添加不同类型脂肪酸对罗非鱼肝脏原代细胞内脂类代谢相关基因表达的影响

初步探索了罗非鱼肝脏原代细胞分离、纯化的方法,并在此基础上研究培养基中外源添加不同饱和度的脂肪酸(16:0,18:1 n-9,18:2n-6,20:4 n-6,20:5 n-3和22:6 n-3)对其与脂类代谢相关基因(LPL、MDH和PPARα)mRNA表达的影响.结果表明:60 g,2 min,1次和30 g,2 min,2次的离心条件获得较高细胞产量及纯度;随脂肪酸不饱和程度的增加LPL和PPARαmRNA表达均呈现明显的上升趋势,而MDH则波动性较大.     

过渡金属催化的2,3-联烯酸环化合成γ-丁烯酸内酯

γ-丁烯酸内酯是一类具有重要潜在活性的化合物.发展了二价钯催化的2,3-联烯酸和(ω-1)-烯基卤化物的偶联关环反应.反应经过了二价钯催化的氧钯化-碳钯化,重复的去钯氢化/钯氢化及β-脱卤钯化反应.同时还发展了两种联烯之间的二聚环化反应,两分子2,3-联烯酸的反应生成二丁烯酸内酯,2,3-联烯酸与1,2-联烯酮反应则生成呋喃基取代的γ-丁烯酸内酯.     

Production of conjugated linoleic acids by Lactobacillus plantarum strains isolated from naturally fermented Chinese pickles

Naturally fermented pickles harbour many lactic acid bacteria (LAB). Forty-three LAB strains with conjugated linoleic acid (CLA)-producing ability were isolated from three naturally fermented pickle brines. Of these isolates, lp15 identified as Lactobacillus plantarum by API 50 CHL system and full-length 16S rDNA sequence analysis exhibited the highest CLA-producing ability (26.1% conversion) at 48 h in de Man Rogosa Sharpe (MRS) broth in the presence of 100 μg/ml of linoleic acid (LA). Compared to other strains, L. plantarum strain lp15 showed the highest tolerance upon increased levels of LA in the medium, i.e., up to 600 μg/ml. This strain converted about 25% of LA into CLA isomers [predominantly cis-9, trans-11 CLA (9-CLA) and trans-10, cis-12 CLA (10-CLA)], of which 75% was 9-CLA. Interestingly, though the conversion rate of LA into CLA by lp15 remained stable between 100 to 600 μg/ml LA levels in the medium, it dropped sharply at 1000 μg/ml. Taken together, the lp15 strain displayed relatively high LA tolerance with higher conversion rate, which implies that this strain is a valuable candidate for enhancing the CLA content in food-sources like pickles.     

Comparative analysis of RBC membrane fatty acids, proteins and glycophorin in patients with heterozygous beta thalassemia and iron deficiency anemia

Membrane lipid and protein composition was compared in erythrocytes from iron deficiency anemia (IDA) and heterozygous beta thalassemia patients. The study was planned to correlate the influence of iron deficiency with the intrinsic defect of the heterozygous condition on the membrane structural integrity as well as to investigate whether there are differences in membrane changes between the two conditions. Results indicate high levels of saturated fatty acids and low unsaturated fatty acids in both disorders although arachidonic acid and the unsaturation index were lower in heterozygous thalassemia than IDA. Nevertheless, neither of the conditions provoked any alterations in membrane protein or glycophorin suggesting alterations in the lipid moiety only. Present findings indicate that irrespective to the etiology, both, iron deficiency and the heterozygous condition show a common pattern of lipid derangement, which may in turn result in increased membrane rigidity and decreased cellular deformability.     

多元酸碱滴定中几个问题

使用酸碱反应的条件稳定常数和终点误差公式,讨论了多元酸碱滴定中的几个理论问题,方法简明可靠,用于多元酸碱滴定教学中,结果满意     

鹿血和鹿血酒中的有效成分分析(英文)

本文对梅花鹿体血和茸的外现特征进行了比较,并对两者的血清蛋白质、氨基酸及无机元素含量进行了测试比较,为鹿血产品的开发提供科学依据。并对鹿血酒中的氨基酸和微量元素进行了测定。     

运动与氨基酸的代谢

氨基酸是构成机体蛋白质的基本原料,某些氨基酸具有特殊的营养功能,尽管氨基酸在运动过程中提供的能量很少,但它却与运动能力有着密切的关系。因此,阐述与运动能力有密切关系的氨基酸的代谢及其功能具有重要的意义。     

Instructional Misconceptions in Acid-Base Equilibria: An Analysis from a History and Philosophy of Science Perspective

The implications of history and philosophy of chemistry are explored in the context of chemical models. Models and modeling provide the context through which epistemological aspects of chemistry can be promoted. In this work, the development of ideas and models about acids and bases (with emphasis on the Arrhenius, the Brønsted–Lowry, and the Lewis models) are presented. In addition, misconceptions (alternative and instructional ones) on acid-base (ionic) equilibria are examined from the history and philosophy of science perspective. The relation between the development of the models and students misconceptions are investigated. Finally, the hypothesis that history and philosophy could help educators anticipate students misconceptions is examined.     

人工饲料蛋白质含量与桑蚕（Bombyx mori）对氨基酸的吸收

本试验用５种脱脂大豆粉和纤维素粉含量不同的人工饲料饲养５龄雌蚕。结果表明随着饲料蛋白质含量从９．１２％增至３７．１８％，每头蚕的氨基酸排出量从５４．９２增至２５９．８２ｍｇ。但蚕体对Ｌｅｕ、Ｐｈｅ、Ｖａｌ、Ｔｈｒ、Ｈｉｓ、Ｇｌｕ等氨基酸的吸收率则随饲料中蛋白质含量的增加而降低。而蚕体对Ａｒｇ、Ｌｙｓ、Ａｌａ、Ｉｌｅ、Ｇｌｙ、Ｐｒｏ、Ａｓｐ的吸收率及对所测１６种氨基酸的平均吸收率，则均以饲料蛋白质含量为１６．１４％时为最高。蚕体对氨基酸的吸收与氨基酸性质有关，吸收率依次为：碱性＞中性＞杂环＞酸性。