双歧杆菌活菌制剂对烧伤鼠肠源性感染的预防作用

本文以３０％烫伤同时口服抗生素,喂饲双歧杆菌制剂的大鼠为模型,将Ｗｉｓｔａｒ大鼠分为烧伤治疗组,烧伤对照组及正常对照组。并于伤后２４、４８、７２、９６小时分别观察盲肠内容物菌群,粘蛋白,分泌型免疫球蛋白Ａ（ＳＩｇＡ）;肠道细菌移位率;腔静脉内毒素含量。结果发现烧伤后肠道菌群有不同程度的变化,念珠菌迅速过度生长、厌氧菌下降、肠内需厌氧菌比例严重失调,治疗组中粘蛋白含量,肠道细菌移位率均明显小于烧伤对照组;而ＳＩｇＡ含量则高于对照组,菌群改变较对照组轻。故认为双歧杆菌制剂有助于预防烧伤肠源性感染的发生。     

肺炎链球菌在复发性阿弗他溃疡中定居部位的变化

目的探讨复发性阿弗他溃疡表面细菌的定居状态.方法 分别对病例组溃疡灶及对照组唇部粘膜进行了细菌学分离对比研究.结果 病例组溃疡灶以肺炎链球菌为主,而对照组唇部粘膜以甲型溶血性链球菌为主. 结论复发性阿弗他溃疡患者中肺炎链球菌定居部位发生改变.     

TRANSLOCATION OF PHOTOSYNTHATE IN THE BROWN ALGA NEREOCYSTIS

Translocation of photosynthates was found to occur when blades of Nereocystis were illuminated in the presence of C¹⁴ bicarbonates. Rates of translocation averaging 37 cm/hr in the laboratory were observed. Samples from the epidermis, cortex, and medulla of the stipes of plants with blades exposed to tracer showed that the radioactivity in organic compounds was confined to medulla where sieve filaments occurred. Girdle preparations of blades, interrupting the mucilage ducts and leaving the blade medulla intact, allowed translocation to take place. These data indicate that conduction of photosynthate takes place in the medulla. Similarities between the anatomy of algal sieve filaments and angiosperm sieve tubes, coupled with the continuity of the sieve filaments from blade medulla to stipe medulla suggested indirectly that the sieve filaments were conducting elements. Further support of this hypothesis was provided from collections of radioactive exudate from cells in the medulla of the lower stipe that were continuous with the sieve filaments. Tracer applied to the blades was partially recovered as organic material in a clear fluid that collected inside the pneumatocyst. Continued accumulation of radioactivity in this fluid was dependent on living blades; fluid with low specific activity that did not increase during the experiment accumulated slowly if blades were killed with ethanol after an exposure to tracer. It is possible that the system that produced the stipe fluid was part of (or a side effect of) the system responsible for maintaining volume in the conducting system. It may also provide an alternate route (other than the sieve filaments) for delivery of photosynthates to the base of the plant. Carbon-14 applied to blade tips as bicarbonate was recovered in part as radioactive mannitol in the translocation stream.