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171.
Cloacal swabs from 62 green iguanas (Iguana iguana), including 47 wild and 15 domestic ones from five parishes of Grenada, were sampled during a 4‐month period of January to April 2013 and examined by enrichment and selective culture for the presence of Salmonella spp. Fifty‐five per cent of the animals were positive, and eight serovars of Salmonella were isolated. The most common serovar was Rubislaw (58.8%), a serovar found recently in many cane toads in Grenada, followed by Oranienburg (14.7%), a serovar that has been causing serious human disease outbreaks in Japan. Serovar IV:48:g,z51:‐ (formerly, S. Marina) highly invasive and known for serious infections in children in the United States, constituted 11.8% of the isolates, all of them being from domestic green iguanas. Salmonella Newport, a serovar recently found in a blue land crab in Grenada, comprised 11.8% of the isolates from the green iguanas. The remaining four less frequent serovars included S. Javiana and S. Glostrup. Antimicrobial susceptibility tests conducted by a disc diffusion method against amoxicillin–clavulanic acid, ampicillin, cefotaxime, ceftazidime, ciprofloxacin, enrofloxacin, gentamicin, nalidixic acid, streptomycin, tetracycline and trimethoprim–sulfamethoxazole showed that drug resistance is minimal, with intermediate susceptibility, mainly to streptomycin, tetracycline and cefotaxime. This is the first report of isolation and antimicrobial susceptibilities of various Salmonella serovars from wild and domestic green iguanas in Grenada, West Indies.  相似文献   
172.
[目的]建立一种快速检测李氏杆菌病的方法。[方法]通过对实验室保存的5株李氏杆菌分离株进行药敏试验,用甲醛灭活苗免疫试验动物,制备特异性抗体,将特异性抗体与抗原进行平板凝集试验。[结果]分离菌株对氨苄西林、庆大霉素、链霉素高度敏感,对头孢唑啉、左氧氟沙星和多粘菌素中度敏感,对头孢他啶、头孢呋辛钠耐药性较强。通过用甲醛灭活苗免疫试验动物来制备特异性抗体,将特异性抗体与抗原做平板凝集试验,建立一种快速准确检测李氏杆菌病的方法。[结论]成功建立了一种快速检测李氏杆菌病的方法。  相似文献   
173.
华阴市小麦“3414”试验研究   总被引:1,自引:0,他引:1  
张海红 《安徽农业科学》2014,(33):11678-11679,11706
[目的]为了提出适宜华阴市小麦配方施肥方案.[方法]对小麦“3414”肥效试验结果进行分析,探索氮磷钾不同与小麦产量的关系.[结果]确定适宜华阴市小麦最高产量和最佳产量的施肥模式和目标产量,同时确定单因子肥效效应方程.[结论]该研究可以为华阴市小麦测土配方施肥提供依据.  相似文献   
174.
超声波在原木内部传播理论研究   总被引:1,自引:0,他引:1  
超声波技术在木材无损检测中已有广泛的应用,尤其是一些研究表明超声波在原木内部的传播规律对无损检测效果产生重要影响.根据弹性波在固体介质中的传播理论,通过对微小单元体的受力分析,得出弹性动力学运动微分方程,并在此基础上,根据正交各向异性介质的弹性常数,应力与应变之间的相互关系,几何方程(应变和位移的关系)以及超声波传播(无旋波)的方向向量,最终得出以位移表示的运动微分方程;然后利用分离变量法,建立超声波在原木内部传播过程中的位移方程和速度方程.  相似文献   
175.
为了拍摄烤烟烟叶反射和透射图像并实时显示物距大小,研发了烟叶图像拍摄与物距显示试验装置,该装置包括图像采集装置和物距测量显示装置。图像采集装置由支架、载物板、标准光源等组成,构成图像的采集平台,物距测量显示装置由容栅传感器(KX/MS-50)及数码显示系统构成,用于显示拍摄物距的大小。拍摄装置可以同时采集烟叶的反射和透射图像,反射图像和透射图像的物距大小通过测量系统显示。该文给出该装置的主要功能和设计方案,并对装置中的各子系统的设计方法和实现技术进行了介绍。  相似文献   
176.
177.
Sixteen countries, including Bangladesh, have reported the presence of tilapia lake virus (TiLV), an emerging tilapia pathogen. Fish polyculture is a common farming practice in Bangladesh. Some unusual mortalities reported in species co-cultivated with TiLV-infected tilapia led us to investigate whether any of the co-cultivated species would also test positive for TiLV and whether they were susceptible to TiLV infection under controlled laboratory experiments. Using 183 samples obtained from 15 farms in six districts across Bangladesh, we determined that 20% of the farms tested positive for TiLV in tilapia, while 15 co-cultivated fish species and seven other invertebrates (e.g. insects and crustaceans) considered potential carriers all tested negative. Of the six representative fish species experimentally infected with TiLV, only Nile tilapia showed the typical clinical signs of the disease, with 70% mortality within 12 days. By contrast, four carp species and one catfish species challenged with TiLV showed no signs of TiLV infection. Challenged tilapia were confirmed as TiLV-positive by RT-qPCR, while challenged carp and walking catfish all tested negative. Overall, our field and laboratory findings indicate that species used in polycultures are not susceptible to TiLV. Although current evidence suggests that TiLV is likely host-specific to tilapia, targeted surveillance for TiLV in other fish species in polyculture systems should continue, in order to prepare for a possible future scenario where TiLV mutates and/or adapts to new host(s).  相似文献   
178.
拖拉机驾驶员颈部疲劳的肌电评价   总被引:3,自引:2,他引:1  
为了了解拖拉机驾驶员颈部疲劳状况,该文在模拟拖拉机倒车作业的基础上,对驾驶员颈部胸锁乳突肌的表面肌电信号进行了测试,选取积分肌电值、平均功率频率、小波分解系数等特征量对肌电信号进行时域、频域以及时频域分析。结果表明:拖拉机驾驶员颈部疲劳后胸锁乳突肌的积分肌电值、平均功率频率、小波分解系数都降低,疲劳前后各特征量存在显著性差异(P<0.05),这些特征量都可以有效评价拖拉机驾驶员的颈部疲劳。  相似文献   
179.
ABSTRACT

