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71.
72.
五种野生稻叶绿体DNA多态性研究 总被引:7,自引:0,他引:7
对野生稻 5个种的18个材料的叶绿体DNA(cpDNA)进行了EcoRI的RFLP分析。
结果显示,共有10种酶切模式,不同种野生稻的cpDNA的RFLP类型都不同,而且在其中一些
种内也有变化,尤以O.rufipogon的种内多态性最为显著,并主要与地理来源有关。本研究还在O.punctata的材料中发现一种以往的分析都不曾描述过的多态性模式。通过对结果的分析,探讨了不同种类野生稻的叶绿体基因组之间以及它们与核基因组之间的进化关系。
Abstract:The polymorphisms of chloroplast DNA from 18 materials of 5 wild rice species were investigated using RFLP analysis.10 restriction patterns were obtained from the analysis of these materials.Different species had different of its RFLP patterns chloroplast DNA,and the polymorphisms existed even with species,especially in O.rufipogon varieties of different geographical origins.In O.punctata a new type of rice chloroplast DNA restriction pattern was discovered which had not been reported before.According to the results obtained,the evolutionary relationships among chlorplast genomes,and between chloroplast and nuclear genomes in different wild rice are discussed. 相似文献
73.
通过使用 PARP酶的抑制剂研究了降低PARP酶的活性对外源基因转染效率及整合作用的影响, 结果表明,转染的外源基因的吸收及瞬时表达不依赖于PARP酶的活性,而外源基因的整合作用与PARP酶的活性有关。
Abstract:In this study,the effect of lowering PARP activity on the transfection of cultured cells with foreigh genes was evaluated.The results indicated that PARP enzyme involved in the stable integration of foreign genes into the host genome.However,inhibition of PARP activity exhibited no effect on both the uptake into the cells and the expression of the forging genes. 相似文献
74.
WU YU ZHANG YING WAN DAO GUO LI YAN TANG WEI ZHOU Institute of Immunology PLA The Third Medical University Chongqing China Medical Center General Hospital of Weifang Weifang China 《Cell research》2001,(3)
INTRODUCTIONHepatitis B virus (HBV) infection is the mostcommon viral infection in humans especially inChina and East Asia. At present, the most effi-cient method to control the disease is vaccinationof new-borns. Both blood derived vaccine and re-combinant vaccine are hepatitis B surface alltigen(HBsAg)-based and useful in the prevention of thedisease[1-3]. HBsAg could evoke protective humoralimmune response in vivo, but the immune memoryonly last for 5 years or so[3, 4]. How to des… 相似文献
75.
Alam Md. Asraful WAN Chun ZHANG Xiao-yue GUO Suo-lian ZHAO Xin-qing BAI Feng-wu 《微生物学杂志》2014,(6):49-54
微藻是可广泛用于健康食品及水产养殖的饵料,同时,微藻细胞内积累的油脂可作为可再生生物燃料,因此微藻的生长和代谢受到广泛关注。温度和pH对微藻的生物量积累有很大影响,考察不同温度和pH条件下微藻细胞的生长有助于寻找最佳的条件进行微藻的培养。自絮凝小球藻JSC-7(Chlorella vulgaris JSC-7)可实现自沉降采收,有利于降低微藻生产成本,优化其生长条件对更好地利用该微藻具有重要意义。考察了温度(22∽40℃)及pH(6.0∽10.0)对其细胞生长、叶绿素含量和油脂产量的影响。在所选取的温度及pH范围内,JSC-7细胞均可生长,显示该藻种可以适应广泛的温度和pH条件。适合细胞生长的温度依次为31℃〉28℃〉35℃〉25℃,pH依次为7.0〉8.0〉6.0。pH 8.0时生物量和油脂的积累量最多,说明该藻株在弱碱条件下更适合生长和产油。当温度为31℃、pH为7.0时,可获得最高的生长量(OD690=0.941)、叶绿素含量(19 mg/L)及油脂产量(39.07%/克干重)。 相似文献
76.
