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排序方式: 共有383条查询结果,搜索用时 31 毫秒
1.
Using the imidate procedure, 2,3,4,6-tetra-O-benzyl-1-O-(N-methylacetimidoyl)-β-d-galactopyranose was condensed with various monosaccharides to provide, in good yield and with high stereoselectivity, α-linked disaccharides. 相似文献
2.
Two NADP-isocitrate dehydrogenase isoenzymes designated as NADP-IDH1 and NADP-IDH2 (EC 1.1.1.42) were identified in pea (Pisum sativum) leaf extracts by diethylaminoethylcellulose chromatography. The predominant form was found to be NADP-IDH1 while NADP-IDH2 represented only about 4% of the total leaf enzyme activity. These enzymes share few common epitopes as NADP-IDH2 was poorly recognized by the specific polyclonal antibodies raised against NADP-IDH1, and as a consequence NADP-IDH2 does not result from a post-translational modification of NADP-IDH1. Subcellular fractionation and isolation of chloroplasts through a Percoll gradient, followed by the identification of the associated enzymes, showed that NADP-IDH1 is restricted to the cytosol and NADP-IDH2 to the chloroplasts. Compared with the cytosolic isoenzyme, NADP-IDH2 was more thermolabile and exhibited a lower optimum pH. The data reported in this paper constitute the first report that the chloroplastic NADP-IDH and the cytosolic NADP-IDH are two distinct isoenzymes. The possible functions of the two isoenzymes are discussed.Abbreviations BSA
bovine serum albumin
- DEAE
diethylaminoethyl
- NADP-IDH
NADP-isocitrate dehydrogenase
- NADP-IDH1
cytosolic NADP-IDH
- NADP-IDH2
chloroplastic NADP-IDH 相似文献
3.
Monique Berthelon Catherine Caillaud Françoise Rey Philippe Labrune Dominique Melle Josué Feingold Jean Frézal Marie-Louise Briard Jean-Pierre Farriaux Pierre Guibaud Hubert Journel Bernard Le Marec Nicole Maurin Jean-Louis Nivelon Henri Plauchu Jean-Marie Saudubray Philippe Tron Jean Rey Arnold Münnich Stanislas Lyonnet 《Human genetics》1991,86(4):355-358
Summary A total of 252 chromosomes from 126 patients with phenylalanine hydroxylase (PAH) deficiencies were analyzed for both mutant genotypes and restriction fragment length polymorphism (RFLP) haplotypes at the PAH locus. The mutant genes studied originated either from Western Europe (116 alleles) or from Mediterranean countries (136 alleles). Only 27% of all mutant alleles were found to carry identified mutations, particularly mutations at codon 252 (2.3%), 261 (7.5%), 280 (6.3%), 408 (3.5%) and at the splice donor site of intron 12 (6.3%). The mutant genotypes were associated with RFLP haplotypes 7, 1, 38, 2 and 3 at the PAH locus respectively. Except for the splice mutation of intron 12, these associations were preferential, but not exclusive, since the other four mutations were found on the background of at least two RFLP haplotypes. These results, together with the observation that 85% of PAH deficient patients are heterozygotes for their mutant genotypes, emphasize the great heterogeneity of PAH deficiencies in Mediterranean countries and hamper systematic DNA testing for carrier status in this population. 相似文献
4.
Albert Faradji Alain Bohbot Marion Schmitt-Goguel Norbert Roeslin Serge Dumont Marie-Louise Wiesel Christian Lallot Michel Eber Jacques Bartholeyns Philippe Poindron Georges Morand Jean-Paul Witz Francis Oberling 《Cancer immunology, immunotherapy : CII》1991,33(5):319-326
Summary The purpose of this phase I study was to evaluate the toxicity and biological activity of autologous blood-derived macrophages activated ex-vivo with recombinant human interferon (rhuIFN) [monokine-activated killer (MAK) cells] and administered intravenously to 11 lung cancer patients once a week for 6 consecutive weeks. Peripheral blood monocytes were collected by leukapheresis and then purified by counterflow elutriation. The MAK cells were generated by culturing the purified monocytes in Teflon bags for 7 days and adding rhuIFN to the cultured cells for the last 18 h. These MAK cells expressed differentiation-associated surface antigen MAX1, and were cytotoxic in vitro against tumour cell line U937. The MAK cells were infused at dose levels from 1 × 107 to 5 × 108 on an intrapatient dose-escalating schedule. No severe adverse side-effects occurred. Toxicity was mild to moderate [primarly fever (75%) and chills (32%)], non-dose-dependent, and non-cumulative. No consistent change in haemostatic function, or liver or renal function was observed. Dose-limiting toxicity was not reached at 5 × 108 cells (optimal dose reproduced for each patient). The maximum tolerated dose was not determined. The immunomodulatory activity of i.v. infused MAK cells was demonstrated both in vivo by significant increases in granulocyte count and neopterin level in the patients' peripheral blood postinfusion and in vitro by secretory products (IL-1. TNF, neopterin, and thromboplastin-like substance) in the culture supernatants. The in vivo traffic patterns of autologous MAK cells labelled ex-vivo with111In oxine were studied in 7 patients. Gamma imaging showed an immediate but transient lung uptake (<24 h), and a progressive uptake of radioactivity in the liver and spleen was seen from 6 h to 72 h post-infusion. Our results indicate that the preparation of high numbers of autologous, blood-derived MAK cells is a feasible procedure, and their transfusion is safe for patients. This immunotherapeutic approach seems to be encouraging from the point of view of establishing an adjuvant therapeutic modality in cancer patients with minimal residual disease.This work was supported in part by a grant 6911 from the Association pour la Recherche contre le Cancer (ARC), grants from the Ligue Nationale contre le cancer and the Ligues Regionales (Bas-Rhin, Haut-Rhin) contre le cancer, and contract 891013 from the Institut National pour la Santé et la Recherche Médicale (INSERM), France 相似文献
5.
