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41.
42.
一种模拟高原低氧复合冷冻的简易动物实验舱 总被引:3,自引:3,他引:0
以氮稀释法使舱内氧含量维持实验模拟高度,以普通冰箱制冷系统维持舱内恒温,以多功能低温浴槽作为致冻装置。该舱可于20min内升至模拟6000m高度,每次可供16只大鼠作高原冻伤实验。实验期间高度恒定于6000±200m,舱温21±1℃。相对湿度55%±15%,冷冻液-25.0±0.5℃。该舱结构简单、使用方便,可在实验室中模拟高原条件进行冷冻实验研究。由于不使用人体减压舱,不仅避免了减压缺氧对实验人员的不利影响,也减少了实验消耗。 相似文献
43.
L. Qu J. F. Hancock 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,91(8):1309-1315
RAPD markers were used to determine the level of heterozygosity transmitted via 2n gametes from V. darrowi selection Florida 4B (Fla 4B) to inter-specific hybrids with tetraploid V. corymbosum cv Bluecrop. The tetraploid hybrid US 75 was found to contain about 70% of Fla 4B's heterozygosity, a value attributed to a first-division restitution (FDR) mode of 2n gamete production. Crossovers during 2n gamete formation were evidenced by the absence of 16 dominant alleles of Fla 4B in US 75, and direct tests of segregation in a diploid population involving Fla 4B. RAPD markers that were present in both Fla 4B and US 75 were used to determine the mode of inheritance in a segregating population of US 75xV. corymbosum cv Bluetta. Thirty-one duplex loci were identified which segregated in a 51 ratio, indicating that US 75 undergoes tetrasomic inheritance. 相似文献
44.
Regulation of cellulase synthesis in mycelial fungi: Participation of ATP and cyclic AMP 总被引:1,自引:0,他引:1
Summary ATP and cAMP in 4 strains of mycelial fungi were determined by luciferin-luciferase system and HPLC respectively. Cellulase synthesis was subject to the dual control of ATP and cAMP. No matter what carbon sourse was used, cellulase synthesis was repressed if intracellular ATP concentration was over 10-7mg/ml. Exogenous cAMP could increase cellulase synthesis under depression conditions. 相似文献
45.
P J Hurlin C Quéva P J Koskinen E Steingrímsson D E Ayer N G Copeland N A Jenkins R N Eisenman 《The EMBO journal》1995,14(22):5646-5659
46.
A chalcone synthase-like cDNA from rice anther 总被引:3,自引:0,他引:3
47.
Qu Zhengxing; Sharkey Robert M.; Hansen Hans J.; Goldenberg David M.; Leung Shui-on 《Glycobiology》1997,7(6):803-809
Two humanized antibody mutants, hLL2HCN1 and hLL2HCN5, engineeredwith CH1 domain-appended carbohydrates (CHOs) were generatedto facilitate site-specific conjugation of radionudides andanti-cancer drugs to antibodies. Such site-specific conjugationmay minimize the incidence of immunoreactlvity perturbationas is often observed with random conjugation. Since the compositionsand structures of CHOs are important in determining the chemistry,efficiency, and extent of conjugation, the sequences of theCH1-appended CHOs were determined by exoglycosidase digestionsand fluorophore-assisted CHO electrophoresis (FACE). The CHOspecies attached at HCN1 and HCN5 sites in hLL2HCN1 and IJLL2HCN5,respectively, were distinct from each other, heterogeneous,and extensively processed. All of these CHOs were corefucosylatedcomplex-type oligosaccharides and contained Gal (galactose)and GlcNAc (N-acetylglucosamine) residues in the outer branches.Some of the outer branches were composed of Gal 相似文献
48.
抗菌肽的固相合成,分离纯化与构效关系的研究 总被引:6,自引:0,他引:6
应用手工固相DCC/HOBt法合成CecropinB、Shival1、ABP3、WHD4种抗菌肽,各抗菌肽的C-端均为酰胺化,最终用HPLC分离纯化,这4种肽对大肠杆菌K12D31,野生型大肠杆菌,产气杆菌及4种植物病原菌青枯菌,临床致病理大肠杆菌,伤寒杆菌,硝酸盐杆菌均有明显的杀伤或抑制作用,对白血病细胞K560,肺癌细胞A549也有杀伤作用,其中尤以WHD杀伤作用最为明显,并用对其它3种肽不能 相似文献
49.
50.
Sequence variation and genetic diversity in the giant panda 总被引:3,自引:0,他引:3
ZHANG YapingOliver A. RyderFAN Zhiyong ZHANG HemingHE TingmeiHE Guangxin ZHANG Anju FEI LisongZHONG Shunlong CHEN HongZHANG Chenglin YANG Minghai ZHU Feibing PENG Zhenxin PU Tianchun CHEN Yucun YAO OMinda GUO Wei 《中国科学:生命科学英文版》1997,40(2):210-216
About 336–444 bp mitochondrial D-loop region and tRNA gene were sequenced for 40 individuals of the giant panda which were
collected from Mabian, Meigu, Yuexi, Baoxing, Pingwu, Qingchuan, Nanping and Baishuijiang, respectively. 9 haplotypes were
found in 21 founders. The results showed that the giant panda has low genetic variations, and that there is no notable genetic
isolation among geographical populations. The ancestor of the living giant panda population perhaps appeared in the late Pleistocene,
and unfortunately, might have suffered bottleneck attacks. Afterwards, its genetic diversity seemed to recover to some extent.
Project supported by the “8.5” Key Project of Chinese Academy of Sciences, the Chairman Foundation of Chinese Academy of Sciences,
K. C. Wang Education Foundation, the Applied Basic Research Foundation of Yunnan, the National Natural Science Foundation
of China, the Special Foundation for Returned Chinese Scientists, and Zoological Society of San Diego. 相似文献