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61.
Xuchen Zhang Guoxiang Cheng Jianquan Chen Yong Cheng Yingrun Wei Wulan Yao Shaofu Xu Weide Lao 《科学通报(英文版)》2000,45(3):226-229
The present work has generated transgenic mice with a hybrid gene construct consisting of genomic sequences encodinghuman erythropoietin (hEPO) and governed by regulatory sequences of mousewhey acidic protein (mWAP). The construct proved effective by transient expression in lactating animal. After introducing hybrid gene construct into
single-cell embryo via pronuclear microinjection, surviving embryo are reimplanted into pseudopregnant foster mother mouse.
58 mice of 86 generation zero mice obtained were identified to be positive by PCR-Southern blot and genomic DNA Southern blot
methods. The integration rate is 67%.hEPO was expressed in the milk of 16 mice of 39 mice measured byhEPO ELISA kit The expression level gets over 15 μg/mL. 相似文献
62.
棉花腺体形成相关的miRNA差异表达研究 总被引:1,自引:1,他引:0
植物miRNAs在基因表达、生长、发育等方面有十分重要的作用.本实验以棉花显性无腺体近等基因系为材料,利用miRNA基因芯片杂交技术,分析与腺体形成相关的miRNA的差异表达.结果表明,棉花腺体形成期共有30个miRNA有差异表达,其中表达上调的miRNA有24个,分别属于miR156,miR157,miR166和miR390家族.表达下调的miRNA有6个,分别属于miR149,miR169,miR289,miR705,miR1224和miR1227家族.miRNA家族作用的靶基因分析发现主要分布在发育 相似文献
63.
64.
《Journal of Natural History》2012,46(1-2):35-58
The dorsal abdominal scent glands of nymphs in Lygaeoidea are diverse. Some related characters, such as number and distribution of dorsal abdominal scent gland openings (DSOs), and shapes of dark plates surrounding DSOs have been commonly used in taxonomic and/or phylogenetic studies of Lygaeoidea. However, comparative studies of the cuticular fine structures surrounding the DSOs in lygaeoid (and other Heteroptera) nymphs are few. We examined the cuticular fine structures surrounding DSOs of fifth‐instar nymphs of 25 species in seven families of Lygaeoidea with scanning electron microscopy. The results showed that the structures surrounding DSOs, such as distribution pattern of cell network, type of network, type of non‐latticed area, pattern of channels for glandular secretion, are complicated and diverse at the family level, indicating that they are valuable in taxonomic and phylogenetic analyses. 相似文献
65.
《Journal of Natural History》2012,46(2):331-348
Summary The larval development of Argulus coregoni from the first to the ninth stage was studied, with special reference to the morphological changes of the appendages and some other parts of the body. A newly hatched larva is a copepodid-form measuring 0·6–0·7 mm long and approaches the shape of the adult after moulting into the second stage (0·7–0·9 mm). Throughout the larval stages, the first maxilla shows the most remarkable modification. The larvae of the first to the fifth stage are equipped with two strong, curved claws, which act as a clasping organ, at the terminal segment of the first maxilla. The basal segment expands considerably at the third stage (0·9–1·1 mm) prior to forming a sucker at the sixth stage (1·7–2·2 mm). The claws start to degenerate at the fifth stage (1·4–1·8 mm), but are still recognizable as a rudiment after the seventh stage (2·2–2·6 mm). The other distinct morphological changes that occurred are: (1) bifurcation of the anterior part of the dorsal ridges on the carapace, (2) development of the male accessory copulatory organ at the basal segments of the second to the fourth legs, (3) number of posteriorly directed minute spines on the ventral surface of the carapace, (4) number of elements in the supporting ribs of the suckers, (5) number of spines found at the first segment of the second maxilla, and (6) number of setae on the four pairs of thoracic legs. The larval forms of A. coregoni younger than the fourth stage (1·1–1·4 mm) are indistinguishable from those of A. japonicus and A. foliaceus. 相似文献
66.
Ecdysteroids in vitro promote differentiation in the accessory glands of male mealworm beetles 总被引:2,自引:0,他引:2
Summary Physiological peak doses of 20-hydroxyecdysone were added to organ cultures of young pupal accessory glands of maleTenebrio molitor. During subsequent culture in vitro or in vivo, the glands accumulated adult-specific antigens. Control organ cultures showed no such antigen accumulation. In this system, ecdysteroid controls not only cell cycles but also differentiation.21 October 1986This research was supported in part by a National Institutes of Health Research Service Award F32 AM7515 (KAG) and NIH grants GM26140 and AI15662 (GMH). We thank Toshinobu Yaginuma for help in developing the transplantation technique. 相似文献
67.
近红外乳腺扫描3000例分析 总被引:2,自引:0,他引:2
张少华 《海南大学学报(自然科学版)》2002,20(2):163-164,167
为评价近红外乳腺扫描诊断乳腺癌的意义 ,笔者选择了 30 0 0例乳腺患者应用近红外扫描诊断与病理诊断进行对照分析 .结果表明 :近红外扫描诊断乳腺癌的正确率为 95 .6 % .提示 :近红外乳腺扫描对良恶性肿物的鉴别诊断是一种行之有效的方法 ,具有安全、可靠、无损伤等特点 . 相似文献
68.
应用大体解剖学和组织学方法探讨中国西北、华北地区特有动物--双峰驼眼球及其附属器官的解剖组织学特点,为特有资源的保护和开发研究提供一定的理论依据.结果表明:双峰驼具有2~5行睫毛和双层眼睑.骨性眼眶夹角约为95~105°.眼肌有四条直肌、两条斜肌、一条上提睑肌和漏斗肌.双峰驼泪腺呈不规则三角形,角膜高度角质化,视网膜为典型的十层结构.双峰驼眼的主要结构与其他脊椎动物类似,在形态学特点和组织学结构方面与其生长的荒漠、半荒漠环境相适应. 相似文献
69.
用石墨炉原子吸收光谱法测定了213名健康妇女,36例乳腺良性瘤和38例乳腺恶性瘤手术前后血清中Zn,Fe,Cu,Mn,Ph,Cd,Cr,Ni和Mo九种微量元素的含量.结果发现三组血清中有五种元素有显著性差异,其中血清Zn,Cu,Ni和Fe的含量乳癌患者明显高于对照组,血清Mo则乳癌患者低于对照组,而且血清Zn,Cu,Ni随病情发展而升高,血清Mo则相反;乳癌患者血清Cu/Zn值(1.48)高于健康组(1.30). 相似文献
70.
外源基因在转基因动物乳腺中的特异性表达研究 总被引:2,自引:0,他引:2
动物基因工程研究最大的突破就是转基因动物研究的进展,自八十年代初第一批转基因小鼠问世以来,转基因动物的研究已从方法学研究步入了应用性研究阶段,转基因动物除作为研究工具广泛应用于发育生物学、免疫学、遗传学以及医学等生命科学领域外,外源基因在转基因动物的特异性表达,尤其是在乳腺的表达,又可将转基因用作生物反应器进行了生物活性蛋白的生产而于商业生产,在转基因动物乳腺的特异性表达研究中,寻找乳蛋白基因调控 相似文献