不同物流条件对荔枝采后贮藏 期间果实品质的影响

荔枝果实采后常温条件下贮藏极易褐变、腐烂,低温可以延长果实的贮藏期.以妃子笑荔枝果实为试验材料,通过测定果实不同生理指标,研究预冷和物流方式(低温运输和常温运输)对荔枝采后贮藏期间果实品质的影响.研究结果表明,荔枝采后预冷且低温条件下运输能够较好地维持妃子笑荔枝贮藏期间的果实品质,该方法明显降低了荔枝果实的褐变指数、腐烂率和相对电导率,较好地维持了果实中的可溶性固形物(TSS)、可滴定酸(TA)和VC的含量.研究结果为将来荔枝冷链物流技术的应用和改进提供数据支撑和理论依据.     

Retrospective Review of Carriage Horse and Mule Welfare in Charleston,South Carolina (2009–2012)

Equine Welfare and Carriage Horse Companies have been recently highlighted as matters of public concern, although little data exists to describe working conditions, municipal regulations, and veterinary attention. In light of the current pandemic of unwanted horses in this country, it is prudent for the veterinary community to identify objective measurements of satisfactory equine welfare in the carriage horse industry to regulate and maintain working horses in sound conditions. Retrospective data from a carriage company in South Carolina was collected from 2009 to 2012. Variables included days in work, hours and/or tours worked, veterinary charges, management practices, and environmental conditions. City veterinary reports were also reviewed for all five local carriage companies. The average number of days in work per animal ranged from 163 to 188 per year. On average, each animal performed 4.6 hour long tours per working day, resulting in an average 865 tours per year. Each animal cost on average $2.00 per day in veterinary costs, and $0.84 of each animal's tour went toward veterinary bills. Welfare among carriage horses is a subject on which equine veterinarians should be well versed; not only to answer questions from clientele but also to promote good working and living conditions for these animals in an effort to stem the number of unwanted horses in America. The carriage company reported in detail here provides acceptable welfare for their animals. Prospective studies are needed to collect objective, evidence-based data regarding stress levels in the animals.     

DIFFUSION‐WEIGHTED MAGNETIC RESONANCE IMAGING OF THE NORMAL CANINE BRAIN

Diffusion‐weighted imaging (DWI) MRI has been primarily reported as a method for diagnosing cerebrovascular disease in veterinary patients. In humans, clinical applications for diffusion‐weighted MRI have also included epilepsy, Alzheimer's, and Creutzfeld–Jakob disease. Before these applications can be developed in veterinary patients, more data on brain diffusion characteristics are needed. Therefore, the aim of this study was to evaluate the distribution of diffusion in the normal canine brain. Magnetic resonance imaging of the brain was performed in ten, clinically normal, purpose‐bred beagle dogs. On apparent diffusion coefficient maps, regions of interest were drawn around the caudate nucleus, thalamus, piriform lobe, hippocampus, semioval center, and cerebral cortex. Statistically significant differences in mean apparent diffusion coefficient were found for the internal capsule, hippocampus, and thalamus. The highest apparent diffusion coefficient (1044.29 ± 165.21 μm²/s (mean ± SD (standard deviation)) was detected in the hippocampus. The lowest apparent diffusion coefficient was measured in the semioval center (721.39 ± 126.28 μm²/s (mean ± SD)). Significant differences in mean apparent diffusion coefficients of the caudate nucleus, thalamus, and piriform lobe were found by comparing right and left sides. Differences between brain regions may occur due to differences in myelination, neural density, or fiber orientation. The reason for the differences between right and left sides remains unclear. Data from the current study provide background for further studies of diffusion changes in dogs with brain disease.     

Human dendritic cells transfected with MUC1 mRNA induce lethal effect of cytotoxic T-lymphocytes on non-small cell lung cancer in vitro

AIM：To investigate the specific anti-tumor effects of mature dendritic cells (DCs) transfected with amplified mucin 1 (MUC1) mRNA in vitro. METHODS：DCs separated and purified from the peripheral blood mononuclear cells were induced in vitro and then identified by flow cytometry. pcDNA3.1（+）-MUC1 plasmid was constructed and was able to transcribe MUC1 mRNA in vitro. The MUC1 mRNA was transfected into DCs by electroporation. MUC1-transfected DCs were used to induce T cells to be cytotoxic T-lymphocytes. Quantitative real-time PCR was performed to assess MUC1 mRNA expression in transfected DCs. The proliferation of T cells was examined by MTT assay. The proportion of CD8+ cells in the T cells was determined by flow cytometry and the specific cytotoxicity was measured by LDH assay. The secretion of IFN-γ was detected by ELISA. RESULTS：The marker gene expression in the DCs transfected with MUC1 mRNA was significantly increased compared with control group, peaking at 24 h. The transfection group showed the higher capacity to stimulate the proliferation of T cells compared with control group when the ratio of DCs to T cells was 1∶10. The proportion of CD8+ cells in transfection group was higher than that in control group. The lethal effect of special cytotoxic T-lymphocytes on target cells in transfection group was stronger than that in control group. The level of IFN-γ in the cell supernatant of transfection group was higher than that in control group. CONCLUSION：DCs plus MUC1 mRNA by electrical transfection induces specific anti-tumor effects, which provides an experiment evidence of using MUC1 as a target for immunotherapeutic strategy against non-small cell lung cancer.     

