浙北稻麦连作区稻田糠稷发生对水稻生长的影响及对除草剂敏感性研究

调研了浙北稻麦连作区稻田糠稷发生及分布状况,并考察了糠稷种子萌发特性和对水稻生长的影响及植株对不同除草剂的敏感性,旨在为有效防治糠稷提供参考.结果 表明,糠稷在浙北稻麦连作区直播田发生的相对优势度在0～2.8％、机插田发生的相对优势度在0～3.6％;糠稷种子在光照条件下才能萌发,光照36℃(12 h)/黑暗28℃(12...     

猪δ冠状病毒实时荧光RT-PCR检测方法的建立与应用

为灵敏、快速检测猪δ冠状病毒(porcine deltacoronavirus,PDCoV),根据PDCoVM基因保守区域设计引物和探针,建立了一种PDCoV实时荧光RT-PCR检测方法,并评价了该方法的特异性、灵敏性和重复性。结果显示,该方法的拷贝数对数值与Ct值在1.3×10³～1.3×10⁷ copies/μL拷贝数浓度范围内呈现良好的线性关系,R²=0.994;最低检出限为13 copies/μL,且无非特异性扩增;批内和批间重复性试验变异系数(CV)为0.24%～2.15%,均小于3%。利用该方法和普通RT-PCR对42份临床样品同时进行检测,发现本方法比普通RT-PCR灵敏性更高,二者符合率为95.2%。以上结果表明,本试验建立的实时荧光RT-PCR方法灵敏、特异、可靠,可用于PDCoV的临床检测和流行病学调查。     

大豆主要过敏原Gly m Bd30K蛋白单克隆抗体的制备与应用

利用大豆主要过敏原Gly m Bd 30K蛋白抗原表位蛋白为免疫原免疫BALB/c小鼠,取免疫小鼠脾细胞与小鼠骨髓瘤NS-1细胞融合.采用半固体培养基法和有限稀释法相结合的方法快速筛选获得稳定分泌的特异性杂交瘤细胞,用杂交瘤细胞株诱生小鼠腹水,应用蛋白A亲和层析法进行抗体纯化.采用Ig类与亚类鉴定试剂盒鉴定该单克隆抗体...     

The effect of bentonite concentration on the drug delivery efficacy of a pH-sensitive alginate/bentonite hydrogel

We produced a protein loaded, pH-sensitive alginate-bentonite hydrogel for wound dressings. Alginate is a nontoxic polysaccharide with favorable pH-sensitive properties that make it useful for the intestinal delivery of protein drugs. However, the use of alginate for drug delivery is limited by drug leaching and rapid dissolution of alginate at the higher pH, which may result in lower entrapment efficiency and a burst in the release of entrapped protein drugs. To overcome these problems, we created a novel cross-linked alginate-bentonite hydrogel by combining mineral-rich bentonite with the alginate matrix along with an additive to ensure controlled release. We analyzed the gel in the drug loading process in an aqueous environment by looking at the release profiles of a model protein drug (BSA) from the hydrogel at pH values of 4.5, 5.2 (skin area) and 7.4, 9.2 (wound area). The swelling ratio decreased with bentonite concentration, but did not fall below 6. The rate of drug release was slowest at a pH value of 4.5 and fastest at a pH value of 9.2. The rate of drug release decreased with bentonite concentration. The presence of bentonite prevents the rapid dissolution of alginate at the higher pH, ensuring the controlled release of the entrapped drug.     

悼念绿色革命之父布劳格博士

布劳格博士从事国际农业研究65年,主要贡献包括:(1)培育的矮秆高产小麦品种为解决世界粮食问题做出了杰出贡献,被誉为绿色革命之父,他不仅是CIMMYT的创始人,也是整个国际农业研究磋商组织的创始者;(2)创立了世界粮食奖;(3)开展了以推广玉米新品种为主要内容的非洲农业革命.     

