Effects of NaCl and Ca^2＋ on Membrane Potential of Epidermal Cells of Maize Roots

The effects of salt-stress on plants involve not only the water stress caused by low osmotic pressure, but also the toxicity of excess Na^＋. A large amount of Na^＋ entering cells would reduce K^＋ uptake, which leads to an imbalance of K：Na ratio in cells. One of the reasons for the reduced K^＋-uptake is the closure of K^＋-channel which is controlled by membrane potential. Calcium is usually applied to improve the growth of plants on saline soils and shows positive influence in the integrality of cell membrane. This study applied glass microelectrode technique to monitoring the NaCl-induced changes of membrane potential of root epidermal cells of maize （Zea mays L., Denghai 11） seedlings at NaCl concentrations of 0, 8, 20, 50, 100, 200 mmol L^-1, respectively. The effect of Ca^2＋ on the changes of membrane potential caused by NaCl was also studied. The results showed that： NaCl caused cell membrane depolarization. The depolarization became greater and faster with increasing of NaCl concentration. Moreover, the extent of depolarization was positively correlated with NaCl concentration. The addition of calcium postponed the depolarization, and decreased the degree of depolarization caused by NaCl. High NaCl concentration leads to depolarization of maize root cell membrane, which can partly be counteracted by calcium.     

Effects of Monoclonal Antibody Against Adipocyte-Specific Membrane Protein on Lipid Metabolism in Pigs

This study was to investigate the regulation of monoclonal antibodies against adipocyte membrane proteins （McAb） on lipid metabolism in pigs. Forty Landrace x Saba pigs were randomly divided into eight groups; the control group was given 10 mL saline and the treat groups were given monoclonal antibody against adipocyte-specific membrane protein with 0.1, 0.5, and 1.0 mg kg-I body weight at 15 and 60 kg body weight, respectively, by intraperitoneal injection. The results showed that McAb could increase, significantly, serum lipoprotein lipase activity and reduce serum nonesterified fatty acid （NEFA） content. Meanwhile, McAb increased content of serum lipid, triglyceride （TG）, cholesterol （CHO）, high density lipoprotein （HDL）, and low density lipoprotein （LDL） both at 15 and 60 kg body weight. However, McAb affected more significantly the lipid metabolism at 15 kg body weight than at 60 kg body weight. Moreover, this effect of McAb on lipid metabolism exhibited dose-dependent effect. These results suggested that this monoclonal antibody increased lipase activity, promoted lipolysis, and utilization of lipid so that McAb could be applied to restrain excessive fat deposition in porcine production through the regulation of fat metabolism.     

Expression of Aminopeptidase N1 （APN1）, the Main Receptor Protein for Bacillus thuringiensis CrylA Toxin from Helicoverpa armigera Larval Midgut in Trichoplusia ni cells

The aim of this article is to successfully express the Bt （Bacillus thuringiensis） toxin receptor protein located on the internal membrane of larval midgut of cotton bollworm （Helicoverpa armigera Hübner） within eukaryotic expression system, which is one of the key links for clarifying the relationship between receptor and Bt resistance. The fragments of aminopeptidase N1 （APN1） gene without signal peptide in the susceptible and the resistant H. armigera were cloned separately using PCR method, and were separately cloned into pUC 19 vector. After sequencing the gene, the fragments encoding for APN1 without signal peptide were cloned into the Bac-to-Bac baculovirus expression system with transfer vector pFastBacHTB under the polyhedron gene promoter. The recombinant transposing plasmid pFastBacHTB/APN1 was screened and then transformed into Escherichia coli DH10Bac. It was cultured in LB medium, which contained Te, Kan, Ge, X-gal, and IPTG. The resulting recombinant bacmid was transfected into cells of the insect Trichoplusia ni and recombinant baculoviruse was obtained. The lysate of cells infected with recombinant baculoviruse was analyzed by SDS-PAGE and blot analysis. The results showed that the recombinant baculoviruse was fully capable of expressing APN1. The APN1 gene successfully expressed in T. ni cell established the base for continuing the research on its function and relationshio of resistance with Bt.     

