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C-9-1, a monoclonal IgM antibody raised against human null cell acute lymphocytic leukemia cells reacted with restricted regions of embryonic and adult tissues of the mouse. The antigen positive sites in the embryos included embryonic ectoderm, visceral endoderm, trophoblastic cells invading the maternal decidua of 5∼7-day embryos, primordial germ cells of 10∼12-day embryos, epithelium of nasal chamber, the bronchus, Mullerian duct, epididymis and bladder of 12∼17-day embryos. In the adult mice, C-9-1 antigen was detected in renal tubules, a part of stomach, bladder, endometrium and epididymal sperm. Embryonal carcinoma cells, but not endodermal cells of teratocarcinoma expressed the antigen. Thus, C-9-1 antigen showed distribution similar to SSEA-1. However, C-9-1 antigen was not detected in preimplantation embryos, nor in oviduct, both of which are positive for SSEA-1.  相似文献   
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The Hill reaction of chloroplasts was inhibited by washing themwith 0.8 M Tris buffer. This inhibition was further promotedby adding ferricyanide in the washing medium. When a reducingreagent, such as the 2,6-dichlorophenol indophenol (DCPIP)-ascorbatesystem or the hydroquinone (HQJ-ascorbate system, had been addedto the Tris buffer, Hill reaction activity was unaffected. Hill reaction activity of Tris-washed chloroplasts recoveredup to 70% of the initial level by re-washing the chloroplastswith a preparation medium containing theabove reducing reagents. Photobleaching of carotenoid and chlorophyll is characteristicof Tris-washed chloroplasts. However, reactivated chloroplastsshowed no photobleaching as in the case with intact chloroplasts. (Received April 20, 1970; )  相似文献   
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Sokawa et al. suggest that rel- strains of Escherichia coli possess abnormal protein synthesizing machinery, which cannot carry out normal protein synthesis when the supply of amino-acids is limited.  相似文献   
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Two new phenomena were observed during macronuclear development in E. patella. During the formation of giant chromosomes, the number of chromosomes decreased while individual chromosomes gradually became longer and thicker. Immediately before macronuclear elongation, ring-like anlagen appeared, which did not contain chromatin at their centers. The course of macronuclear development in Euplotes is reconsidered in light of these findings.  相似文献   
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ABSTRACT. Microsporidian spores were developed from cells which were grown in vitro from a human liver lesion which was due to larval Echinococcus multilocularis . The microsporidian spores developed in the same fashion as an Encephalitozoon cuniculi . The Encephalitozoon -like spores were completely separated on Percoll gradients. The separated spores contained DNA capable of amplification by two different primer sets designed for the polymerase chain reaction (PCR) of E. multilocularis DNA. However, the cell DNA from which microsporidium developed was thoroughly insensitive to the PCR using the E. multilocularis primer sets. The results strongly suggested that Encephalitozoon should be taken into consideration, when DNA isolated from larval E. multilocularis is analyzed.  相似文献   
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Experimental studies on parasitization by Apanteles glomeratus.   总被引:1,自引:0,他引:1  
ABSTRACT. The host-finding sequence of Apanteles glomeratus females and the factors involved in it were analysed. A female wasp is attracted by the leaf odour of the food plant of the host ( Pieris rapae crucivord ). She then walks slowly with the tips of her antennae rubbing the leaf surface. When she comes across damage produced by the host's feeding, her antennae are raised and she turns towards the damage. She often then erects her wings and/or bends her abdomen forward in response to a chemical produced from the leaf by the host's saliva. Long-lasting searching elicited by this odour normally leads to an encounter with a host caterpillar, whereupon odour from the host itself releases opposition. Host saliva, faeces and silk are also involved in these responses, but the response to fresh leaf damage has the most specific function in the overall strategy of host-finding.  相似文献   
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