C-Glycosylation of 5,7-dihydroxy-3′,4′,5′-trimethoxyflavone was carried out with acetobromo-α-d-glucose, -α-d-galactose, -α-d-xylose, -β-l-arabinose and -αt-L-rhamnose. The respective 6-C-glycosides and 6, 8-di-C-glycosides (excepted for galactose) were isolated and permethylated. MS and TLC comparison confirmed the proposed structures of five natural tricetin-derived C-glycosides. 相似文献
6.
A fluorescent pigment was isolated from the culture fluid of Methanobacterium thermoautotrophicum strain H. This pigment was shown to be 7,8-didemethyl-8-hydroxy-5-deazariboflavin by various spectroscopic and chromatographic techniques. This compound was previously described as the FO acid hydrolysis fragment of coenzyme F420. On the basis of the time of appearance of the pigment in the course of fermentation, it is suggested that this substance may be an over-produced biosynthetic precursor of F420. 相似文献
7.
Marie-Louise Bach 《Molecular & general genetics : MGG》1971,110(1):40-53
Summary The inactivation of transforming Haemophilus influenzae DNA by sonication in aqueous solution was investigated. The molecular weight decrease of the molecules is the major factor in DNA inactivation. It impairs strongly the uptake of the DNA by the recipient bacteria, especially when the molecular weight is lower than 3x106 daltons. The uptake of sonicated DNA by the bacterial cells seems not to be further reduced when molecules of about 0.5x106 daltons are submitted to further depolymerisation. However the transforming activity of these molecules is still sensitive to further sonication. The transforming activity of the sonicated DNA is related in the last resort to the intact length of the DNA molecules, at the level of their single-strand structure, available for recombination. Rupture by ultrasound was found to be twice as efficient in reducing transforming activity as a nick induced by pancreatic DNAse. 相似文献
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10.
The brain organization of butterflyfishes 总被引:2,自引:0,他引:2
Roland Bauchot Jean-Marc Ridet Marie-Louise Bauchot 《Environmental Biology of Fishes》1989,25(1-3):205-219
Synopsis The encephalization indices of angelfishes (Pomacanthidae) and butterflyfishes (Chaetodontidae) are typical of advanced perciform
fishes: both families lie in the upper part of the polygon of teleost indices. The chaetodontids seem to be a little more
encephalized than pomacanthids. The general morphology of the brains in both families is very similar: small olfactory bulbs,
large optic tectum and a cerebellum which covers the brain structures in front of it like a cap. This morphology is shared
by another family of the coral reef biotope, the Acanthuridae. The histological architecture is also typical of advanced teleosts,
with a cortex-like pallium, a laminated nucleus geniculatus (= pretectalis superficialis), a complex valvula cerebelli and
a corpus glomerulosum with a clear neuropile centre. The quantitative analysis of the main subdivisions of the brain, either
from relative volumes or from indices, shows small olfactory bulbs (microsmy) but important telencephalic and diencephalic
centres, large tectal centres (vision) and large cerebellum (precise locomotion). Many of these peculiarities are shared by
other fishes inhabiting coral reefs. The differences between the two families seem to be primarily correlated with food habits:
the angelfishes, which are sponge-feeders and may have an overweight due to the ballast of the sponge-skeleton in their digestive
tract, and which do not need either such good vision or such precise locomotion to pick up their prey, could be a little less
encephalized than the butterflyfishes. 相似文献