Other Dd Strategies And Improvements To The Assay

Another strategy to provide RNA fingerprints employed an arbitrary primer instead of an anchored oligo-dT primer in the first step of RT, selecting those regions internal to the RNA that have 6-8 base matches with the 3' end of the primer. As in DD-PCR, this is followed by arbitrary priming of the resulting first strand of cDNA with the same or a different arbitrary primer, and then PCR amplification. This method is known as RAP-PCR.[14] This method samples anywhere in the RNA, including opening reading frames, and can be used on RNAs that are not poly-adenylated (such as bacterial RNA). A limitation of this method too is that rare RNAs will be underrepresented.[1] Differential display strategies designed to target specific sequences in bacteria, such as highly iterated palindromic (HIP) elements found in half of the genes in the genome of cyanobacteria, provided a convenient global expression strategy for identifying light intensity-regulated genes in bacteria using a limited number of primers.[15] Another area of wide application of DD is a study of scarcely sequenced and complex plant genes, which contain large families of homologous genes.[16]

In order to improve the specificity of DD, attempts were made to replace the 10-13-base arbitrary primers— which hybridize nonspecifically to cDNA templates causing mismatches—with primer sites produced by restriction enzyme digests of double-stranded (ds) cDNAs; thus allowing adapters for priming sites to be ligated into specific regions on the cDNA. These ds cDNAs are then amplified with either anchored oligo-dT

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Getting Started With Dumbbells

Getting Started With Dumbbells

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.

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