Expression of phenylalanine ammonia-lyase cDNA from rice in E. coli BL21DE3

AIM: To study the expression and its kinetics of rice phenylalanine ammonia-lyase gene encoding into E. coli as the basis of treatment for phenylketouria. METHODS: The phenylalanine ammonia-lyase-1-cDNA(rPAL-1-cDNA) from rice was recombined into E. coli high expression vector pET-28c and transformed into E. coli host strain BL21DE3. Engineering bacteria was then inducted by isopropyl-β-D-thiogalactoside (IPTG) for 1, 3, 5, 7 hours, in order to obtain high level expression. RESULTS: After induction, the expression level of fusion protein was 21.40%, 30.60%, 35.40%, 35.43% respectively. The fusion protein exhibited a band of 78.6 kD on SDS-PAGE analysis, but was not found in controls.The target protein was mainly existed in the form of inclusion body. CONCLUSION:Rice PAL gene expressing E. coli was established by gentic engineering technique.     

Curcumin attenuates rat lung ischemia/reperfusion injury by interfering with autophagy

AIM To investigate the role of curcumin （CUR） in lung ischemia/reperfusion （I/R） injury （LIRI） and its relationship with autophagy. METHODS 40 SD rats were randomly divided into sham operation （sham） group, I/R group, solvent （DMSO） group, CUR group and CUR+rapamycin （CUR-Rap） group. The rats were intraperitoneally injected with normal saline, DMSO, CUR or CUR+Rap before operation. After the rat LIRI model was established, the lung tissues were taken to measure W/D, TLW, IAR, and the contents of SOD and MDA were also measured to indicate the oxidative stress level. Light and electron microscopes were used to observed the morphology and ultrastrucure of lung tissues. The expression levels of autophagy-related proteins were determined by Western blot to evaluate autophagy levels. RESULTS Compared with sham group, wet weight/dry weight （W/D）, total lung water （TLW）, injured alveoli rate（IAR） and malondialdehyde （MDA） content in all other groups were increased, superoxide dismutase （SOD） activity was decreased, the levels of autophagy were increased （P<0.05）, and lung tissue injury and cell ultrastructural damage were aggravated in CUR group. Compared with DMSO group, W/D, TLW and IAR and MDA content were decreased, SOD activity was decreased, autophagy levels were also decreased （P<0.05）, and lung tissue and cell ultrastructural damage were attenuated. Compared with CUR group, W/D, TLW, IAR and MDA content were increased, SOD activity declined, the autophagy levels were increased （P<0.05）, and damage of lung tissues and cells were more serious in CUR-Rap group. CONCLUSION Curcumin attenuates the lung I/R injury in rats, and its mechanism may be related to the reduction of oxidative stress and the inhibition of autophagy.     

论网络环境下的写作与道德

随着计算机网络的发展,写作环境发生了很大变化。论述了网络对写作带来好处的同时,也对写作道德产生冲击,出现一些不良现象。论文在此基础上提出了如何适应网络下的写作环境,提高写作道德的策略。。     

一起东佛里生奶绵羊附红细胞体病流行病学调查、诊疗报告

为探究附红细胞体在内蒙古呼和浩特市托克托县地区的流行情况,接诊呼和浩特托县地区某东佛里生奶绵羊养殖场病例,该场近一周多圈舍出现产奶羊只体温升高、精神沉郁、瘫软、食欲减退或废绝等症状,有出现症状1 ~ 2 d迅速死亡病例,也有使用抗生素硫酸庆大霉素-青霉素联用结合补液治疗1周无好转或死亡病例,死亡总数超8只,仍有10余只相似症状正在接受治疗。经现场剖检、圈舍环境调查、样品实验室检测,结合临床诊疗,确诊此次疫情为奶绵羊附红细胞体病,且周边羊养殖场（户）羊只也存在附红细胞体感染。说明附红细胞体在托克托县呈地方性流行。     

紫花苜蓿的饲用价值与生态价值

紫花苜蓿具有很高的饲用价值和多重生态功能,被誉为“牧草之王”,在世界上被广泛种植,在我国已有2000多年的栽培历史。但我国紫花苜蓿产业在育种、筛选适合品种和利用等方面与发达国家仍有很大差距。进一步认识紫花苜蓿潜在饲用和生态价值,在解决我国蛋白质资源的严重缺乏、     

