亚麻籽胶的胶凝性质

采用流变学法测定了亚麻籽胶溶液的胶凝点、熔化点，并采用质构仪、扫描电镜和原子力显微镜等手段研究了影响亚麻籽胶凝胶强度的因素，结果表明亚麻籽胶具有胶凝性，它能形成一种热可逆的冷致凝胶，亚麻籽胶溶液的胶凝点低于其凝胶的熔化点，且亚麻籽胶溶液的胶凝点及其凝胶的熔化点均随冷却的起始温度的升高而升高。亚麻籽胶浓度、溶解温度、pH、NaCl、CaCl2及复合磷酸盐能影响亚麻籽胶的凝胶强度，亚麻籽胶的凝胶强度随着浓度的增加及溶解温度的升高而增强；在pH6～9的范围内，亚麻籽胶的凝胶强度达到最大；NaCl和复合磷酸盐可以降低亚麻籽胶的凝胶强度，低浓度（〈0．3％）的CaCl2可以增强亚麻籽胶的凝胶强度，而高质量分数（〉0．3％）的CaCl2能降低亚麻籽胶的凝胶强度。     

Microvasculature of bone

The three dimensional vascular microarchitecture of mercox resin on the lateral surface of parietal bone in Wistar strain adult male rats (b. w. 260–350 g.) was studied in relation to bone formation by SEM observation of corrosion casts. The microarchitecture was a single layer of network composed of precapillary artery, capillary and postcapillary vein, which were serpigious, sometimes joined with the vein from the vascular foramen of bone. The meshes of this network, which were irregular and varied in size, existed apart from the bone surface. According to the report of Iwaku and Ozawa (1986), it was reported that the vascular microarchitecture of the bone surface was very changable during the process of bone remodeling and this network, which was shown on the flat bone surface in this study, was very similar to one in the resting phase and/or the period in which the bone formation further advanced. From these facts and the morphological features of the bone surface observed here by SEM, it is suggested that this vascular network was closely related with the resting stage and/or the period in which bone formation further advanced in bone remodeling.     

环孢素A体外抗曼氏血吸虫雄虫的电镜观察

MF1小鼠感染曼氏血吸虫六周后,经主动脉和门静脉灌注收虫.配对的成虫暴露在不含环孢素A及分别含有1微克/毫升、10微克/毫升、20微克/毫升的环孢素A的199型培养液中体外培养.药物导致的虫体损害分别作扫描电镜和透射电镜观察.药物作用后,雄虫外质膜损伤,外皮层基质出现水肿和空泡,分泌体减少.进行性表皮损害、肿胀以及皮(?)缺损最终导致皮质膜和合胞体的崩溃.本结果表明,环孢素A抗曼氏血吸虫的作用方式是直接的.而外皮质似乎是药物首先攻击的部位.     

Er,Cr:YSGG激光刮治龈下牙石的效果观察

目的:探讨Er,Cr:YSGG激光刮治龈下牙石的效果.方法:选取6颗新近拔除的有明显龈下牙石的牙周病患牙.用Er,Cr:YSGG激光照射刮治牙石区.扫描电镜(SEM)观察照射前后照射区表面形态,评价去除牙石的效果.结果:SEM可见照射前区域有污物、膜性物质、牙石等附着其上;照射后此区牙石及钙化物去除干净,根面平坦,无牙本质小管暴露及熔融、炭化改变.结论:低能量输出、小角度照射既能有效去除根面病变组织又不使牙本质小管暴露.     

我国3属10种蚊幼虫颏光镜与扫描电镜形态特征研究

本文首次报告了我国脉毛蚊属、库蚊属和按蚊属10种蚊Ⅳ龄幼虫颏的光镜与扫描电镜的形态特征。结果表明,利用颏进行分类鉴定,在某些种类具有一定的意义。     

剌痛伊蚊四龄幼虫扫描电镜观察

本文报告了刺痛伊蚊在电镜下发现触角上的小刺系由小刺窝长出,多为单生小剌,双生小刺偶见,组成复眼之小眼乃呈不规则的圆或椭圆形,小眼间散在棍棒状的绒毛,孔缘瓣上的腹瓣上9号毛粗壮呈钩状,并散在几个大小不等的小隆起。     

金属基底上聚合吡咯的电化学及电镜表征

用循环伏安法研究了吡咯在不同金属基底不同支持电解质中的聚合过程，对不同基底上制备的聚吡咯膜进行了电化学、扫描电镜、表面能谱等方面的研究，考察了聚吡咯膜电极对ＮＯ_３－离子的电位响应情况，结果表明，不同基底不同支持电解质在不同的吡咯浓度中表现出各异的伏安行为，经电化学处理的聚吡咯膜电极均对ＮＯ_３－呈Ｎｅｒｎｓｔ响应，扫描电镜观察表明除Ｐｔ基底外在其它基底上制备的聚吡咯膜均呈颗粒性球状堆集。     

Drawn gelatin films with improved mechanical properties

Chain anisotropic distribution in gelatin films has been obtained by uniaxial stretching at constant relative humidity, followed by air drying and successive cross-linking with glutaraldehyde. The drawn samples have been characterized by mechanical tests, differential scanning calorimetry and scanning electron microscopy. The Young’s modulus, E, and the stress at break, σ_b, increase linearly with the draw ratio and reach values which are about five times those characteristic of undrawn samples. Furthermore, on stretching the alignment of the gelatin strands along the direction of deformation increases while the thickness of the layers decreases significantly. The renaturation level, that is the fraction of gelatin in a collagen-like structure, has been calculated as the ratio between the melting enthalpy of gelatin samples and that of tendon collagen. The results indicate that the improvement of mechanical properties achieved by drawn gelatin is closely related to the renaturation level. The experimental approach utilized to induce segmental orientation in gelatin films, allows to obtain anisotropic materials with improved mechanical properties in the direction of deformation, and can be usefully applied in the preparation of biomaterials.     

密质骨损伤机理的实验研究

用Ｉｎｓｔｒｏｎ试验机对新鲜夫股骨密质骨试样进行一维拉伸实验研究，利用实验结果对由平行粘弹性杆系统建立的密质骨损伤本构模型待定参数进行拟合，获得较高的相关系数和较好的显著性水平。     

Mechanisms of the CYNAP phenomenon: evidence in the Bw49/Bw50 model for epitopes with different spatial orientation of antibody

The mechanism of the cytotoxic-negative, absorption-positive (CYNAP) phenomenon was studied using the model of the Bw49/Bw50 split of the BW21 antigen. Anti-Bw49 antibody bound 60% as well to Bw 50 as to Bw49 cells; however, even at a cytotoxic titer of 64 against Bw49 cells, the antibody was not cytotoxic to Bw50 Cells. At equal numbers of antibody molecules bound, the anti-Bw49 antibody activated C4 and C3, and induced lysis for Bw49 but not for the Bw50 cells. These data are consistent with a model in which different spatial orientations for shared epitopes can account for CYNAP reactivity for at least some selected Bw4/Bw6-associated splits of B locus antigens.