梅花鹿甲烷能代谢规律的研究

本文应用ＫＢ－１型呼吸测热装置,结合消化、代谢试验,对梅花鹿（Ｃｅｒｖｕｓｎｉｐｐｏｎ）甲烷能代谢规律进行了研究。结果表明,梅花鹿甲烷能的产生量随其采食量的增加而增加;也随着果食后时间的推移而减少,而且减少的幅度又随采食量的增加而下降;甲烷能的产生量分别占总能食入量、消化能食入量和体增热的６．６１％、８．８３％和１０．８８％;甲烷能的产生量随着日粮蛋白质水平的提高而降低,日粮蛋白质水平每提高１个百分点,甲烷能产生量就降低５８．５８ｋＪ／ｄ;分别以总能食入量（ＧＥＩ）和干物质食入量（ＤＭＩ）为自变量所建立的甲烷能（ＣＨ４Ｅ）估计分别为：ＣＨ４Ｅ（ｋＪ／ｄ）＝０．０７ＣＥＪ（ｋＪ／ｄ）－１０１．０４（ｎ＝１２,ｒ＝０．９４４,Ｐ＜０．０１）ＣＨ４Ｅ（ｋＪ／ｄ）＝９８．７８＋１．０５ＤＭＩ（ｇ／ｄ）（ｎ＝１２,ｒ＝０．９４２,Ｐ＜０．０１）     

应用FIA型微生物传感器测定谷氨酸含量的研究

目前应用酶或微生物细胞作为分子识别元件构建生物传感器测定谷氨酸含量的研究引起了广泛的兴趣,并陆续有实例报道。在这些报道中人们依据不同的酶催反应选择相应的离子选择性电极,如CO₂电极、NH₄⁺电极等,而测量对象有直接的测定谷氨酸,也有测定谷氨酸单钠的间接测定法。本文选用了可固定大量细胞的固定化细胞柱与流动注入法相结合的测量方法,并根据细胞柱的动力学模型分析动态响应曲线,计算测量结果,提高了测量精度,扩大了测量范围。     

Acid-base equilibria of air-water monolayers ofN-hexadecyl-8-hydroxy-2-quinolinecarboxamide

The surface pressure-area (-A) isotherms ofN-hexadecyl-8-hydroxy-2-quinolinecarboxamide (HHQ) monolayers at an air-water interface on subphases with different pH values were investigated. The monolayer of HHQ was expanded and unstable on acidic subphases, while it was condensed and stable on basic subphases. The acid-base equilibrium of HHQ was investigated in an aqueous dioxane solution and at the air-water interface. The association-dissociation of HHQ with H⁺ ions in the interfacial region was very different from that in the aqueous dioxane solution. Some information regarding the packing density, phase transition and degree of ionization of the head group under different experimental conditions has been obtained.     

20-羟基蜕皮酮对蓖麻蚕蛹体液免疫的调节作用(英)

本研究指出20—羟基蜕皮酮(20-OHE)参加蓖麻蚕蛹对大肠杆菌的体液免疫反应。20-OHE的作用方式是多方面的,包括提高血淋巴蛋白质含量,产生抗菌蛋白,增加溶菌酶活性,和激活原酚氧化酶系统。这表明多个免疫控制系统参与蓖麻蚕蛹体液免疫反应的可能性。     

马铃薯人工种子的研究

本研究以虎头（Ｈ）、克四（Ｋ）和Ｆａｖｏｒｉｔａ（Ｆ）三个品种的马铃薯不定芽在液体培养条件下诱导生成的微型薯为试材,经筛选后获得的大小一致的微型薯经过适度的低温处理后,用４％的海藻酸钠和２％的氯化钙溶液,在附加一定的植物激素条件下,进行人。种皮包埋形成人工种子。在无菌条件下,三个品种的人工种子萌发率均达９０％以上。在土壤中,人工种子萌发率可达６０％以上,萌发的人工种子中８０％能够形成生长发育正常的完整植株。     

REGULATORY ROLE OF 20-HYDROXYECDYSONE ON HUMORAL IMMUNITY IN THE PUPAE OF THE INDIAN SILKWORM,PHZLOSAMIA CYNTHIA RICINI*

Abstract The present study shows that 20-hydroxyecdysone(20-OHE) participates in the humoral immune responses of Philosamia Cynthia ricini, either normal or debrained pupae, to the E. coli. The mode of action of 20—-OHE is multiple. It raises hemolymph protein content, makes antibacterial proteins be produced, increases lysozyme activity, and activates prophenoloxidase system. It is possible that several immune control systems are involved.     

