漆树透明标本制作法

本文报道了制备漆树树皮透明标本,研究漆汁道的方法。根据生漆中漆酚在漆酶作用下氧化成膜的原理,先使漆汁道中的生漆凝固,变成黑色或棕红色的条状漆膜,然后利用KOH和NH_4OH进行漂白,使树皮成为无色透明的组织,可以长期保存于二甲苯或冬青油中,或制成永久装片,以便观察研究整体漆汁道组织的形态结构及其在树皮透明标本中的数量与分布。     

漆树花器官中漆汁道的分布和发育

本文报道了漆树花器官中漆汁道的发生和发育方式。研究结果表明,萼片、花瓣和子房中漆汁道是以裂生方式产生的。但发育到一定阶段,漆汁道腔周围的分泌细胞有与漆汁道中分泌物相似的染色反应。随后,这些细胞脱入腔道,逐渐解体。与此同时,暴露在腔道周围的薄壁细胞逐渐变成分泌细胞。因此,在漆树花器官(雄蕊除外)中,漆汁道的发育是裂溶生的。     

漆树漆汁道的超微结构研究

<正> 生漆是一种优良的天然涂料,是漆树代谢过程的次生产物,由漆汁道分泌和贮芷。近年来,国内外对于漆树及其同科植物漆汁道的显微结构方面已有许多研究报道,但对我国盛产生漆的漆树(Rhus verniciflua)漆汁道的超显微结构至今尚未见报道。为此,我们以漆树树皮为材料,对其次生韧皮部中漆汁道的超微结构进行了观察,并进一步探讨生漆的形成与漆汁道细胞超微结构的关系。现将研究结果报道于后。     

漆树树皮内漆汁道堵塞现象的观察

<正> 生漆是优良的天然涂料,它是漆谢(Rhus vernicifua Stokes)代谢过程中的次生产物,由漆树体内的漆汁道分泌和贮存的。关于漆汁道在树皮内的结构、分布、长度和分枝等方面的规律,西北大学胡正海副教授等人已作了全面系统的研究。但是有关漆树树皮内漆汁道堵塞现象的观察研究,至今未见报道。现将我们的观察研究结果报道如后。     

漆树漆汁道的形态学研究(简报)

<正> 漆树(Rhus verniciflua Stokes)的漆汁道是分泌贮存生漆的场所,与割漆技术的改进,生漆的产量和质量关系密切。七十年代以来国内有关单位十分重视漆树的研究,但对漆树树皮内漆汁道的形态结构看法不一。近几年我们做了部分工作,现简要报道如下。研究用树皮主要采自贵州14个农家品种,并参考了国内生漆主产省标本、图片和资料。取用了不同树龄的胸径或主干树皮。鲜皮用FAA同定,石蜡法制片,整块树皮以氢氧化钾或氢氧化钾、甘油、水合氯醛混合透明,再以双氧水、草酸退色,甘油再透明临时封藏供观测摄影。     

漆树透明标本纵观漆汁道

漆树是我国特有的经济林木之一 ,生漆产量居于世界首位。漆汁道是累积、贮藏生漆的内分泌结构 ,由一层分泌细胞和 2～ 3层鞘细胞围成的腔道 ,遍布于漆树的各个器官。制作漆树透明标本 ,可观察到漆树体内完整的漆汁道形态结构、数量和立体分布规律。1　漆树透明标本的制作原理和方法1 1　制作原理生漆在一定条件 (温度 2 0～ 30℃相对湿度 80～ 90℃ )下 ,由于漆酶的作用 ,漆酚发生氧化 ,凝结成棕红色的漆膜 ,漆膜具有坚固性 ,耐酸碱及各种化学溶剂的特性。根据上述原理 ,人工控制温湿度条件 ,使漆汁道内的生漆凝固成漆膜 ,采取相应的技术措…     

漆汁道名释与命名

<正> 漆汁道是贮藏、累积生漆的分泌结构。属于裂生形成的分泌道(Secretory Canal)。横切面上观察由1～2层分泌细胞(Secretory Cell)和2～3层小型薄壁细胞组成的鞘围成的道(Canal)或腔(Cavity);弦切面上稀见分枝。分枝状况及道的长短不一,大多数是沿着茎的长轴方向近乎平行伸展的。近年来生漆生产的发展促进了生漆科学研究领域不断扩大,成果不断增加。但是也     

