The recommended starting dose of LIPITOR is 10 or 20 mg once daily. Patients who require a large reduction in LDL-C (more than 45%) may be started at 40 mg once daily.The dosage range of LIPITOR is 10 to 80 mg once daily.LIPITOR can be administered as a single dose at any time of the day, with or without food.The starting dose and maintenance doses of LIPITOR should be individualized according to patient characteristics such as goal of therapy and response (see current NCEP Guidelines).IPITOR can be administered as a single dose at any time of the day, with or without food. The starting dose and maintenance doses of LIPITOR should be individualized according to patient characteristics such as goal of therapy and response (see current NCEP Guidelines).
Cell Membranes. Cell membranes protect and organize cells. All cells have an outer plasma membrane that regulates not only what enters the cell, but also how much of any given substance comes in. Unlike prokaryotes, eukaryotic cells also possess internal membranes that encase their organelles and control the exchange of essential cell components.
The cell membrane's main trait is its selective permeability, which means that it allows some substances to cross it easily, but not others. Small molecules that are nonpolar (have no charge) can cross the membrane easily through diffusion, but ions (charged molecules) and larger molecules typically cannot. Nonpolar and small polar molecules can pass through the cell membrane, so they diffuse across it in response to concentration gradients. Carbon dioxide and oxygen are two molecules that undergo this simple diffusion through the membrane.