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91.
通常用于DNA克隆的载体,如质粒、λ噬菌体载体cos质粒(cosmid)等,其容量50kb,对于多数基因或某些小的基因簇,这个容量是足够的。但对于人类基因组研究和某些大基因的克隆,这些载体就有相当的局限性。例如人类第Ⅷ因子基因编码凝血因子,它的缺陷可... 相似文献
92.
对成骨不全先证者上溯5代372人进行家系调查,发现该家系共有28例成骨不全,其中已死亡10例(成人、儿童各5例),均非死于本病;现生存18例(成人12例、儿童6例)。该28例均身材矮小、身高显著低于同龄正常者;均有蓝色巩膜;符合常染色体显性遗传缺陷的结缔组织病。现存活18例中,耳聋、听力下降6例;骨折9例(22例次),对照文献中分型标准,本组28例与Ⅰ型、Ⅲ型的部分临床特征相符,是否系介于Ⅰ型、Ⅲ型之间的亚型,有待于进一步研究。
Abstract:A pedigree investigation was carried out on 372 relatives in five generations of a proband of osteogenesis imperfecta.The results showed that there were 28 patients in the family.10 of them died from other causes(5 adults and 5 children respectively).Other 18 cases are alive(12 adults and 6 children respectively).The height of the 28 cases were significantly lower than those of the same age.Furthermore,they all had blue scleras.Their clinical manifestations conformed to those of autosomal dominant hereditary connective tissue disease.Among the living 18 cases,6 suffered from deafness or hearing loss and 0 suffered from fracture(22 person-time altogether).According to the classification criteria in the literature,the clinical manifestations of the 28 cases conformed to those of type I and type III,It is necessary to study further whether they belonged to the subtype between type I and type III. 相似文献
93.
近年来微生物酶制剂有了较大的发展,生产工艺采用喷雾干燥法,或用浓缩发酵液添加防腐剂制成液体酶制剂,代替硫铵盐析,缩短生产周期,简化工艺,目前已开始推广。细菌淀粉酶酶液在贮存和待喷雾处理前,常出现严重失活现象,几天之内失活可达100%,并产生酸臭异味,不仅对酶制剂生产造成极大的损失,又污染工厂内外环境。为此,进行研究细菌淀粉酶酶液贮存中失活的原因及其防 相似文献
94.
用RAPD方法对平菇、香菇属间原生质体融合子的研究 总被引:9,自引:0,他引:9
刘国振 刘振岳 贾建航 刘丽娟 泰立芳 李小兵 朱衡 朱立煌LIU Guo-Zhen LIU Zhen-Yue JIA Jian-Hang LIU Li-Juan Tai Li-Fang LI Xiao-Bing ZHU Heng ZHU Li-Huang 《遗传》1995,17(5):37-40
RAPD是一种新的分子生物学技术。本实验用28个随机引物对平菇、香菇及其融合子进行PCR扩增, 在融合子谱带中,有64条与平菇相同(与平菇的相似指数SI=70.6%),14条与香菇相同(SI=33.6%),另外有26条谱带为双亲与融合子所共有。本实验结果说明融合子是双亲融合的产物,但在融合过程中,从双亲获得的遗传信息不等。本实验首次在食用真菌中获得了原生质体融合的分子生物学证据。我们认为,在食用菌研究中,RAPD将是一种有重要价值的分析方法。
Abstract:RAPD is a novel molecular biological technique.P.sapidus,L.edodes and their intergeneric fusants were tested by RAPD method using 28 randomly selected primers.In bands gained from fusants by amplification reaction,there were 64 bands with the same position as in P.sapidus (the similarity index (SI) was 70.6%),14 bands as in L.edodes.This results illustrated that fusants are true hybrid derived from protoplast fusion procedure,but the genetic information obtained from the two parents were not equal.Molecular biological evidence of protoplast fusion had obtained first time in edible mushroom by RAPD method in this experiment,we suggest that this technique is a valuable genetic marker for mushroom study. 相似文献
95.
一种非基因效应的遗传机制 总被引:1,自引:0,他引:1
一种非基因效应的遗传机制祝其昌(江苏省农业科学院经济作物研究所,南京210014)ANongenicHereditaryMechanismZhuQichang(InstituteofEconomicCrops,JiangsuAcademyofAgri... 相似文献
96.
水稻线粒体基因组与细胞质雄性不育研究进展 总被引:4,自引:0,他引:4
水稻线粒体基因组与细胞质雄性不育研究进展涂朱英国(武汉大学生命科学院,武汉430072)DevelopmentofRiceMitochondrialGenomeandCytoplasmMaleSterilityTuJunZhuYingguo(Col... 相似文献
97.
