人肥大细胞类糜蛋白酶序列结构分析及B细胞表位预测

根据肥大细胞Chymase的氨基酸序列，借助ProScale服务器，采用Hopp＆Woods的亲水性方案、Janin可及性参数、Welling抗原性参数及吴氏综合预测方法对肥大细胞类糜蛋白酶的二级结构及B细胞表位进行预测．结果推测最有可能的B细胞表位位于类糜蛋白酶的N端第5～12区段、第94～101区段、第172～179区段和第199～206区段内或它们的附近．本研究结果有助于确定肥大细胞类糜蛋白酶的B细胞表位，可为深入研究类糜蛋白酶的结构与功能及新型抑制剂的设计提供线索．     

大型起重桅杆的电测试验

介绍大型起重桅杆的电测试验方法，给出两个桅杆的试验主要结果，并作了评价。     

Production of active and passive anaphylactic shock in the WBB6F1 mouse,a mast cell-deficient strain

Summary The role of mast cells in active and passive anaphylactic shock was examined using the WBB6F₁ mouse, a genetically mast cell-deficient strain. Lethal anaphylactic shock occurred at high incidence rates in mice actively sensitized to bovine serum albumin (BSA). The reaction was specific to BSA since the shock could not be elicited by human or guinea pig serum albumin in these animals. Lethal shock could be prevented by CV-3988 but not by cyproheptadine, which suggests that the shock is mediated by PAF but not by histamine and serotonin. Similarly, lethal shock was provoked by homologous antigens in mice which had been passively sensitized with allogeneic anti-benzylpenicilloyl (BPO) IgG₁ monoclonal antibody or with allogeneic or xenogeneic anti-BSA antiserum, but not in those sensitized with allogeneic anti-BPO IgE monoclonal antibody. These findings suggest that mast cells are not necessarily required for anaphylactic shock in the mouse.     

海拉尔盆地泥岩盖层演化过程及封盖机理探讨

文章从海拉尔盆地泥岩成岩及有机质成烃演化出发，研究了泥岩形成有效盖层的历史，提出了位于油气大规模形成期前或成熟初期的泥岩处于埋深８００～１５００ｍ时为最优封盖期（ＧＳＴ期）。利用盆地泥岩盖层的埋深并结合其它地质资料，由ＧＳＴ期观点评价了海拉尔盆地中两套区域性盖层目前的有效封盖性。最后对盆地中处于不同演化阶段的泥岩盖层的封盖机理进行了探讨，指出该盆地泥岩盖层具３种封闭机理。     

Nitric oxide inhibition intensifies cold-restraint induced gastric ulcers in rats

Treatment 20 min beforehand with an inhibitor of nitric oxide (NO) synthesis, N^W-nitro-l-arginine methyl ester (L-NAME) (12.5, 25, 50 or 100 mg/kg, s.c.), dose-dependently intensified gastric glandular mucosal ulceration produced by cold-restraint stress. Hexamethonium (20 mg/kg) or atropine (1 mg/kg) pretreatment s.c. 20 min before stress strongly antagonised stress-evoked ulceration, as well as the ulcer-potentiating effects of L-NAME when either cholinoceptor antagonist was given concurrently with the NO inhibitor. Stress-induced mast cell degranulation was not worsened by L-NAME pretreatment. The findings suggest that NO could confer partial protection against stress-induced gastric ulcer formation; its activity is triggered off by the ulcerogenic mechanism of stress.     

桅杆天线基座整体提升施工风稳定性分析

对桅杆结构风载作用下静力整体稳定进行非线性分析,研究桅杆天线基座整体提升施工的风稳定性.基于桅杆结构的非线性平衡方程,应用ANSYS软件进行结构分析.采用特征值屈曲方法求得桅杆失稳载荷的数值解上限后,以此作为非线性屈曲分析的给定载荷,在渐进加载达到此载荷前,求得非线性失稳临界解,即该基座整体提升时的稳定安全系数,及其后屈曲路径.     

蟾蜍消化道肥大细胞的观察

采用3种不同的固定方法、2种甲苯胺蓝染色方法,对蟾蜍胃和小肠的肥大细胞(mast cells,MC)进行了研究.结果表明,蟾蜍胃和小肠中均有MC分布;MC呈长梭形、圆形、卵圆形、不规则形,主要存在于粘膜固有层或粘膜下层内,并且有围绕血管、腺泡分布的趋向;胃的固有层内MC少于粘膜下层,小肠固有层内MC多于粘膜下层;胃和小肠肌层中的MC都较少.3种固定方法中,用Carnoy液固定效果最好.在快速甲苯胺蓝染色法中,组织结构清晰可辨,MC易定位,呈紫红色;在常规甲苯胺蓝染色法中,MC不易定位,被染成蓝色.     

桅杆结构模型静力试验分析

文章根据我国荷载规范对风荷载计算的规定 ,应用风荷载最不利作用原理 ,模拟静风力在桅杆模型上几个最不利位置施加静荷载 ,在不同的加载方向、不同大小静荷载作用下进行静力试验 ,测出若干节点的应变情况及各纤绳张力的增量 ,分析其间的相互关系 ,得出了桅杆在静力荷载作用下的力学特性。     

Smallest zinc quantities affect the histamine release from peritoneal mast cells of the rat

Summary Seven individual 0.025-mg doses of zinc administered as lactose tablets on consecutive days, significantly increase histamine release from peritoneal mast cells of the rat. Seven individual doses of 0.25 g cause a somewhat smaller, though still very pronounced increase in the release in comparison with zero control.Acknowledgments. We thank Ms T. L. Pham and Ms K. Löppen for their technical assistance.