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31.
32.
Structure of the human alpha 1-acid glycoprotein gene: sequence homology with other human acute phase protein genes. 总被引:16,自引:4,他引:12
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We have determined the sequence coding for human alpha 1-acid glycoprotein from two independently isolated cDNA clones and a genomic clone. The aminoacid sequences deduced from the three clones, deriving from three different individuals, are identical. Southern blot analysis on human DNA indicates that there are at least two genes coding for alpha 1-AGP. We propose that alpha 1-AGP found in plasma is a mixture of the products of these two different genes. This is the simpler explanation for the heterogeneity in the aminoacid composition in purified alpha 1-AGP observed by Schmid et al. (1). DNA sequence comparison with cDNA clones coding for human alpha 1-antitrypsin and haptoglobin shows a conserved sequence within the 5' untranslated region which may play a role in the acute phase response. 相似文献
33.
The primary structure of human hemopexin deduced from cDNA sequence: evidence for internal, repeating homology. 总被引:9,自引:0,他引:9
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F Altruda V Poli G Restagno P Argos R Cortese L Silengo 《Nucleic acids research》1985,13(11):3841-3859
We have cloned and analyzed a cDNA containing the coding sequence for human hemopexin. We have first identified, by immunological screening of 30.000 colonies of a liver cDNA library in the expression vector pEX1, a clone carrying an insert 1170 base pairs long that shows 100% homology with a known human hemopexin peptide. The complete sequence coding for hemopexin was isolated from a liver cDNA library in the vector pAT218. The DNA insert of 1523 base pairs shows an open reading frame coding for 439 amino acids, a 3' noncoding region of 159 nucleotides long, followed by a poly(A) tail. The insert spans the entire coding region and from which the primary structure of the protein was deduced. By computer assisted analysis of the amino acid sequence, it was possible to recognize a core unit, of about 45 amino acids, which is repeated 8 or possibly even 10 fold along the polypeptide chain. This feature suggests that the gene might have evolved through a series of duplications. This characteristic, together with prediction of secondary structure, suggest a rough model for the tridimensional folding that allows some speculations on the function of hemopexin. Blot hybridization of total RNA from human liver with nick translated hemopexin cDNA detected a message of about 1600 nucleotides. Southern blot experiments to identify the hemopexin gene (s) suggest that it is not a large multi-gene family, but that there is only one or at most a few genes in the human genome. 相似文献
34.
Violeta Datcheva Aleksei Kamernitskii Radoslav Vlahov Natalia Voishvillo Vera Levi Irina Reshetova Elena Chernoburova 《Applied microbiology and biotechnology》1986,25(1):14-17
Summary A high-yield microbiological transformation of polyfunctional 5-3-acetoxy steroids, containing an additional ring E, by Corynebacterium mediolanum strain B-964 was carried out, resulting in the corresponding 4-3-ketones. It was shown that the type of transformation and the yield of the reaction depend on the degree of saturation of the ring E and on the position of the oxygen-containing substituents in it. 相似文献
35.
To determine the value of serum arabinitol concentrations in clinical practice, we identified all patients at the University of Utah Medical Center for whom a serum arabinitol determination had been requested by the attending physician or housestaff to assist in the management of candidiasis. The patient populaton was divided into three categories on the basis of clinical and pathological findings: (1) superficial candidiasis, (2) possible deep, invasive candidiasis, and (3) definite, deep invasive candidiasis. Abnormal renal function was associated with elevated concentrations of serum arabinitol in proportion to the degree of renal dysfunction. Both the serum arabinitol concentration and the arabinitol/creatinine ratio were increased in the combined patient population with candidiasis relative to normal uninfected controls (p=0.06 and 0.001, respectively). However, neither of these tests reliably distinguished patients with invasive candidiasis from those with only superficial candidal disease. 相似文献
36.
Elena B. Rodriguez de Turco Susana Morelli de Liberti Nicolas G. Bazan 《Journal of neurochemistry》1983,40(1):252-259
The pool size and composition of free fatty acids (FFA) and diglycerides (DG) from the cerebrum and cerebellum of rats undergoing bicuculline-induced seizures were studied. A fourfold increase in cerebral FFA occurred 3-4 min after bicuculline injection; arachidonic and stearic acids were the principal fatty acids accumulated. Cerebellar FFA also increased, but to a lesser extent. An increased production of arachidonic acid took place in the cerebrum as a function of time after bicuculline injection. Other fatty acids produced were oleic, palmitic, and docosahexaenoic acids. A twofold increase in cerebral arachidonic acid was seen at the time of the first generalized tonic-clonic convulsion. However, a 13- to 17-fold increase in arachidonic acid was seen approximately 5-6 min after bicuculline injection. The rise in other FFA was much smaller. Stearoyl- and arachidonoyl-DG were also accumulated. The drug alpha-methyl-p-tyrosine was found to (a) potentiate the bicuculline-stimulated release of cerebellar FFA, and (b) inhibit by 70% the production of stearoyl- and arachidonoyl-DG in the cerebrum and cerebellum. Basal production of FFA was stimulated by p-chlorophenylalanine, but the drug had no effect on the bicuculline-induced changes. Hydrolysis of phospholipids enriched in stearoyl-arachidonoyl groups, such as phosphatidylinositol of excitable membranes, may be stimulated during seizures. 相似文献
37.
