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1.
Univalent antibody (Fab fragments) against sperm-binding factor inhibits the fertilization of eggs species-specifically. The sperm-binding factor was partially purified from unfertilized eggs of the sea urchin Anthocidaris crassispina by monitoring its neutralizing effect on fertilization inhibiting Fab fragments. It formed two species-specific precipitin lines by the double-immunodiffusion test and gave three main bands of protein with apparent molecular weights of 80,000, 87,000 and 225,000, on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Carbohydrate was detected in the first and third of these protein bands.  相似文献   
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Two multiplex PCR amplifications were performed to analyse six microsatellite loci of Schlegel's black rockfish, Sebastes schlegeli, an important commercial fish in the northern part of Japan and an important species for the stock enhancement program in this area. We analysed 67 wild samples from Yamada Bay, Iwate Prefecture, Japan. The observed genotype frequencies agreed with the Hardy–Weinberg expectations at all loci, and the observed heterozygosities ranged from 0.072 to 0.897.  相似文献   
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An ATPase was extracted and purified from castor bean endospermmitochondria. The enzyme is stable at 60°C only in the presenceof ATP in the incubation medium. It is less stable at 0°Cthan at 30°C but is stabilized by ammonium sulfate or glycerol.Activity is dependent on the presence of Mg++, and in the presenceof Mg++ is enhanced by 2,4-dinitrophenol, but is not inhibitedby oligomycin. The enzyme hydrolyzes ITP in addition to ATP,but ITPase activity is hardly enhanced by 2,4-dinitrophenol.This preparation has many properties in common with the ATPase(coupling factor 1) from beef heart mitochondria. (Received November 8, 1969; )  相似文献   
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15N-labeled nicotine was degraded in tobacco plant when it wasinjected into leaf at the vegetative stage. Topping of inflorescencedepressed the degradation, and no degradation was found whennico tine was injected 10 days after the topping. These resultsmay partly explain the known fact that the content of nicotinein tobacco plant is low in their younger stages and increasesafter the topping. 15N-labeled nicotine supplied to leaf was transported to otherparts of the plant without degradation. (Received September 1, 1962; )  相似文献   
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Previous studies have demonstrated that experimental type 1 diabetes induced by streptozotocin causes alterations in the biochemical and functional properties of several receptor systems in the rat bladder. However, the exact mechanism involved in the pathophysiology of voiding dysfunction in type 2 diabetic patients is unknown. Because the GK rat is a widely accepted genetically determined rodent model for human type 2 diabetes, we investigated diabetes-induced changes in the bladder smooth muscle of the GK rats at several time points. Male GK rats and age-matched Wistar rats, as controls, were maintained for 4, 8, 16, and 32 weeks. Contractile responses to KCl, carbachol, ATP, and electrical field stimulation (EFS) were measured by using the isolated muscle bath techniques. Acetylcholine (ACh) release induced by EFS from bladder muscle strips was measured by using high-performance liquid chromatography coupled with a microdialysis procedure. Maximum contractile responses to carbachol and ATP, the release of ACh, and tissue sorbitol levels were similar in bladders from GK and control rats until 8 weeks of age. At 16 weeks of age, however, the contractile responses to carbachol and ATP, and tissue sorbitol levels were increased, and the EFS-induced ACh release was decreased in GK rats compared with controls. Although the maximum contractile responses to EFS were unchanged until 16 weeks of age, they were decreased in 32-week-old GK rats, compared with controls. Our data indicate the presence of age-related alterations in the biochemical and functional properties of the bladder in type 2 diabetic GK rats.  相似文献   
7.