红花玉兰种质资源遗传多样性初探 总被引:3,自引:0,他引:3
采用AFLP分子标记对目前仅发现在湖北五峰狭域分布的红花玉兰种质资源的遗传多样性进行了研究.用10对引物对6个居群的43个个体进行了选择性扩增,共检测到623个有效位点,其中多态位点595个.结果表明:在物种水平上,红花玉兰的遗传多样性水平很高,多态位点百分率达95.51%,Nei s基因多样度(HT)为0.211 0±0.028 6;红花玉兰的遗传变异主要存在于居群内,居群间的遗传分化较小.AMOVA分析表明总变异的93.37%存在于居群内,居群间的变异只占总变异的6.63%.Nei s遗传分化系数(GST)为0.191 9,居群间基因流(Nm)2.105 5.鉴于红花玉兰总体遗传多样性水平很高,而居群数目及居群内个体数量均很少,应该对红花玉兰各居群的所有个体实施及时的就地保护,并对其生境进行保护;并在原产地营建基因保存林,营建时应加大各居群内的取样数量,使得红花玉兰较高的遗传多样性得到保存;同时积极开展异地引种栽培,使红花玉兰在观赏应用中得到切实的保护. 相似文献
77.
HIV Vaccine-Challenges and Opportunities 总被引:1,自引:0,他引:1
Xin MA Cai-jun SUN Feng LI Ling CHEN 《Virologica Sinica》2007,22(6):486-492
The need for an efficacious HIV/AIDS vaccine remains the highest priority of the world HIV/AIDS agenda. The generation of an efficacious HIV/AIDS vaccine proves an enormous scientific challenge. This article reviews the neutralizing antibody problem,elusive immune protection,im-munogen design,pre-existing anti-vector immunity and design of phase 3 vaccine trials and the challenges and opportunities in development of HIV/AIDS vaccine are discussed. 相似文献
78.
Xue-mei ZHANG Yan-chun CHE Jing-jing WANG Long-ding LIU Ming-xue XIE Qi-han LI 《Virologica Sinica》2007,22(1):41-45
The genome of a new SV40 strain (SV-IMB) isolated from a rhesus monkey was completely sequenced and compared with other isolates. The results showed that the whole genome contains 5246bp, and the average identity of SV-IMB was 98.1% as compared to other SV40 isolates. Its regulatory region is composed of a complete enhancer and a defective enhancer. Amino acid changes occurred to some extent in both the large T antigen (T-Ag) and VP1 region. The findings demonstrate that the SV-IMB is a new SV40 isolate. 相似文献
79.
Wen-rong YAO Guo-qiang PAN Cheng-long XIONG Qian-fu ZHOU Qi-you XIAO Ming-hui LI Yong-zhen ZHANG 《Virologica Sinica》2007,22(4):307-315
Saliva and blood were collected from two patients who had not received post exposure prophylaxis in the cities of Wenzhou and Xinning respectively. Both patients were confirmed as positive for rabies by detection of rabies virus specific nucleoprotein antibodies in the sera by Western Blot. However, rabies virus specific RNA was only identified in the saliva collected from the patient in Wenzhou. Furthermore, the isolate Zhejiang Wz0 (H) was obtained by inoculating one-day-old suckling mice. Both nucleoprotein (N) and glycoprotein (G) genes from the isolate were amplified by RT-PCR and sequenced. Phylogenetic analysis indicated that the isolate belonged to classic rabies virus, and shared a higher homology with the street viruses from dogs in the main endemic areas in China and the street virus from dogs in Indonesia than with other known strains. Further comparison of the deduced amino acid sequences between the isolate and the vaccine strains used in China showed that the virus had a higher level of homology with the vaccine strain CTN than with the other vaccine strains (3aG, PV, PM and ERA). In particular, amino acid residues substitutions located in antigenic site Ⅲ in the G protein, which could react with the neutralizing antibodies, were observed. These results suggested that the virus belonged to the classic rabies virus, and both N and G genes diverged from the current vaccine strains used in China at either the nucleotide or the amino acid level. 相似文献
80.
The study of mutualistic plant and animal networks is an emerging field of ecological research. We reviewed progress in this field over the past 30 years. While earlier studies mostly focused on network structure, stability, and biodiversity maintenance, recent studies have investigated the conservation implications of mutualistic networks, specifically the influence of invasive species and how networks respond to habitat loss. Current research has also focused on evolutionary questions including phylogenetic signal in networks, impact of networks on the coevolution of interacting partners, and network influences on the evolution of interacting species. We outline some directions for future research, particularly the evolution of specialization in mutualistic networks, and provide concrete recommendations for environmental managers. 相似文献