�Ͼ�ҽ�ƴ�ѧ��һ����ҽԺƤ���� 210029

�ֲ�Ӧ�÷�ɹ˪Խ��Խ�����ڽ���.�󲿷ֵķ�ɹ˪�������ɹ���ͻ�ѧ��ɹ�����,������Ч�ط�ֹ�����������Ƥ����߷�Ӧ���������ơ����ϻ��Լ�Ƥ�����ķ���.��ɹ˪Ӧ���в������ߺͳ��������ߵ�ȫ���������.���۷�ɹ˪Ҫ�������չ���,˥��ϵ��,�в������߷��������Լ����������߷������ܵȷ�����п���.

Department of Dermatology, First Affiliated Hospital of Naniing Medical Llnivcrsity, Nanjing 210029, China

Topical sunscreens act by absorbing or scattering ultraviolet(UV) radiation and are widely available for general public use as a consumer product.Most sunscreens combine chemical UV absorbing sunscreens and physical inorganic sunscreens.Promoting sunscreen use is an integral part of prevention aiming at reducing UV radiation-induced sunburn,immunosuppression,photoaging and skin cancers.Protection against both ultraviolet B(UVB)and ultraviolet A(UVA)radiation is desirable.To assess a sunscreen,absorption spectrum,reduction coefficient,ability of UVB- and UVA-protection should be considered.