漆树各器官内乳汁道种类及形态学特征

本文报道漆树根、茎、叶、花、果及随部乳汁道种类及形态特征,计三类14种。其中8种为首次发现和命名。各器官的乳汁道形态均有一定差异。     

漆树科植物种子油

<正> 漆树科(Anacardiaceae)为生漆液的母树。漆树科植物各器官都蓄有不同分量的漆汁,它们在干燥后成膜,可形成漆膜,都是优良的成膜物,其种子油为名贵的油脂,在工业化上有如下的品种:1.漆树种子油漆树种子,风干可以直接供食用。漆树种子的成分如下表:     

乙烯利——增加漆树割漆产量的激素

生漆是从漆树皮部割取的漆汁,属天然漆,是我国著名特产,历史上就曾以“涂料之王”著称。我国劳动人民对于生漆的生产、加工和利用,已有三千多年的悠久历史,世界闻名艺术精美的中国漆器,是我国传统的     

绿脓杆菌重组毒素分泌表达的初步研究

目的分析绿脓杆菌重组毒素的分泌表达机理。方法将所构建的6种绿脓杆菌重组毒素的分泌表达质粒,即pET-20b-IL-1023-57-PE40、pET-20b-EGF-PE40、pET-20b-LHRH-PE35、pET-20b-EGF-PE38、pET-20b-MSH-PE40和pET-20b-LHRH-PE40分别转化至Rosetta(DE3)中,进行IPTG诱导表达。结果只有LHRH-PE40和LHRH-PE35能分泌表达。LHRH-PE35表达产物经Westernblot检测,可被特异抗体识别。经DNAStar和ANThewin蛋白分析软件对6种PE重组毒素性质进行比较分析发现,并不是所有PE重组毒素融合信号肽序列后,就能分泌表达,其中导向部分的性质决定了PE重组毒素是否分泌表达。结论对绿脓杆菌重组毒素的分泌机理已有初步了解。     

表面活性剂对氯离子选择性电极测量值的影响

该文研究了两种非离子表面活性剂、两种阴离子表面活性剂、两种阳离子表面活性剂和一种两性表面活性剂对氯离子选择电极测定值的影响规律。讨论了表面活性剂产生干扰的原因，并提出了抑制干扰的方法。     

The effects of fat upon the rates of digestion in the human stomach of meals of high protein content

Summary Results of the two series of experiments on four human subjects who were representative of normal gastric secretory and motor functions have shown that, under the experimental conditions, neither moderate nor large amounts of fat, added to lean beef either by physical mixing or by cooking, affect the gastric secretory response to the meals. In other words, the addition to lean beef of fat as a hydrogenated vegetable oil did not diminish the capacity of the gastric juice to digest protein. Also, the addition of moderate or large amounts of fat to the lean beef did not retard the evacuation from the stomach of either the protein or the fat of the meal. This work was supported by a grant from Lever Brothers Company, Cambridge, Massachusetts. Presented at the 20th annual fall meeting, American Oil Chemists’ Society, Oct. 30–Nov. 1, 1946, in Chicago, Ill.     

Mathematical modelling of essential oil SFE on the micro-scale—Classification of plant material

This article reports the achievements of the micro-scale (secretory-structure-scale) mathematical modelling of essential oil isolation by supercritical carbon dioxide. Some new experimental and modelling results are presented. The improved model for the supercritical fluid extraction from the glandular trichomes (peltate glands) is introduced. According to the behavior of plant secretory structures during the extraction as well as according to the modelling results, plant material was classified according to the dominant resistance to mass transfer during the extraction process. External mass transfer was the rate limiting step in the extraction from plants with secretory ducts and secretory cavities of citrus family. In the case of extraction from secretory cells, internal diffusion was the rate limiting step. In the extraction from glandular trichomes, external mass transfer, as well as diffusion through the gland membrane influenced the process.     