A study was made of chages in the activities of enzymes relatedto the biosynthesis of aromatic compounds in etiolated mungbean seedlings during their growth. Shikimate: NADP oxidoreductaseactivity in the root-shoot axes increased rapidly to attainits highest activity the 4th day after sowing, and remainedat that level over the experimental period of 7 days. 5-Dehydroquinatehydro-lyase activity continuously increased for at least 7 days.In the cotyledons, a gradual decrease in the activities of theseenzymes occurred. Phenylalanine ammonia-lyase activity in root-shootaxes gradually increased showing a maximum on the 6th day. Thehighest specific activity, on a protein basis, of this enzymewas seen in the initial stage of growth. In the cotyledons,a rise in total activity appeared on the 2nd day. Tyrosine ammonia-lyaseactivity was very low as compared with phenylalanine ammonia-lyase.The enzyme activities of light-germinated seedlings were comparedto those of dark-germinated seedlings on the 7th day. Lighthad practically no significant effect on the appearance of shikimate:NADP oxidoreductase and 5-dehydroquinate hydro-lyase activities.On the other hand, a marked effect from the light on the riseof phenylalanine ammonia-lyase and tyrosine ammonia-lyase activitieswas found, especially in the epicotyl-plumules. The results are discussed with respect to the metabolism ofalicyclic acids such as shikimic acid in the developing mungbean seedlings. 1This work was partly supported by a grant-in-aid from the Ministryof Education.  相似文献   
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水稻穗颈维管束及穗部性状的QTL分析   总被引:15,自引:0,他引:15  
以籼稻 (OryzasativaL .ssp .indicaZYQ8)和粳稻 (O .sativassp .japonicaJX17)的杂交F1代花培加倍的DH群体为材料考察了该群体的穗颈节大小维管束数、一次枝梗数、每穗颖花数、穗颈节顶部直径和穗长 ,并用该群体构建的分子图谱进行数量性状座位 (QTL)分析。检测到控制大维管束的 3个QTL (qLVB_1、qLVB_6和qLVB_7)分别位于第 1、第 6和第 7染色体 ;控制小维管束的 2个QTL (qSVB_4和qSVB_6 )分别位于第 4和第 6染色体 ;控制一次枝梗的 4个QTL (qPRB_4a、qPRB_4b、qPRB_6和qPRB_7)分别位于第 4(2个 )、第 6和第 7染色体 ;每穗颖花数的 3个QTL (qSPN_4a、qSPN_4b和qSPN_6 )分别位于第 4(2个 )和第 6染色体上 ;穗颈节顶部直径的 5个QTL (qPTD_2、qPTD_5、qPTD_6、qPTD_8和qPTD_12 )分别位于第 2、第 5、第 6、第 8和第 12染色体 ;穗长的 3个QTL (qPL_4、qPL_6和qPL_8)分别位于第 4、第 6、第 8染色体上。其中qLVB_6、qSVB_6、qSPN_6、qPTD_6和qPL_6均位于第 6染色体的G12 2_G1314b之间 ;qPL_8和qPTD_8位于第 8染色体的GA40 8_BP12 7a之间 ;qPRB_4a和qSPN_4a位于第 4染色体的G177_CT2 0 6之间 ;qPL_4和qSPN_4b位于第 4染色体CT40 4_CT5 0 0之间 ;qSVB_4所在的区间与qPL_4、qSPN_4b和qPRB_4b所在的区间相邻。  相似文献   
10.
A strain of carrot cells (Daucus carota cv. Kintoki) grew exponentially in the presence of 2,4-dichlorophenoxyacetic acid (2,4-D, 1 mg/1) with a doubling time of about 2 days. When those cells were transferred to a medium lacking 2,4-D, they continued to grow at almost the same rate for about a week. When the cells were again transferred to the auxin-free medium, the rate of cell division gradually decreased. After the cell division had ceased, cells were returned to the ordinary 2,4-D medium. A burst of cell divisions occurred after about 2 days. Timing of DNA synthesis and of mitosis suggested that the cells had been arrested at G1 phase. In a medium containing indoleacetic acid instead of 2,4-D, the auxin was rapidly degraded and the culture was similarly synchronized as in the auxin-omitted medium.  相似文献   
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