1. The objective of this study was to develop a machine vision method for analysing exterior parameters of chicken eggs to automate the stage of primary sorting.

2. The developed algorithm based on predetermined thresholds calculated egg quality indicators, including geometric dimensions, shape index and the mottling grade. The algorithm was implemented with an experimental setup that combined the image-based and the candling methods. A total of 400 egg samples were analysed.

3. Comparison of results of the algorithm with those obtained using the traditional manual method showed that mean value of radii values difference was 0.095 ± 0.058 mm for the sharp and 0.080 ± 0.047 mm for the blunt end of the egg, with standard deviations of 0.58 mm and 0.49 mm, respectively.

4. The correlation coefficient between the shape index values determined by the two methods was 0.93; the standard deviation of absolute differences between corresponding values was 1.05%.

5. The results of mottling grade estimation were compared using F-measure and confusion matrix.

6. The results allow the possibility to perform the assessment of egg exterior quality factors in an automatic mode, independent of the expertise of a grader.  相似文献   
180.
AIM:To investigate the effect of LY980503(a benflumetol derivative)on multidrug resistance of tumor cell line using DNA microarray.METHODS:Total RNA was extracted from multidrug resistant MCF/DOX cell line. cDNA microarray containing 320 cDNAs was used to detect the gene expression profile.RESULTS:9 down-regulated genes and 1 up-regulated gene were identified after multidrug resistant MCF/DOX cells were treated with LY980503.CONCLUSION:LY980503 can effectively reverse the resistance of MCF/DOX to DOX in vitro by adjusting the expression of multi-genes.  相似文献   
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