bands that differ in size between different strains. Thus the name restriction fragment length polymorphism (RFLP) refers to this polymorphic nature of the locations of restriction enzyme sites within defined genetic regions. Only the genomic DNA fragments that hybridize to the probes are visible in RFLP analysis, which greatly simplifies the analysis. Different types of nucleic acid probes can be used for typing: 1) genes encoding metabolic, virulence or resistance functions; 2) multicopy elements, including insertion sequences (IS) and transposons. Insertion sequences typing technique using insertion sequences as a probe are in general very reproducible and can provide a highly discriminating typing tool. Discrimination is related to the presence of multiple copies of these elements at diverse locations in the chromosome. However, RFLP is a slow and labor-intensive technique requiring specialized equipment and expertise. Besides, careful selection and optimization of probe sequence, restriction endonucleases, electrophoresis, and hybridization conditions need to be developed for each species or pathovar to be typed. Furthermore, large-scale application of RFLP analysis requires international standardization of the technique, reagents, type strains, and nomenclature. In the field of Mycobacterium tuberculosis this was established by several public health reference laboratories for IS6110 RFLP-fingerprinting, which integrates standard computer analysis of patterns and a common database, and it is now widely applied for large-scale surveillance of tuberculosis.[3]

Restricted DNA

After endonuclease treatment


Electrophoresis marker

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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