牛肠激酶催化亚基工程菌培养条件的探索与鉴定

目的：探索牛肠激酶催化亚基工程菌高效表达的培养条件。方法：牛肠激酶催化亚基基因的初步表达,筛选构建工程菌,从以下方面入手优化培养条件：培养基的组成、摇瓶发酵培养条件、培养基的PH、种龄、接种量、培养时间等,并且通过Western Blotting和SDS-PAGE等鉴定不同条件下的实验结果,从而确定最佳培养条件。结果：通过鉴定实验结果,从不同种平行培养条件中选择产量最高的培养条件,作为最优培养条件。结论：成功地探索并鉴定了工程菌的适宜培养条件。     

553例女性宫颈高危型HPV感染与宫颈病变的相关性研究

目的：研究女性生殖道高危型人乳头瘤病毒（high risk human papilloma virus,hrHPV）感染现状及子宫颈上皮内瘤样病变（cervical intraepithelial neoplasia,CI N）的现患率,并分析该人群年龄与HPV感染及宫颈癌前病变的相关性以及hrHPV病毒载量与宫颈病变之间剂量-效应关系。方法：对553例30岁-78岁有性生活史的女性进行以人群为基础的横断面调查。对所有接受筛查的妇女均行宫颈HPV检测及电子阴道镜下病理活检,并以病理结果作为诊断子宫颈病变的金标准。资料采用EXCEL整理,利用x2检验和非条件Logistic回归分析危险因素和CI N的关系。结果：553例受检对象总体阳性检出率为18.0%。hrHPV感染情况在不同年龄段分布有显著差异,hrHPV病毒载量越高宫颈病变的程度越重。结论：不同年龄段hrHPV感染情况不同,hrHPV病毒载量与宫颈病变之间存在剂量-效应关系。     

强化乙酰辅酶A供应对裂殖壶菌合成二十二碳六烯酸的影响

细胞液中乙酰辅酶A的持续供应是脂肪酸高效积累的必要条件。考虑到甲羟戊酸和脂肪酸合成途径共用相同的前体乙酰辅酶A,抑制甲羟戊酸途径可能促使更多的乙酰辅酶A流向脂肪酸合成。通过添加前体物质或/和甲羟戊酸途径酶的抑制剂以强化乙酰辅酶A的供应,即在裂殖壶菌发酵起始或/和后期添加乙酸、发酵起始添加甲羟戊酸途径酶的抑制剂辛伐他汀或柠檬酸、发酵起始同时添加乙酸和辛伐他汀或柠檬酸并考察其对裂殖壶菌合成二十二碳六烯酸 (DHA)的影响,结果发现发酵起始同时添加6mmol/L的乙酸和1μmol/L的辛伐他汀时,DHA产量最高,达到13.21g/L,比对照提高了46.61%。     

利用高通量测序快速检测疑似感染患者体内未知病原体

采用第二代高通量测序技术从复杂的疑似感染患者组织标本中直接快速检测未知病原体.方法:取临床和实验室均不能确诊的病人血液和淋巴组织,进行病毒DNA和RNA的提取,直接用于第二代高通量测序,将测序结果用于生物信息学分析,与本地化的病毒核酸数据库进行比对,寻找潜在的病毒序列.结果:生物信息学分析显示,3901条序列reads与人内源性病毒K113同源;当使用K113特异性引物对经过Dnasel处理的患者和正常个体进行荧光定量RT - PCR时,发现在患者体内K113病毒基因的表达远远高于正常个体,提示该患者可能存在K113病毒的感染.结论:第二代高通量测序可能用于快速检测未知病原体.     

弱光胁迫对大田长春花生物量分配及次生代谢的影响

以长春花（Catharanthus roseus(L.) Don.）为材料,研究了田间栽培长春花在全光和20%透光率下,经过一个生长季后生物量配置、抗氧化次生代谢产物和文朵灵、长春质碱、长春碱等目的活性物质含量的变化。研究结果表明,弱光条件显著抑制了长春花植株总生物量增长,特别是抑制了有性生殖的投入;弱光组叶片总酚和总黄酮含量显著降低,干重含量分别为对照组的62.50%和50.00%,原花青素含量则略有升高,但与全光组的差异不显著;弱光组叶片文朵灵和长春质碱含量显著高于对照组,长春碱含量略有上升但差异不显著,受生物量降低影响,3种生物碱的产量均显著下降。上述结果表明,长春花能够调控生理代谢以适应低光强环境,特别是文朵灵和长春质碱含量提升显著,林下低光强环境种植长春花可以满足土地资源充分利用和文朵灵、长春质碱优质原料的需求。     

鹤庆深钻孢粉记录揭示的气候变化与西南季风演化

本文在鹤庆深钻孢粉分析的基础上,把各孢粉类型划分成不同的孢粉生态组,结合孢粉多样性指数,系统重建云南鹤庆地区2.78 Ma以来的占气候演化所经历的8个大的阶段,与西南季风在滇西北地区8次大的变化相对应:即在2.729-2.608Ma和0.118Ma-11.83ka BP期间,气候整体湿润,冬、夏季降水的季节性较强,反映西南季风相对较强盛;1.447-0.342Ma期间,气候整体逐渐变湿,冷暖、干湿变化幅度逐渐变大,气候组合特征逐渐变复杂,反映西南季风逐渐增强,其波动幅度也逐渐变大,并于0.991-0.342Ma期间达到最强盛,其波动幅度也最大;而在2.780-2.729Ma、2.608-1.447Ma和0.342-0.118Ma期间,气候普遍相对温暖干旱,西南季风相对较弱.     

