<span>A diseases may be classified as either communicable or non-communicable. Communicable diseases are caused by pathogens who inhabit a host, man (I'm not saying man is the only host or man is necessarily the final host; there could be many host) who in turn passes the disease to another. Pathogens are viral, bacterial, parasitic and fungal. There are several stages before the pathogen metamorphoses into a full-blown disease. The stages in which several events happen builds up before the pathogen affects the final host is called a communicable disease chain. There are six stages ( Pathogen, reservoir, portal of ext, mode of transmission, portal of entry and susceptible host) in the communicable disease chain but the step a nurse shouod take is
1. Destroy the second link (Reservoir) by thoroughly sanitizing the environment. Obviously, this is where the Pathogens live. If the reservoir is taken care of; there's no way they could infect the host.</span>
The factors are: The size of the sample, the extraction method, the method of purification and preservation of the DNA.
The quantity and quality of DNA can be greatly improved by performing PCR.
* Purification of nucleic acids is a key step for functional studies in biology. Because of the great diversity of living organisms in nature, purification becomes a real challenge for researchers, especially cell lysis.
The evolution of lysis methods has made it possible to improve efficiency, speed and simplicity. But, this lysis step remains a crucial step for the efficiency and the quality of the purification.
Answer: A. Zidovudine (Retrovir) and emtricitabine (Emtriva)
Explanation:
Basic postexposure prophylaxis (PEP) therapy typically includes treatment with one of these combinations of pharmacologic agents:
Zidovudine (Retrovir) and emtricitabine Emtriva),
Lamivudine (Epivir) and tenofovir (Viread), or
Tenofovir (Viread) and emtricitabine (Emtriva)
If the accidental exposure is especially severe, a third agent may be included.