糯质高梁杂种优势及配合力的分析

糯质高粱杂种一代存在明显的杂种优势,以穗粒重的优势最强;杂交双亲和中亲值对杂种一代的性状表现有不同程度的正向影响;除不育系间的穗粒重、一级分枝数的一般配合力和穗长的特殊配合力不显著外,其余性状存在极显著差异;株高、穗长、千粒重和一级分枝数在遗传表现中加性基因效应占主导地位,而穗粒重和穗粒数则以非加性基因效应为主。     

网络数据库中数据完整性约束的实现

主要讨论网络数据库中数据完整性约束及其如何实施企业业务规则,并以SQLServer和PowerBuilder为例,介绍了数据完整性约束的实现技术。     

育成期雄性幼貉日粮适宜蛋白质和能量水平的研究

选用健康乌苏里幼公貉63只,随机分为7组(每组9只)。1～4组用以探讨适宜蛋白质水平,其蛋白质水平分别为31.54%、36.39%,40.37%和43.53%;5-7组用以探讨适宜能量水平,其能量水平分别为19589.78,21860.94和22600.04k J/kg。试验分育成前期和冬毛生长期两个阶段进行,饲喂同一营养水平的日粮。结果表明,育成前期饲喂蛋白质水平为36.39%的日粮,可获得理想的体重、体长及经济效益。 冬毛生长期,日粮蛋白质水平在31.54%～43.53%范围内,对幼貉的体重和体长无显著影响。育成期以饲喂能量水平为21860.94～22600.04 k J/kg的日粮为宜。育成前期适宜的蛋能比为16.1～16.6,冬毛生长期为14.0～14.4。     

强广义连续格的完全链表现

建立强广义连续格的完全链表现定理 ,它包括前人关于完全分配格以及传统连续格的已知结果作为特例     

应用均匀设计研究电场刺激及培养因素对甘蓝叶原生质体分裂频率的影响

应用均匀设计法探讨了电场刺激及培养因素对甘蓝叶原生质体分裂频率的影响。结果表明 ,电场方向和强度强烈地影响细胞分裂频率。培养成分对细胞分裂频率均有不同程度的影响。均匀设计能筛选最优的植物原生质体培养条件或培养基。结合“回归 -通径”分析 ,有效地综合评判和研究了各培养成分对原生质体分裂频率的作用     

结构阻尼系统的一种子结构综合方法

本文对结构阻尼系统提出一种模态综合方法,该方法特别适合于部件对接界面自由度较少情况下的结构综合.给出了一个算例来说明方法的有效性.     

Activities of biotransformation enzymes in pheasant (Phasianus colchicus) and their modulation by in vivo administration of mebendazole and flubendazole

Basal activities of certain pheasant hepatic and intestinal biotransformation enzymes and modulation of their activities by anthelmintics flubendazole (FLBZ) and mebendazole (MBZ) were investigated in subcellular fractions that were prepared from liver and small intestine of control and FLBZ or MBZ treated birds. Several oxidation, reduction and conjugation enzyme activities were assessed. In the liver, treatment of pheasants by FLBZ or MBZ caused very slight or no changes in monooxygenase activities and conjugation enzymes. More significative changes were detected in small intestine. Metyrapone and daunorubicin reductase activities were increased by both substances in the liver. This is the first evidence that certain benzimidazoles modulate reductases of carbonyl group. With respect to the relatively slight extent of the changes caused by FLBZ or MBZ we can assume that repeated administration of therapeutic doses of both FLBZ and MBZ has probably no serious influence on pheasant biotransformation enzyme system.     

Effect of gonadotropin-releasing hormone analogue on human breast cancer cell line in vitro

AIM: To investigate the effects of gonadotropin-releasing hormone (GnRH) analogue on the growth of breast cancer cell lines MCF-7 and MDA-MB-231 in vitro and to explore the related mechanisms with PI3K/Akt or ERK/MAPK pathways. METHODS: The proliferation of human breast cancer cell lines MCF-7 and MDA-MB-231 treatment with triptorelin was detected by MTT assay and the distribution of the cell cycle was determined by flow cytometry. The phosphorylation of the ERK1/2 and Akt was evaluated by Western blotting. RESULTS: Triptorelin inhibited the proliferation of MCF-7 cells at concentration of 10^-5 mol/L after treated for 192 h or at concentration of 10^-4 mol/L after treated for 168 h and 192 h. Triptorelin inhibited the proliferation of MDA-MB-231 cells at concentration of 10^-4 mol/L after treated for 192 h (P<0.05).Treatment with triptorelin for 192 h at concentration of 10^-4 mol/L had no statistical significance effect on phosphorylation of ERK1/2 and Akt(P>0.05).CONCLUSION: Inhibitory effect of GnRH analogue triptorelin on human breast cancer cells is not just the connection with the down-regulation of pituitary hormone, but also a direct inhibitory effect. The role may not be involved in the activation of ERK/MAPK and PI3K/Akt signaling pathways.     

