六种鱼腥藻在大量培养中的生产率和适应性与营养成分比较

连续两年对鱼腥藻的六个品系进行了大量培养比较研究,在长江中下游气候条件下,HB1042和HB1105具有稳定的生产性能,5月下旬至九月中旬123d内,平均有效生长分别为114和100d;其次是HB1058,HB686和HB1017,平均有效生长天分别为73,58和71d;HB13适应性较差。生物量生产率在5月下旬、6月中旬至9月中旬较高,除HB13外,平均都在10g干重/m~2/d以上或接近10g/m~2/d。在不同的季节它们表现出了各自的最高生物量生产率。据此,提出了逐月逐旬采取藻种搭配生产,以获得最高生物量生产率的配合关系。营养成分分析表明它们的蛋白质含量在40％左右;氨基酸组成合理,除某些种类的含硫氨基酸略低外,都符合FAO/WHO的标准。     

用纸浆代棉花合成CMC

羧甲基纤维素(CMC)系天然纤维素的衍生物。它是由天然纤维素分子上引入强极性羧甲基钠而得到的。我们采用纸浆为原料替代棉花生产CMC,测试了其性能,并讨论了反应温度、反应时间和碱用量对粘度的影响。结果表明:此法简化了工艺,原料来源广泛,产品性能优良,成本低,能满足使用要求。     

Conversion of 15-hydroxyeicosatetraenoic acid to 11-hydroxyhexadecatrienoic acid by endothelial cells

Cultured endothelial cells take up 15-hydroxyeicosatetraenoic acid (15-HETE), a lipoxygenase product formed from arachidonic acid, and incorporate it into cellular phospholipids and glycerides. Uptake can occur from either the apical or basolateral surface. A substantial amount of the 15-HETE incorporated into phospholipids is present in the inositol phosphoglycerides. 15-HETE is converted into several metabolic products that accumulate in teh extracellular fluid; this conversion does not require stimulation by agonists. The main product has been identified as 11-hydroxyhexadecatrienoic acid [16:3(11-OH)], a metabolite of 15-HETE that has not been described previously. Formation of 16:3(11-OH) decreases when 4-pentenoic acid is present, suggesting that it is produced by beta-oxidation. The endothelial cells can take up 16:3(11-OH) only 25% as effectively as 15-HETE, and 16:3(11-OH) is almost entirely excluded from the inositol phosphoglycerides. These results suggest that the endothelial cells can incorporate 15-HETE when it is released into their environment. Through partial oxidation, the endothelium can process 15-HETE to a novel metabolite that is less effectively taken up and, in particular, is excluded from the inositol phosphoglycerides.     

To early distinguish neonatal transient leukemoid proliferation from congenital leukemia by in vitro cell growth

To differentiate neonatal transient leukemoid proliferation from congenital leukemia at an early stage is often difficult. Bone marrow culture is found to be helpful in this aspect. A normal in vitro growth pattern suggests transient leukemoid proliferation, while an abnormal growth pattern indicates congenital leukemia. A neonate who manifested with pictures mimicking acute myeloblastic leukemia (M1), had a karyotype of 46, XY/46, XY, i(21 q). However, the in vitro growth pattern was normal and so only supportive treatment was given. All the leukemoid manifestations disappeared several months later and he is now a healthy 2 year old boy remaining in complete remission. A second neonate who also displayed features of acute myeloblastic leukemia (M2), had a karyotype of 46, XY/47, XY, + 21 and abnormal in vitro growth pattern. This neonate died at 18 days of age.     

豚鼠冰水游泳应激后血浆、肾上腺髓质和脑内组织的亮—脑啡肽含量变化

豚鼠冰水游泳应激3min后,用放射免疫法测定血浆、肾上腺髓质和脑内三个脑区组织的亮—脑啡肽(Leu-enkephalin,LEK,)含量和血浆的血管紧张肽Ⅱ(Angiotensin Ⅱ,ATⅡ)浓度变化。结果表明:在冰水中游泳应激组豚鼠的血浆、肾上腺髓质、下丘脑和纹状体组织的LEK含量和血浆的ATⅡ浓度,均较对照组豚鼠明显升高(P值均<0.01)。提示:豚鼠在冰水中紧张、剧烈游泳后,可能激活了中枢神经和周围组织内的脑啡肽能神经元和血管紧张肽原酶—血管紧张肽Ⅱ系统,从而促进LEK和ATⅡ的释放增加。     

伸展素在黄瓜胞壁中的转化及其与羟脯氨酸和异联酪氨酸的关系

用~(14)C-Pro和~3H_2-Tyr离体暗培养黄瓜子叶,发现细胞质、SECW和RCW中的Hyp/Pro和Idt/Tyr都随时间呈线性增加。这两种比值后两者高于前者,而两种比值增加速度之比在胞质部分最大、RCW中最小。表明在胞质和胞壁中都有Pro羟化和Tyr异联化过程,但羟化作用主要发生在胞质中,异联化主要在RCW中。 理化处理(高渗溶液和CHM)和放射性示踪证明胞质中存在HRGP库;它被分泌到胞壁后,先以离子键与壁结合,后转变为共价键与壁结合的伸展素。