Skeletal morphology and the phylogeny of skuas (Aves: Charadriiformes,Stercorariidae)

The skuas (Aves: Charadriiformes, Stercorariidae) consist of two assemblages. On the basis of size, plumage, and distributional similarities, each of the two assemblages has long been considered monophyletic, and this traditional hypothesis has commonly been manifested in the recognition of two genera, Stercorarius and Catharacta; conversely, more recently collected molecular and ectoparasite evidence yields an alternative hypothesis, in which one member of Stercorarius, Stercorarius pomarinus, is more closely related to the forms in Catharacta than to the other Stercorarius sp. In this study we used skeletal morphology to test the competing hypotheses of skua phylogeny. Cladistic analysis of 141 osteological characters provided strong support for the molecular/ectoparasite hypothesis. However, those skeletal data did not support a sister‐taxon relationship between S. pomarinus and Catharacta skua, as inferred from mitochondrial DNA sequence data; instead, they resolved pomarinus as the sister of a monophyletic Catharacta. Additionally, our skeletal evidence did not support a sister‐group relationship between skuas and auks, as constraining skua/auk monophyly increased the tree length by nearly 5%. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 157 , 612–621.     

The Effect of Lactobacillus plantarum BW2013 on The Gut Microbiota in Mice Analyzed by 16S rRNA Amplicon Sequencing

Lactobacillus plantarum BW2013 was isolated from the fermented Chinese cabbage. This study aimed to test the effect of this strain on the gut microbiota in BALB/c mice by 16S rRNA amplicon sequencing. The mice were randomly allocated to the control group and three treatment groups of L. plantarum BW2013 (a low-dose group of 10⁸ CFU/ml, a medium-dose group of 10⁹ CFU/ml, and a high-dose group of 10¹⁰ CFU/ml). The weight of mice was recorded once a week, and the fecal samples were collected for 16S rRNA amplicon sequencing after 28 days of continuous treatment. Compared with the control group, the body weight gain in the treatment groups was not significant. The 16S rRNA amplicon sequencing analysis showed that both the Chao1 and ACE indexes increased slightly in the medium-dose group compared to the control group, but the difference was not significant. Based on PCoA results, there was no significant difference in β diversity between the treatment groups. Compared to the control group, the abundance of Bacteroidetes increased in the low-dose group. The abundance of Firmicutes increased in the medium-dose group. At the genus level, the abundance of Alloprevotella increased in the low-dose group compared to the control group. The increased abundance of Ruminococcaceae and decreased abundance of Candidatus_Saccharimonas was observed in the medium-dose group. Additionally, the abundance of Bacteroides increased, and Alistipes and Candidatus_Saccharimonas decreased in the high-dose group. These results indicated that L. plantarum BW2013 could ameliorate gut microbiota composition, but its effects vary with the dose.     

环境因子对养殖条件下出蛰的东北林蛙存活和生长的影响

实验通过在设施环境下和控制条件下,研究出蛰温度、湿度及风速3种环境因素对林蛙生长和存活的影响,目的在于探索东北林蛙(Rana dybowskii)适宜的出蛰环境。结果表明:温度是影响东北林蛙出蛰存活和生长的重要因素,当出蛰温度低于16℃,东北林蛙有较高的成活率,而出蛰温度高于20℃,则会引起70%以上的东北林蛙死亡,出蛰期间温度缓慢提高有利于东北林蛙生长和存活。东北林蛙出蛰期间适宜的湿度在80%以上,湿度低于60%则对东北林蛙不利。出蛰环境以无风为好,有风会造成东北林蛙的死亡。在人工养殖过程中,可依据当地、当年的气候来进行出蛰。出蛰当日平均温度宜在15℃以下。     

茉莉酸甲酯和苯丙氨酸对辣椒果实品质的影响

本文研究了不同浓度的茉莉酸甲酯（MeJA）和苯丙氨酸（Phe）对‘湘研5号’辣椒果实不同发育时期的辣椒素、二氢辣椒素、维生素c以及干物质含量变化的影响。结果表明：500和1000mg·L-1 MeJA处理60d后的辣椒素含量分别比对照提高了41．7％和58．4％：同时500mg.L-1 MeJA处理能促进辣椒果实中的二氢辣椒素、维生素C的积累,对干物质积累也有一定作用。60mg·L-1 Phe处理能提高辣椒果实中辣椒素、二氢辣椒素和干物质的含量,但对维生素C影响不显著。