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A preliminary electron microscope study of human neuromuscular junction is presented. The biopsy material was taken from the palmarus longus, and fixed routinely in osmium tetroxide and embedded in methacrylate. The structure of the motor endings and the relationship of the synaptic vesicles to the axolemmal membrane are described. The synaptic clefts are filled with an homogeneous material in continuity with the basement membrane covering the muscle fiber. The subneural apparatus is described, and special attention is paid to a vesicular component present in the sarcoplasm of the junctional area, which differs from synaptic vesicles and is presumed to be a derivate of the sarcoplasmic reticulum. 相似文献
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DE MAN JC 《Antonie van Leeuwenhoek》1957,23(1):87-96
Summary The amount of acid formed in grass silage was greater than could have been formed from the soluble sugars present, even when
only a lactic fermentation took place. This seemed to point to fermentation of cell wall substances by lactic acid bacteria.
Lactic acid fermentation in potato pulp always takes place with cell wall substances as substrates, as sugars are absent.
It was found that galactose, probably occurring as galactan, and also some pectic acid were fermented in potato pulp.
Some lactobacilli were isolated from potato pulp; streptobacteria which could ferment galactan but no pectic or galacturonic
acid, and betabacteria which could ferment galacturonic acid but no galactan or pectic acid.
A number of homofermentative lactobacilli were all found to belong to the speciesStreptobacterium casei. It was shown that a strain of this species could ferment galactan in potato pulp sterilised previously with ethylene oxide.
Part of this work was carried out at the Netherlands Institute for Dairy Research, Ede, Netherlands. 相似文献
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