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61.
62.
以淀粉珠为载体的亲和层析法分离纯化高温α淀粉酶张学忠,宋伦,王群,吴晓霞,唐锌进(吉林大学酶工程国家重点实验室,长春130023;南京师范大学生物系,南京210024)金凤燮等人从酒曲中筛选出高产热稳定α淀粉酶的菌株,命名为Bacillussp-JF... 相似文献
63.
汉防己甲素(汉甲)及克矽平(Polyvinylpyridine-N-Oxide,PVNO)是目前较为有效的抑制矽肺纤维化的药物。本文研究了其对胶原mRNA水平的影响.斑点杂交实验表明大鼠接尘60天和120天后α1(Ⅰ)及α1(Ⅲ)mRNA水平明显上升,经汉甲或克矽平治疗1个月或3个月后,胶原mRNA水平明显下降。原位杂交结果表明胶原mR-NA银颗粒与细胞性结节和增厚的肺泡壁的成纤维细胞分布重合。汉甲或克矽平治疗后银颗粒数下降。提示汉甲及克矽平对矽肺进程中的胶原基因表达增强有抑制作用。 相似文献
64.
An earlier experiment with the pink lady's slipper orchid demonstrated that plant leaf area was lowered only after successive years of increased fruit production. This result suggested that the cost of reproduction was small in relation to the energy budget of the plant. To test this idea, plants were subjected to experimental hand-pollination treatments to increase fruit set as well as leaf removal treatments to decrease the energy budget of plants. Changes in plant size in years 2 and 3 and, to some extent, rate of flowering, were determined by a combination of initial plant size, leaf removal treatments in year 1, fruit production in year 1, and damage from an unplanned fire in year 2. Plants that had both leaves removed and produced a fruit in 1987 decreased in size in the following 2 years in comparison with other treatment groups. The cost of fruit production was not apparent in plants that had only one or no leaves removed. Plants apparently have to be put into severe physiological stress in order for a cost of reproduction to appear in the following year. The cost of producing one fruit was a decline of plant size in the following year of 30 cm2, which is very similar to our previous experiment using a different design. An additional experiment failed to find evidence that these plants increase their photosynthetic rate to compensate for the loss of leaves or the cost of maturing fruit. Published experiments in both the greenhouse and the field that failed to find a cost of reproduction should be reevaluated in terms of the intensity of treatment imposed and the overall energy budget of the plant in field situations. 相似文献
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67.
野生大豆种子蛋白含量差异的生理及结构基础的探讨 总被引:1,自引:0,他引:1
利用SDS-聚丙烯酰胺凝胶电泳、电子显微镜、蛋白及酰脲含量测定等技术,对高蛋白含量(50.7% )的50359 和低蛋白含量(40.8% )的50305 两个野生大豆在种子发育过程中贮藏蛋白积累的速率、蛋白组分合成的起始时间、蛋白体发育的进程以及幼茎的酰脲含量进行了比较研究。结果表明:野生大豆50359的高蛋白含量是与其种子发育过程中较高的植株酰脲含量、较早较快的贮藏蛋白合成及积累速率,液泡中高效的蛋白贮藏方式以及蛋白体在子叶细胞中占有较大体积相联系的 相似文献
68.
双价外壳蛋白基因植物表达载体的构建及马铃薯转基因植株的鉴定 总被引:10,自引:0,他引:10
在克隆了马铃薯X病毒(PVX)、马铃薯Y 病毒(PVY)和马铃薯卷叶病毒(PLRV)的外壳蛋白基因的基础上,构建同时包含PVX和PVY 与PVY 和PLRV 两个外壳蛋白基因植物表达框架的表达载体,通过农杆菌(Agrobacterium tumefaciens)介导转化烟草(Nicotianatabacum )和生产上常用的几个马铃薯(Solanum tuberosum )优良品种:“Favorita”、“虎头”、“克4”。经PCR检测证明外源基因已整合到植物的染色体上,得到批量转基因植株。在转PVX+PVY 外壳蛋白基因的烟草上接种PVX (5 μg/m L)、PVY(20 μg/m L)病毒,得到有一定抗性的植株 相似文献
69.
Vivek R. Nerurkar Ki-Joon Song Rebecca R. Melland Richard Yanagihara 《Molecular neurobiology》1994,8(2-3):155-173
Molecular variants of human T-cell lymphotropic virus type I (HTLV-I) have been isolated recently from lifelong residents
of remote Melanesian populations, including a Solomon Islander with tropical spastic paraparesis/HTLV-I-associated myelopathy
(TSP/HAM) or HTLV-I myeloneuropathy. To clarify the genetic heterogeneity and molecular epidemiology of disease-associated
strains of HTLV-I, we enzymatically amplified, then directly sequenced representative regions of thegag, pol, env, andpX genes of HTLV-I strains from Melanesians with and without TSP/HAM, and aligned and compared these sequences with those of
HTLV-I strains from patients with TSP/HAM or adult T-cell leukemia/lymphoma and from asymptomatic carriers from widely separated
and culturally disparate populations. Overall, the HTLV-I variant from the Solomon Islander with TSP/HAM, like HTLV-I strains
from asymptomatically infected Melanesians, diverged by approx 7% from cosmopolitan HTLV-I strain. No disease-specific viral
sequences were found. Gene phylogenies, as determined by the unweighted pair-goup method of assortment and by the maximum
parsimony method, indicated that the Melanesian and cosmopolitan strains of HTLV-I have evolved along separate geographically
dependent lineages, one comprised of HTLV-I strains from Papua New Guinea and the Solomon Islands, and the other composed
of virus strains from Japan, India, the Caribbean, Polynesia, the Americas, and Africa. The total absence of nonhuman primates
in Papua New Guinea and the Solomon Islands precludes any possibility that the Melanesian HTLV-I strains have evolved recently
from the simian homolog of HTLV-I. 相似文献
70.
酶电泳资料和系统与进化植物学研究综述 总被引:39,自引:0,他引:39
酶电泳资料和系统与进化植物学研究综述葛颂(中国科学院植物研究所系统与进化植物学开放研究实验室北京100093)关键词同工酶,电泳,植物系统学,进化ELECTROPHORETICDATAANDSTUDIESOFPLANTSYSTEMATICSANDEV... 相似文献