基于动物福利视角的规模化奶牛养殖场经济效应分析

本研究遵循动物福利"5F"原则,结合150家规模化奶牛养殖场实地调研数据,构建奶牛场动物福利评价体系,测度动物福利水平,并进一步建立嵌入动物福利水平测度值的规模化奶牛养殖场收入函数,验证关联效应.结果表明:生理福利和环境福利是影响我国规模化奶牛养殖场动物福利的最重要的2个维度,受访的规模化奶牛养殖场生理福利和环境福利的...     

白菜亚硝酸还原酶基因BcNiR的克隆及表达分析

 以白菜品种‘苏州青’自交系叶片cDNA为模板, 采用RT-PCR、3′RACE和5′RACE技术, 获得了编码亚硝酸还原酶基因(NiR) 的cDNA全序列1 852 bp, 包含有1 749 bp的开放阅读框, 编码583个氨基酸, 命名为BcNiR。所推导的氨基酸序列与拟南芥NiR1、烟草nii2编码的氨基酸序列具有较高同源性, 分别为83%和76%。生物信息学分析表明, BcNiR具有完整的NiR蛋白结构, 含血红素蛋白β - 化合物区域, 一个明显的西罗血红素siroheme结合位点和4Fe-4S区域, 可以在SWiSS-MODEL数据库中搜索到与之相近的三维结构。RT-PCR结果显示, 该基因在叶片中的表达量远远高于根系, 在以0、10、20、30、40 mmol·L ^{- 1}硝态氮各分别处理0、2、4、6、8、12 h的试验中, 30 mmol·L ^-1处理4 h可使BcNiR的表达量达到最大; 5和10 mmol·L ^{- 1}铵态氮处理试验表明, 高浓度的铵抑制该基因的表达。     

Impact of serial activation of embryonic pax2 and WT1 genes on transdifferentiation of renal tubular epithelial cells

AIM: To investigate the mechanisms of transdifferentiation of renal tubular epithelial cells by the observation of serial activation of embryonic pax2 and WT1 genes in chronic renal failure model of 5/6 nephrectomized injury. METHODS: Embryo of mice, cultured renal tubule cells and chronic renal failure rat model of 5/6 nephrectomized injury were established. The expressions of paired Box gene (pax2) and Willm’s tumor gene (WT1), as well as α-smooth muscle actin (α-SMA), a phenotype of mesenchymal cells, were detected by RT-PCR and immunohistochemistry techniques. RESULTS: (1) Expressions of pax2 and WT1 mRNA began at 11.5 d and 14 d of embryo and increased gradually, and expression in trace quantity at 2 weeks after birth. Immunohistochemistry analysis revealed that WT1 only expressed in the glomerular podocytes and expressions of pax2 and WT1 in adult renal tubular cells were negative. (2) Deno-expression of pax2 and WT1 in some tubular cells appeared at week 2 and peaked at week 4 in 5/6 nephrectomized rats, both showing a same trend of expression. However, pax2 showed another peak at week 10 afterwards. (3) Re-expressions of pax2 and WT1 in TEC at 0.5 and 24 h after treated with IL-1α (10 μg/L) or AngII (10-9 mol/L) were observed respectively, followed by upregulation of α-SMA expression, and mesenchymal cells characters were shown. The effects were inhibited by Ang II receptor 2 antagonist and WT1 antibody, respectively. CONCLUSION: Adult renal tubule cells acquire re-activation of embryonic pax2 and WT1 genes and phenotypes of mesenchymes when challenge with certain injuries. Deno-expression of pax2 and WT1 genes closely relates with high concentration of bioactive facors, such as AngII and IL-1, which are involved in the mechanisms of renal tubule cells transdifferentiation.     

Effects of salvianolic acid B on neurons during oxygen/glucose deprivation and reintroduction

AIM: To observe the damage induced in the primary cultured rat cortical neurons by oxygen/glucose deprivation and reintroduction, and to investigate the neuroprotective mechanism of salvianolic acid B (SalB). METHODS: Primary cultured rat cortical neurons were randomly divided into the control group, the model group and the SalB group. The cell model was established by oxygen/glucose deprivation for 3 h followed oxygen/glucose reintroduction for 24 h. The cortical neurons viability was determined by MTT assay. The leakage rate of lactate dehydrogenase (LDH) was measured by chromatometry. The mitochondrial membrane potentials (MMP) and the apoptosis rate were quantitatively analyzed by flow cytometry. The cytosolic free calcium was assessed using LSCM. The morphologic changes of neuronal nuclei were observed by Hoechst 33342 fluorescence staining. RESULTS: Compared to the model group, the cortical neurons viability, the survival rate and the fluorescence value of MMP in the SalB group were obviously increased (P<0.05,P<0.01). In addition, in the SalB group, the leakage rate of LDH, the fluorescence intensity of cytosolic free calcium and the apoptosis rate were significantly lower than those in the model group (P<0.01). CONCLUSION: The neuroprotective mechanism of SalB in the oxygen/glucose deprivation and reintroduction neurons would be due to the fact that SalB maintains the MMP and the calcium homeostasis.     

