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НазваMedicinal plants (реферат)
РозділІноземна мова, реферати англійською, німецькою
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Medicinal plants

Herbalism, also known as phytotherapy, is folk and traditional
medicinalpractice based on the use of plantsand plant extracts. 

Finding healing powers in plants is an ancient idea. People in all
continents have long used hundreds, if not thousands, of indigenous
plants, for treatment of various ailments dating back to prehistory.
There is evidence that Neanderthals living 60,000 years ago in
present-day Iraq used plants for medicinal purposes. These plants are
still widely used in ethnomedicine around the world. 

Plants have an almost limitless ability to synthesize aromatic
substances, most of which are phenols or their oxygen-substituted
derivatives such as tannins. Most are secondary metabolites, of which at
least 12,000 have been isolated, a number estimated to be less than 10%
of the total. In many cases, these substances serve as plant defense
mechanisms against predation by microorganisms, insects, and herbivores.
Many of the herbs and spices used by humans to season food yield useful
medicinal compounds. 

The use and search for drugs and dietary supplements derived from plants
have accelerated in recent years. Pharmacologists, microbiologists,
botanists, and natural-products chemists are combing the Earth for
phytochemicals and leads that could be developed for treatment of
various diseases.--Dr M Tariq Salman 19:06, 30 January 2006 (UTC) 

The use of herbsto treat diseaseis almost universal among
non-industrialized societies. A number of traditions came to dominate
the practise of herbal medicine in the Western worldat the end of the
twentieth century: 

The Western, based on Greekand Romansources, 

The Ayurvedicfrom India, and 

Chinese herbal medicine(Chinese herbology). 

Many of the pharmaceuticalscurrently available to Western physicians
have a long history of use as herbal remedies, including opium, aspirin,
digitalis, and quinine. 

Biological background

All plants produce chemical compoundsas part of their normal
metabolicactivities. These can be split into primary metabolites, such
as sugarsand fats, found in all plants, and secondary metabolites found
in a smaller range of plants, some only in a particular genusor species.

The autologousfunctions of secondary metabolites are varied. For
example, as toxinsto deter predation, or to attract insects for
pollination. It is these secondary metabolites which can have
therapeutic actions in humans and which can be refined to produce drugs.
Some examples are inulinfrom the roots of dahlias, quininefrom the
cinchona, morphineand codeinefrom the poppy, and digoxinfrom the

As of 2004, the National Center for Complementary and Alternative
Medicine started to fund clinical trialsinto the effectiveness of herbal

Some surveys of scientific herbal medicine can be found in
Evidence-based herbal medicine edited by Michael Rotblatt, Irwin Ziment;
Philadelphia: Hanley & Belfus, 2002, and Herbal and traditional
medicine: molecular aspects of health, edited by Lester Packer, Choon
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