Evolution of Xanthomonas Gene Content: Gene Gain/Loss History and Species Divergence

Horizontal gene transfer (HGT) plays key roles in the evolution of pathogenetic bacteria,especially in pathogenetic associated genes.In this study,the evolutionary dynamics of Xanthomonas at species l...     

转基因动物应用研究的现状与进展

对转基因动物在提高动物生产性能、异种器官移植和基因治疗方面的研究现状和应用前景进行了较系统全面的概述。提高动物的生产性能包括提高动物的生长速度和产毛性能 ;异种器官移植的机理主要为补体介导的超急排异反应 ,猪是最佳异种器官供体 ;基因治疗在短期内已取得了显著成绩 ,但不是万能的 ;转基因动物在应用方面前景广阔 ,但仍存在一些问题。     

基于GIS和转移矩阵的森林资源动态变化研究

在森林资源林相图数据化改造的基础上,以2003、2010年的资源建档数据为基础,以GIS技术为支持,结合转移矩阵算法,分析和评价了7 a间研究区森林资源面积、蓄积、地类、林种、树种和郁闭度在空间的变化过程和趋势。结果表明,在7 a间,研究区的森林面积呈减少趋势,而蓄积量却不断增加。从地类来看,林地和非林地之间变化明显,林地减少219.20hm2;商品林变化明显,生态公益林相对稳定,树种结构不断优化,郁闭度变化程度较大,森林资源的经营管理水平不断提高,经营初现多元化趋势。说明采用GIS和转移矩阵技术,不但从数量上分析资源的变化情况,而且可以对发生变化的区域进行刻画和演绎,提高森林资源动态变化研究的深度和水平。     

Gene transfer and expression of recombined human proinsulin in hepatoma cells of rats

AIM:To explore the recombined human proinsulin gene containing glucose reaction element (GLRE) expression in transfected CBRH7919 cells. METHODS:The packaged retrovirus encoding genetically modified human proinsulin PLXSN-(GLRE)3-BP-1MpINS3 and PLXSN-(GLRE)3-BP-1MpINS2 were transfected into CBRH7919 cells. Insulin values in cells after transient and steady expression screened by G418 at different glucose levels were detected. Chromosome DNA was isolated from transfected and untransfected cells and polymerase chain reaction (PCR) was performed. PCR products were analyzed by electrophoresis. RESULTS:38 h after transfection, at the glucose levels of 0-25 mmol/L, the levels of insulin produced by cells including PLXSN-(GLRE)3-BP-1MpINS3 were (3.57±0.21)U/L, (5.30±0.20)U/L, (16.27±0.87)U/L, (23.23±1.12)U/L, respectively (P<0.05). One month after transfection, under above glucose levels, insulin values were (3.57±0.21)U/L, (5.30±0.20)U/L, (16.27±0.87)U/L, (23.23±1.12)U/L (P<0.05). CBRH7919 cells including PLXSN-(GLRE)3-BP-1MpINS2 secreted detectable insulin value at the level of 25 mmol/L, they were (2.10±0.23)U/L and (2.05±0.17)U/L, respectively. PCR products of transfected cells showed target band, but control cells did not. CONCLUSIONS:Recombined proinsulin gene was transfected successfully in CBRH7919 cells. The cells combined human proinsulin gene has the ability of producing insulin with increase in glucose concentration in vitro.     

Laparoscopy vs. laparotomy for embryo transfer to produce transgenic goats (Capra hircus)

