吡啶甲酸铬安全性研究进展

吡啶甲酸铬作为有机铬添加剂，已成为普遍使用的铬营养补充物质。但目前尚未正式发布动物最低需要量和最高耐受量的具体数据。吡啶甲酸铬的安全性仍在研究探索之中，但得到的研究结果不尽一致。为此作者就吡啶甲酸铬的安全性研究及现有可能存在的代谢途径进行综述，以便为日后吡啶甲酸铬的研究提供理论基础。     

钴离子(Co~(2 ))对月季鲜切花生理结构的影响

在实验室常温条件下，将月季（ＲｏｓａＣｈｉｎｅｓｅｓｊａｃｑ．）鲜切花品种“萨蒙莎”置于２％蔗糖和不同浓度ＣｏＣｌ２溶液进行瓶插培养．在有蔗糖提供营养的基础上，Ｃｏ２＋可以延缓细胞膜差别透性的降低，抑制月季茎切口端和培养液微生物特别是真菌的生长，并能维持茎中央薄壁细胞和花瓣表面乳突状细胞的完整性，减少“弯颈”现象的发生．     

低温等离子种子处理研究初报

采用低温等离子种子处理技术对大豆、玉米、番茄、甘蓝种子进行不同剂量的处理，观察对这些作物生长发育及产量的影响。结果表明，在适宜剂量处理下，4种作物产量均有所提高，最高增产效果：大豆40．76％，玉米14．4％，番茄37．3％，甘蓝22．84％。处理剂量偏高或偏低时蔬菜作物表现出明显的减产趋势，而粮食作物则表现为不增产或增产不显著     

含N三臂类肽的合成

利用胺分子中氮原子成键的空间特征，接上3个含有S，N杂原子的氨基酸侧链从而合成了穴醚状含N三臂类肽，其独特的分子结构对客体识别具有重要的实践价值．     

Population Studies of Limonium stocksii (Plumbaginacea) from a Salt Desert Near the Arabian Sea Coast

Abstract

A population of Limonium stocksii was studied for one year at the upper end of Manora Creek along the Arabian Sea coast, near Karachi, Pakistan. The community was divided into three zones. Soil pH varied from 8.1 to 8.5. Soil conductivity was highest (191 dS m^?1) in September and lowest (55 dS m^?1) in June. Soil water content was relatively low and varied from 1.6% in February to 9.5% in June. Limonium stocksii maintained a persistent seed bank, which peaked at 5,887 seeds m^?2 in May. Very slow growth was observed; however, plants in the intermediate zone showed better growth than the other two zones. Stem and leaf tissue water content were affected by salinity fluctuations, but root tissue water remained unaffected. Sodium (Na⁺) and chloride (Cl^?) accumulated in stems and leaves more than other ions. Leaves also accumulated a very high amount of magnesium (Mg⁺⁺) compared to roots and stems.     

饮水高钠诱发的肉鸡腹水综合征的血液流变学特征

为查明高钠饮水与肉鸡腹水综合征的病因学关系，将２４０只健康ＡＡ肉鸡随机均分为试验Ⅰ、Ⅱ和对照３个组，从８日龄起分别饮用含Ｎａ＋为０．０６％、０．１２％和０．００％的饮水，动态对比观察各组肉鸡临床表现、血液红细胞压积（ＰＣＶ）、红细胞变形性（ＥＤ）、右心室（ＲＶ）和全心室（ＴＶ）的重量比（ＲＶ／ＴＶ）。结果表明，高钠饮水可以诱发腹水综合征；肉鸡在摄入过量Ｎａ＋时，出现肺动脉高压（ＰＨ）、ＰＣＶ增加和ＥＤ下降等血液流变学特性的改变，促进了腹水综合征的形成。     

亚硝酸盐在水生动物体内的吸收机制及蓄积的影响因素

亚硝酸盐是水产养殖系统中一种潜在的污染物，淡水鱼类通过鳃主动吸收亚硝酸盐，导致体内亚硝酸盐的浓度过高。海水鱼类对亚硝酸盐的敏感性较低，但仍可以通过肠和鳃吸收亚硝酸盐。影响亚硝酸盐在体内蓄积的因素很多，文章就亚硝酸盐在水生动物体内的吸收及蓄积的影响因素这2个方面进行了论述。     

Comparison of the response of ion distribution in the tissues and cells of the succulent plants Aloe vera and Salicornia europaea to saline stress

There exists a great variability among plant species regarding their sensitivity and resistance to high salinity in soil, and most often this variability is related with the ability of a particular plant species to regulate ion homeostasis and transport. In this study, we have investigated the effects of NaCl on growth rate, water status, and ion distribution in different cells and tissues of two succulent plants, Aloe vera and Salicornia europaea. Our results showed that the growth of A. vera seedlings was significantly decreased in response to salinity. However, the growth of S. europaea seedlings was greatly stimulated by high concentrations of NaCl. Under saline conditions, S. europaea seedlings maintained K⁺ and Ca²⁺ uptake in roots and showed a higher root‐to‐shoot flux of Na⁺ and Cl^– as compared to A. vera. Despite great accumulation of Na⁺ and Cl^– in photosynthetically active shoot cells in S. europaea, its growth was enhanced, indicating S. europaea is capable of compartmentalizing salt ions in the vacuoles of shoot cells. Aloe vera seedlings, however, showed a low transport rate of Na⁺ and Cl^– to leaves and suppressed uptake of K⁺ and Ca²⁺ in roots during NaCl treatment. Our results also implicate that A. vera may be able to accumulate Na⁺ and Cl^– in the metabolically inactive aqueous cells in leaves and, as a result, the plant can survive and can maintain growth under saline conditions.     

竹炭性能的研究进展

文章主要根据目前国内的竹炭研究进展的状况．综述了竹炭吸附性能、竹炭导电性能、竹炭改良土壤的性能、竹炭的负离子功效和竹炭的远红外功效的研究进展。