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31.
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G Licata R Scaglione M A Dichiara G Parrinello G Capuana D Di Vincenzo 《Bollettino della Società italiana di biologia sperimentale》1984,60(10):1863-1869
The authors studied total and free circulating thyroid hormones, rT3, TBG and TSH behaviour on chronic liver disease in 11 subjects with cirrhosis of the liver with ascites(C.E.) and in 6 subjects with chronic active hepatitis (E.C.A.) in comparison with 15 healthy and euthyroid controls. Serum T3,FT3,T4 and FT4 levels were decreased significantly and serum rT3 values increased significantly both in the subjects with C.E. and in patients with E.C.A. Moreover no significantly changes of TSH and TBG levels has been found in 3 groups studied. These data suggest that the alteration of circulating thyroid hormones in chronic liver disease, may represent a compensatory way of reducing the patient's metabolic requirements. 相似文献
33.
Mario De Rosa Salvatore De Rosa Agata Gambacorta Maria Cartenì-Farina Vincenzo Zappia 《The Biochemical journal》1978,176(1):1-7
A spontaneous mutant of Escherichia coli (strain AB2847), selected for resistance to the aminoglycoside antibiotic neamine, shows severe restriction of amber suppressors in vivo. Ribosomes isolated from the mutant exhibit only low misreading in vitro in the presence of the antibiotic. Genetic and biochemical analyses indicate that the neamine-resistant phenotype is the result of two distinct mutations. The first, res3128, appears to affect the gene (strA) coding for the ribosomal protein S12. Although it leads to a restrictive phenotype it does not, however, confer resistance to streptomycin. The second mutation, X3128, is located between the sirA and AROB loci and is lethal when segregated from the res3128 mutation. It may affect the ribosome at the level of a post-translational modification. 相似文献
34.
Vincenzo Carelli Felice Liberatore Antonio Casini Rosanna Mondelli Alberto Arnone Italo Carelli Giuseppe Rotilio Irene Mavelli 《Bioorganic chemistry》1980,9(3):342-351
The composition and the structure of the product from the known electrochemical dimerization of the NAD+ have been conclusively demonstrated. A detailed analysis of the 1H and 13C nmr spectra has in fact led to the conclusion that the product contains three diastereoisomeric dimers of the 4,4′-tetrahydrobipyridyl type. Furthermore, the cytoplasmic fraction obtained from a standard mitochondrial preparation of rat liver has been shown to catalyze the oxygen uptake by the dimers. A 1 : 1 molar ratio of the reagents in the redox process is indicated by manometric data on oxygen uptake complemented by spectrophotometric analysis of the oxidized substrates, suggesting that H2O2 is the reduction product. NAD+ was identified as the oxidation product by an enzymatic method. 相似文献
35.
Ettore Benedetti Benedetto Di Blasio Vincenzo Pavone Carlo Pedone Claudio Toniolo Gian Maria Bonora 《International journal of biological macromolecules》1980,2(4):217-224
The X-ray diffraction and i.r. absorption conformational analysis of has showed the absence of intramolecularly hydrogen-bonded peptide conformations in the solid state. The molecules are held together in rows of ‘cyclic dimer’ motifs through intermolecular NH … OC (acid) and OH … OC {urethane} hydrogen bonds, the secondary amide-like group of the urethane moiety being in the unusual cis conformation, whereas the carboxylic acid group in the common syn conformation. The two molecules in the unit cell present a centrosymmetric set of ?, ψ1, and ψ2 values. In polar solvents solvated species largely predominate. In saturated hydrocarbon solution non-associated and associated (mostly involving the carboxylic acid CO as the proton acceptor) species simultaneously occur. The extent of association decreases with dilution. The amount of intramolecularly hydrogen-bonded oxy-C7 and C5 forms if any, should be extremely small. The type of association at saturation seems to differ from that found in the crystalline compound obtained by precipitation with saturated aliphatic hydrocarbons (from a diethyl ether solution). 相似文献
36.
