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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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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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When rat liver mitochondria labeled with [59Fe]heme were incubated with microsomes in the presence of cytosol, about 16 % of the heme in mitochondria was transported to microsomes during a 1 hr-incubation period. In the absence of cytosol, little heme was transported. DEAE-Sephadex column chromatography of the cytosol partially purified by pH 5.1 treatment and ammonium sulfate precipitation (45–65%) revealed that there were at least two proteins with a releasing activity from mitochondria via heme transport.  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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The ovarian cycle and conception of sika deer were studied to reveal factors responsible for delayed conception. Concentration of progesterone in feces from 12 female Hokkaido sika deer (Cervus nippon yesoensis Heude, 1884) was measured during the mating season in 2000. The cyclic pattern of fecal progesterone synchronized with estrous symptoms, which could hence be interpreted as indicating ovarian cycle. All observed females ovulated by 14 October. However, during the early mating season, females did not permit copulation at ovulation, and the length of luteal phase following ovulation without estrus was 9.8±4.6 days (5–24days). Most females conceived at the first copulation, which were confirmed by progesterone profiles that was sustained at a high level after the copulation. This indicates the presence of a functional corpus luteum, a state of pregnancy. Thus, some females had repeated ovulation without copulation several times, creating a 3–4week variation in the timing of conception. But some females conceived very late in the mating season after the repetition of ovulation and copulation.  相似文献   
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Production of transgenic miniature pigs by pronuclear microinjection   总被引:2,自引:0,他引:2  
Miniature pig is an attractive animal for a wide range of research fields, such as medicine and pharmacology, because of its small size, the possibility of breeding it under minimum environmental controls and the physiology that is potentially similar to that of human. Although transgenic technology is useful for the analysis of gene function and for the development of model animals for various diseases, there have not yet been any reports on producing transgenic miniature pig. This study is the first successful report concerning the production of transgenic miniature pig by pronuclear microinjection. The huntingtin gene cloned from miniature pig, which is a homologue of candidate gene for Huntington's disease, connected with rat neuron-specific enolase promoter region, was injected into a pronucleus of fertilized eggs with micromanipulator. The eggs were transferred into the oviduct of recipient miniature pigs, whose estrus cycles were previously synchronized with a progesterone analogue. A total of 402 injected eggs from 171 donors were transferred to 23 synchronized recipients. Sixteen of them maintained pregnancy and delivered 65 young, and one resulted in abortion. Five of the 68 offspring (three of which were aborted) were determined to have transgene by PCR and Southern analysis. The overall rate of transgenic production was 1.24% (transgenic/injected eggs). This study provides the first success and useful information regarding production of transgenic miniature pig for biomedical research.  相似文献   
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