睾丸间质细胞—研究自体吞噬的一种正常细胞模型

In the present study, we tried to estimate, in a semiquantitative way, the relative frequency of the autophagic activity in various cell types under physiological condition. The results indicated that the highest activity appeared to be in the Leydig cells of rat testes. Autophagosomes were frequently observed in electron microscope photographs of Leydig cells, which provide a good model to study the autophagocytosis in normal cells. The autophagic process in Leydig cells was observed with the electron microscope in preparations treated to show CMPase activity. The mode of formation of autophagosomes in Leydig cells can be divided into three steps. Step 1, flattened membranous elements expand to enclose a small cytoplasmic territory to form pre-autophagosome. Step 2, The double membrane profile of the pre-autophagosome then completely encloses the cytoplasmic territory to form early autophagosome in which structurally normal organelles are contained. Step 3, the transformation of an early autophagosome into a late one is accompanied by the loss of one of the two delimiting membranes, the partial disintegration of the enclosed content and simultaneous acquisition of acid phosphatase activity. The enzymatic reactivity is acquired following a close association with the lysosomes. The late autophagosome then reaches the cell surface and appear to exocytose their residual content.     

养殖对虾的纤毛虫病害

纤毛虫原是养殖水体正常的生态种群,关于纤毛虫与对虾(Penaeus)的生态关系,早有过报道。七十年代初,随着对虾养殖业在世界范围内的蓬勃兴起,纤毛虫对养殖对虾的危害才逐渐地引起人们的注意。1973年,美国学者Johnson和Overstreet分别报道在池养的白对虾(Penaeus setiferus)和褐对虾(P. aztecus)体表发现大量聚缩虫(Zoothamnium sp.)附着,指出当溶解氧水平降到3—2.6ppm时,对虾死亡率很高。在这以后,美国著名无脊椎动物病理学家Lightner(1975a,1975b)继续报道他在其他对虾,例如桃红对虾(P. duorarum),蓝对虾(P.stylirostris)等发现的纤毛虫病,并对病理作了初步的分析。     

蜘蛛染色体的常规制片技术

目前国内尚未见到有关蜘蛛染色体常规方法的报道。作者参考国外学者的方法,经过实践,并加以补充改进,掌握了蜘蛛染色体的常规制片技术。并且从制取的染色体片中得知,大腹园蛛的染色体数目为32条,横纹金蛛的染色体数目为26条。     

L-亮氨酸发酵的研究

钝齿棒状杆菌(corynebacterium crenatum)L-421是一株能产大量亮氨酸的突变株,它是从Corynebactcrium crenatum Asl.1004菌株经NTG和快中子处理后获得的突变株。在含有葡萄糖、硫酸铵和尿素的培养基中,在2000升罐上,30℃发酵40小时,产亮氨酸可达20g/L。经强酸型阻离子交换树脂提取,收率可达40%以上,并得到符合美国药典85年21版标准的精品。发酵提取工艺简单,适于工业化生产。