Hydroxycinnamoylmalic acids and their methyl esters from pear (Pyrus pyrifolia Nakai) fruit peel

Two novel caffeoylmalic acid methyl esters, 2-O-(trans-caffeoyl)malic acid 1-methyl ester (6) and 2-O-(trans-caffeoyl)malic acid 4-methyl ester (7), were isolated from pear (Pyrus pyrifolia Nakai cv. Chuhwangbae) fruit peels. In addition, 5 known hydroxycinnamoylmalic acids and their methyl esters were identified: 2-O-(trans-coumaroyl)malic acid (1), 2-O-(cis-coumaroyl)malic acid (2), 2-O-(cis-coumaroyl)malic acid 1-methyl ester (3), 2-O-(trans-coumaroyl)malic acid 1-methyl ester (4), and 2-O-(trans-caffeoyl)malic acid (phaselic acid, 5). The chemical structures of these compounds were determined by spectroscopic data from ESI MS and NMR. Of all the isolated compounds, five hydroxycinnamoylmalic acids and their methyl esters (2-4, 6, 7) were identified in the pear for the first time.     

滨岸排污口对潮滩沉积物中重金属的影响研究

通过对排污口附近及对照点的潮滩沉积物中重金属Zn ,Cu ,Cr和Pb的含量分析发现:各采样点沉积物中的重金属含量均高于环境背景值,平均含量约为环境背景值的2～3倍,排污口附近潮滩沉积物中重金属的含量明显高于对照点潮滩沉积物中的含量;各采样点的柱状沉积物中重金属的含量随深度的变化呈现出一定的变化规律;在垃圾填埋场附近高中低潮滩由于距离排污口的远近不同,表层沉积物中重金属的含量依次降低;对各采样点沉积物中重金属含量的相关性分析发现各点沉积物中累积的重金属的来源有所不同:在排污口附近潮滩的沉积物中重金属主要来源于排污口排放的污水,而对照点朝阳农场潮滩沉积物中重金属主要来源于自然的本底输入或海水外源输入     

上海市区公园表层土壤铅含量及其污染评价

通过对上海市区44个公园土壤中Pb含量的调查,发现表层土壤中Pb的平均含量为55．06 mg/kg, 变幅为26．39-174．35 mg/kg,为上海市土壤环境背景值的1．04-6．85倍。运用地积累指数法对公园表层土壤Pb 污染进行评价,结果表明:超过半数的公园为轻度污染至中等污染,近1/3的公园无污染, 6个公园达到中等污染和中等污染至强污染水平。通过对土壤Pb含量的空间分布分析发现,上海市区公园土壤中Pb主要来源于交通和工业污染,土壤Pb含量与公园建成时间无显著性相关。     

燕麦混粉馒头加工品质特性评价

在传统的馒头加工过程中,添加一定比例的燕麦粉,研究其对馒头感官品质和质构的影响。结果表明,在小麦粉中添加适量的燕麦粉,加工出的馒头在结构、色泽、韧性等感官特性方面都有改善,馒头的硬度、咀嚼性、黏聚性等物性参数得到改变。当燕麦粉添加量为25%时,不仅馒头感官评价得分最高,而且营养价值也得到极大提高。因此,建议在馒头加工中添加25%的燕麦粉为宜。     

Variation and correlation analysis of flavonoids and carotenoids in Korean pigmented rice (Oryza sativa L.) cultivars

Flavonoids and carotenoids of pigmented rice ( Oryza sativa L.), including five black cultivars and two red cultivars, from Korea were characterized to determine the diversity among the phytochemicals and to analyze the relationships among their contents. Black cultivars were higher in flavonoids and carotenoids than the red and white cultivars. The profiles of eight phytochemicals identified from the rice grains were subjected to principal component analysis (PCA) to evaluate the differences among cultivars. PCA could fully distinguish between these cultivars. The Heugjinjubyeo (BR-1) and Heugseolbyeo (BR-2) cultivars were separated from the others based on flavonoid and carotenoid concentrations. Flavonoid contents had a positive correlation with carotenoid contents among all rice grains. The BR-1 and BR-2 cultivars appear to be good candidates for future breeding programs because they have simultaneously high flavonoid and carotenoid contents.