沈银柱 刘植义 黄占景 何聪芬 柏峰 马闻师 朱正歌 葛荣朝 许顺芝 岳聚兴 张中良SHEN Yin-zhu LIU Zhi-yi HUANG Zhan-jing HE Cong-fen BAI Feng MA Wen-shi ZHU Zheng-ge GE Rong-chao XU Shun-zhi YUE Ju-xing ZHANG Zhong-liang 《遗传》1999,21(5):41-545
在小麦叶枕距±2cm时, 喷施4种不同化学杂交剂(CHA)后, 分别取小孢子处于不同发育阶段的花药, 进行过氧化酶(POD)、淀粉酶(Amy)和酯酶(Est)等同工酶的分析。研究表明: 在小孢子母细胞减数分裂期, 处理2、3和4 三种CHA对POD的A1、A2; B2、B4和B5; C1、C2和C3同工酶带的活性均有明显的抑制作用; 处理5除去对A1和A2表现抑制外, 对其他酶带的活性均有增强作用。在单核早期, 处理2和3的A、B和C区POD 同工酶活性均明显低于对照; 处理4和5上述各区POD同工酶活性却明显高于对照。 在上述两个发育时期, 处理2对Amy1区酶活性有增强作用, 而处理3、4和5对该区酶活性却表现了专一性的抑制。各处理对Est同工酶A区和B 区的酶活性主要表现为抑制。实验结果表明, 不同的CHA均通过干扰花药的物质和能量代谢而导致雄性生理性不育。
Abstract:When the distance between wheat (T. aestivum ) flag leaf and it's adjucent leaf is about ± 2cm, four different kinds of CHA (Chemical Hybridizing Agents) were sprayed, then we took the anthers which were at different microspore's development stages to make POD、Amy and Est isoenzymes analysis. The study showed that: during the microsporocyte meiophase, treatmant 2、3 and 4, the three kinds of CHAs had evident inhibitation on the activity of POD's bands A1、A2; bands B2、B4 and B5; bands C1、C2and C3. CHA of treatment 5 had inhibitation on bands A1 and A2, but could promote the activity of the other POD bands. During the early uninucleate stage, the POD activity on area A、area B and area C with CHAs of treatment 2、3 was obviousely lower than the control. But in these areas POD activity with CHAs of treatment 4、5 was obviousely higher than the control. During the above two development stages, CHA of treatment 2 obviously strengthened the activity of Amy1area; on the other hand, CHAs of treatment 3、4 and 5 have the unique inhibitation in the same area. All the treatments mainly had inhibitant effects on the activities of Ests area A and area B. The study shows that all the different CHAs bring about male physiological sterility. Through disturbing the anther's metabolism of substances and energy. 相似文献
98.
99.
Cloning and expression analysis in mature individuals of two chicken type-Ⅱ GnRH (cGnRH-Ⅱ) genes in common carp (Cyprinus carpio) 总被引:1,自引:0,他引:1
LI Shuangfei HU Wei WANG Yaping & ZHU Zuoyan State Key Laboratory of Freshwater Ecology Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan China 《中国科学:生命科学英文版》2004,(4)
Gonadotropin-releasing hormone (GnRH), the pivotal signal molecular of hypothalamic-pituitary- gonad (HPG) axis, plays a crucial role in gonadal de-velopment and maintenance of reproduction function of vertebrates by stimulating the anterior pituitary re-leasing gonadotropin (GtH). Mammal GnRH (mGn- RH) was firstly identified from porcine and ovine in the 1970s[1,2], which was originally named luteinizing hormone releasing hormone, viz LHRH. To date, 16 GnRH variants have been characte… 相似文献
100.
WANG Lingling* MA Li * LENG Wenchuan YANG Jian ZHU Junping DONG Jie XUE Ying WAN Zhe LI Ruoyu & JIN Qi . State Key Laboratory For Molecular Virology Genetics Engineering Beijing China . Chinese National Human Genome Center Beijing Beijing China . Research Centre for Medical Mycology Beijing China 《中国科学:生命科学英文版》2004,47(5):389-395
Superficial fungi are the etiologic pathogens of various dermatophytoses, such as tinea capitis, tinea corporis, tinea inguinalis, tinea manus, tinea unguium and tinea pedis. These widespread infections affect up to 25% of the worlds population, a percentage that has continued to increase in recent years. T. rubrum is the most common superficial fungus, accounting for at least 60% of all infections of this type. T. rubrum can induce dermatophytoses in different parts of the hu-man skin, and ca… 相似文献