Champa Sengupta Vincenzo Deluca David S. Bailey Desh Pal S. Verma 《Plant molecular biology》1981,1(1):19-34
The synthesis and processing of the major storage proteins in soybean cotyledons was studied both in vivo and in vitro. The and subunits of 7S as well as the 11S proteins are synthesized as higher molecular weight-precursors on membrane-bound polysomes. The initial translation products of the 7S are proteolytically cleaved during translation suggesting the removal of a signal peptide as evidenced by the presence of 2 and 2 peptides immunoreactive with 7S antibody in the in vitro chain completion products of the membrane-bound polysomes. This is followed or accompanied by cotranslational glycosylation, which increases their size equivalent to that of initially-synthesized precursors. In vivo pulse-labelled 7S and products are of slightly higher molecular weights than the immunoprecipitable chain-completion products, indicating further post-translational modifications. A slow post-translational processing during a period of 1.5 to 16 h yields the final 7S and glycoproteins.Acidic and basic subunits of the 11S protein appear to be synthesized from common large molecular weight (60K-59K) precursors. Antibodies to the 11S acidic component recognize both acidic and basic domains in the precursor while those raised against basic subunits appear to be specific for that region only. The processing of the 11S precursor is also very slow and occurs post-translationally. This slow rate of processing, coupled with a temporal difference in the synthesis of 7S and 11S components, suggests a highly coordinated mechanism for synthesis and packaging of these proteins into protein bodies during seed development. 相似文献
37.
Natale Cascinelli Gian Paolo Balzarini Vincenzo Fontana Sergio Orefice Umberto Veronesi 《Cancer immunology, immunotherapy : CII》1977,2(3):157-161
Summary From November 1973 to December 1974, 20 patients with advanced malignant melanoma were treated with BCG given by intralymphatic route at the Cancer Institute of Milan. The lyophilized Pasteur BCG was used. Patients were treated with a single dose ranging from 0.2–80 mg. Patients' performance status was never severely impaired.The most frequent side effects were fever, lymphangitis, and lymph node enlargement.Variations were observed in white cell count, ERS and immunoglobulins; in no case did we find evidence of liver toxicity or tumor growth enhancement. It is concluded that the intralymphatic route is a safe way of administrating BCG. 相似文献
38.
D Cavallini G Ricci S Duprè L Pecci M Costa R M Matarese B Pensa A Antonucci S P Solinas M Fontana 《European journal of biochemistry》1991,202(2):217-223
Aminoethylcysteine, lanthionine, cystathionine and cystine are mono-deaminated either by L-amino-acid oxidase or by a transaminase exhibiting the properties described for glutamine transaminase. The deaminated products cyclize producing the respective ketimines. Authentic samples of each ketimine were prepared by reacting the appropriate aminothiol compound with bromopyruvate, except cystine ketimine which required the interaction of thiopyruvate with cystine sulfoxide. Reduction of the first three mentioned ketimines with NaBH4 yields the respective derivatives with the saturated rings of thiomorpholine and hexahydrothiazepine. The same reduction is carried out enzymically by a reductase extracted from mammalian tissues. Properties of the members of this family of compounds are described. Gas chromatography followed by mass spectrometry permits the identification of most of these products. HPLC is very useful for the determination of the ketimines by taking advantage of specific absorbance at 380 nm obtained by prior derivatization with phenylisothiocyanate. Adaptation of these and other analytical procedures to biological samples disclosed the presence of most of these compounds in bovine brain and in human urine. By using [35S]lanthionine ketimine as a representative member of the ketimine group, the specific, high-affinity, saturable and reversible binding to bovine brain membranes has been demonstrated. The binding is removed by aminoethylcysteine ketimine and by cystathionine ketimine indicating the occurrence in bovine brain of a common binding site for ketimines. The reduced ketimines are totally ineffective in competing with [35S]lanthionine ketimine. Alltogether these findings are highly indicative for the existence in mammals of a novel class of endogenous sulfur-containing cyclic products provided with a possible neurochemical function to be investigated further. 相似文献
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