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71.
To investigate the situations of predominant strain and antibiotic resistance of pathogenic Salmonella from chickens in Guangxi Zhuang Autonomous region, Salmonella was pre-enriched and isolated from tissues of clinical suspected chickens, and the Salmonella isolates were identified by biochemical test using ID 32E System for the identification of Enterobacteriaceae of VITEK System ATB Expression, serotypes were determined by slid agglutination test, antibiotic susceptibility was analyzed by ATB VET Susceptibility Test Strip of Enterobacteriaceae antibiotics.The results showed that 34 Salmonella strains were obtained from 310 clinical samples, of which 1 strain belonged to A serogroup, 1 to C2 serogroup, 15 to B serogroup, 14 to D serogroup and 3 to untyped serogroup, and S.typhimurium of B serogroup and S.pullorum of D serogroup were the predominant serotypes.All Salmonella isolates were sensitive to meropenem, imipenem, spectinomycine and apramycine, and the resistance rates to chloramphenicol, kanamycine and gentamicine were less than 10%, and the resistance rates to amoxicillin, streptomycine, flumequine, oxolinique, sulfamethizol, tetracycline and nitrofurantoine ranged between 50% and 90%, while the resistance rates to penicilline, oxacilline, fusidique, rifampicine and metronidazole reached to 100%.The results indicated that the serotype distribution of pathogenic Salmonella from chickens exhibited regional characteristics, and S.typhimurium and S.pullorum were the predominant serotypes in Guangxi Zhuang Autonomous region, and antibiotic resistance of Salmonella isolates was very serious which should be highly concerned.  相似文献   
72.
犬附红细胞体病的诊治体会   总被引:1,自引:0,他引:1  
犬附红细胞体病是由附红细胞体寄生于犬的血液、游离在血浆中或附着在红细胞表面所引起的一种血液寄生虫病。临床上以发热、贫血、黄疸等为主要特征。2004年以来,笔者诊治了8例病犬出现持续高热为主要特征的疾病,经临床与实验室诊断,确诊为犬附红细胞体病,经治疗5天后恢复正常。现举1例报道如下:  相似文献   
73.
东祁连山高寒草甸灌木和牧草营养成分含量季节变化动态   总被引:4,自引:4,他引:4  
比较分析了高寒草甸和灌丛草甸中分布的几种优势牧草和灌木的营养成分,发现灌木蛋白质含量高,利用价值大,是一种重要的蛋白质饲草资源。  相似文献   
74.
Two experiments were conducted to evaluate the effects of protein and lipid sources on cholesterol, AA, and fatty acid content, and on biological performance of juvenile Pacific white shrimp, Litopenaeus vannamei (Boone). In Exp. 1, seven isonitrogenous and isocaloric diets were prepared using fish meal; soybean meal; casein; fish meal + soybean meal; fish meal + casein; soybean meal + casein; and fish meal + soybean meal + casein. In Exp. 2, seven isonitrogenous and isocaloric diets were prepared using fish oil; soy oil; poultry fat; fish oil + soy oil; fish oil + poultry fat; soy oil + poultry fat; and fish oil + soy oil + poultry fat. Nine shrimp (average BW 570 mg) were stocked per 60-L tank, with three tanks per diet in each experiment. Shrimp were fed to apparent satiation twice daily for 28 d. Protein sources affected shrimp cholesterol, feed consumption, feed efficiency, protein consumption, protein efficiency ratio, and crude body fat (P < or = 0.05), but not weight gain, survival, hepatosomatic index, body protein, ash, and AA composition. Body (without hepatopancreas) cholesterol concentrations were the highest in shrimp fed the diet containing fish meal (0.81%), lowest for those fed the casein diet (0.64%), and intermediate in the other dietary treatment groups (range 0.71 to 0.74%). Lipid source also affected shrimp body cholesterol, body fatty acid profiles, and fatty acid profiles in the hepatopancreas (P < or = 0.05), but not growth performance, body protein, fat, ash, and cholesterol concentrations in the hepatopancreas. Shrimp fed the fish oil diet had the highest body cholesterol (0.75%), whereas those fed the soy oil or poultry fat diets were lowest (0.66 and 0.65%, respectively). Results indicate that by replacing fish meal and fish oil with soybean meal and soy oil, shrimp growth performance is not affected, but body cholesterol concentration is reduced.  相似文献   
75.