This study was performed to produce transgenic Korean native goat (Capra hircus) by laparoscopic embryo transfer (ET) to overcome the limitations of ET performed by laparotomy. Transgenic embryos were produced by DNA pronuclear microinjection of in vivo zygotes. The recipient goats were synchronized for estrus by using an introvaginal progesterone devices as a controlled internal drug-releasing insert (CIDR) for 13 days and injection of 400 IU PMSG 48 h before removal of the insert. Embryos were transferred on day 3 and 4 after removal of the insert. Recipient goats were deprived of feed for 48 h, then suspended in a laparotomy cradle at an angle of 45°. After obtaining a sufficient pneumoperitoneum, the laparoscope and forceps were inserted abdominally through 5 mm trocar sleeves. Examination of the ovaries and uterus was performed and then 213 embryos were transferred into the oviducts via the infundibula of 76 recipient goats. To compare pregnancy rates, ET was also performed by laparotomy in 82 recipient goats. The pregnancies in the recipient goats were diagnosed by ultrasound on day 30 after embryo transfer. The pregnancy rate with laparoscopic ET was significantly higher than with ET performed by laparotomy (46.1% vs. 28.6%, p < 0.05). In addition, the pregnancy rates were compared between ovulated and non-ovulated ovaries of the recipient goats in the laparoscopic ET group. No significant difference was observed between the pregnancy rates of ovulated and non-ovulated ovaries (41.3% vs. 33.3%, p < 0.05) suggesting that ET may also be possible in non-ovulated recipients through artificial rupture of Graafian follicles. These results suggest that laparoscopic ET is a highly efficient method for the transfer of goat embryos.     

贵阳市农村劳动力转移研究

以贵阳市为例,对农村剩余农村劳动力转移情况进行了认真调查和总结分析.分析结果发现,贵阳市农村劳动力转移存在相应的服务不足,农民的法律知识短缺,接受的培训不多及掌握的劳动技能有限、收入不高等问题.但是,只要各政府部门齐抓共管,为劳动力转移创造必要的条件,农民工资性收入一定能再上一个台阶.     

Genetics of adult plant stripe rust resistance in four Australian wheats and the French cultivar 'Hybride-de-Bersée'

Long-term resistance to rust diseases depends on the identification and use of durable resistance sources or on the continuing use of new resistances and combinations of genes for specific resistance. These studies include four Australian wheats with intermediate, but inadequate levels of resistance and a French wheat ‘Hybride-de-Bersée’ (‘Bersee’), with reputed durable resistance to stripe rust. Studies of F₂ and F₃ populations from crosses with the susceptible ‘Avocet’ indicated that intermediate levels of adult plant stripe rust resistance in cultivars ‘Harrier’, ‘Flinders’ and ‘M2435’ were inherited monogenically, whereas King possessed two genes for resistance. Cultivars Harrier and M2435 possessed the same gene. Similarly, cvs. King and Flinders carried a gene in common. Like ‘Harrier’ and ‘M2435’, ‘King’ and ‘Flinders’ share common parents. The higher level of resistance in ‘Bersee’ was controlled by four genes. This conclusion was based on conventional genetic analysis, tests on F₂-derived F₇ single-seed descent lines and testcross progenies.     

α-生育酚转移蛋白研究进展

α-生育酚转移蛋白(α-TTP)由278个氨基酸构成,基因位于8q13染色体。α-TTP在多种组织上表达,但未发现其在血液组织上表达。氧浓度及血清α-生育酚浓度等因子调节α-TTP组织含量。就目前的报道可知,α-TTP主要有调节血浆α-生育酚的浓度、维持大脑组织α-生育酚水平所必需的因子、参与维持妊娠及胎儿的正常发育等3方面的作用。     

红外反射式播种机电子监测装置的设计

针对目前播种机电子监测装置普遍存在的安装不便、布线复杂、维护困难和实用性差等问题,设计开发了红外反射式播种机电子监测装置,较好地克服了上述缺点。该装置的探头采用了红外反射式的检测原理,以高速单片机为核心,能实现软件抗干扰及计数精度补偿,体积小巧,可单侧安装,适用于各种排种管。同时,采用无线数据传输方式及无极性二总线布线方式,极大地简化了布线工作,尤其适用于大型宽幅播种机的作业需求。该装置与2BJQ-9气吸式精密播种机配套的田间试验结果表明:故障检知准确率为100%,落种计数检测精度>93%,具备声光告警功能,人机界面友好,操作方便,为播种机电子监测装置的广泛应用提供了新思路。