Hepatitis C virus (HCV) is a small, enveloped Flavivirus with a positive strand ribonucleic acid (RNA) genome of approximately 9400 bases in length. The genome comprises one large open reading frame flanked by untranslated regions (UTRs), a highly conserved one at the 5' end, and another one which shows high heterogeneity at the 3' terminus. Substantial nucleotide sequence variations between various HCV isolates were found throughout the entire HCV genome. The genetic variation of HCV is thought to reflect sequence errors because of a nonproofreading RNA-dependent RNA polyme-rase. Many different but closely related HCV variants are thus generated within one HCV-infected individual called quasispecies.
considered as ''gold standard.'' This approach, however, is cumbersome and regarded as impractical for routine clinical laboratory settings. The 5'UTR region has been shown to be more convenient for genotyping in routine diagnostic laboratories. Moreover, this region is usually chosen as target sequence for detection of HCV RNA, thus allowing direct analysis of amplification products in a genotyping assay. The less conserved NS5B region, which contains a subtype-specific motif and which is standard for epidemiological applications, may also be chosen. For serological (ELISA-based) typing methods, type-specific antigenic properties of several epitopes encoded by the NS4 and core regions are used. The core and NS3 may offer additional possibilities for HCV genotyp-ing; however, their high variability renders the respective methods less sensitive, especially if only one probe/ subtype is used.
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The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.