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Thirty-one patients who received a prolonged maintenance therapy with cordarone to treat and prevent cardiac arrhythmias underwent an ophthalmologic examination. The treatment lasted 1.5 to 51 months. The signs of keratopathy were detected in 24 (77.4%) patients using a slit lamp biomicroscopy. There is a relationship between the severity of keratopathy and a daily dose of cordarone: in most cases signs of stage I keratopathy were detectable when the daily dose was up to 200 mg. Keratopathy appears to be reversible after the drug has been discontinued. 相似文献
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A. Y. Aleksenko N. A. Makarova I. V. Nikolaev A. J. Clutterbuck 《Current genetics》1995,28(5):474-477
A wild isolate of Penicillium canescens was subjected to mutagenesis, and 150 chlorate-resistant mutants were isolated and classified in respect of their ability to utilize various nitrogen sources. Strains supposedly deficient in nitrate reductase have been transformed with the nitrate-reductase gene from Aspergillus niger. Transformation probably occurred by non-homologous integration of the transforming vector into the chromosome. Co-transformation with the AMA1 replicating element from A. nidulans enhanced transformation frequency up to 2000-fold, and was shown to result in autonomous maintenance of replicating concatenates, one of which was re-isolated by transformation of E. coli. 相似文献
5.
Kaverin NV Matrosovich MN Gambaryan AS Rudneva IA Shilov AA Varich NL Makarova NV Kropotkina EA Sinitsin BV 《Virus research》2000,66(2):123-129
In our previous studies influenza A virus reassortants having neuraminidase (NA) gene of A/USSR/90/77 (H1N1) strain and hemagglutinin (HA) genes of H3, H4 and H13 subtypes were shown to produce a low virus yield and to exhibit a strong tendency to virion aggregation. More detailed studies with the use of a H3N1 reassortant and its high-yield non-aggregating variants revealed that NA of A/USSR/90/77 strain is inefficient in the removal of the terminal sialic acid residues from the virion components, and that the inefficiency of NA may be compensated by mutations in HA gene leading to a decrease of the receptor-binding affinity (Kaverin, N.V. , Gambaryan, A.S., Bovin, N.V., Rudneva, I.A., Shilov, A.A., Khodova, O.M., Varich, N.L., Sinitsin, B.V., Makarova, N.L., Kaverin, N.V., 1998. Postreassortment changes in influenza virus hemagglutinin restoring HA-NA functional match, Virology 244, 315-321). The present report describes studies performed with the use of H2N1 and H4N1 reassortants having HA genes of A/Pintail/Primorie/695/76 (H2N3) and A/Duck/Czechoslovakia/56 (H4N6) strains respectively and NA gene of A/USSR/90/77 strain. The low-yield reassortants and their high-yield non-aggregating variants were studied in both direct and competitive binding assays with sialic acid-containing substrates. The non-aggregating variants were shown to have a decreased affinity as compared to the initial reassortants toward high-molecular-weight sialic acid-containing substrates. The sequencing of HA genes revealed that all non-aggregating variants of H2N1 and H4N1 reassortants had amino acid substitutions increasing the negative charge of the HA molecule in the vicinity of the receptor-binding pocket. The results suggest that the influenza virus reassortants containing low-functional NA undergo similar postreassortment changes irrespective of the HA subtype: their receptor-binding activity decreased due to negatively charged amino acid substitutions in the vicinity of the receptor-binding pocket. 相似文献
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Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon 总被引:1,自引:1,他引:1
We have examined whether dietary polyamines influence the formation and
initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in
rat colon. Effects of a combination of dietary polyamines at three dose
levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g;
spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied
in animals in two different experimental situations: animals treated with
AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a
specific inhibitor of endogenous polyamine synthesis. In both experimental
situations, dietary polyamines enhanced the growth of ACF, expressed as the
number of large ACF (foci with three or more aberrant crypts, ACF > or =
3), whereas the formation of ACF, expressed as the number of ACF, was
apparently not altered. In animals treated with AOM alone, maximal growth
enhancing effect on ACF was nearly obtained with the median level of
dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO
reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of
DFMO was counteracted by dietary polyamines in a dose- dependent manner,
and it was abolished at the highest level of polyamines. In conclusion, it
was demonstrated that dietary polyamines are able to enhance the growth of
AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused
inhibition of ACF growth, probably by compensating for the DFMO-reduced
endogenous polyamine synthesis.
相似文献
8.
Liaturinskaia OV Gerasimenko IuP Makarova MA Berdiaeva IN 《Klinichna khirurhiia / Ministerstvo okhorony zdorov'ia Ukra?ny, Naukove tovarystvo khirurhiv Ukra?ny》2000,(10):44-45
In 1994-1999 years in clinic 19 children with omphalocele were treated, 8 of them died. Authors proposed tactic of treatment of their own, giving preference to conservative method, what permitted to reduce mortality of children with embryonal hernia. 相似文献
9.
Global profiling of Shewanella oneidensis MR-1: expression of hypothetical genes and improved functional annotations 总被引:1,自引:0,他引:1 下载免费PDF全文
Kolker E Picone AF Galperin MY Romine MF Higdon R Makarova KS Kolker N Anderson GA Qiu X Auberry KJ Babnigg G Beliaev AS Edlefsen P Elias DA Gorby YA Holzman T Klappenbach JA Konstantinidis KT Land ML Lipton MS McCue LA Monroe M Pasa-Tolic L Pinchuk G Purvine S Serres MH Tsapin S Zakrajsek BA Zhu W Zhou J Larimer FW Lawrence CE Riley M Collart FR Yates JR Smith RD Giometti CS Nealson KH Fredrickson JK Tiedje JM 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(6):2099-2104
10.
Experiments on isolated functioning hearts of rats established that under equal filling pressure the hearts of the animals who are adapted to the periodic effect of hypoxy develop a higher force and rate of contractions; ultimately, the contractile function of such hearts, as calculated per unit of myocardial mass and unit of time, appears to be increased by 1/3. Oxygen consumption by the hearts of adapted animals does not much differ from the control values, and consequently, the efficiency of oxygen utilization increases approximately by 1/3. A considerable increase of adrenoreactivity of the hearts of adapted animals is also noted. The obtained data are discussed proceeding from the assumption that an increased power of the potassium pump in the sarcoplasmatic reticulum of the myocardium of adapted animals may influence the coupling of oxydation with phosphorillation in the mytochondria. 相似文献