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31.
Formation of lymphocyte colonies under serum-free culture conditions in normal individuals and patients with chronic lymphocytic leukemia 总被引:1,自引:0,他引:1
Y C Dai G Z Hu H Y Niu Z Wen Z Fang X G Lu J Li Q Wu Y P Huang R Wen 《International journal of cell cloning》1987,5(6):480-491
This paper describes a culture system which supports the formation of B cell and some T cell colonies under serum-free conditions in peripheral blood samples of normal individuals and patients with chronic lymphocytic leukemia (CLL) of B cell type. In this system, serum is replaced by bovine serum albumin, transferrin, cholesterol, insulin and catalase or horseradish peroxidase. In addition, it is necessary to add staphylococcus protein A, mitomycin-treated T cells as feeders and phytohemagglutinin leukocyte-conditioned medium as a source of growth factors. The plating efficiency is greatly enhanced when normal cells are incubated with galactose oxidase prior to plating and when CLL cells are exposed sequentially to neuraminidase and galactose oxidase. 相似文献
32.
Peter Kaastrup René J. M. Stet Albert J. Tigchelaar Egbert Egberts Willem B. van Muiswinkel 《Immunogenetics》1989,30(4):284-290
In this study, experiments are described that were designed to investigate whether fish have an immune regulatory systems
similar to the major histocompatibility complex (MHC) in higher vertebrate species. From combinations of gynogenetic carp
showing either slow of fast rejection of skin transplants, the latter were chosen for alloantiserum production by hyperimmunization
with peripheral blood leucocytes. The resulting alloantisera were analyzed for hemagglutinating reactivity with gynogenetic
siblings and proved to be operationally monoscpecific in absorption experiments. The serologically determined carp erythrocyte
specificites were shown to correspond to two codominantly expressed allelic products of a single locus and were designated
K1 and K2, respectively. Flow cytometer analysis revealed that the same products are also present on leucocytes from peripheral
blood, thymus, spleen, and pronephros.K1-andK2-homozygous second-generation gynogenetic siblings were used to study the histocompatibiligy nature of the K locus products.
Skin transplants between K-allogeneic gynogenetic siblings were rejected significantly faster than within K-syngeneic combinations.
Taken together, these data suggest that theK locus incorporates MHC class I-like characteristics. 相似文献
33.
Nora Goosen Harold P. A. Horsman René G. M. Huinen Arjan de Groot Pieter van de Putte 《Antonie van Leeuwenhoek》1989,56(1):85-91
From a gene bank of theAcinetobacter calcoaceticus genome a plasmid was isolated that complements four different classes of PQQ- mutants. Subclones of this plasmid revealed that the four corresponding PQQ genes are located on a fragment of 5 kilobases. The nucleotide sequence of this 5 kb fragment was determined and by means of Tn5 insertion mutants the reading frames of the PQQ genes could be identified. Three of the PQQ genes code for proteins of Mr 29700 (gene I), Mr 10800 (gene II) and Mr 43600 (gene III) respectively. In the DNA region where gene IV was mapped however the largest possible reading frame encodes for a polypeptide of only 24 amino acids. A possible role for this small polypeptide will be discussed. Finally we show that expression of the four PQQ genes inAcinetobacter lwoffi andEscherichia coli lead to the synthesis of the coenzyme in these organisms. 相似文献
34.
Summary DNA markers in the pericentromeric region of human chromosome 21 have shown linkage to a gene for Familial Alzheimer disease (FAD; St. George Hyslop et al. 1987). The limited informativeness of probes for the loci D21S13 and D21S16 have hindered precise mapping of the FAD locus and analysis of non-allelic heterogeneity in FAD (Schellenberg et al. 1988; St. George-Hyslop et al. 1987). We recently described a new EcoRII polymorphism at the D21S13 locus that was very informative in a large FAD pedigree (Pulst et al. 1990a, b). We now report another polymorphism for the D21S13 locus that further increases the informativeness of this locus. 相似文献
35.
The effect of dynamic exercise on the NADH content of human type I (slow-twitch) and II (fast-twitch) muscle fibres was investigated. Muscle biopsy samples were obtained from the quadriceps femoris of seven healthy subjects at rest and after bicycle exercise at 40, 75 and 100% of the maximal oxygen uptake [VO2(max.)]. At rest and after exercise at 100% VO2(max.), muscle NADH content was significantly higher (P less than 0.05) in type I than in type II fibres. After exercise at 40% VO2(max.), muscle NADH decreased in type I fibres (P less than 0.01), but was not significantly changed in type II fibres. After exercise at 75 and 100% VO2(max.), muscle NADH increased above the value at rest in both type I and II fibres (P less than 0.05). Muscle lactate was unchanged at 40% VO2(max.), but increased 20- and 60-fold after exercise at 75 and 100% VO2(max.) respectively. The finding that NADH decreased only in type I fibres at 40% VO2(max.) supports the idea that type I is the fibre type predominantly recruited during low-intensity exercise. The increase of NADH in both fibre types after exercise at 75% and 100% VO2(max.) suggests that the availability of oxygen relative to the demand is decreased in both fibre types at high exercise intensities. 相似文献
36.
