首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
A study of four species of Erysiphaceae (Uncinula salicis, Podosphaera leucotricha, Erysiphe cichoracearum, and Microsphaera diffusa) revealed that the binucleate stages of the ascocarp are initiated in a similar manner to those of Diporotheca rhizophila Gordon & Shaw. The “appendages” developing on immature ascocarps are considered to be receptive hyphae. Appendages characteristic of mature ascocarps are produced much later. Lysis of certain centrum cells occurs, and asci are initiated from some of the remaining binucleate centrum cells. Resorption of centrum cells by the asci is supported by this investigation, corroborating Björling's earlier studies on Erysiphe graminis.  相似文献   

2.
3.
4.
5.
6.
7.
8.
用分光光度法测定了4株郎比可假丝酵母(Candida lambica)间的DNA-DNA同源性,结果:2.1182与LP012的同源性为90.4%,表明它们是同种的;2.1182与DX22为77.5%,DX22与LP012为76.8%,表明它们虽是同种,但产生了一些分化:LP006与LP012为63.2%,表明它们之间产生了较大的分化,接近种的范围,仍可认为是同种的。  相似文献   

9.
10.
11.
A STUDY OF THE INNERVATION OF THE TAENIA COLI   总被引:11,自引:2,他引:9       下载免费PDF全文
An electrophysiological and anatomical study of the guinea pig taenia coli is reported. Changing the membrane potential of single cells cannot modulate the rate of firing action potentials but does reveal electrical coupling between the cells during propagation. The amplitude of the junction potentials which occur during transmission from inhibitory nerves is unaffected in many cells during alteration of the membrane potential, indicating electrical coupling during transmission. The taenia coli is shown to consist of smooth muscle bundles which anastomose. There are tight junctions between the cells in the bundles, and these probably provide the pathway for the electrical coupling. The smooth muscle cells towards the serosal surface of the taenia coli are shown electrophysiologically to have an extensive intramural inhibitory innervation, but a sparse sympathetic inhibitory and cholinergic excitatory innervation. These results are in accordance with the distribution of these nerves as determined histochemically. As single axons are only rarely observed in the taenia coli, it is suggested that the only muscle cells which undergo permeability changes during transmission are those adjacent to varicosities in the nerve bundles. The remaining muscle cells then undergo potential changes during transmission because of electrical coupling through the tight junctions.  相似文献   

12.
13.
14.
本文对山东枣庄市916人足放射片进行了足籽骨的观察与测量。发现每足有1-7个籽骨,其中二个者占77.8%,三个者占16.9%;籽骨位于跖骨头下方者占94.5%,位于趾间关节下方者占5.5%;各跖骨头籽骨出现率:Ⅰ占99.9%、Ⅱ占 2.2%、Ⅲ占0.3%、Ⅳ占0.5%、Ⅴ占6.4%;(足母)趾趾间关节籽骨占12.6%;二分及三分籽骨出现率占3.9%,明显低于欧美人。此外,本文认为籽骨是在先天籽骨原基基础上,加以后天运动的影响而形成。  相似文献   

15.
16.
17.
18.
19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号