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81.
This case study describes the first genetically confirmed and clinically manifested autochthonous Ehrlichia canis infection in a 9‐year‐old female mixed‐breed dog from Romania. Health screening of the dog included clinical examination, evaluation of stained peripheral blood smear and hematologic variables, as well as serologic testing and molecular analysis. Clinical signs included fever, apathy, dehydration, pale mucous membranes, and weakness. The microscopic examination of the blood smear and immunologic assays for Borrelia burgdorferi, Anaplasma phagocytophilum, and E canis antibodies, and for Dirofilaria immitis antigen yielded negative results. Hematologic abnormalities included moderate nonregenerative anemia, leucopenia with neutropenia, and moderate thrombocytopenia. The biochemical abnormalities identified were hypoalbuminemia, and mildly increased serum enzyme activities of AST and ALT. In addition, increased urea and creatinine levels associated with low urine specific gravity and proteinuria were also present. Nested PCR amplification of the partial E canis 16S rRNA gene demonstrated the presence of this rickettsial pathogen in the dog's blood, which subsequently was confirmed through sequencing based on the 100% homology with GenBank deposited E canis isolates. After specific treatment with doxycycline (10 mg/kg, orally, SID) for one month, the proteinuria, and hematologic and serum biochemical abnormalities with the exception of mild azotemia resolved. This report supports the geographical expansion of canine ehrlichiosis caused by E canis in nonendemic regions of Europe.  相似文献   
82.
钟召兵  王宁 《中国动物检疫》2014,31(11):101-105
为深入了解畜禽舍环境中气载细菌微生物的空气动力学粒径分布规律,并评估其潜在的健康危害风险,采用Andersen-6级微生物空气采样器以血-琼脂培养基、沙氏培养基和高氏合成1号培养基为采样介质,对鸡舍、猪舍、牛舍环境中空气样品进行系统定点取样、测定及分析。研究结果表明,鸡舍环境中气载需氧菌含量最高,猪舍次之,牛舍最低;空气细菌粒径分布均为第Ⅰ级最高,鸡舍空气粒径呈偏态分布,牛舍、猪舍分别在第Ⅲ级和第Ⅳ级出现第2个峰值。携带细菌可吸入微粒在猪舍环境中比例最大。空气真菌与放线菌均在第Ⅳ级最高,携带真菌和放线菌可吸入粒子的比例显著大于细菌(P<0.05)。鸡舍、猪舍、牛舍空气微生物粒径各级分布比例基本一致。在鸡舍、猪舍、牛舍每天约有6.1×105CFU、4.7×104CFU和3.6×104CFU气载细菌微生物可分别进入人和动物小支气管或直接进入肺泡,从而对人和动物健康构成潜在危害。  相似文献   
83.
天莹 《内蒙古草业》2001,13(4):27-32
目前,自然灾害已成为制约我区农牧业稳定持续发展的一大障碍。本文对其定义、类型及危害进行研究,然后总结多年来我区防灾抗灾的成就。在此基础上,提出今后防灾减灾的思路。  相似文献   
84.
宁夏野生甘草分布空间异质性及分布格局研究   总被引:4,自引:4,他引:4  
运用统计学中的半方差分析、分维分析和克里格插值方法对宁夏野生甘草Glycyrrhiza uralensis的分布格局及其过程进行了研究.结果表明,宁夏野生甘草不同尺度空间分布的异质性不十分强烈,在整个所有尺度上受简单过程控制.分布格局在较小尺度上受随机过程控制,而在较大尺度上受自相关关系影响较大.当甘草种群间的距离在0~58 m内,样点内甘草株数与距离有自相关关系,而当甘草种群间的距离大于58 m时,样点间甘草分布的变化失去了自相关关系.甘草的克隆繁殖方式和土壤质地的空间异质性及鼠兔危害是导致甘草分布空间异质性的重要原因.  相似文献   
85.
The article reviews the outbreaks and distribution of African swine fever (ASF) in South Africa since the first probable outbreak that occurred in the Koedoesrand Ward in 1926. Retrospective data on the ASF outbreaks in South Africa were obtained from the World Organisation for Animal Health (OIE) disease database and the South African veterinary services annual reports in addition to published articles and online sources. South Africa has experienced many outbreaks that can be divided into 2 time periods: the period before the development of the OIE diseases database (1993) and the period after. More than 141 outbreaks of ASF were reported during the first period. Since the development of OIE disease database, 72 outbreaks directly involving 2968 cases, 2187 dead and 2358 killed pigs mainly in smallholder pig farms were reported. The median number of cases for a given ASF outbreak is 17, but in 50% of outbreaks no pigs were killed for prevention. The most important ASF outbreak was reported in April 2014 in the Greater Zeerust district (North West province) involving 326 cases and 1462 killed pigs. However, the outbreak with highest mortality involving 250 pigs was reported in 2016 (Free State province). According to phylogenetic analysis, nine p72 genotypes (I, III, IV, VII, VIII, XIX, XX, XXI and XXII) have been identified in South Africa. Season-wise, more outbreaks were recorded during summer. It was also observed that the OIE disease database could contain errors that would have been introduced through compiled forms at country level. Spatiotemporal studies on ASF outbreaks in South Africa are therefore required in order to assess statistically and quantitatively the clustering of outbreaks over space and time.  相似文献   
86.