Christiane Levrat Dominique Ardail Renée Morelis Pierre Louisot 《Glycoconjugate journal》1988,5(4):449-466
The results reported in this paper show two distinct ways for the incorporation ofN-acetylglucosamine into mitochondrial outer membranes. The first one is the glycosylation of dolichol acceptors, which is indicated by the inhibition of the synthesis of these products by the inhibitors of the dolichol intermediates (tunicamycin and GDP). The second one is the incorporation ofN-acetylglucosamine into protein acceptors directly from UDP-N-acetylglucosamine. This second way of glycosylation is only localized in mitochondria outer membranes.The existence of a direct route forN-glycoprotein biosynthesis has been based on the following evidence. First, the synthesis of theN-acetylglucosaminylated protein acceptors was not inhibited by tunicamycin or GDP. Second, the addition of exogenous dolichol-phosphate did not change the rate of biosynthesis of glycosylated protein material. Third, the sequential incorporation ofN-acetylglucosamine and mannose from their nucleotide derivatives in the presence of GDP and tunicamycin led to the synthesis of glycosylated protein material which entirely bound to Concanavalin A-Sepharose. The oligosaccharide moiety of the glycosylated protein material resulting from the direct transfer of sugars from their nucleotide derivatives to the protein acceptor is of theN-glycan type. On sodium dodecylsulphate polyacrylamide gel electrophoresis, this glycosylated material migrated as a marker protein with a molecular weight between 45 000 and 63 000. HPLC chromatofocusing analysis revealed that the fraction studied was anionic. The oligosaccharide moiety of the glycoprotein material can only be elongated by the incorporation ofN-acetylglucosamine and galactose from their nucleotide derivatives. 相似文献
37.
T Isobe Y I Fang D Muno T Okuyama D Ohmori F Yamakura 《Biochemistry international》1988,16(3):495-501
Alignment of the amino acid sequences of the Pseudomonas ovalis and Photobacterium leiognathi iron-superoxide dismutases (Fe-SODs) with the known sequences of the manganese-superoxide dismutases (Mn-SODs) shows that both types of SOD are highly homologous (33-53% identity) and share residues for the metal coordination. The amino acid residues that form the environment of the metal ions appear to be also conserved between the Fe- and Mn-SODs, except that the Phe-84 and Gln-154 in the Mn-SODs are replaced by Tyr and Ala, respectively, in the Fe-enzymes. Since this latter residue contributes to formation of the hydrophobic metal-ligand environment through hydrogen bonding with Trp-133 and Tyr-34 in the Mn-SODs, its substitution by Ala should cause different micro environments between the metal centers of the Fe- and Mn-SODs. This difference may account for the metal specificity of both types of SODs demonstrated by previous reconstitution experiments. 相似文献
38.
ent-Kaurene Synthesis and Endogenous Levels of Gibberellins in a Shoot Forming Tobacco Crown Gall Tissue 总被引:1,自引:0,他引:1
Mettrie Ren?e; de Greef Jan; Nakagawa Sachiko; Sakurai Akira 《Plant & cell physiology》1988,29(5):777-784
The in vitro ent-Mcaurene synthesizing capacity, as well asthe endogenous GA content of shoot-forming tobacco crown gallsinduced by a nopaline-type Ti plasmid, was studied. For determinationof the ent-kaurene synthesizing capacity, an HPLC procedurepreceded by sample clean-up was used and the GA content wasexamined by GC-SIM. Kaurene synthesis reached a maximum at thebeginning of the logarithmic phase of growth. There was a clearcorrelation between the ent-kaurene synthesizing capacity andthe content of C20-GAs. It seems that gibberellin synthesisis related to growth and development of the tissue. The natureof the GAs identified suggests, that the GA metabolism mightbe an unusual one. (Received October 12, 1987; Accepted April 11, 1988) 相似文献
39.
40.
为探讨依兰花精油的香气质量,我们对云南省西双版纳产依兰花精油以及引种栽培于西双版纳的泰国种、老挝种的依兰花精油的化学成分在Finnigan-4510 GC/MS/DS上用毛细管柱进行了定性和定量分析,鉴定了44个化学成分。分析结果表明,依兰油的香气与品种及精油中的酯类、醇类和酚醚的含量有关。倍半萜烯类和倍半萜醇类的含量越高,其香气质量越差。就西双版纳产依兰油的香气而言,依兰花由青转黄时得到的精油远较绿花和花蕾油为好。 相似文献