1. Article Avenue - free articles and downloads
They are caused by excessive secretion of oily substance called the sebum by sebaceous glands. Acne which is also known as acne vulgaris is an infection that happens when the sebaceous glands overwork and the hair follicles get clo Submitted by.
http://articleavenue.com/

2. Mortality Detail Files, 1968-1991 -- Icpsr Front Page
Both the ICD and the ICDA use identical three digit codes for the disease categories, and these three digit classifications are listed in the appendix. The codes used in these classifications take the form of NNN.n, where "NNN" is the disease...
http://www.icpsr.umich.edu/cocoon/DDI/OSIRIS/7632-78.xml

3. Acne - Drugs & Vitamins - Drug Library - DrugDigest -- Drugdigest
Diseases of the Sebaceous Glands. Blackheads result when sebum (oil) and skin cells become clogged in the sebaceous hair follicle. Whiteheads result when the sebaceous follicle is completely clogged with sebum and skin cells.
http://www.drugdigest.org/DD/PrintablePages/HealthConditions/1,20041,550226,00....