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1.
The Escherichia coli dnaW mutation is an allele of the adk gene 总被引:3,自引:0,他引:3
Joan M. Henson Aleksandra Blinkowa James R. Walker 《Molecular & general genetics : MGG》1982,186(4):488-492
Summary A dnaW mutant, isolated on the basis of inability to effect conjugal DNA transfer at high temperature, has been shown by complementation and enzyme assay to be defective in the adk (adenylate kinase; EC 2.7.4.3) locus. The adk mutant, known to have reduced ATP concentration at the nonpermissive temperature (Cousin and Belaich 1966), was used to demonstrate a donor energy requirement for stable aggregate formation and for chromosome transfer in conjugation. 相似文献
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Assignment of the human gamma-glutamyl transferase gene to the long arm of chromosome 22 总被引:3,自引:0,他引:3
F. Bulle M. G. Mattei S. Siegrist A. Pawlak E. Passage M. N. Chobert Y. Laperche G. Guellaën 《Human genetics》1987,76(3):283-286
Summary We have determined the chromosomal location of the human gene for gamma-glutamyltransferase (GGT). This study was done by in situ hybridization of human metaphase spreads with a rat cDNA probe specific for this enzyme and constructed from two clones previously characterized in our laboratory. The final construct had a 1.6-kb-long insert covering 92% of the coding sequence for GGT. The new insert was also freed of any GC tails introduced for the cDNA cloning, because we observed that these sequences were responsible for a high background. Using this probe for the analysis of 136 human metaphase spreads, we observed a strong specific signal on chromosome 22 at the interface of q111-112 and a minor peak in q131. Thus GGT might represent a new marker for the study of certain diseases which have chromosomal abnormalities at these loci. 相似文献
4.
Lidija Simova Carolyn Williams Georgi D. Efremov Aleksandra Gordova-Muratovska Stojka Suštić Eila K. Watson Robert Williamson 《Human genetics》1990,85(4):432-433
Summary Chromosomes from 19 unrelated Southern Yugoslav families in which cystic fibrosis (CF) occurs were analysed for the presence
of the ΔF508 mutation, using polymerase chain reaction amplification followed by dot blot and polyacrylamide gel analysis.
Of the 38 CF chromosomes, 15 (39.5%) carry the ΔF508 deletion. Restriction fragment length polymorphism haplotypes for KM19/PstI, XV2c/TaqI and J3.11/PstI marker loci were determined and are compared for a total of 34 N and 37 CF chromosomes. 相似文献
5.
gamma-Glutamyl transpeptidase: a single copy gene in the rat and a multigene family in the human genome 总被引:5,自引:0,他引:5
A Pawlak O Lahuna F Bulle A Suzuki N Ferry S Siegrist N Chikhi M N Chobert G Guellaen Y Laperche 《The Journal of biological chemistry》1988,263(20):9913-9916
gamma-Glutamyl transpeptidase (GGT) genomic sequences were isolated from rat and human libraries using a rat GGT cDNA as a cross-species hybridization probe. Characterization of the human GGT clones by restriction mapping clearly establishes that at least four different GGT genes or pseudogenes are present in the human genome. All the rat genomic clones cover a 12.5-kilobase sequence and exhibit a unique restriction pattern. A precise quantitation of the rat GGT gene copy number by Southern blot analysis demonstrates that this sequence is present as a single copy/rat haploid genome. Therefore, the GGT gene organization is different between rat and human species; this raises the possibility of different regulatory mechanisms in the two species. 相似文献
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The mode of action of cytotoxic and antitumor 1-nitroacridines and their isomeric derivatives was studied by comparing their effects in cell-free systems and towards cultured tumor HeLa cells, assuming that the nitroacridines considered exert cytotoxic effects by physicochemical binding with the DNA. All the nitroacridines impaired biosyntheses of DNA, RNA and protein in cultured HeLa cells and a causal relationship between nitroacridine inhibition of macromolecular biosyntheses and lethal effects of the agents appears likely. In cell-free systems, the nitroacridines bound with two independent sites on the DNA, forming complexes with enhanced resistance to DNA strand separation upon melting and inhibited the DNA polymerase reaction by altering activity of template and/or of enzyme. The 1-nitroacridines were poorly effective in cell-free systems and were the most potent inhibitors toward the growth of HeLa cells among the derivatives studied. It is concluded that the primary events responsible for cytotoxic effects of antitumor 1-nitroacridines and of their isomeric derivatives are different. The metabolic activation of 1-nitroacridines to more reactive intermediates which will attach to and alter the structure and/or function of DNA of sensitive cells is suggested. 相似文献
8.
Zur Systematik und Ökologie (Lebenszyklen,Populationsdynamik) der Turbellarien-GattungParomalostomum
R. Pawlak 《Helgoland Marine Research》1969,19(3):417-454
This paper contributes to the systematics, the ecology and the biology of sexual reproduction of psammobiontic macrostomid Turbellaria from a sandy beach on the eastern shore of the island Sylt. The anatomy of a new species,Paromalostomum proceracauda, is described. The cuticular structures of the genital apparatus ofParomalostomum fusculum Ax,P. dubium (de Beauchamp) andHaplopharynx rostratus Meixner are analyzed.P. fusculum is one of the most frequent turbellarians living in the sandy flats (Sandwatt) in front of the Litoralstation of the Biologische Anstalt Helgoland in List. This species shows obvious seasonal differences in it's vertical distribution. In summer,P. fusculum lives in the upper 4 cm of the sand while in winter, the animals move to the deeper strata of the sediment, were they are more protected from low temperatures.P. fusculum has an annual life-cycle. The period of reproduction lasts from May to July. The new generation hibernates in the state of male maturity and attains female maturity in spring. After the period of egg-shedding, large animals individuals are seldom found; it is supposed that they die after spawning. The mechanism of egg-shedding and the structure of the egg are described. The egg-shells ofP. fusculum are distinguished from those ofP. dubium by the presence of opercula. 相似文献
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10.
Milutin Miri Aleksandra Mikovi Sran Brki Jovan Vasiljevi Nenad Keserovi Milan Pei 《FEMS immunology and medical microbiology》1994,10(1):65-74
Abstract The randomized clinical trial with interferon-α (IFN) or thymic hormones versus conventional therapy was conducted in patients with myocarditis and idiopathic dilated cardiomyopathy (IDC). We enrolled 180 patients to receive IFN (3–5 million units per day) for 3 months, thymomodulin (10 mg three times per week) for 2 months, or conventional therapy alone. Patients were followed-up for 7 years after the end of treatment. Left ventricular function, exercise tolerance and survival rate were significantly better at long-term follow-up in patients treated with IFN or thymomodulin, than in conventionally treated patients. These results implicate that immune modulating therapy might represent important contribution in the treatment of myocarditis and IDC. 相似文献