Cloning and sequencing of a full length cDNA coding for human retinol-binding protein. 总被引:12,自引:3,他引:9
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V Colantuoni V Romano G Bensi C Santoro F Costanzo G Raugei R Cortese 《Nucleic acids research》1983,11(22):7769-7776
We have isolated and sequenced a cDNA clone coding for human Retinol Binding Protein. The sequence indicates that Retinol Binding Protein is synthesized as a single polypeptide chain precursor which is then matured to the secreted protein by removal of a leader peptide. Southern and Northern blot analysis suggest that the gene is present in one or few copies per haploid genome and is transcribed in a single mRNA species. 相似文献
38.
Sequence of human haptoglobin cDNA: evidence that the alpha and beta subunits are coded by the same mRNA. 总被引:10,自引:3,他引:7
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G Raugei G Bensi V Colantuoni V Romano C Santoro F Costanzo R Cortese 《Nucleic acids research》1983,11(17):5811-5819
We have isolated and sequenced a cDNA clone coding for human haptoglobin. Our sequence shows that haptoglobin is very likely synthesized as a single polypeptide chain which is then cleaved at an Arg residue to generate its two characteristic alpha and beta subunit. Southern blot analysis suggests that there are at least two copies of the haptoglobin gene per haploid genome. 相似文献
39.
Evidence for two waves of induction of DNA enzymes in stimulated human lymphocytes 总被引:5,自引:3,他引:2
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Guido C. F. Pedrali Noy Leda Dalpra Antonia M. Pedrini Giovanni Ciarrocchi Elena Giulotto Fiorella Nuzzo Arturo Falaschi 《Nucleic acids research》1974,1(9):1183-1199
The stimulation of human lymphocytes with phytohaemoagglutinin induces the appearance or increase of several enzymes of DNA metabolism [Pedrini etal., Biochem. Biophys. Res. Comm., 47:1221(1972)]. With long times of stimulation, two phenomena are observed; an increase in the levels of DNA polymerase, of a DNase acting on single-stranded DNA, and of an endonuclease, occurring between the third and fourth day, in parallel with a wave of DNA synthesis;a second wave of increase of the same enzymes and of DNA ligase,occurring between the fifth and eight day when the DNA replication rate, as measured by thymidine-pulses, has decreased to values close to the background. 相似文献
40.
Stand microclimate and physiological activity of tree leaves in an oak-hornbeam forest 总被引:1,自引:0,他引:1
Michal Marek Elena Masarovičovà Irena Kratochvílová P. Eliáš D. Janouš 《Trees - Structure and Function》1989,3(4):234-240
Summary In an uneven-aged, multi-species oak-hornbeam forest at Báb, SW Slovakia (former IBP Forest Research Site), a series of micrometeorological and ecophysiological measurements started in 1985. The aims of the work are to improve understanding of physiological processes (photosynthesis, respiration, and transpiration) of adult trees and stand microclimate, to collect data for simulation of the canopy (stand) photosynthesis and for ecological synthesis of the functioning of the forest ecosystem. In this paper, photosynthetically active radiation (PAR), air temperature (AT) and relative humidity (RH), wind speed (WS), and CO2 concentration ([CO2]) in and above the forest are characterized for the fully leaved season, using diurnal courses, vertical profiles and isodiagrams (isopleths). Approximately 50% of incident PAR was absorbed by the upper 4–5 m layer of leaves and only approximately 5% or less penetrated to the forest floor. Vertical gradients of AT and RH were generally low, but large differences in diurnal ranges of AT and RH were observed between vertical levels. The upper leaf canopy greatly reduced WS, and at a height of about 14 m above the ground it was close to zero. The highest diurnal [CO2] maximum and variations occurred at 1 m above the ground, and the lowest above the forest. In good light conditions in the forest, the entire leaf canopy (overstorey and understorey canopy) is a large sink of CO2. At night the forest stand is a source of CO2, the largest internal source being the soil and forest floor. 相似文献