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Bronchiectasis, for which once only the most elementary palliation could be offered, now often can be cured by operation or well controlled by conservative therapy. Since true bronchiectasis implies irreversible anatomic changes, operation offers the only hope of cure, and it should be undertaken whenever it is not contraindicated by extent of involvement, age of the patient or other factors. Surgical results are excellent and mortality is at a minimum. When operation is prohibited, good results can still be anticipated by conservative measures. Such conservative therapy should combine prolonged use of antimicrobial drugs with adequate drainage of the diseased segments and general supportive measures. Any residual infection can be controlled by moderate use of appropriate antimicrobial agents. It is emphasized, however, that the control of bronchiectasis requires very careful diagnostic studies and a detailed analysis of the patient's condition, and that the therapy itself must be carefully adjusted in terms of the individual situation. 相似文献
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CATHERINE ROZARIO LOÏC MORIN REW J. ROGER MICHAEL W. SMITH MIKLÓS MÜLLER 《The Journal of eukaryotic microbiology》1996,43(4):330-340
ABSTRACT. Complete nucleotide sequences have been established for two genes (gap1 and gap2) coding for glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12) homologs in the diplomonad Giardia lamblia. In addition, almost complete sequences of the GAPDH open reading frames were obtained from PCR products for two free-living diplomonad species, Trepomonas agilis and Hexamita inflata, and a parasite of Atlantic salmon, an as yet unnamed species with morphological affinities to Spironucleus. Giardia lamblia gap 1 and the genes from the three other diplomonad species show high similarity to each other and to other glycolytic GAPDH genes. All amino-acyl residues known to be highly conserved in this enzyme are also conserved in these sequences. Giardia lamblia gap2 gene is more divergent and its putative translation reveals the presence of a cysteine and serine-rich insertion resembling a metal binding finger. This motif has not yet been noted in other GAPDH molecules. All sequences contain an S-loop signature with characteristics close to those of eukaryotes. In phylogenetic reconstructions based on the derived amino acid sequences with neighborjoining, parsimony and maximum-likelihood methods the four typical GAPDH sequences of diplomonads cluster into a single clade. Within this clade, G. lamblia gap1 shares a common ancestor with the rest of the genes. The latter are more closely related to each other, indicating an early separation of the lineage leading to the genus Giardia from the lineage encompassing the morphologically less differentiated genera, Trepomonas, Hexamita and that of the unnamed species. This result is discordant with the orthogonal evolution of diplomonads suggested on the basis of comparative morphology. In neighbor-joining reconstructions G. lamblia gap2 occupies a variable position, due to its great divergence. In parsimony and maximum likelihood analysis however, it shares a most recent common ancestor with the typical G. lamblia gap1 gene, suggesting that it diverged after the separation of the Giardia lineage. The position of the diplomonad clade in broader phylogenetic reconstructions is firmly within the typical cytosolic glycolytic representatives of GAPDH of eukaryotes. 相似文献
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