Kinetic study on starch hydrolysis using a glucose/maltose sensing system

Summary A dual-enzyme electrode flow injection system that can simultaneously determine glucose and maltose is used for an on-line study of starch hydrolyses catalysed by amylases. With the working system, determinations can be made every 2 minutes. A 10 L sample size with recycled back-flow minimises any loss of the reaction medium. The production, growth and decay of glucose and maltose concentrations during starch hydrolysis under various enzymatic conditions can thus be closely monitored, making it useful for the study of the catalytic kinetics of amylases and in screening and analysing enzyme systems.     

Identification of an epithelial protein related to the desmosome and intermediate filament network

Using a mAb, referred to as 08L, we have identified a protein, of M(r) approximately 140,000, associated with desmosomes of epithelial cells. The 08L antibody stained the intracellular side of lateral cell margins of monolayer epithelial cells but did not stain cell margins free of cell contact. Immunoelectron microscopy revealed that the 08L antigen was localized to the cytosolic surface of the desmosomal plaque near points of intermediate filament convergence with apparently little staining of the desmosomal plaque proper. Western blots revealed the 08L antigen to be a protein, of M(r) approximately 140,000, found in the Triton-X 100 insoluble pellet. High salt-containing buffers extracted the 08L antigen from the insoluble material. Examination of the assembly of 08L to the desmosome complex, in cells grown in low confluent culture or in calcium-switch assays, by double immunofluorescence with 08L and anti-desmoplakin antibody, revealed that 08L was recruited to morphologically identifiable desmosomes. 08L antigen may exist in a cytosolic pool prior to assembly to the cell surface. The solubility of 08L in low calcium and normal calcium conditions, however, was similar. 08L association to the desmosome was correlated with increased organization of the intermediate filament network. We suggest that the 08L antigen may be involved in the organization and stabilization of the desmosome-IF complexes of epithelia.     

Mechanism of action of the antiplatelet peptide, arietin, from Bitis arietans venom

Arietin, an Arg-Gly-Asp containing peptide from venom of Bitis arietans, inhibited aggregation of platelets stimulated by a variety of agonists with a similar IC50, 1.3-2.7.10(-7) M. It blocked aggregation through the interference of fibrinogen binding to fibrinogen receptors on platelet surface. In this paper, we further demonstrated that arietin had no significant effect on the intracellular mobilization of Ca2+ in Quin2-AM-loaded platelets stimulated by thrombin. It inhibited 125I-fibrinogen binding to ADP-stimulated platelets in a competitive manner (IC50, 1.1.10(-7) M). 125I-arietin bound to unstimulated, ADP-stimulated and elastase-treated platelets in a saturable manner and its Kd values were estimated to be 3.4.10(-7), 3.4.10(-8) and 6.5.10(-8) M, respectively, while the corresponding binding sites were 46,904, 48,958 and 34,817 per platelet, respectively. Arg-Gly-Asp-Ser (RGDS) inhibited 125I-arietin binding to ADP-stimulated platelets in a competitive manner. RGD-containing peptides, including trigramin and rhodostomin, EDTA and monoclonal antibody, 7E3, raised against glycoprotein IIb-IIIa complex, inhibited 125I-arietin binding to ADP-stimulated platelets, indicating that the binding sites of arietin appear to be located at or near glycoprotein IIb-IIIa complex. In conclusion, arietin and other RGD-containing trigramin-like peptides preferentially bind to the fibrinogen receptors associated with glycoprotein IIb-IIIa complex of the activated platelets, thus leading to the blockade of fibrinogen binding to its receptors and subsequent aggregation. The presence of RGD of arietin is essential for the expression of its biological activity. Its binding sites are overlapped with those of trigramin, rhodostomin and the monoclonal antibody, 7E3.