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101.
去势术对雄性中华田园犬脂代谢的影响 《畜牧与饲料科学》2021,42(6):112-114
[目的] 研究去势术对雄性中华田园犬脂代谢的影响。[方法] 将12只年龄、体重相近的中华田园犬分为非手术组和去势组,对去势组中华田园犬进行去势手术,观察并测定术前第1天、术后第14天、术后第21天血清中甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白(LDL)、高密度脂蛋白(HDL)含量,以非手术组作为对照,分析去势术对雄性犬脂代谢的影响。[结果] 去势组与非手术组相比,血清中TG含量在第14天到第21天显著上升;血清中TC含量相比非手术组呈下降趋势;HDL第14天和第21天都低于非手术组;LDL都高于非手术组,整体呈上升趋势。[结论] 去势手术会影响雄性中华田园犬机体脂类代谢,会导致去势犬甘油三酯升高,总胆固醇和高密度脂蛋白下降,低密度脂蛋白上升。 相似文献
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Shunhua Yang Shangkao Deng Haiou Kuang Danyin Zhou Xueyang Gong Kun Dong 《Journal of insect science (Online)》2021,21(4)
The hexagonal structure of the honey bee comb cell has been the source of many studies attempting to understand its structure and function. In the storage area of the comb, only honey is stored and no brood is reared. We predicted that honey bees may construct different hexagonal cells for brood rearing and honey storage. We used quantitative analyses to evaluate the structure and function of the natural comb cell in the Chinese bee, Apis cerana cerana and the Italian bee, A. mellifera ligustica. We made cell molds using a crystal glue solution and measured the structure and inclination of cells. We found that the comb cells of A. c. cerana had both upward-sloping and downward-sloping cells; while the A. m. ligustica cells all tilted upwards. Interestingly, the cells did not conform to the regular hexagonal prism structure and showed irregular diameter sizes. In both species, comb cells also were differentiated into worker, drone and honey cells, differing in their diameter and depth. This study revealed unique differences in the structure and function of comb cells and showed that honey bees design their cells with precise engineering to increase storage capacity, and to create adequate growing room for their brood. 相似文献
105.
INVITED REVIEW—IMAGE REGISTRATION IN VETERINARY RADIATION ONCOLOGY: INDICATIONS,IMPLICATIONS, AND FUTURE ADVANCES 下载免费PDF全文
Yang Feng Jessica Lawrence Kun Cheng Dean Montgomery Lisa Forrest Duncan B. Mclaren Stephen McLaughlin David J. Argyle William H. Nailon 《Veterinary radiology & ultrasound》2016,57(2):113-123
The field of veterinary radiation therapy (RT) has gained substantial momentum in recent decades with significant advances in conformal treatment planning, image‐guided radiation therapy (IGRT), and intensity‐modulated (IMRT) techniques. At the root of these advancements lie improvements in tumor imaging, image alignment (registration), target volume delineation, and identification of critical structures. Image registration has been widely used to combine information from multimodality images such as computerized tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) to improve the accuracy of radiation delivery and reliably identify tumor‐bearing areas. Many different techniques have been applied in image registration. This review provides an overview of medical image registration in RT and its applications in veterinary oncology. A summary of the most commonly used approaches in human and veterinary medicine is presented along with their current use in IGRT and adaptive radiation therapy (ART). It is important to realize that registration does not guarantee that target volumes, such as the gross tumor volume (GTV), are correctly identified on the image being registered, as limitations unique to registration algorithms exist. Research involving novel registration frameworks for automatic segmentation of tumor volumes is ongoing and comparative oncology programs offer a unique opportunity to test the efficacy of proposed algorithms. 相似文献
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Yeon Soo Chung Jae Won Song Dae Ho Kim Sook Shin Young Kyung Park Soo Jin Yang Suk Kyung Lim Kun Taek Park Yong Ho Park 《Journal of veterinary science (Suw?n-si, Korea)》2016,17(2):199-206
Limited information is available regarding horse-associated antimicrobial resistant (AR) Escherichia (E.) coli. This study was designed to evaluate the frequency and characterize the pattern of AR E. coli from healthy horse-associated samples. A total of 143 E. coli (4.6%) were isolated from 3,078 samples collected from three national racetracks and 14 private horse-riding courses in Korea. Thirty of the E. coli isolates (21%) showed antimicrobial resistance to at least one antimicrobial agent, and four of the AR E. coli (13.3%) were defined as multi-drug resistance. Most of the AR E. coli harbored AR genes corresponding to their antimicrobial resistance phenotypes. Four of the AR E. coli carried class 1 integrase gene (intI1), a gene associated with multi-drug resistance. Pulsed-field gel electrophoretic analysis showed no genetic relatedness among AR E. coli isolated from different facilities; however, cross-transmissions between horses or horses and environments were detected in two facilities. Although cross-transmission of AR E. coli in horses and their environments was generally low, our study suggests a risk of transmission of AR bacteria between horses and humans. Further studies are needed to evaluate the risk of possible transmission of horse-associated AR bacteria to human communities through horse riders and horse-care workers. 相似文献
107.
采用牛提纯结核菌素皮内变态反应结合γ-干扰素试验、虎红平板凝集试验、试管凝结试验及ELISA法分别对重庆三峡库区肉牛结核病、布鲁菌病进行了抽样检测。结果显示,该区域肉牛结核病阳性检出率为1.2%,布鲁菌病阳性检出率为1.04%。其中,库区东北部区县肉牛结核病、布鲁菌病的阳性检出率均为最高,分别为1.83%、1.14%;3种肉牛养殖规模条件下,个体散养农户牛群结核病、布鲁菌病的阳性检出率均为最高,分别为2.21%、2.94%;所调查的3个年龄段牛群中,19月龄以上牛群结核病、布鲁菌病的阳性检出率最高,分别为2.91%、4.85%。 相似文献
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"已实现"波动率是一种全新的金融波动率测量方法。"已实现"波动率在理论上没有测量误差的无偏估计量,在实证建模方面比其他模型更易于估计参数,同时最优频率的选取对于"已实现"波动率的测量精确度是很重要的。 相似文献
110.
A herd of 15 Chinese elephants attracted international attention during their 2021 northward trek, motivating the government to propose establishment of an Asian elephant national park. However, planning is hampered by a lack of genetic information on the remaining populations in China. We collected DNA from 497 dung samples from all 5 populations encompassing the entire range of elephants in China and used mitochondrial and microsatellite markers to investigate their genetic and demographic structure. We identified 237 unique genotypes (153 females, 84 males), representing 81% of the known population. However, the effective population size was small (28, range 25–32). Historic demographic contraction appeared to account for low haplotype diversity (Hd = 0.235), but moderate nucleotide and nuclear diversity (π = 0.6%, He = 0.55) was attributable to post-bottleneck recovery involving recent population expansion plus historical gene exchange with elephants in Myanmar, Lao PDR, and Vietnam. The 5 populations fell into 3 clusters, with Nangunhe elephants differing consistently from the other 4 populations (FST = 0.23); elephants from Mengyang, Simao, and Jiangcheng belonged to a single population (henceforth, MSJ), and differed from the Shangyong population (FST = 0.11). Interpopulation genetic variation reflected isolation by distance and female-biased dispersal. Chinese elephants should be managed as 2 distinct units: Nangunhe and another combining Shangyong and MSJ; their long-term viability will require restoring gene flow between Shangyong and MSJ, and between elephants in China and neighboring countries. Our results have the potential to inform conservation planning for an iconic megafaunal species. 相似文献