神农香菊花蕾的组织培养

1植物名称神农香菊(Dendranthema indicum var.aromaticum). 2材料类别花蕾. 3培养条件以MS为基本培养基.愈伤组织诱导培养基:(1)MS 6-BA 2 mg·L-1(单位下同) NAA 1;芽分化培养基:(2)MS 6-BA 2 NAA 0.2,(3)MS 6-BA 0.2 NAA 0.02;生根培养基:(4)1/2MS NAA 0.1,(5)1/2MS IBA 0.3,(6)MS.上述培养基均添加3%蔗糖、0.5%琼脂,pH为5.8.培养温度为25～28℃,光照度1 600～2 000 lx,光照时间14 h·d-1,湿度70%～80%.     

三疣梭子蟹不同组织同工酶的分析

采用垂直板状聚丙烯酰胺凝胶电泳技术 ,分析了三疣梭子蟹 (Portunustriuberbuculatus)雌性成体心脏、鳃、肌肉、眼睛、肝胰腺和卵巢 6种组织中的 1 0种同工酶 (ADH、MDH、ME、LDH、α AMY、GDH、SOD、SDH、EST和GOT)的分化表达模式 ,并对各种酶的同工酶位点表达及酶谱表型进行了分析。结果显示 ,三疣梭子蟹的同工酶系统具有明显的组织特异性。     

PEG对甘薯愈伤组织淀粉酶活性的影响

用聚乙二醇 (PEG) 6 0 0 0对甘薯愈伤组织进行处理后观察到其所含淀粉酶的活性变化。这些变化随PEG的浓度不同 ,处理时间长度不同而有显著差异。低浓度的PEG(0 5 %、 1% )处理愈伤组织其淀粉酶活性变化的幅度较小 ;而高浓度 (8% )的PEG处理所引起的淀粉酶活性变化幅度较大 ;这一结果显示了PEG对甘薯愈伤组织淀粉酶的调节作用。     

GFP-mTn融合蛋白对蓝猪耳生活细胞微丝骨架的标记

用农杆菌介导法将嵌合基因GFP-mTn(mTn是微丝结合蛋白Talin的微丝结合域,可以显示活体细胞中微丝的结构)导入蓝猪耳。经激光共聚焦显微镜观察了转基因植株的各种不同组织中融合蛋白的表达和分布情况。在叶片的表皮细胞、保卫细胞、根部的皮层细胞中有融合蛋白的不同程度表达。但仅在保卫细胞中微丝标记状况良好,显示基因表达的组织特异性。经光诱导处于开放态的气孔的保卫细胞微丝呈网状结构,在细胞内无规则分布;经黑暗诱导处于关闭态的气孔保卫细胞中微丝束沿保卫细胞纵轴排列,呈卷曲状分布,并观察到螺旋和环状的微丝结构。在转基因植株的其他部位,例如茎表皮细胞、根毛细胞和花粉粒中,未检测到目的基因的表达。本研究获得的转基因植株为研究气孔运动过程中微丝动态变化提供了有用的材料。     

