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.
《BMJ (Clinical research ed.)》1948,1(4556):841-842
  相似文献   

2.
3.
4.
The development of the electron microscope in the advanced form we know today is the result of a loosely organized but effective world-wide scientific and technological collaboration, that readily transcends national and cultural barriers. The birth of the subject was undoubtedly in Berlin but the United Kingdom has played a prominent part, sometimes in an accidental way, at critical periods in this development both at the scientific and manufacturing level. In 1927, for example, G.P. Thompson established experimentally the wave nature of the electron and its scattering and diffraction by thin foils. This followed his invention of the electron diffraction camera at a time when De Broglie's postulates on the wave of nature of the electron were not enjoying much support, even in his native France. C.W. Oatley in Cambridge University was successful in introducing the first commercial scanning electron microscope (SEM) where several commercial firms had previously failed. D. Gabor invented electron holography in a moment of boredom while watching a tennis match. The U.K. has also played a key role in fostering international collaboration by means of conferences and exchange visits between electron microscopists. The present paper concentrates on some of the critical developments that took place in the U.K. in the commercial development of transmission electron microscopy, in scanning electron microscopy and more recently in high resolution electron microscopy. These developments are placed as far as possible in a world-wide context.  相似文献   

5.
6.
7.
8.
9.
10.
This is a wide-ranging review of muscle proprioceptors, intended primarily for the nonspecialist. It emphasizes how much more they are concerned with, than just the production of the knee jerk; it concentrates on principle rather than documenting detail and cites selectively. The main topics covered are the effect of deafferentation, position sense, the proprioceptors themselves, the control of the muscle spindle by the CNS, and spinal and long-latency "stretch" reflexes. The emphasis is on human work. The knee jerk itself is seen as a "physiological artefact," resulting from a mode of stimulation that does not occur in life, with the normal function of its underlying circuitry still under debate.  相似文献   

11.
12.
13.
14.
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