中华仙影海葵(Cereus sinensis Verrill)的人工繁殖试验(上)

中华仙影海葵(Cereus sinensis Verill)隶属于腔肠动物门、珊瑚虫纲、六放珊瑚亚纲、海葵目、绿海葵科、仙影海葵属,是一种辐射对称的二胚层海洋无脊椎生物,基部固着于泥砂中生活,柱体长筒状,体内有隔膜系,口盘宽阔,其上生有触手,以捕捉小型鱼、虾及贝类为食。江浙沿海将其奉为上等佳肴,口感独特,味道鲜美,是一种高档     

不同产地核桃隔膜、种皮及壳中黄酮含量的比较

采用超声提取法提取不同产地核桃不同部位总黄酮,以木犀草苷为对照品,采用HPLC法和比色法测定提取物中木犀草苷和总黄酮含量,比较不同产地核桃隔膜、种皮及壳中木犀草苷及总黄酮的含量差异,为药用核桃的道地性及药用部位提供依据。结果表明:不同产地核桃中木犀草苷含量为长治和田阿克苏塔里木大理秦岭,总黄酮含量为大理秦岭和田塔里木长治阿克苏。核桃不同组织部位中木犀草苷的分布为种皮壳隔膜,不同组织部位中总黄酮的分布为壳种皮隔膜。表明,不同产地核桃的黄酮成分含量有差别,山西核桃木犀草苷含量最高,但总黄酮含量最低;云南核桃总黄酮含量最高,但木犀草苷含量很低。核桃种皮中木犀草苷及总黄酮含量要高于隔膜中的,核桃种皮可能和隔膜有相似的药理活性,同样具有很好的药用价值。     

十字花科果实中假隔膜的比较解剖研究

首次对十字花科9族24属植物果实中假隔膜进行了比较解剖，结果表明：该科根据假隔膜可分为：①有或无假隔膜类型；②假隔膜薄、结构简单、细胞数量少和假隔膜厚、细胞数量多等类型；③两侧压扁与背腹压扁类型。确认了假隔膜的结构与分类的关联不大，而与角果开裂方式有密切的关系。     

气泵增氧在循环水工厂化养殖中的应用

利用气泵将空气中的氧与池水充分混合,养殖池与水处理池通过微孔曝气管道提高溶氧量。结果表明:一台8.5kw的气泵可以保障7个养殖池(1540 m3水体、52.5 t鲟鱼)溶解氧稳定在5.7mg/L以上,单个养殖池每小时耗电量为1.21kw,每吨鱼平均每天耗电成本为3.80元。     

苎麻韧皮纤维细胞超微结构研究

对苎麻韧皮纤维细胞的超微结构进行了电子显微观察。结果表明，苎麻韧皮纤维为具隔的单细胞纤维，纤维细胞的不同部位存在着许多的外突型、内陷型和平滑型结节，节间长度为240—710μm，胞腔内存在大量的膜状横隔，膜间距离为60—90μm，纤维结节与胞腔隔膜没有一一对应的关系。巨原纤呈圆柱形，由圆筒形外壳和螺旋状的原纤构成，表现平滑，直径为0．25μm左右，普遍存在着交织现象，大多数趋向纤维轴向排列，在胞壁的不同部位，存在局部且整齐的间断现象。     

用于水稻机械插秧的小棚隔膜育苗技术的研究

用于水稻机械插秧的小棚隔膜育苗技术的研究韩伟，韩玉福，阎鹏（黑龙江省鸡西市农机推广站）（哈尔滨农业机械厂）１问题的提出插秧技术作为北方高寒地区解决水稻生育期短、提高其产量的重要措施被广泛推广应用之后，工厂化育秧、机械插秧又将这一技术推向机械化科学栽培...     

苎麻韧皮纤维细胞超微结构研究

对苎麻韧皮纤维细胞的超微结构进行了电子显微观察。结果表明，苎麻韧皮纤维为具隔的单细胞纤维，纤维细胞的不同部位存在着许多的外突型、内陷型和平滑型结节，节间长度为２４０－７１０μｍ，胞腔内存在大量的膜状模隔，膜间距离为６０－９０μｍ，纤维结节与胞腔隔膜没有一一对应的关系。巨原纤呈圆柱形，由圆筒形外壳和螺旋状的原纤构成，表现平滑，直径为０．２５μｍ左右，普遍存在着交织现象，大多数趋向纤维轴向排列，在胞壁