免疫压力下猪繁殖与呼吸综合征病毒的变异

为了解连续免疫压力下猪繁殖与呼吸综合征病毒（PRRSV）的变异规律,以及为猪繁殖与呼吸综合征病的防控提供科学依据,以贵州分离株 PRRSV AS 为研究对象,监测分析了 PRRSV 接种免疫猪群后其主要基因变异情况。结果表明：1）接种 PRRSV 后,免疫猪只未发生死亡现象,但出现轻微的临床表现和病理变化,且能在病变组织中分离到 PRRSV,并扩增出与预期大小相一致的 Nsp2和 GP5基因条带;2）对Nsp2基因,两次分离物 PRRSV AS-a、PRRSV AS-b 与原始病毒 PRRSV AS 的遗传距离相应为0．018和0．064,呈加速渐远趋势;PRRSV AS-a 发生16处点突变,其中9处为非同义突变,7处为同义突变;PRRSV AS-b 发生25处点突变,其中非同义突变12处,同义突变13处;从 PRRSV AS 向 PRRSV AS-a 到PRRSV AS-b 演变过程中,Nsp2基因编码蛋白第285～293位抗原指数发生不同程度改变,且演变趋势呈正向选择作用;3）对 GP5基因,两次分离物 PRRSV AS-a、PRRSV AS-b 与原始病毒 PRRSV AS 的遗传距离相应为0．004和0．015,变异趋势不明显;PRRSV AS-a 发生2处点突变,非同义突变和同义突变各1处;PRRSV AS-b 发生3处点突变,其中非同义突变2处,同义突变1处;从 PRRSV AS 向 PRRSV AS-a 到PRRSV AS-b 演变过程中,GP5基因编码蛋白重要抗原表位未发生改变,但其演变呈正向选择作用。说明,在连续免疫压力下 PRRSV 容易发生变异。     

宁夏农产品出口安全问题探讨

宁夏天赋优势、地载特色、人为骄绩,是全国唯一的回族自治区,是生产安全农产品的最佳地域之一。农产品出口是拉动宁夏经济发展的＂三辆马车＂之一,其质量安全与出口效益息息相关。笔者分析了宁夏农业和农产品质量安全的特点,从生产和监管2个方面10个单项剖析宁夏农产品的质量安全存在的问题及对出口贸易的影响,并提出了对策建议。对于认识宁夏农产品新优势和硬＂瓶颈＂,把握国际农产品质量安全新常态,推进政府决策和部门履职及提升宁夏农产品出口竞争力具有重要意义。     

鸡毒支原体病的防治

阐述了鸡毒支原体病的病原及流行特点、临床症状与病理变化,并介绍了该病的诊断方法与防治措施,以期为鸡场鸡毒支原体病的防治提供参考。     

西藏色林错-普若岗日国家公园潜在建设区夏季浮游植物群落生态特征

为了探究色林错-普若岗日国家公园潜在建设区夏季浮游植物群落及优势种生态特征,于2015年和2016年8月对浮游植物群落进行了调查分析,并运用生态位宽度、生态位重叠及生态响应速率等方法测定优势种的生态位量度。结果表明：（1）色林错-普若岗日国家公园潜在建设区共鉴定出浮游植物127种,隶属于3门5纲11目18科35属,其中优势种5种,隶属2门5属,优势种丰度和优势度在不同区域均有差异;（2）泉生菱形藻（Nitzschia fonticola）生态位宽度最大,嗜盐舟形藻（Navicula halophila）生态位宽度最小;（3）浮游植物优势种生态位重叠程度不高,种间竞争弱,群落结构较为稳定;（4）浮游植物优势种呈发展或衰退趋势是不同浮游植物优势种间竞争的必然结果。本研究结果为色-普国家公园潜在建设区浮游植物多样性积累基础数据,为探讨生态位分化理论下的种间关系、资源利用及生态适应机制提供参考。