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排序方式: 共有645条查询结果,搜索用时 15 毫秒
31.
新疆不同地区牛源大肠杆菌耐药性分析 总被引:1,自引:0,他引:1
This study was aimed to investigate the resistance of Escherichia coli isolates from cattle farms in Xinjiang to antibiotics. The resistances of Escherichia coli isolates from cattle farms in five regions to commonly used antibiotic were determined using microdilution broth assay. Escherichia coli isolates were highly resistant to ampicillin (up to 39.3%) in all regions, and existed multidrug-resistant, but zero resistance was the dominant. Escherichia coli isolates from E cattle farm in Cherqi town, Baicheng county, exhibited resistant to three kinds of quinolones (6.7%). The results suggested that the resistances of Escherichia coli isolates to commonly used antibiotics were not serious in Xinjiang. 相似文献
32.
建立兽用抗生素注射液与可溶性粉剂中非法添加对乙酰氨基酚、安乃近、安替比林、萘普生、氨基比林5种药物的高效液相色谱—二极管阵列检测分析方法。样品经甲醇超声提取后进行液相色谱分析,采用CAPCELL PAK MG C18(4.6 mm×250 mm,5μm)色谱柱,柱温30℃,流动相为乙腈和磷酸盐缓冲液,梯度洗脱,检测波长229 nm,流速1.0 m L/min。对乙酰氨基酚、安乃近、安替比林、萘普生、氨基比林进样量分别在5.04~100.88、12.04~240.72、5.04~100.72、2.02~40.40、5.02~100.32μg/m L范围内呈良好的线性关系;平均加样回收率(n=5)分别为97.9%~102.8%、91.9%~98.8%、96.2%~101.1%、94.1%~102.3%、96.0%~102.8%,RSD分别为1.0%~3.1%、0.9%~6.4%、1.7%~4.2%、1.4%~3.9%、0.9%~4.8%。该方法快捷、简便,其准确性和灵敏度经方法学验证能很好地满足检测多种抗生素中非法添加解热镇痛类药物的筛查要求。 相似文献
33.
Two agricultural soils were collected from Dahu and Pinchen counties and swine manure compost (SMC) from Pingtung County in Taiwan, China to investigate the sorption and dissipation of three tetracyclines (TCs), i.e., oxytetracycline (OTC), tetracycline (TC) and chlortetracycline (CTC), in compost, soils and soil/compost mixtures with different organic carbon (OC) contents. There were seven treatments in total. TCs were most strongly adsorbed to SMC in all treatments due to the high OC content. When SMC was present in the soils, the sorption of TCs was significantly enhanced, which might be attributed to the increased OC content and CEC. The adsorption of TCs showed non-linear adsorption isotherms and fitted well to the Freundlich model. After 49 d of incubation at 25 oC in soils and soil/compost mixtures in the dark, TCs elapsed in all substrates, with the time required for 50% degradation (DT50) between 20 and 41 d, and the time for 90% degradation (DT90) between 68 and 137 d. Soil amended with compost enhanced the stability of TCs and reduced their mobility. The dissipation of TCs in a soil environment was slow, indicating that these compounds might be persistent in soil. 相似文献
34.
35.
Fouzia Rhazi Filali Abdelhamid Zaid Zoubir Zekhnini Jean-Marie Frere 《Comparative immunology, microbiology and infectious diseases》1997,20(4):335-344
Three thermophilic bacteria strains, designated strain BS1, BS2 and BS3, resistant to β-lactam antibiotics, and leaving at an optimal temperature for growth of about 50°C, were isolated from traditional baths in Meknes-city in Morocco. Physiological and biochemical studies showed that these organisms belong to Gram positive Bacilli. They could not be identified with the Bergey's Manuel of Systematic Bacteriology (1986). The dosage of β-lactamase during the exponential growth phase has revealed that the strain BS3 produces a maximal amount of this enzyme. Studies aimed at determining the optimal conditions for incubation and growth have been performed in order to optimize the excretion of β-lactamase by BS3 cells and thus facilitate the purification and and characterization of this enzyme. 相似文献
36.
兽药磺胺二甲嘧啶在土壤中的生态行为 总被引:10,自引:0,他引:10
通过室内培养和土壤薄层层析等实验方法,研究了磺胺二甲嘧啶对土壤微生物的毒性及其在土壤中的降解、迁移特性。结果显示:在土壤磺胺二甲嘧啶浓度为1mg kg^-1时,土壤中细菌和真菌数量明显减少(p〈0.05),但随时间延长,该抑制作用变缓;磺胺二甲嘧啶在土壤中降解缓慢,持留时间久,在灭菌土和未灭菌土中的半衰期分别为223.9d和102.4d,并容易在土壤中迁移和渗漏,迁移系数R大于0.7,迁移和渗漏速度受介质pH的影响,在非中性环境下,移动和渗漏能力增强。表明磺胺二甲嘧啶是一种在土壤中不易被降解、容易迁移和渗漏到水体、对土壤微生物和水体产生危害的新型污染源。 相似文献
37.
