Molecular biology-based assays are invaluable tools for the management of chronic viral hepatitis. Assays employing target—namely, polymerase chain reaction (PCR) and nucleic acid sequence-based amplification (NASBA, TMA)—or signal amplification techniques— branched chain signal amplification (bDNA) and the hybrid capture system (HCS)—are now commercially available for the quantification of viral burden in infected patients (Table 1). Different assays have different sensitivities and ranges of linearity. More recently, ''realtime'' PCR techniques have been developed. The principle is to detect amplicon synthesis and to deduce the amount of viral genomes in the starting clinical samples during, rather than at, the end of the PCR reaction. These methods are theoretically more sensitive than classical target amplification techniques and are not prone to carryover contamination. Their dynamic range of quantification is consistently wider, making them particularly useful for quantifying the full range of viral loads observed in untreated and treated patients.
Whatever the technique used, software is used to calculate the threshold cycle (CT in ABI Prism, Cp in LightCycler) in each reaction with which there is a linear relationship with the initial amount of DNA. In each run, parallel processing of a panel of quantified standards is used to establish a standard curve for quantification (for further review, see Ref. ).
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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.