硬头鳟巨噬细胞的体外长期培养(简报)

鱼类的巨噬细胞和高等脊椎动物的一样,在吞灭入侵的病原体方面起着极其重要的作用。探索在体外长期培养巨噬细胞的方法,有助于研究巨噬细胞的机能。Braun-Nesje等虽已从硬头鳟(Salmo gairdneri)等鲑科鱼类的头肾中分离出大量的巨噬细胞,并在体外培养了3个月之久,但因细胞不分裂,无法传代。本研究改用组织块培养法和饲养层技术探索长期培养巨噬细胞的方法,并获得成功。迄今巨噬细胞已在体外培养22个月,传代48次。细胞的原代培养分为三组。前两组是单独的脾或头肾的组织培养;第三组是脾与头肾的混合组织培养。培养液是Leibovitz’s L-15,外加20%胎牛血清,100 IU/ml青霉素和100μg/ml链霉素。巨噬细胞的吞噬活力用酵母菌Candida     

大叶杨配囊及胚珠的形成和发育

本文应用细胞化学方法研究了大叶杨胚珠、胚囊的形成和发育过程中核酸、蛋白质及不溶性多糖的分布和消长。大孢子母细胞、大孢子四分体及功能大孢子中含较少不溶性多糖,但却含丰富的RNA和蛋白质。功能大孢子经分裂发育成八核的蓼型胚囊。四核胚囊开始积累细胞质多糖,成熟胚囊中除反足细胞外充满淀粉粒。反足细胞形成后不久即退化。助细胞具多糖性质的丝状器,受精前两个助细胞退化。卵细胞核对Feulgen反应呈负反应。二极核受精前由胚囊中部移向卵器,与卵器接触后融合形成次生核。发育早期的胚珠为厚珠心,双珠被。晚期,内珠被退化,故成熟胚珠为单珠被。四核胚囊时期,珠孔端珠心组织退化,胚囊伸向珠孔形成胚囊喙。合点端珠心组织含丰富的蛋白质和核酸,这一性质与绒毡层性质相似,可能涉及胚囊的营养运输。胚囊的营养来源于子房和胎座细胞内贮存的淀粉粒。     

乌桕桕脂中甾醇和其它成分分离鉴定

通过柱层析、薄层层析等化学方法,从乌桕桕脂中分离得到甾醇及脂肪酸酯类化合物。经气相色谱和气-质联用分析,鉴定出下列化合物:β-谷甾醇、菜油甾醇、Δ~7-豆甾烯醇、肉豆蔻酸甲酯、肉豆蔻酸乙酯、棕榈酸甲酯、硬酯酸甲酯和硬酯酸乙酯。     

蚕豆根端细胞核中微核仁的研究

以蚕豆(Vicia faba)根端分生组织细胞为材料研究了微核仁的超微结构和细胞化学特点。结果表明;微核仁是直径0.3—0.5μm 的卵圆形或球形结构。常规染色时,微核仁与集缩染色质的电子密度相仿,但两者之间在结构上没有任何联系。细胞化学研究指出,微核仁含有 RNA 和蛋白质,其结构成分主要是与核仁颗粒组分十分相似的 RNP 颗粒。报道了植物细胞核中微核仁发生于核仁的过程并对微核仁的本质和功能进行了讨论。     

新疆准噶尔盆地三个泉地区几种始新世哺乳类

本文记述了准噶尔盆地北缘三个泉地区依希白拉组中采到的踝节类、蹠行类、全齿类和恐角类化石。根据这些化石,依希白拉组的时代可能和北美中始新世勃力吉期相当。文内,通过文献分析,认为周明镇和胡长康(1956)记述的真恐角兽的前臼齿可能产自三个泉附近的依希白拉组。     

Spectroscopic studies of lipids and biological membranes: carbon-13 and proton magic-angle sample-spinning nuclear magnetic resonance study of glycolipid-water systems.

We have obtained 1H and 13C magic-angle sample-spinning (MAS) nuclear magnetic resonance (NMR) spectra of three glycosyldiacylglycerol-water (1:1, weight ratio) mesophases, at 11.7 T, as a function of temperature, in order to probe lipid headgroup, backbone, and acyl chain dynamics by using natural-abundance NMR probes. The systems investigated were monogalactosyldiacyldiglyceride [MGDG; primarily 1,2-di[(9Z,12Z,15Z)octadec-9,12,15-trienoyl++ +]-3-beta-D-galactopyranosyl- sn-glycerol]; digalactosyldiacyldiglyceride [DGDG; primarily 1,2-di[(9Z,12Z,15Z)octadec-9,12,15-trienoyl++ +]-3- (alpha-D-galactopyranosyl-1-6-beta-D-glactopyranosyl)-sn-glycerol] ; and sulfoquinovosyldiacyldiglyceride [SQDG; primarily 1-[(9Z,12Z,15Z)octadec-9,12,15-trienoyl]-2 -hexadecanoyl-3-(6-deoxyl-6- sulfono-alpha-D-glucopyranosyl)-sn-glycerol]. At approximately 22 degrees C, all three lipid-water systems give well-resoled 13C and 1H MAS NMR spectra, characteristic of fluid, liquid-crystalline mesophases. 13C spin-lattice relaxation times of the headgroup and glycerol backbone carbons of all three materials give, within experimental error, the same NT1 values (approximately 400 ms), implying similar high-frequency motions, independent of headgroup size and charge. Upon cooling, pronounced line broadenings are observed, due to an increase in slow motional behavior. For each lipid, the onset of line broadening is seen with the glycosyl headgroup, glycerol backbone, and the first two or three carbons of the acyl chains. By approximately -20 degrees, all headgroup carbon resonances are broadened beyond detection. Both galactose moieties in DGDG "freeze out" together, implying a rigid-body motion of the disaccharide unit. Upon further cooling, the bulk polymethylene chain resonances in all three systems (in both 13C and 1H MAS) broaden greatly, followed by the olefinic and allylic carbon resonances.(ABSTRACT TRUNCATED AT 250 WORDS)