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31.
ＩＮＴＲＯＤＵＣＴＩＯＮＡｍｐｈｉｏｘｕｓｏｒｌａｎｃｅｌｅｔ,ａｃｅｐｈａｌｏｃｈｏｒｄａｔｅ,ｈａｓｌｏｎｇｂｅｅｎｒｅｇａｒｄｅｄａｓｔｈｅｌｉｖｉｎｇｉｎｖｅｒｔｅｂｒａｔｅｍｏｓｔｒｅｓｅｍｂｌｉｎｇｔｈｅａｒｃｈｅｔｙｐｅｏｆｖｅｒｔｅｂｒａｔｅｓ.Ｉｔｈａｓｂｅｅｎｗｉｄｅｌｙｋｎｏｗｎａｓｏｎｅｏｆｔｈｅｍｏｓｔｉｍｐｏｒｔａｎｔｓｐｅｃｉｅｓｉｎｔｈｅｚｏｏｌｏｇｉｃａｌｗｏｒｌｄ,ａｎｄｈａｓｂｅｅｎｅｍｂｒｙｏｌｏｇｉｃａｌｌｙｓｔｕｄｉｅｄｆｏｒｏｖｅｒ130ｙｅａｒｓ(Ｚｈａｎ… 相似文献
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LOCALIZATION OF A PUTATIVE EPIBOLY-DETERMINING FACTOR IN OOCYTES OF THE GOLDFISH (CARASSIUS AURATUS)
It is unknown whether cytoplasmic determinants in goldfish eggs are asymmetrically localized beforematuration. In this study fully grown goldfish oocytes with infact germinal vesicles (GVs) were ligated withbaby hair loops along desired planes into two parts, mature in vitro, and inseminated. Embryos developedfrom the animal halves with GV of oocytes ligated along the equator un unable to undergoepiboly, while those developed from the GV-containing parts of oocytes ligated along the animal-vegetal axiswere able to. Also, embryos developed from the animal halves obtained from fertilized eggs could undergo epiboly. From there results, it was postulated that the goldfish's premature oocyte possessed a putativefactor in the vegetal hemisphere which was responsible for epiboly of the embryonic cells. 相似文献
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蛋白质三级拓扑结构对热稳定性贡献的初步探讨 总被引：1，自引：0，他引：1
搜集来自数据库和文献的127个已测定熔解温度和PDB结构的热稳定蛋白,计算了每个蛋白PDB结构的9种拓扑参数,并对各个参数与其自身熔解温度做了线性相关性分析。现有数据结果表明只有CC这个参数与Tm的相关性系数达到了0.33。CC参数表征蛋白结构作为天然接触的网络来处理时的簇系数,因此这一关系表明组成蛋白的基团接触的越紧密,蛋白的热稳定性就越高,这与之前的研究结论相一致。而其它的参数没有发现与Tm有显著的关系。作者从拓扑结构这个方面进行研究为蛋白质的热适应机理研究提供了新的思路。 相似文献
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毛蚶血清凝集素的凝集活性 总被引：2，自引：1，他引：2
以毛蚶为实验材料,对其血清中的凝集素进行研究.毛蚶血清凝集素对人的A,B,O血型红细胞、鸡和小鼠的红细胞均有凝集作用,凝集效价分别为256,256,8,16,64,同时它还能对白色念珠菌、啤酒酵母、溶藻胶弧菌等微生物具有凝集作用.毛蚶血清凝集素具有一定的pH值稳定性和热稳定性.在选用的12种单糖和寡糖中,L-鼠李糖、L-树胶醛糖、麦芽糖、D-半乳糖、蔗糖对毛蚶血清的凝集活性有明显的抑制作用.用弧菌对毛蚶进行免疫刺激时,其血清对鸡红细胞的凝集效价明显增加. 相似文献
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鱼类免疫系统的早期发生 总被引：2，自引：0，他引：2
鱼类养殖业的发展极大促进了近10年来对鱼类早期免疫系统发生的研究,并取得一些新进展。本文就母体免疫因子向卵子转移和早期胚胎免疫、胚胎血细胞发生、淋巴器官和淋巴细胞发生以及体液免疫的发育4个方面,对鱼类早期免疫系统的发育做简要评述。 相似文献
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将经直接消化的斑马鱼头肾细胞或经短暂培养的尾鳍细胞核移植到同种成熟具核卵子中 ,移核卵可发育到原肠晚期 ;将移核卵发育成的囊胚细胞核作供体进行第 2次核移植 ,受体卵可发育到尾芽期或肌肉感应期。流式细胞仪测定 DNA含量表明 ,受体卵发育形成的囊胚细胞 DNA含量与正常囊胚细胞 DNA含量相同 ,由此可知 ,移核卵中的雌原核没有参与移核胚胎的发育。 相似文献
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The FG-9307 cell line derived from the gill of flounder Paralichthys olivaceus was used in the present study to determine the acute cytotoxic effects of the organophosphorous pesticide, profenofos. It was found that the cell growth rate was markedly reduced by profenofos at the concentrations of 2.5, 5 and 7.5 mg/L tested; and that the fine structures of the cells were also altered by profenofos, as evidenced by dilation of nuclear membranes and mitochondria cristae, and presence of enlarged lysoscrneswith engulfed organelles and numerous vacuoles in the cytoplama. Probably, mitochondria, the cell ener-gy-generating sites, are the most prcrninent sites of profenofos cytotoxity in the cells. This seems to be the first report of the use of marine fish cell line for evaluation of the acute in vitro cytotoxicity of organophos-phorus pesticide. 相似文献
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ＩＮＴＲＯＤＵＣＴＩＯＮＰｏｌｌｕｔｉｏｎｏｆｍａｒｉｎｅｅｃｏｓｙｓｔｅｍｐｏｓｅｓａｓｅｒｉｏｕｓｔｈｒｅａｔｔｏｍａｒｉｎｅｏｒｇａｎｉｓｍｓａｎｄｕｌｔｉｍａｔｅｌｙｔｈｅｅｎｔｉｒｅｅｃｏｓｙｓｔｅｍ.Ｉｎｒｅｃｅｎｔｙｅａｒｓ,ｏｒｇａｎｏｐｈｏｓｐｈｏｒｏｕｓ(ＯＰ)ｐｅｓｔｉｃｉｄｅｓｈａｖｅｌａｒｇｅｌｙｒｅｐｌａｃｅｄｏｒｇａｎｏｃｈｌｏｒｉｎｅｐｅｓｔｉｃｉｄｅｓｂｅｃａｕｓｅｏｆｔｈｅｉｒｒａｐｉｄｂｒｅａｋｄｏｗｎｉｎｗａｔｅｒａｎｄｔｈｅｉｒｌｏｗｅｎｖｉｒｏｎｍｅｎｔａ… 相似文献