Role of kisspeptin/GPR54 signaling pathways in prompting formation of precocious puberty

AIM: To explore the role of kisspeptin/GPR54 signaling pathway in the pathogenesis of precocious puberty based on female precocious puberty rat model induced by the single dose of danazol. METHODS: Female SD rats aged 3 d were randomly divided into normal group, vehicle group and model group. On the 5th day, the model rats were given a single subcutaneous injection of danazol with ethanol and ethylene glycol mixture. All rats were executed on 15 d, 25 d, 30 d, 35 d and 40 d, and the samples were collected to observe the sexual organ development. The levels of E₂, FSH and LH in peripheral blood were measured by ELISA. The Kiss-1 mRNA expression of Kiss-1, GPR54 and GnRH in hypothalamus was detected by real-time PCR. The kisspeptin expression in rat hypothalamus was observed by immunofluorescence. RESULTS: The time for puberty onset and sexual maturation in the model rats was significantly earlier than that in normal group and vehicle group. On days 25 and 30, the levels of peripheral sex hormones and uterine coefficients in model group were significantly higher than those in normal group and vehicle group. On days 25 and 30, the ovarian morphological development in the model rats was significantly earlier than that in normal group. On day 25, the mRNA expression of hypothalamic Kiss-1 and GnRH, and kisspeptin expression of hypothalamic arcuate nucleus in the model rats significantly increased compared with normal group and vehicle group. On day 30, kisspeptin expression of hypothalamic arcuate nucleus in the model rats decreased compared with normal group and vehicle group. On day 35, the mRNA expression of Kiss-1 and GnRH in the model rats decreased compared with normal group and vehicle group. The mRNA expression of GPR54 had no obvious difference among all groups. CONCLUSION: The Kiss-1 mRNA and kisspeptin expression in the model rats with precocious puberty is significantly increased in the hypothalamus during onset of puberty, suggesting that kisspeptin is an initiating factor for precocious puberty. Kisspeptin/GPR54 signaling pathway may play an important role in the occurrence of precocious puberty.     

Development of cell model of polymer/liquid crystal and effect of their elasticity on adhesion of rBM-MSCs

AIM: To develop the cell model of polymer/liquid crystal and to study the effect of their elasticity on the adhesion of rat bone marrow mesenchymal stem cells (rBM-MSCs). METHODS: Using the method of solvent evaporation induced phase separation, the cell model of polymer/liquid crystal was constructed. The surface morphology and phase separation structure were determined by polarized optical microscopy (POM), scanning electron microscopy (SEM) and small angle X-ray scattering (SAXS). rBM-MSCs were separated and expanded by adherent culture. The surface markers of rBM-MSCs were detected by flow cytometry. The cells were induced to osteogenic differentiation and adipogenic differentiation for 2 weeks. After 3 passages, the cells were divided into 4 groups, including total PU control group, 10% membrane group, 30% membrane group and 50% membrane group. The cells were then incubated with rhodamine phalloidin for cytoskeleton staining and were observed under the confocal laser scanning microscope after cultured for 24 h. RESULTS: The cell model of polymer/liquid crystal was constructed successfully using the method of solvent evaporation induced phase separation. Flow cytometry results showed that the rBM-MSCs positively expressed CD29, CD44 and CD90, and negatively expressed CD34 and CD45. After stained with alizarin red S and oil red O, the calcium nodule and lipid droplets in rBM-MSCs were observed obviously. The cytoskeleton staining result indicated that the area in total PU control group, 10% membrane group and 30% membrane group were greater, and the actin microfilaments were also clearer than that in 50% membrane group. CONCLUSION: The cell model with suitable content of liquid crystal made a contribution to the rBM-MSCs' adhesion, but too much liquid crystal inhibits cell adhesion.