不同木豆品种的生物学和品质特性比较研究

以广西地方木豆品种为对照,与引进的其他7个木豆新品种进行田间比较试验,评价引进木豆品种的种性和生态适应性.结果表明:不同木豆品种的根、茎、叶、花、荚、籽粒、株型等形态特征,萌芽、生长、开花、生长期、抗病虫性等生长特性以及茎、叶、籽粒的粗蛋白、粗脂肪、粗淀粉含量都有显著差异.根据不同品种的表现:广西品种、非洲品种、缅甸品种、ICPL87119比较适应喀斯特石山区荒地、山地种植,可作为饲料、水土保持、生态保护、薪炭林等用途,ICPH8、IC-PL87091可作蔬菜和粮食用,其中ICPL87091是一个比较有希望的品种.     

中国食糖供求分析与预测

利用预测模型从原料生产的角度,分析了我国食糖供给的变化趋势;然后从居民用糖和工业用糖两个方面,研究了食糖需求的变化;最后从贸易的角度,探讨了我国满足国内食糖供需缺口的可能途径。研究发现：食糖的供给潜力主要在于甘蔗糖方面;需求方面,工业用糖量增长较快,是推动食糖需求增长的主要动力。由于食糖需求增长的速度快于供给的增长,我国食糖的供求缺口有不断增加趋势。为避免食糖体系失衡风险,增加国内食糖供给才是解决我国食糖供求矛盾的最佳途径。     

黑土长缓坡地形与横垄对土壤有机碳空间分异的交互作用

横坡垄作对坡耕地土壤有机碳（soil organic carbon,SOC）流失有一定的阻控作用,但黑土区特有长而缓的地形与横垄对坡耕地SOC空间分异会产生交互作用,而这种交互作用引发的SOC流失风险没引起足够的重视。该研究以典型黑土区黑龙江省黑河市北安分局红星农场为研究区域,2022年在横坡垄作与顺坡水线方向上共布设25个采样点,采用地理探测器模型、单因素方差分析（one-way ANOVA）和Pearson相关性分析,探讨土壤有机碳的空间分异及其交互作用。结果表明,横坡垄作方向上垄沟土壤有机碳含量从坡顶到水线呈现逐渐增大的变化趋势;在垄台从坡顶到水线呈现先增大后减小的变化趋势。顺坡水线方向,土壤有机碳含量在垄沟呈现从上坡到下坡增大的变化趋势;在垄台呈现先增大后减小的变化趋势。由于断垄产生水线,顺坡土壤有机碳含量上坡与下坡仍有显著差异（P＜0.05）。Pearson相关性分析表明, 有机碳与可蚀性K因子呈显著负相关（垄沟和垄台相关系数分别为–0.228和–0.238,P＜0.05）,与碳循环相关的β-葡萄糖苷酶和微生物生物量碳在垄沟呈极显著正相关（相关系数为0.398和0.676,P<0.01）。地理探测器分析表明,顺坡水线对土壤有机碳空间分异的影响最大,其对垄沟和垄台SOC的解释力分别达到61%和52%以上;顺坡水线与其他因子的交互作用共同增强了对土壤有机碳的解释力,尤其是顺坡水线与高程的交互作用最为明显。黑土区坡耕地土壤有机碳空间分异主要受顺坡水线与高程的交互作用,横坡垄作虽然能够拦截径流,但由于长缓坡地形影响产生的断垄会加剧土壤侵蚀诱发的有机碳流失。因此,黑土坡耕地治理需要同时考虑横垄与地形的共同影响,从而实现防蚀的优化效果。     

旱地驱动耙工作部件运动学分析及动态仿真

对旱地驱动耙的工作部件—刀齿进行运动分析。建立运动学模型及仿真模型，探讨了主要参数对耕作过程的影响，为旱地驱动耙的设计和分析提供理论依据。     

汽车综合性能检测站数据库的设计

介绍了汽车综合性能检测站数据库类型、设计、访问技术,论述了车型参数数据库系统的结构、特点和要求等.其结果表明,通过两年多的使用,车型参数数据库是一种有利解决广东省汽车综合性能检测的有效手段,能够更好地满足广东省汽车综合性能检测发展的实际需要,表明了数据库在广东省汽车综合性能检测站中的作用和意义.     

Cloning and Sequence Analysis of Expansin Genes from Litchi chinensis Fruit

Using PCR degenerate primers, designed with reference to the sequences of the conserved amino acids of known expansins, to amplify cDNA fragments in litchi fruit by RT-PCR, two different cDNA fragments, named as Lc-Expl and Lc-Exp2, were cloned. Lc-Expl and Lc-Exp2 was respectively composed of 531 bp encoding 177 amino acids and 537 bp encoding 179 amino acids. Eight cysteine residues and three tryptopban residues, which is supposed to be the characteristics of expansins, are conserved in both Lc-Expl and e-Exp2. In addition, the homology between the two expansins is 71.6% at nucleotide acid sequences and 76.3% at amino acid sequences. The homology of Lc-Expl with Fa-Exp2 or Pp-Expl was 92.7% or 92.1%, but that of Lc-Exp2 with Fa-Exp2 or Pp-Expl was only 77.4% or 76.3% at amino acid sequences.