Visual estimation techniques were used between October 1976 and May 1977 on the fish fauna of an enclosed mid-intertidal pool in the eastern Cape, South Africa, to test the usefulness and accuracy of this non-consumptive census method. In January, 1977, two pools were censused for fish, then poisoned using the ichthyocide ‘pronoxfish’ and all fish collected. Forty species in 21 families were obtained from the two stations. The accuracy of visual estimates varied with the species of fish. Secretive and cryptically coloured types, as well as species which Inhabit crevices, were underestimated, between 0 and 86% being counted. Other fish with protective colours but that occur more openly and do not react adversely to divers, as well as schooling species, were also underestimated, but up to 100% of the total were observed. Those which occur singly or in small groups in the water column were counted more accurately, with 57 to 100% of the actual number being seen. Correction factors were calculated from these data and applied to a census taken of one pool in May. Comparisons of corrected and actual numbers Indicate that these factors were relatively accurate for non-secretive species. The factors will, however, vary for each species, from observer to observer, depending on their personal experience, and from area to area.  相似文献   
87.
利福平乙基纤维素微球在小鼠体内的组织分布   总被引:1,自引:0,他引:1  
以有机相分散、溶媒扩散二步法制备了利福平乙基纤维素微球,粒径范围2.5-12.5μm,其中粒径2.5-5.0μm的约占63%。采用微生物测定法研究了利福平乙基纤维素微球静脉给药后,利福平在小鼠体内的组织分布,且与游离利福平在小鼠体内组织分布进行了比较,小鼠单剂量静脉注射游离利福平或利福平乙基纤维素微球(相当于利福平原药)10mg/kg,测定0.5、1、3、7、12、24、48、72、120、168h共10个时间点各组织中的药物浓度。结果表明,游离利福平给药组和利福平乙基纤维素微球给药组在12h内均以肝脏中药物浓度为最高,为9.96-22.41μg/g,在3h内微球给药组高于游离药物给药组,7、12h微球给药组的药物浓度迅速下降,低于游离药物给药组;肾脏的药物浓度在12h内微球给药组明显低于游离药物给药组,24-168h微球给药组的药物浓度下降迟缓,显著高于游离药物给药组直到168药物浓度始终是微球给药组高于游离药物给药组,12h游离药物给药组已不能检出药物含量,而微球给药组直到168h仍维持在5.44μg/g,接近游离药物给药组的最高峰值;血清中利福平浓度在48h已不能检出,而微球给药组在168h为1.33mg/L;心脏、用脏微球给药组和游离药物给药组的药物浓度变化无统计学意义,与游离药物相比,利福平微球明显提高了肺脏中的药物分布,降低了利福平对肝脏、肾脏的毒性,并显著延缓了药物代谢,说明利福平微球具有长效、靶向作用。  相似文献   
88.
雪凝灾后厩肥和尿素对新植鸭茅鲜草产量的影响   总被引:3,自引:0,他引:3  
2007-2008年进行了厩肥和尿素配合施用对新植鸭茅Dactylis glomerata栽培草地鲜草产量的影响研究,结果表明,在经历了2008年年初持续20多天雪凝灾害之后,6个厩肥和尿素处理组合的鲜草产量差异显著,施厩肥30 000 kg/hm2与施尿素75、175、275 kg/hm2的处理组合的鲜草产量均极显著高于对照,厩肥施用量30 000 kg/hm2的处理组合鲜草产量较高,其中,鲜草产量最高的施肥组合为厩肥30 000 kg+尿素175 kg/hm2,而最经济的施肥组合应该是厩肥30 000+尿素75 kg/hm2。  相似文献   
89.
对湘中紫色页岩区芦竹的生物量和养分分布进行初步研究.结果表明:当年生芦竹杆(含叶)养分含量高于多年生,因此不宜砍伐利用当年生芦竹杆;根茎养分含量较高,是系统中良好的养分贮存库.一年生、二年生、五年生、八年生芦竹的生物量分别为293.00、5258.29、6746.87和480.86 kg.hm-2.  相似文献   
90.
匀加速直线运动中柔索的张力分布及其稳定形状   总被引:2,自引:0,他引:2  
吴舒辞 《森林工程》2002,18(6):34-35
本文以一段考虑自重的柔索牵引一质点作匀加速直线运动为模型,采用拖力端柔索为水平的边界条件近似,求得了柔索中张力沿弧长的分布函数,以及柔索稳定形状的参量表达式,并将所有结果与悬链线进行了有意义的比较。  相似文献   
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