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21.

Background  

Tuberculosis (TB) is a major health problem and HIV is the major cause of the increase in TB. Sub-Saharan Africa is endemic for both TB and HIV infection. Determination of the prevalence of M. tuberculosis strains and their drug susceptibility is important for TB control.  相似文献   
22.

Background  

Heterologous prime-boost immunization protocols using different gene expression systems have proven to be successful tools in protecting against various diseases in experimental animal models. The main reason for using this approach is to exploit the ability of expression cassettes to prime or boost the immune system in different ways during vaccination procedures. The purpose of the project was to study the ability of recombinant vaccinia virus (VV) and bacterial plasmid, both carrying the NS1 gene from tick-borne encephalitis (TBE) virus under the control of different promoters, to protect mice against lethal challenge using a heterologous prime-boost vaccination protocol.  相似文献   
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The synthesis of phosphoramidite reagents and solid-phase supports based on hydroxyprolinol for the introduction of the residues of biotin, lipoic acid, amino groups, and terminal acetylene groups at different positions of the oligonucleotide chain has been described. The efficiency of the reagents and supports has been confirmed by the synthesis of the corresponding modified oligonucleotides.  相似文献   
25.
The substrate specificity of recombinant full-length diguanylate cyclase (DGC) of Thermotoga maritima with mutant allosteric site was investigated. It has been originally shown that the enzyme could use GTP closest analogues – 2′-deoxyguanosine-5′-triphosphate (dGTP) and 9-β-D-arabinofuranosyl-guanine-5′-triphosphate (araGTP) as the substrates. The first demonstrations of an enzymatic synthesis of bis-(3′-5′)-cyclic dimeric deoxyguanosine monophosphate (c-di-dGMP) and the previously unknown bis-(3′-5′)-cyclic dimeric araguanosine monophosphate (c-di-araGMP) using DGC of T. maritima in the form of inclusion bodies have been provided.  相似文献   
26.

Background  

Some diseases, like tumors, can be related to chromosomal aberrations, leading to changes of DNA copy number. The copy number of an aberrant genome can be represented as a piecewise constant function, since it can exhibit regions of deletions or gains. Instead, in a healthy cell the copy number is two because we inherit one copy of each chromosome from each our parents.  相似文献   
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The Perccottus glenii is one of the most invasive of European fish species. During August-September 2019, we examined Chinese sleeper from six waterbodies in Latvia and Ukraine for parasites. Seventeen parasite species were registered, including two ciliate species, one coccidia, one monogenean, one cestode, six trematodes, three nematodes, one acanthocephalan, one parasitic copepod, and one bivalve glochidia. Maximum species richness was registered in Ukraine, with eight species at Vylkove and three species at Lake Kartal. Numbers in Latvia were generally lower with three species at Ilgas and just one at Gailezers. The parasite fauna registered in Latvia was poor overall, the richest site being the University pond. Two non-native parasite species were registered, the monogenean Gyrodactylus perccotti and the copepod Neoergasilus japonicus. Gyrodactylus perccotti was observed in Lake Kartal and the Danube delta in Ukraine, but not in Latvia, while N. japonicus only occurred in the University Pond in Latvia. This is the first record of this species in Latvia. Low parasite acquisition by the Chinese sleeper in Latvia may be caused by the release of this fish from aquaria, which is commonly registered in the region. It is likely that such low parasite loads have contributed to the formation of stable populations and the subsequent increase in expansion.  相似文献   
29.
This study provides a comprehensive checklist of parasites reported for native and non-native populations of seven Ponto-Caspian goby species, i.e. Babka gymnotrachelus, Neogobius fluviatilis, N. melanostomus, Ponticola gorlap, P. kessleri, Proterorhinus semilunaris and P. semipellucidus, all of which have recently expanded their natural range, either by transoceanic translocation or along the three main European intracontinental invasion corridors. In some cases, invasion success is facilitated by loss of natural enemies, such as predators and parasites; thus, knowledge of a species natural parasite fauna is essential for assessments of enemy release in the host's non-native range. The study is based on published literature and personal unpublished data related to parasites of Ponto-Caspian gobiids. A total of 249 parasite taxa have been reported during 1931—2019, with higher numbers reported from native (214) than non-native (151) ranges. This checklist indicates apparent reduction in native parasites in non-native ranges in all goby species, although parasite colonisation in non-native ranges differs between fish species and invasion corridors. Interestingly, the cumulative number of species reported is still gradually increasing in both ranges. Acquisition of high number of local parasite species also indicates competence of Ponto-Caspian gobies to a wide range of generalist parasites.  相似文献   
30.
This article reports on the optical properties of 0.5% mol of Sm3+, Dy3+ ion‐doped B2O3‐TeO2‐Li2O‐AlF3 (LiAlFBT) glasses. The glass samples were characterized by optical absorption and emission spectra. Judd‐Ofelt theory was applied to analyze the optical absorption spectra and calculate the intensity parameters and radiative properties of the emission transitions. The emission spectra of Sm3+ and Dy3+:LiAlFBT glasses showed a bright reddish‐orange emission at 598 nm (4G5/26H7/2) and an intense yellow emission at 574 nm (4F9/26H13/2), respectively. Full width at half maximum (FWHM), stimulated emission cross section, gain bandwidth and optical gain values were also calculated to extend the applications of the Sm3+ and Dy3+:LiAlFBT glasses. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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