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91.
将含高滴度小反刍兽疫病毒的新鲜病料研磨后接种VERO DS细胞系进行病毒分离,出现细胞病变后连续传代,取3代以上培养物,进行RT-PCR和间接免疫荧光试验及生长曲线测定。生长曲线测定分别以0.01和0.1 MOI接种VERO DS细胞,每隔12h测定病毒滴度,连续培养168h,绘制病毒生长曲线,分析生长特性。结果显示,病料接种细胞72h后,出现细胞病变,经RT-PCR和间接免疫荧光试验鉴定为小反刍兽疫病毒?;生长特性研究显示,0.01和0.1 MOI两种病毒接种量,病毒滴度最高均为106 TCID50左右,但峰值出现时间和下降速度存在差异,0.01 MOI接种量出现峰值晚,但是维持高滴度时间较长。本文成功分离一株小反刍兽疫病毒,并对两种接毒量的生长特性差异进行了初步分析,为探索该病毒培养方法和收毒时间提供了借鉴。 相似文献
92.
2014年5月~2015年2月,采用全事件取样法和扫描取样法(scan sampling method)对人工圈养的8只紫貂进行行为学观察,定义了休息、运动、采食、排泄、警戒以及其他行为等行为谱。通过对雌雄紫貂在不同季节行为节律研究发现:除了睡眠行为、卧息行为和玩耍行为外,其他行为在时间分配上均表现出雄性高于雌性,卧息行为和其他行为时间分配雌雄之间差异性显著(P<0.05)。人工圈养紫貂行为的日节律表现为19:00到次日5:00处于活动高峰期,日行为具有一定节律性。不同季节紫貂的日节律表现为夏季最高,冬季最低。 相似文献
93.
Effects of dietary energy level on lipid metabolism‐related gene expression in subcutaneous adipose tissue of Yellow breed × Simmental cattle 下载免费PDF全文
Haibo Zhang Xiangfei Zhang ZhiSheng Wang Xianwen Dong Cui Tan Huawei Zou Quanhui Peng Bai Xue Lizhi Wang Guozhong Dong 《Animal Science Journal》2015,86(4):392-400
This study was conducted to estimate the effect of dietary energy level on lipid metabolism‐related gene expression of subcutaneous adipose tissue in Yellow breed × Simmental cattle. The experiment was conducted for 60 days. The results showed that final weight, average daily gain, average backfat thickness, (testicles + kidney + pelvic) fat percentage and subcutaneous fat percentage in the high and medium energy groups were significantly higher than in the low‐energy group but that the feed conversion ratio was significantly lower. The glucose, triglycerides, cholesterol, high‐density lipoprotein and low‐density lipoprotein in the high‐energy group were significantly higher than in the low‐energy group. With dietary energy increasing the activities of lipoprotein lipase (LPL), fatty acid synthase (FAS) and acetyl‐CoA carboxylase (ACC) significantly increased, whereas hormone‐sensitive lipase (HSL) and carnitine palmitoyltransferase‐1 (CPT‐1) significantly diminished. Peroxisome proliferator‐activated receptor γ (PPARγ), LPL, FAS, sterol regulatory element binding protein 1 (SREBP‐1), ACC, stearoyl‐CoA desaturase (SCD) and adipocyte‐fatty acid binding proteins (A‐FABP) gene expression were significantly increased by dietary energy increasing, and HSL and CPT‐1 gene expression were significantly decreased. These results indicated that with dietary energy increasing, the subcutaneous fat accumulation mainly increased due to adipose tissue lipogenic gene expression and decreased lipolytic gene expression. 相似文献
94.
