不同规格野生黄鳍金枪鱼肌肉营养分析与评价

探究不同规格黄鳍金枪鱼(Thunnus albacares)肌肉营养成分及品质差异,实验以野捕的 3种规格黄鳍金枪鱼J1 (4.2±1.2) kg、J2 (22.5±2.5) kg和J3 (50.8±3.9) kg为研究对象,通过常规生化分析方法对金枪鱼肌肉的常规营养成分、氨基酸、脂肪酸及矿物质元素进行比较分析。结果显示,(1) J1组水分含量显著高于J2、J3组;J2、J3组粗蛋白含量显著高于J1组(P<0.05);J3组粗脂肪含量显著高于J1、J2组(P<0.05)。(2)检出19种常见氨基酸,氨基酸含量最高的为谷氨酸(3.04~ 3.25 g/100 g),必需氨基酸中含量最高的为赖氨酸(2.02~2.15 g/100 g),最低的为色氨酸(0.31~ 0.45 g/100 g)。非必需氨基酸含量J3>J2>J1 (P<0.05);必需氨基酸、呈味氨基酸含量J1组显著低于J3组(P<0.05)。依据氨基酸评分(AAS),缬氨酸为第一限制性氨基酸;以化学评分(CS)为评分标准,J1、J2组第一限制性氨基酸为色氨酸,J3组为苯丙氨酸+酪氨酸。(3)各组共检出25种脂肪酸,以多不饱和脂肪酸(PUFA)为主,含量最高的为二十二碳六烯酸(DHA),占总脂肪酸含量的37.46%~39.18%。DHA含量J3组显著高于J1、J2组;二十碳五烯酸(EPA)含量J2、J3组显著高于J1组;DHA∶EPA比值J1组显著高于J2、J3组(P<0.05)。单不饱和脂肪酸(MUFA)含量J3>J2>J1;PUFA含量J3组显著高于J1、J2组(P<0.05)。PUFA/饱和脂肪酸(SFA)、n-3系多不饱和脂肪酸/n-6系多不饱和脂肪酸(n-3/n-6)比值J2、J3组显著高于J1组(P<0.05)。h/H比值J3组显著高于J1、J2组(P<0.05)。(4) J2、J3组Na、Ca含量显著高于J1组,J1组K含量最高且显著高于J2、J3组(P<0.05)。4种重金属元素均低于食品中建议的最大允许限量,其中Fe含量最大的为J3组,且J3>J2>J1 (P<0.05);Cu含量最大的为J3组,且显著高于J1组(P<0.05)。综合分析,大规格黄鳍金枪鱼具有更好的营养质量,本研究为居民膳食的选择及黄鳍金枪鱼人工配合饲料的配制提供了科学依据。     

国内外农业信息化建设对佳木斯地区的启示

分析借鉴国内外农业信息化建设的经验,对加快实现佳木斯地区农业的信息化具有重要意义.为此,当前世界上农业信息化建设工作比较发达的欧美国家信息化建设的工作经验;分析了开展此项工作相对较晚的亚洲国家农业信息化建设的情况以及我国近年来农业信息化工作的情况.由此得出国内外经验给佳木斯地区开展农业信息化建设工作的4点启示:一是发挥政府的宏观调控职能是开展好农业信息化建设的保障;二是健全基础设施是开展好农业信息化建设的前提;三是搞好信息数据库建设是开展好农业信息化建设的基础;四是做好科研、教育和推广的有机结合是开展好农业信息化建设的必然.     

果蔬汁加工技术进展

我国是水果和蔬菜生产大国,产量均居世界第一位。发展果蔬汁产业可以提高果蔬的附加值,具有明显的经济和社会效益。近年来,我国果蔬汁的加工技术取得了一定的进步。介绍了近年果蔬汁饮料加工领域的新技术,以及果蔬加工的发展方向。     

孕穗期低温条件下ABA对水稻结实率及叶片生理特性的影响

为了明确ABA对孕穗期低温下水稻结实率及叶片生理特性的调控效应,本试验在盆栽条件下,以2个水稻(Oryza sativa L.)品种‘龙粳11’（冷敏型）和‘龙稻5’（耐冷型）为材料,于孕穗期在人工气候室进行低温（15℃,持续1,2,3,4,5天）处理,并喷施不同浓度的脱落酸(ABA),研究低温条件下ABA对不同水稻结实率的调控效应,同时探讨了ABA和低温对水稻叶片膜透性、抗氧化酶等生理特性的影响。结果表明：低温条件下,‘龙稻5’的结实率变化不大,‘龙粳11’的结实率显著降低,20 mg/L的ABA能够有效缓解低温伤害,相对提高低温胁迫下水稻的结实率。叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性表现出先升高后下降的变化趋势,‘龙稻5’的抗氧化酶活性、可溶性糖和可溶性蛋白含量高于‘龙粳11’,但丙二醛(MDA)含量和相对电导率低于‘龙粳11’。ABA可提高冷敏品种的抗氧化酶活性、可溶性糖和可溶性蛋白的含量,同时可降低MDA含量和相对电导率。这说明ABA可以通过调控水稻抗氧化酶、可溶性糖等生理指标的活性及含量,进而提高冷敏水稻品种的耐冷性。     