OBJECTIVE: To investigate the effects of acupuncture on neural activity detected by use of manganese-enhanced functional magnetic resonance imaging (fMRI) and elucidate the relationship between somatic acupoint stimulation and brain activation. ANIMALS: 40 New Zealand White rabbits. PROCEDURE: Manganese-enhanced fMRI was performed in anesthetized rabbits manipulated with electroacupuncture (EA) on Zusanli (ST-36) and Yanglingquan (GB-34) acupoints. Image acquisition was performed on a 1.5T superconductive clinical scanner with a circular polarized extremity coil. T1-weighted images were acquired sequentially as follows: baseline, after mannitol injection, after manganese infusion, and 5 and 20 minutes after initiation of EA. RESULTS: Changes in focal neural activity were detected by use of manganese-enhanced fMRI. Stimulation on Zusanli (ST-36) for 5 minutes resulted in activation of the hippocampus, whereas stimulation on Yanglingquan (GB-34) resulted in activation of the hypothalamus, insula, and motor cortex. Activation became less specific after 20 minutes of EA. Furthermore, stimulation on ipsilateral acupoints led to bilateral brain activation. CONCLUSIONS AND CLINICAL RELEVANCE: Each acupoint has a corresponding cerebral linkage, and stimulation on these points resulted in time-dependent neural activation. Understanding the linkage between peripheral acupoint stimulation and central neural pathways may provide a useful guide for clinical applications of acupuncture.  相似文献   
76.

Purpose  

Gardening (especially food growing) in urban areas is becoming popular, but urban soils are often very contaminated for historical reasons. There is lack of sufficient information as to the bioavailability of soil heavy metals to plants and human in urban environments. This study examines the relative leachability of Cr, Ni, As, Cd, Zn, and Pb for soils with varying characteristics. The speciation and mobility of these metals can be qualitatively inferred from the leaching experiments. The goal is to use the data to shed some light on their bioavailability to plant and human, as well as the basis for soil remediation.  相似文献   
77.
以QuEChERS作为样品前处理手段,建立测定水产品中扑草净残留的气相色谱-质谱法 (GC-MS)。样品以乙腈-二氯甲烷 (VV=8∶2) 混合溶液提取,提取液经吸附剂中性氧化铝、N-丙基乙二胺 (PSA)、纳米二氧化锆结合石墨化炭黑 (GCB) 净化后上机检测,内标法定量。结果显示,扑草净质量浓度介于5~200 μg·L−1线性关系良好,相关系数 (R2) 为0.9999。对草鱼 (Ctenopharyngodon idellus)、鳜 (Siniperca chuatsi)、中国对虾 (Penaeus chinensis)、海参 (Holothuria sp.) 和文蛤 (Meretrix meretrix) 进行4个水平的加标回收实验 (10、20、40和200 µg·kg−1),方法的加标回收率为85.8%~111.8%,相对标准偏差为1.2%~8.8%,满足GB/T 27404—2008《实验室质量控制规范 食品理化检测》中实验室质量控制规范。扑草净的检出限 (LOD, S/N≥3) 和定量限 (LOQ, S/N≥10) 分别为5和10 µg·kg−1。该方法简单、快速、灵敏、净化效果好,能满足水产品中扑草净残留的检测需求。  相似文献   
78.
水分胁迫对爱宕梨渗透调节的影响   总被引:5,自引:0,他引:5  
以二年生爱宕梨盆栽幼树为试材 ,研究水分胁迫对爱宕梨渗透调节的影响。结果表明 ,在水分胁迫下 ,随着土壤含水量的降低 ,梨树叶片组织相对含水量下降 ,叶水势增加。梨树在水分胁迫下具有一定的渗透调节能力 ,随着胁迫程度的增加 ,渗透调节物质K+ 含量和可溶性糖含量上升 ,当达到一定浓度后 ,诱发脯氨酸和游离氨基酸的大量生成。但水分胁迫超过一定程度后 ,细胞膜透性增加 ,原生质遭受破坏 ,植株枯死。  相似文献   
79.
为明确马铃薯甲虫自然种群的抗寒性,利用热敏电阻测定仪对马铃薯甲虫不同虫态过冷却点和冰点进行了测定。结果表明:不同虫态过冷却点和冰点之间存在显著性差异,其中以卵和成虫的过冷却点最低,分别为:(-13.73±0.93)℃和(-7.89±0.07)℃,显著低于其他虫态。3龄幼虫的过冷却点和冰点最高,分别为:(-6.21±0.08)℃和(-2.80±0.08)℃;过冷却点由低到高顺序为:卵<成虫<1龄幼虫<蛹<4龄幼虫<2龄幼虫<3龄幼虫;冰点由低到高的顺序为:卵<1龄幼虫<成虫<2龄幼虫<蛹<4龄幼虫<3龄幼虫;同一虫态个体间的过冷却点频次分布出现不同程度的变异,但均服从正态分布。研究结果为制定马铃薯甲虫在我国潜在分布和风险分析提供了科学依据。  相似文献   
80.
本研究在一膜一管四行大豆膜下滴灌的栽培模式下采用小管径小流量φ12-1.6L/h滴灌带与常规大管径大流量φ16-2.8L/h滴灌带对膜下滴灌大豆进行了4个主要性状指标的综合分析和评价。结果表明,φ16-2.8L/h滴灌带在干物质积累、叶面积指数、群体光合势、产量等方面均高于φ12-1.6L/h滴灌带。  相似文献   
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