规模化养殖畜禽粪主要有害成分测定分析研究 总被引:148,自引:3,他引:148
随着我国规模化养殖业的快速发展,畜禽粪中重金属、兽药残留、盐分及有害菌等有害污染物的增加,构成影响农田土壤健康功能的限制因素,甚至带来生态环境风险。对我国7个省、市、自治区的典型规模化养殖畜禽粪的主要化学组成进行了测定。结果表明,规模化养殖畜禽粪中富含有机质、氮、磷、钾及钙、镁、铁、钠、锰、钴等矿质元素;砷、铜、锌、铬等重金属及盐分含量较高,55个猪粪、鸡粪样中,Cu、Zn、Cr、As含量变幅分别为10.7~1591mg/kg、71.3~8710.mg/kg、0~688.mg/kg、0.01~65.4.mg/kg。同时多有四环素类抗生素残留,32个猪粪样中,土霉素、四环素、金霉素平均含量分别为9.09.mg/kg、5.22.mg/kg、3.57.mg/kg;23个鸡粪样中,土霉素、四环素、金霉素平均含量分别为5.97.mg/kg2、.63.mg/kg1、.39.mg/kg。因此,规模化养殖畜禽粪对农田施用后存在潜在危害性,规模化养殖畜禽粪必须进行无害化处理,才能资源化利用。 相似文献
38.
Novel antibiotics as inhibitors for the selective respiratory inhibition method of measuring fungal:bacterial ratios in soil 总被引:7,自引:0,他引:7
The use of the selective inhibition (SI) method for measuring fungal:bacterial ratios may be limited due to biocide selectivity and the overlap of antibiotic activity. This study evaluated novel pairs of antibiotics for their specificity in soils of different origins and their potential reduction in inhibition of non-target organisms. Four soils selected for this study were from a semi-arid shrub-steppe, a loblolly pine forest and two grassland sites (restored and farmed prairie plots). Three bactericides were tested: oxytetracycline hydrochloride, streptomycin sulphate, and bronopol. Three fungicides were tested: captan, ketoconazole, and nystatin. The inhibitor additivity ratio and fungal:bacterial ratios were calculated from control and treated soils where inhibition was measured as CO2 respiration reduction with biocides. We were able to minimize non-target inhibition by the antibiotics to <5% and thus calculate reliable fungal:bacterial ratios using captan to inhibit fungi in all four soils, and bronopol to inhibit bacteria in three of the four soils. The most successful bactericide in the restored prairie was oxytetracycline-HCl. Our results demonstrate that application of novel antibiotics is not uniformly successful in soils of different origin and that the SI technique requires more than just optimization of antibiotic concentration; it also requires optimization of antibiotic selection. 相似文献
39.
鸭大肠杆菌超广谱β-内酰胺酶检测(ESBLs)及药物敏感性测定 总被引:2,自引:0,他引:2
对国内7个省份临床分离的32株鸭大肠杆菌进行超广谱β-内酰胺酶(ESBLs)检测及药物敏感性研究。结果表明,32株分离的鸭大肠杆菌中产ESBLs菌株7株,阳性检出率为21.87%;产ESBLs菌株对常用头孢三代及半合成青霉素类药物的敏感率低于42.9%,耐药率则高于28.6%,对阿莫西林、氨苄西林、头孢噻呋的耐药率高达100%。产酶菌株和非产酶菌株对新型头孢四代产品头孢吡肟及碳青霉烯类药物亚胺培南、美罗培南的敏感率高于96%。加酶抑制剂的β-内酰胺类抗生素如阿莫西林/棒酸、氨苄西林/舒巴坦、头孢哌酮/舒巴坦等对产酶菌株和非产酶菌株的敏感率全部高于未加酶抑制剂的单方药物。产ESBLs菌株存在多重耐药现象,酶抑制剂能够部分解决此类耐药性问题。 相似文献
40.
饲用益生素与抗生素的比较研究 总被引:10,自引:0,他引:10
肖振铎 《吉林农业大学学报》2002,24(3):1-6
对饲用益生素与抗生素的研究进行了比较分析,主要对其研究的历史和现况,作用机理,合理使用的条件与可行性进行了综述。 相似文献