Evaluation of embryonic age and the effects of different proteases on the isolation and primary culture of chicken intestinal epithelial cells in vitro 下载免费PDF全文
Chao Yuan Qiang He Jun‐ming Li Mahmoud Mostafa Azzam Jian‐jun Lu Xiao‐ting Zou 《Animal Science Journal》2015,86(6):588-594
The present study evaluates the effects of embryonic age and proteolytic enzymes on the isolation and primary culture of chicken enterocyte and to establish an effective technique for chicken intestinal epithelial cell (IEC) cultivation. Fourteen‐day‐old, 16‐day‐old and 18‐day‐old embryos (average weight: 52.23 ± 0.76 g, 50.86 ± 0.99 g, 48.98 ± 1.03 g) were the source for preparation of enterocyte culture, and trypsin‐ethylene diamine tetraacetic acid, collagenase, thermolysin and combination of collagenase and thermolysin were used for digestion medium. Optimal culture protocols were determined by qualitative assays of proliferation. Cells isolated by using 14‐day‐old embryo and collagenase obtain the best attachment and growth in culture, and the production of continuously growing IEC cultures. Thus, we conclude that the use of collagenase as a dissociating enzyme and 14‐day‐old embryo as a source can be advantageously applied to the isolation of chicken IEC and this method may be useful for various applications and basic studies of the intestinal tract concerning such objects as physiology, immunology and toxicology. 相似文献
95.
用水稻微卫星引物进行竹子分子系统学研究初探 总被引:27,自引:0,他引:27
竹子和水稻在进化上有较近的亲缘关系 ,本文利用水稻的微卫星引物对竹子的分子系统学进行了初步研究。与传统的分类结果不同 ,研究发现巴山木竹属是与青篱竹属相关属分化较大的 1个竹种 ,同时也证实了巴山木竹属作为 1个单独的属是成立的。研究也明确了茶秆竹的分类学位置。本研究从 1个不同的层面对青篱竹属相关属及属下一些竹种的关系提供了 1个新的研究结果 ,为利用现代分子生物学技术对广义青篱竹属的系统学研究提供了 1个借鉴。同时本研究对开展竹子的分子生物学研究提供了 1个崭新的思路和方法 相似文献
96.
97.
Zhu YQ Wu C Li HB Zou XM Si XK Hu FZ Yang HZ 《Journal of agricultural and food chemistry》2007,55(4):1364-1369
A series of pyrazolo[5,1-d][1,2,3,5]tetrazin-4(3H)one derivatives were designed, synthesized, and evaluated for their herbicidal activities where some of these compounds provided >80% control of Brassica campestris at 10 microg/mL. Quantitative structure-activity relationship studies were performed on these compounds using physicochemical parameters (electronic, Verloop, or hydrophobic) as independent parameters and herbicidal activity as a dependent parameter, where herbicidal activity correlated best (r > 0.8) with physicochemical parameters in this set of molecules. The herbicidal activity against B. campestris was mainly affected by the molar refractivity (MR) for R1, Taft (Eso) for R2 or R6, Verloop (Lm) for R3 or R5, and electronic parameters (Hammett's constants) for R4. The optimal MR for herbicidal activity is 0.95. The herbicidal activity against Echinochloa crus-galli was mainly related with the substituents' hydrophobic parameter. The optimal pi parameters for R1 and R4 for herbicidal activity are 0.72 and 0.68, respectively. In general, these compounds showed greater herbicidal activity toward B. campestris than E. crus-galli. 相似文献
98.
花绒寄甲是寄生天牛的重要林木天敌昆虫,为了解花绒寄甲在林间的寄生防治效果,通过林间释放花绒寄甲(成虫、卵卡)来寄生松褐天牛,根据松褐天牛被寄生率和虫口减退率,研究花绒寄甲对松褐天牛的防治效果。结果显示,2019年校正虫口减退率平均值为46.20%,寄生率高于50%的占66.7%;2020年防治效果为 33.18%,寄生率为 34.91%,由此可见,释放花绒寄甲对松林松褐天牛防治效果较明显,寄生情况良好,治理区域内松褐天牛数量有所减少,对松褐天牛危害区具有较好的种群抑制效果。 相似文献
99.
Li Yanan Zhang Tengzi Zhou Yongbin Zou Xiaoming Yin You Li Hui Liu Liying Zhang Songzhu 《European Journal of Forest Research》2021,140(5):1039-1048
European Journal of Forest Research - Ectomycorrhizal fungi (EMF) can enhance drought resistance of host plants by increasing nutrient and water absorption. Calcium (Ca) plays a central role in... 相似文献
100.