrofloxacin and marbofloxacin. Additional studies would determine the role of mutations found outside the QRDR, at codon 24 of gyrA, and at codon 116 of parC, and establish the significance of these observations in vivo. 相似文献
5.
6.
Awji EG Tassew DD Lee JS Lee SJ Choi MJ Reza MA Rhee MH Kim TH Park SC 《Veterinary dermatology》2012,23(4):376-80, e68-9
Background – The problem of antibacterial drug resistance is increasing worldwide, in part due to the therapeutic concentrations currently used based on the minimal inhibitory concentration (MIC) as a measure of potency are often the very concentrations required to selectively enrich the resistant mutant portion of the population. A mutant prevention concentration (MPC)‐based dosing strategy is suggested to improve the therapeutic outcome based on the MIC. Objective – Our aim was to investigate the MPC and mechanism of resistance to various fluoroquinolones using recent Staphylococcus pseudintermedius isolates from canine pyoderma. Methods – The broth microdilution method for MIC and a series of agar plates containing different concentrations of fluoroquinolones were inoculated with ～1010 colony‐forming units of the bacterial culture for MPC were used. PCR was used to identify mutation in the resistant isolates. Results – The rank order of potency based on MIC and MPC was ciprofloxacin = enrofloxacin ≥ marbofloxacin > difloxacin ≥ orbifloxacin. Integrating our data with reported pharmacokinetic data at the recommended dose ranges revealed that only high doses of ciprofloxacin, enrofloxacin and marbofloxacin could achieve a maximal plasma concentration (Cmax) greater than the MPC of 90% of isolates (Cmax/MPC90). The overall rank of potency against S. pseudintermedius, based on Cmax/MIC, Cmax/MPC, the area under concentration–time curve (AUC)/MIC and AUC/MPC values, was in decreasing order: enrofloxacin > ciprofloxacin ≥ marbofloxacin ≥ orbifloxacin = difloxacin. Sequencing of the quinolone resistant determining region of gyrA, gyrB, grlA and grlB of resistant strains showed a base‐pair substitution in both gyrA and gyrB that resulted in Ser‐84 to Leu and Ser‐80 to Arg amino acid changes, respectively. Conclusions and clinical importance – High doses of ciprofloxacin, enrofloxacin and marbofloxacin could minimize the selection of resistant mutants, whereas the possibility of selecting mutants with the conventional doses of difloxacin and orbifloxacin, and low clinical doses of all fluoroquinolones, seems high. 相似文献
7.
Awji EG Damte D Lee SJ Lee JS Kim YH Park SC 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(8):1091-1094
The in vitro activity of 15 antimicrobial agents against clinical isolates of Staphylococcus pseudintermedius, Staphylococcus aureus, Escherichia coli, Pasteurella spp. and Streptococcus canis from dogs was investigated. For Staphylococcus spp., the highest frequency of resistance was observed for penicillin, followed by ampicillin, tetracycline and chloramphenicol. The highest frequency of resistance in E. coli isolates was recorded for tetracycline and streptomycin. Pasteurella spp. and S. canis had the highest resistance rate for tetracycline and chloramphenicol. Most isolates showed full susceptibility to low-level resistance to colistin, florfenicol and fluoroquinolones. Further studies using larger number of isolates from both healthy and diseased dogs would provide a broader picture of antimicrobial resistance at a national level and promote prudent use of antimicrobial agents in companion animals. 相似文献
1