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Biomedical subjects

R Mercier

Publications and source records attributed to R Mercier.

At least 37 records · Page 2Linked to original sources
PubMed1981

Codon catalog usage is a genome strategy modulated for gene expressivity.

The nucleic acid sequence bank now contains 161 mRNAs, 43 new genes are added. One sequence, that of B. mori fibroin, is dropped due to uncertainty on the starting point for translation. Frequencies of all codons are given for each gene added and for each genome type in the total bank. A new series of correspondence analyses on codon use is presented, substantiating the genome hypothesis. Internal regulation of mRNA expression by different third base choices between quartet and duet codons is proposed for bacterial genes.

Amino Acid Sequence↗
PubMed1980

Codon catalog usage and the genome hypothesis.

Frequencies for each of the 61 amino acid codons have been determined in every published mRNA sequence of 50 or more codons. The frequencies are shown for each kind of genome and for each individual gene. A surprising consistency of choices exists among genes of the same or similar genomes. Thus each genome, or kind of genome, appears to possess a "system" for choosing between codons. Frameshift genes, however, have widely different choice strategies from normal genes. Our work indicates that the main factors distinguishing between mRNA sequences relate to choices among degenerate bases. These systematic third base choices can therefore be used to establish a new kind of genetic distance, which reflects differences in coding strategy. The choice patterns we find seem compatible with the idea that the genome and not the individual gene is the unit of selection. Each gene in a genome tends to conform to its species' usage of the codon catalog; this is our genome hypothesis.

Animals↗
PubMed1978

[Instrumental technics of exploration of the mediastinum].

Several techniques can be used for the diagnosing of diseases pertaining to the mediastinum. The diagnosis can be made in 78% of cases by mediastinoscopy. When the lesion is situated beyond the reach of mediastinoscopy, needle biopsy and pleuroscopy can be used either alone or associated to mediastinoscopy. The histological diagnosis can be made in almost all cases. But a few precautions are necessary because this technique carries a certain risk for vessels. Therefore preoperative angiography of the superior vena cava or arteriography of the branches of the aortic arch should be performed to help for the diagnosis and ensure its safety.

Biopsy, Needle↗
PubMed1978

[Role of surgery in the treatment of deep venous thrombosis of the lower limbs and prevention of pulmonary embolism].

Besides anticoagulants and thrombolytic drugs, surgery should be included among the therapeutical means to prevent deep phlebitis of the lower limbs. Early phlebography, thoroughly innocuous, is necessary to any coherent therapy. The prevention of pulmonary embolism which can be done by a ligature of the inferior vena cava or by the fitting of an umbrella-shaped filtre, is performed most of the time with a clamp of Adams and de Weese. Its reliability is satisfactory as the percentage of embolic recurrences does not exceed 5%. Early venous thrombectomy prevents in 60 to 80% of cases the post-phlebitic incidents; but its indication must be reserved to young patients.

Humans↗