磷肥的环境影响及管理

介绍两种磷肥生产工艺,即WPPA与硝磷工艺,阐述了两种工艺的技经特征及其对环境的影响,提出了管理办法。     

乙肝病毒前S1基因与截短C基因穿梭表达载体构建

目的构建HBV前S1基因和截短C基因分泌型大肠杆菌和分枝杆菌穿梭质粒。方法以含HBV基因组质粒pCP10序列为模板,PCR扩增前S1基因和C基因截短片段,依次克隆至分泌型穿梭表达载体pDE22,电穿孔转化法将重组质粒导入耻垢分枝杆菌,经潮霉素抗性筛选及PCR鉴定,阳性克隆热休克诱导表达,表达产物经SDS-PAGE分析。结果扩增到了预期长度的2个目的基因,构建了分泌型穿梭载体,SDS-PAGE分析可见相对分子质量约23000蛋白表达条带。结论已成功构建耻垢分枝杆菌分泌表达前S1基因和截短C基因的穿梭载体,为研究含前S基因和截短C基因的重组BCG疫苗奠定了基础。     

Oleate acutely stimulates the secretion of triacylglycerol by cultured rat hepatocytes by accelerating the emptying of the secretory compartment

The acute effects of addition of oleate on the rate of triacylglycerol (TAG) secretion by cultured rat hepatocytes were studied by monitoring the use of endogenous (¹⁴C-prelabeled) acyl moieties and exogenous (³H-labeled) oleate for the synthesis of secreted TAG simultaneously. Inclusion of exogenous oleate in the medium stimulated the secretion of the endogenous ¹⁴C-labeled acyl moieties by 55–100%. To find out whether the stimulation was due to increased endogenous TAG mobilization or an increased rate of processing of TAG within the endoplasmic reticulum (ER) secretory machinery, use was made of the inhibition of apolipoprotein B (apoB) synthesis (but not degradation) by Ca²⁺ mobilization from the ER. Inhibition of apoB synthesis stopped entry of acyl moieties (from endogenous and exogenous sources) into the secretory pathway. However, even when entry of acyl moieties into the secretory pathway was totally inhibited, exogenous oleate was still able to stimulate (twofold) the secretion [¹⁴C]TAG, indicating that oleate stimulates the emptying of prelabeled TAG from the secretory compartment at a point distal to apoB synthesis and nascent particle formation. These data indicate that exogenous oleate, besides providing additional acyl moieties for incorporation into secreted TAG, stimulates the secretion of endogenous TAG in a manner (i) that is independent of effects on apoB synthesis and/or degradation and (ii) that involves the enhanced processing of TAG resident within the ER secretory pathway.     

复合吸附剂吸附废水中的重金属离子的动力学研究

采用枯草芽孢杆菌活菌体、石英砂和由二者组成的复合吸附剂对废水中的Cu2+、Zn2+和Cd2+离子分别进行了吸附动力学测试,并采用以R itch ie速率方程为基础的3种吸附动力学方程对吸附动力学数据进行校验。吸附动力学数据均能基本吻合单层吸附模型、改进双层吸附模型和R itch ie双层吸附模型,其中后两者与实验数据吻合更好;双层吸附模型能更好地描述活菌体对3种重金属离子的吸附过程;对3种吸附剂吸附3种重金属离子的动力学过程进行了比较,结果显示复合吸附剂与活菌体吸附剂对3种离子的吸附过程一致,都是快速过程。     

One‐step production of 2,3‐butanediol from starch by secretory over‐expression of amylase in Klebsiella pneumoniae

BACKGROUND: 2,3‐Butanediol (2,3‐BD) is a valuable chemical that can be biosynthesized from many kinds of substrates. For commercial biological production of 2,3‐BD, it is desirable to use cheap substrate without pretreatment, such as starch. However, there have been few reports on the production of 2,3‐BD directly from starch. RESULTS: In this work, gene malS coding for α‐amylase (EC 3.2.1.1) precursor was inserted into plasmid pUC18K, and secretory over‐expression of α‐amylase was achieved by engineered Klebsiella pneumoniae. The extracellular recombinant amylase accelerated the hydrolyzation of starch, and one‐step production of 2,3‐BD from starch was carried out by engineered K. pneumoniae. A 2,3‐BD concentration of 3.8 g L^?1 and yield of 0.19 g 2,3‐BD g^?1 starch were obtained after 24 h fermentation. CONCLUSION: The one‐step production of 2,3‐BD from starch was achieved by secretory over‐expression of amylase in K. pneumoniae. This would simplify the process and reduce the production cost considerably by enabling use of starch with minimal pretreatment. Copyright © 2008 Society of Chemical Industry     

关于建筑反射隔热涂料应用中的几个问题

建筑反射隔热涂料具有透明型和不透明型两类以及水性和溶剂型等产品品种。这两类涂料在夏热冬冷和夏热冬暖地区应用可以取得良好的节能效果。本文从应用技术角度介绍了这两类涂料的反射隔热原理、涂料种类、性能特征、应用状况、应用技术和应用前景等。