鸡胚对小鼠生长和免疫力的影响

实验以 3 0龄小白鼠为研究对象 ,分别采用鸡胚尿囊液和生理盐水 (对照 )灌胃 3 0d .结果证明 ,鸡胚尿囊液具有明显的促进生长作用 ( p <0 .0 1) ,促进生长效果达 12 .1% .鸡胚尿囊液和胚体混悬液对小鼠具有很好的提升作用 .试验证明 :鸡胚尿囊液和胚体混悬液不仅可以增加小鼠吞噬细胞数量 ,提高其吞噬能力 ( 0 .4mL/ (只·日 )灌胃时 ,p <0 .0 1) ,而且可以提高T淋巴细胞的数量 ( 0 .2mL/只 ,0 .4mL/ (只·日 )灌胃时 ,p <0 .0 1) .就提高小鼠免疫能力而言 ,以 10d龄的鸡胚尿囊液和胚体悬液 ,剂量为0 .4mL/ (只·日 )效果最好 .有关鸡胚尿囊液在功效学方面的作用 ,有待进一步研究 .     

玉米幼胚培养的研究

以20个基因型的玉米自交系幼胚为材料，通过培养均获得愈伤组织。研究结果表明，基因型、培养基成分、胚的大小、光等均影响培养效果。     

Effect of UPP on the expression of VEGF and its receptors in mouse uterus during peri-implantation

On day 3 of gestation ,one uterine horn of female pregnant mouse was injected intraluminally with 5 μL 0.1μg/mL lactacystin,a specific inhibitor of ubiquitin-pro-teasome pathway (UPP),while the contralateral horn served as control ,Animals were sacrificed by cervical dislocation on day 5,6,7 of gestation ,respectively,Then the number of implanted embryos in each uterine horn was calcuated,and the expression of VEGF and its receptors was examined,The data showed that the number of implanted embryos was decreased significantly after treatment with lactacystin ,The results of RT-PCR and Western blot indicated that expression of VEGF and its receptors at mRNA and protein levels was significantly decreased in the treated uterus,menawhile,the expression of HIF-1α(the α subunit of HIF ,a transcrip-tional factor of VEGF) was reduced at both mRNA and protein levels,These data suggested that the effect of UPP on VEGF expression was realized through regulating HIF-1α expression .In addition ,UPP is likely to take part in the modulation of VEGF receptors expression ,These changes may be one of the reasons for the reduction of implanted embryos.     

Positional variation of antipodal cells in polyembryonic rice ApⅢ before and after fertilization

The variation in the position of antipodal cells before and after fertilization in polyembryonic rice strain ApⅢ was studied by using conventional sectioning technique. It was shown that initially the three antipodal cells lie at the chalazal end of the young embryo sacs. Along with the development of embryo sac, the antipodal cells proliferate into a multicellular structure containing up to about 20 cells. Most of the cells migrate to its dorsal side when the embryo sacs turn into mature. In a few embryo sacs the antipodal cells are situated in the positions adjacent to the egg apparatus at the micropylar end, while in other sacs, they spread from the midst of the embryo sac to the micropylar end clinging to the nucellar tissue. Furthermore, it is reported for the first time that cells of some egg apparatus or proembryos disorganize when antipodal cells lie at the micropylar end, indicating that the function of the antipodal cells may vary during the embryogenesis in rice ApⅢ.     

《孔子诗论》与先秦文学鉴赏的萌芽

上博简《孔子诗论》对《诗经》的解说注意体会作品所蕴含的内在情感，注意阐发论者所获得的审美感悟，注意揭示诗篇所展现的风俗民性。这些显示出《孔子诗论》已具有文学鉴赏的某些属性。但同时，和先秦其它论著中鉴赏《诗经》的论述一样，《孔子诗论》对《诗经》审美、文化价值的把握又是直觉性的和不自觉的，因此它们都只能算是文学鉴赏的萌芽。《孔子诗论》是这些处于萌芽状态的文学鉴赏的典范。     

脯氨酸和硝酸银对甜玉米幼胚愈伤组织诱导与分化的影响

以甜玉米TD08、TD10的幼胚为外植体,利用不同培养基对其幼胚进行愈伤组织诱导,着重探讨脯氨酸对玉米愈伤组织诱导的影响,同时检验硝酸银是否能替代脯氨酸在玉米愈伤组织诱导中所起的作用.结果表明,脯氨酸有利于玉米愈伤组织诱导且愈伤质量较好;硝酸银不能替代脯氨酸在玉米愈伤组织诱导及分化中所起的作用.     

向日葵未成熟胚体细胞胚胎发生的研究

以不同基因型向日葵未成熟胚为材料,从幼胚的大小、蔗糖浓度、碳水化合物(糖类)、激素(2,4-D和6-BA)等方面探讨了向日葵体细胞胚胎发生的影响因素.结果表明:幼胚≤2 mm时,体细胞胚胎发生频率较高(45.5%);体细胞胚胎发生的适宜培养基为MS 0.4 mg/ L 2,4-D 120 g/ L蔗糖.     

New developments in the biological functions of lysophospholipids

Lysophospholipids have long been recognized as membrane phospholipid metabolites, but only recently has their role as intercellular signaling molecules been appreciated. Two of the best-studied lysophospholipids, LPA and S1P, signal through cognate G-protein-coupled receptors to activate many well-known intracellular signaling pathways, leading to a variety of biologically important cell responses. Lysophospholipids and their receptors have been found in a wide range of tissues and cell types, indicating their importance in many physiological processes, including reproduction, vascular development, cancer and nervous system function. This article will focus on the most recent findings regarding the biological functions of lysophospholipids in mammalian systems, specifically as they relate to health and disease. Received 5 April 2006; received after revision 22 June 2006; accepted 9 August 2006     

Sea urchin embryo as a model for analysis of the signaling pathways linking DNA damage checkpoint,DNA repair and apoptosis

DNA integrity checkpoint control was studied in the sea urchin early embryo. Treatment of the embryos with genotoxic agents such as methyl methanesulfonate (MMS) or bleomycin induced the activation of a cell cycle checkpoint as evidenced by the occurrence of a delay or an arrest in the division of the embryos and an inhibition of CDK1/cyclin B activating dephosphorylation. The genotoxic treatment was shown to induce DNA damage that depended on the genotoxic concentration and was correlated with the observed cell cycle delay. At low genotoxic concentrations, embryos were able to repair the DNA damage and recover from checkpoint arrest, whereas at high doses they underwent morphological and biochemical changes characteristic of apoptosis. Finally, extracts prepared from embryos were found to be capable of supporting DNA repair in vitro upon incubation with oligonucleotides mimicking damage. Taken together, our results demonstrate that sea urchin early embryos contain fully functional and activatable DNA damage checkpoints. Sea urchin embryos are discussed as a promising model to study the signaling pathways of cell cycle checkpoint, DNA repair and apoptosis, which upon deregulation play a significant role in the origin of cancer. Received 10 April 2007; accepted 23 April 2007     

早期胚胎玻璃化冷冻保存技术研究进展

胚胎冷冻技术是胚胎移植真正走向商业化应用的关键环节,并受到广泛的关注,而玻璃化冷冻不仅具有操作时缩短、而且方法简易、不需要昂贵的设备,容易在生产中推广使用,因而日益受到人们的重视。本综述阐明了胚胎玻璃化冷冻原理,讨论了抗冻保护剂及其选择原则,比较了玻璃化冷冻技术各种方法及其优缺点,分析胚胎玻璃化冷冻的影响因素,展望了玻璃化冷冻技术的应用前景。