中国人胃癌染色体17q21区域基因遗传不稳定性研究

To investigate microsatellite instability (MSI) and loss of heterozygosity (LOH) of locus D17S396, D17S579 and D17S855, and their effect on the expression of nm23H1 and BRCA1 of gastric cancer, which would provide experimental basis for clinical treatment and prognosis analysis of gastric cancer. DNA was extracted from paraffin-embedded materials. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to analyze MSI and LOH. Expression of nm23H, and BRCA1 was detected by Envision immuno-histochemistry and Leica-Qwin computer imaging techniques. In the forty cases of gastric cancer, the frequency of MSI, LOH and nm23H1 protein were 20.00%, 17.50% and 55.00% respectively at locus D17S396, while at locus D17S579, the frequency of MSI, LOH and BRCA1 protein were 22.50%, 15.00% and 37.50% respectively; at locus D17S855, the frequency of MSI, LOH and BRCA1 of thirty-seven cases were 18.92%, 18.92%, 37.84% respectively. In tumor node metastasis (TNM) staging, at locus D17S396, D17S579 and D17S855, MSI in stages I + II appeared more frequently than that in stages III + IV, while LOH appeared the contrary tendency. In the group of metastasis of gastric cancer, MSI had a less frequency (5.00%) than that with no metastasis (35.00%, P < 0.05) at locus D17S396, but LOH appeared more frequently (30.00%) than that with no metastasis (5.00%, P < 0.05). At locus D17S579, MSI had an increasing tendency with the degree of tumor differentiation (50.00% in high differentiation cases, 20.00% in middle differentiation cases, and 0% in low differentiation cases, P < 0.05). The frequency of nm23H1 and BRCA1 protein in stages TNM I + II was higher than that in stages TNM III + IV; and that in higher differentiation cases was higher than in poor differentiation cases. The frequency of nm23H1 protein in the group of metastasis (30.00%) was less than that with no metastasis significantly (80.00%, P<0.01). The frequency of nm23H1 protein in the group positive to MSI (87.50%) was higher than that in the group negative to MSI (46.88%, P < 0.05). However, nm23H1 protein in group positive to LOH (14.29%) was lower than that in the group negative to LOH (63.64%, P < 0.05). The frequency of BRCA1 protein in the group positive to MSI (66.67%) was more than that in the group negative to MSI (29.03%, P < 0.05). The results of experiments indicate that MSI and LOH may separately control the development of sporadic colon cancer with different pathways. MSI may be an early period molecule marker for sporadic colon cancer, enhanced expression of nm23H1 protein can effectively inhibit colon cancer metastasis and improve prognosis of sporadic colon cancer patients. By comparison, LOH mostly arises in the late period of sporadic colon cancer and endows a high aggressive and poor prognostic phenotype. nm23H1 protein could effectively restrain gastric cancer metastasis and development; and BRCA1 protein could restain tumor from becoming lower differentiation.     

第五届海峡两岸细胞生物学研讨会即将在福建召开

海峡两岸细胞生物学研讨会是由中国科学院姚龛院士与台湾国家卫生研究院吴成文院长于1996年组织发起的双边学术会议,已召开了四届。目的是为了交流两岸细胞生物学研究的最新成果,进一步促进海峡两岸生物学科技教育的合作与发展。会议秉着促进两岸科学家交流与合作,学术自由的原则,参会双方均以科学家身份参加。会议每两年召开一次,由台湾、大陆轮流组织召开。     

影响食肉目动物能量学的生态因子

在食肉目的62种动物中,体重的变异可以解释基础代谢率86.8%的变化。当栖息基底、食性、生境和纬度等4个因素与体重合起来一起分析,则可以解释基础代谢率98.7%的变化,即这些生态和行为因子可以解释代谢率残差变异的81.1%。身体成分也是影响基础代谢率的另一个因素,可以解释一些大型树栖种类的较低的代谢率。除体重因素外,导致真兽类基础代谢率变异的主要原因是:当生态因素适合时,高水平的能量消耗可以促进动物的高繁殖输出,而动物的某些习性和生存环境则会要求低能量消耗,从而使繁殖率降低。当以科为单元进行分析时,对结果没有影响。生理参数与分类单元之间大多数的相关性反映了生态和行为因素与分类系统之间的一种粗略的相关关系。除非系统学可以反映动物的生态学和行为学,否则系统学不能决定动物适应性特征的状态     

组织工程的新来源--原始生殖细胞

原始生殖细胞具备发育全能性,因数量较多,所以进行分离克隆将优于数目较少的内细胞团细胞。可作为组织工程的新来源：原始生殖细胞是研究基因组印迹与胚胎早期发育关系的最佳材料,还是研究生殖细胞发育分化的体外模型和研究转基因动物遗传操作的有效载体．具有广泛的应用前景。     

"光合作用"一课的互动教学设计

通过初中阶段的学习,学生已经掌握了光合作用所需的条件、产物和概念。高中是在初中原有知识基础上的拓展和加深,主要侧重于光合作用的过程和本质,并在此基础上归纳出光合作用的重要意义,以达到一种理性认识。但光合作用是一种非常复杂的生理过程,科学家用了200多年的时间经过无数次的实验才对光合作用的过程有了比较清楚的认识,因此,在组织教学时,教师可以有目的地选取科学家研究光合作用的经典实验。再现探索光合作用的过程,让学生参与到知识的发生过程中,使他们既掌握了相关的知识,又可以学会科学的实验方法,并培养了他们研究性学习的能力。     

花生基因工程

建立花生遗传转化和高效植株再生系统是花生基因工再生技术和基因转化体系的完善,已获得抗病、抗虫和提高品质的转基因花生植株,取得了突破性进展.农杆菌介导法和微弹介导法是花生基因工程的主要方法.