Kava and passionflower have long been used in traditional medicine for their calming properties, and the herbs are now sold in stores as capsules or liquid extracts.

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The group infused a plastic-like polymer with microscopic capsules containing a liquid healing agent.

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"Patients can speak to their pharmacist about the option of having the pharmacy compound Tamiflu capsules into a liquid, " DeAngelis said in an e-mail.

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The herb is available as dried leaves and flowers, a concentrated liquid or tincture extract, in capsules and ointment and prepared tea.

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Capsugel manufactures a variety of capsules (hard gelatin, liquid-filled and vegetarian to name a few) used by pharmaceutical and nutrition companies.

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The leaves are dried and powdered and sold in a few different forms, typically in capsules, tablets, powder, or as a liquid.

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That is because electronic paper does not need backlighting in the way that liquid-crystal displays do (see article) and making beads or capsules change colour does not take much energy.

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It is available in capsules and tablets, as well as bedtime teas and a tincture, a liquid you can put under your tongue or mix with water.

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