甘蓝型冬油菜在西北寒旱区适应性分析

为了研究甘蓝型冬油菜在西北寒旱区的适应性,以29份甘蓝型冬油菜品系为材料,分析在天水、兰州两个试点越冬率、生育期、产量、含油量及农艺性状的差异。结果表明,参试品系在天水试点越冬率均高于兰州试点,在天水试点,21份参试品系越冬率80.00%以上,而兰州试点在覆盖条件下越冬率平均为14.49%,最高为平甘1号(48.50%)。联合方差表明,试点气候差异是引起越冬率差异的最主要原因。与天水试点相比,参试品系北移至兰州试点后越冬期延长,冬后生育期缩短,全生育期延长;在天水试点参试品系株高、分枝部位、主花序长度、千粒重、折合每667 m~2产量、含油量平均值分别为133.52 cm、32.79 cm、51.37 cm、3.15 g、184.20 kg、40.16%,较兰州分别高22.11 cm、31.58 cm、2.47 cm、0.66 g、160.54 kg、22.54%;变异分析表明,在天水试点参试品系越冬率、主要农艺性状、产量、含油量变异系数相对兰州试点较小,相对稳定。结论:天水试点气候条件更适合甘蓝型冬油菜的生长,参试品系越冬率高、农艺性状良好、产量高、含油量高,适应性强。     

昆虫病原线虫共生菌5-5B培养特性及杀虫活性研究

对一株昆虫病原线虫共生菌5-5B菌株的发酵条件进行的研究结果表明,最适温度为28℃,最适起始pH7.3～7.8,最佳振荡频率160r/min,250ml三角瓶内装液40ml,接菌量为4%。5-5B菌株发酵液对小菜蛾初孵幼虫的杀虫活性研究表明,250ml三角瓶内装液40ml时,校正死亡率为62.78%;接菌量4%时,校正死亡率63.84%;起始pH7.3时,校正死亡率65.49%。     

近45年内蒙古乌审旗气候变化对沙尘天气的影响

利用1961-2005年内蒙古乌审旗气象台站的地面观测资料,分析气候年代际变化特征,探讨气候变化对沙尘天气的可能影响。结果表明:近45年来,乌审旗年平均气温以0.48℃/10 a的趋势变暖,近5年气温比20世纪60年代升高了1.8℃,1961-1996年为偏冷时段,1996-2005年为偏暖时段。降水量以15.15 mm/10 a的趋势减少,20世纪60年代至21世纪经历了一个"少、多、少、多"的年代际变化过程。降水量变化分4个多雨时段和4个少雨时段。年大风日数以3.53 d/10 a的趋势减少,20世纪60年代是大风天气的频发期,近5年大风日数较60年代减少了197 d。年沙尘天气日数以14.96 d/10 a的趋势减少,20世纪60-70年代是沙尘天气的频发期,近5年较20世纪60-70年代减少了624.5 d;从季节变化来看,沙尘天气多的季节大风也多,气温回升快,降水量偏少;不同年代气候要素的不同组合对沙尘天气的影响有所差异,春季沙尘日数与同期大风日数的正相关较显著,与同期的气温和前一年夏季降水也显现出较好的负相关关系,夏季降水对第2年沙尘天气的预报有一定参考意义。     

南京市小麦田杂草调查及其防除对策

通过对南京市各县区麦田杂草的系统调查,探讨本地小麦田杂草群落结构及发生规律,调查发现目前南京市小麦田间常见杂草有11科26种,主要杂草有猪殃殃、播娘蒿、看麦娘、荠菜、大巢菜、牛繁缕、婆婆纳、麦家公、野燕麦、泽漆等。并对已有小麦田杂草农业防除配套技术进行了充实和完善。     

鸡公山国家级自然保护区散孔材、环孔材树种木质部结构和功能的关系

【目的】木质部解剖结构是植物水力功能和水分利用策略的基础。散孔材和环孔材的导管分布和形态存在显著差异,对2种材性树种木质部解剖结构和水力功能的关系进行比较,有助于理解不同材性树种的水分适应机制。【方法】选取河南省信阳市鸡公山自然保护区中的3个散孔材树种(枫香Liquidambar formosana、旱柳Salix matsudana、深山含笑Michelia maudiae)和3个环孔材树种(槲树Quercus dentata、楝Melia azedarach、野核桃Juglans cathayensis),研究2种材性树种的枝水力功能(比导率和栓塞抗性)和解剖结构的关系。【结果】3个环孔材树种比导率更大,3个散孔材树种栓塞抗性更强;在物种水平上,只有散孔材树种深山含笑比导率和栓塞抗性呈显著负相关(P<0.05),存在水力效率-安全权衡。3种散孔材树种相较于3种环孔材树种具有更大的导管密度、导管壁厚度跨度比和更小的导管直径、导管壁厚度。【结论】环孔材树种倾向于通过增大导管直径显著提高其输水效率,从而避免水势下降、降低潜在栓塞风险。散孔材树种木质部结构中的导管壁厚度和导管壁厚度跨...