Lignin characteristics of bast fiber and core in kenaf, bark and wood of paper mulberry and mulberry

The structural features of bast fiber and core lignins in kenaf (Hibiscus cannabinus), bark and wood lignin of paper mulberry (Broussonetia papyrifera (L.) Vent × Broussonetia kazinoki Sieb.) and mulberry (Morus bombycis) were characterized by alkaline nitrobenzene oxidation, ozonation and methoxyl group determination. Bj?rkman lignins were isolated from bast fiber and core, and bark and wood fractions of the plant samples, and structural characteristics were investigated by ¹H NMR and ¹³C NMR spectroscopies. Kenaf bast fiber gave very high molar ratio of syringaldehyde to vanillin (S/V) of alkaline nitrobenzene oxidation products, while methoxyl content was about the same as that of the core fraction. Results of ¹H NMR and ¹³C NMR of Bj?rkman lignin suggested the presence of aliphatic fragments in lignins isolated from paper mulberry and mulberry bark, but not in kenaf bast fiber. The lower yield of alkaline nitrobenzene oxidation products from bast fiber and bark might be due to the higher content of condensed structure of lignin compared to core fraction. Total yield of erythronic (E) and threonic (T) acids of ozonation products and the molar ratio of erythronic acid to threonic acid (E/T) of the bast fibers and bark were lower than the corresponding core and wood fractions, suggesting that the contents of arylglycerol-β-aryl ether intermonomer linkages in the bast fiber and bark lignin were lower than those of the core and wood fractions. Methoxyl content of bark lignin was lower than the corresponding wood lignin. The methoxyl content of the extract-free kenaf bast fiber was similar to that of the core fraction, while the values of paper mulberry and mulberry bark were about one-half of the corresponding wood fractions, respectively. In bark lignins, the methoxyl contents of Klason lignin and Bj?rkman lignin from bark were lower than those of the extract-free barks. This result suggests that the purity of Klason lignin and Bj?rkman lignins of bark may be rather low.     

新疆边境跨界动物疫病传入风险因素调查

新疆地域辽阔,周边国家动物疫情形势复杂,随时有传入外来动物疫病的危险。调查结果表明新疆接壤国家多且边境线长,地理环境复杂,动物及动物产品贸易频繁,野生动物种类繁多,虽然边界线隔离设施较好,但仍然存在跨界动物疫病传入的风险因素,需要有针对性地强化边境防控措施。     

Multiple amino acid substitutions are involved in the adaptation of H9N2 avian influenza virus to mice

To explore adaptation of avian influenza virus to mice we previously performed serial lung-to-lung passages of the influenza A/Chicken/Jiangsu/7/2002 (H9N2) strain, resulting in the isolation of a variant influenza strain lethal for mice. We now report that virulence correlates with improved growth characteristics on mammalian cells and extended tissue tropism in vivo. Sequencing of the complete genomes of the wild-type and mouse-adapted viruses revealed 25 amino acid substitutions. Some were found to reiterate known substitutions in human and swine H9N2 influenza isolates. Functions affected include nuclear localization signals and sites of protein and RNA interaction, while others are known determinants of pathogenicity and host specificity such as the viral polymerase PB2 E627K substitution. These observations suggest that enhanced growth characteristics and modified cell tropism may contribute to increased virulence in mice. We conclude that multiple amino acid substitutions are likely to be involved in the adaptation of H9N2 avian influenza virus to mice.     

番鸭小鹅瘟病胶乳凝集试验与病毒分离的比较研究

应用GPV胶乳凝集方法（LPA）和病毒分离（VI）检测人工感染病例9份、健康对照6份,临床疑似送检病鸭28份。其中人工感染样品检测LPA和VI符合率为93.3%（14/15）;临床疑似样品检测LPA和VI符合率为89.3%（25/28）;两者总符合率达90.7%（39/43）。LPA方法具有简便（肉眼可判定,不需仪器）、快速（检测抗原20min内）、特异、准确等优点,比VI更适合临床使用。     

乳牛血清钙磷乘积与骨密度的关系

对３０头乳牛的血清钙，血清无机磷和骨密度值进行了测定，并进行了钙磷乘积与骨密度值的相关分析，研究表明，血清钙磷乘积为３２（２８～３４）时，骨密度增加最少，其增加值与血清钙，钙磷比值呈显著负相关，钙磷乘积为３８（３５～４０）时，骨密度增加最多，其增加值与血清钙，钙磷化呈极显著负相关，与血清无机磷呈显著性相关，钙磷乘积为５５（４１～１０４）时，骨密度增加居第二位，其增加值与血清钙，血清无机磷，钙磷乘积     

里氏木霉重组t-PA纯度、分子量及等电点鉴定

基因工程菌株里氏木霉(Trichodermareesei)生物合成的组织型纤溶酶原激活剂(tissue-typeplasminogenactivator,t-PA)经分离纯化后,采用还原SDS-PAGE和非还原PAGE分析达到了电泳纯,采用Superdex75PrepGrade凝胶过滤色谱分析达到了色谱纯;采用还原SDS-PAGE分析其相对分子质量为6.6×104,SDS-聚丙烯酰胺凝胶电泳纤维蛋白自显影法检测其相对分子质量为6.6×104,与相关文献报道的一致。等电聚焦电泳测定其等电点为4.24。