doctor jobs
doctor jobs with http://www.doctors-onthenet.info

doctor jobs

Doctors On-the-Net

News for 10-Apr-18

Source: MedicineNet Kids Health General
Down Syndrome May Not Be Big Financial Burden on Families

Source: MedicineNet Kids Health General
Teen Violence Can Be Contagious, Study Contends

Source: MedicineNet Kids Health General
Baby Crib Ads Show Unsafe Practices, Study Says

Source: MedicineNet Kids Health General
Rest May Not Be Best for Kids After Concussion

Source: MedicineNet Kids Health General
Growth Charts

Source: MedicineNet Kids Health General
Health Tip: Help Toddlers Develop Stronger Hands

Source: MedicineNet Kids Health General
Teens May Not Heed Health Warnings on Cigars

Source: MedicineNet Kids Health General
Some Kids' Genes Might Make Food Ads More Tempting

Source: MedTerms Word of the Day
Epilepsy

Source: MedicineNet Kids Health General
Child Deaths Highlight Choking Dangers Posed by Grapes

Search the Web
doctor jobs
doctor of chiropractic
doctor patient
doctor recommended
doctor who
doctors
dr
eye doctor
animal doctor
ask the doctor

The Best doctor jobs website

All the doctor jobs information you need to know about is right here. Presented and researched by http://www.doctors-onthenet.info. We've searched the information super highway far and wide to provide you with the best doctor jobs site on the internet today. The links below will assist you in your efforts to find the information that you are looking for about
doctor jobs.

doctor jobs

Doctors on the net information
Need information for Doctors on the net? Our links will provide you with information on all type of types of Physicians over the internet .
Doctors on the net information

There are lots of places on the internet where you can buy doctor jobs but how can you be sure that when you purchase doctor jobs you are shopping in safety and that you will actually receive your purchase?

This is where we can help. We've sorted through all the possible places on the internet where you can buy doctor jobs and we've found the best. A place where you can get doctor jobs at a great price and be sure that you will get what you've paid for.

The following link will take you to the very best doctor jobs supplier we have found. Don't waste another moment searching, click and visit them now.

doctor jobs

Doctors on the net information
Need information for Doctors on the net? Our links will provide you with information on all type of types of Physicians over the internet .
Doctors on the net information

When you're looking for information on buying doctor jobs it can all seem very overwhelming. But don't worry, because we've sorted through all the doctor jobs sites on the internet and have found the very best ones that will get you what you want, how you want it.

We know how important it is to be informed when you're looking for doctor jobs. Some websites are better than others and will meet your doctor jobs needs in a better fashion.

Melanin: Aging of the Skin and Skin Cancer

 by: Diana Clarke

"Ultraviolet (UV) radiation is responsible for 90% of the visible signs of aging on the skin of whites," says Dr. Michael J. Martin, former Assistant Clinical Professor in the Dept. of Epidemiology and Biostatistics at University of California, San Francisco.

Blacks' skin, however, ages much slower.

Why are most dark-skinned blacks protected from harmful UV rays? Because compared to whites, blacks possess more melanin, the pigment that gives skin its color.

Melanin

Melanin offers protection against UV rays for blacks and other dark-skinned people. Conversely, fair-skinned people are much less protected and more susceptible to skin cancer. Furthermore, albinos' skin offers no protection.

Although blacks' skin produces more melanin than whites', all skin has the same number of melanocytes, the cells that manufacture the melanin.

Melanocytes manufacture melanin from an amino acid, tyrosin, with the help of an enzyme, tyrosinase. In the bottom layer of the epidermis above the dermis, UV light stimulates the production of melanin in the form of insoluble melanosomes. These surround the epidermal cells, which move up to the surface of the skin. The result is a tan.

Blacks' skin produce more melanin, even in the absence of sunlight, and their type of melanin, eumelanin, is more effective at blocking solar rays. However, white skin produces melanin only in the presence of sunlight and after the UV rays have penetrated the lower portion of the epidermis and have caused skin damage.

"Melanin also functions as an excellent free radical scavenger. It affects the delicately designed lipids that hold moisture in the stratum corneum (the outermost layer of the epidermis). If the skin loses its moisture, it becomes rigid and cracks," says Sergio Nacht, PhD., Senior Vice-President of Enhanced Derm Technologies, Inc. in Redwood City.

UV Radiation and Skin

UV-A has the longest wavelength, is not filtered by the ozone and passes through glass. It reaches the earth all year long and the amount is comparatively stable. It can penetrate the skin down to the dermis, beneath the four layers of epidermis. It is responsible for most of the visible signs of aging, due to damage to collagen and elastic fibers of the connective tissue of the dermis.

UV-A radiation also plays a role in the development of sunburns and skin cancer. Tanning salon lamps emit a large amount of UV-A rays to generate tans, so the American Academy of Dermatology does not recommend their use.

UV-B radiation, which is partially filtered by the ozone, penetrates the skin to the bottom layer of the epidermis where the basal cells are produced. UV-B can break the molecular bonds, disturbing the dividing cells and altering their structure. Compared with UV-A, UV-B is responsible for most of DNAs damage. It also causes most sunburns. During a sunburn the reddening of the skin, erythema, is caused by dilation of capillaries.

More UV-B is present during summer months between 10 a.m. and 4 p.m. and at latitudes closer to the equator. Furthermore, at high altitudes the air is thinner and cleaner, so UV-B radiation is more abundant.

UV-C, which is generally filtered by the ozone, has the shortest wavelength and the most energy, or intensity. It can sterilize hospital equipment and kill bacteria.

In addition, UV light that reaches the earth is scattered in all directions, and up to 85% is reflected from surfaces.

The Theory of Melanin for Environmental Adaptation

Originally, people of a particular race resided in a particular area. As time went on, their skin adapted to the environment. For instance, people who lived geographically close to the equator had darker skin, and people who lived far from the equator had lighter skin.

In Scotland, which lies at a northern latitude, descendants of the Britons have white skin. When their skin is exposed to the meager sunlight, the scant amount of melanin their skin produces is unable to block the sunlight. Therefore, their bodies are able to make Vitamin D with the help of sunlight. Vitamin D, a vitamin found in fish oil, is necessary to prevent rickets, a bone disease caused by too little calcium.

In contrast, in Africa, which is near the equator, blacks require intense sunlight to penetrate their dark skin to make Vitamin D. This is all well and good. However, when blacks lived in England during the Industrial Revolution, they were the first to develop symptoms of rickets, such as retarded growth, bowed legs and fractures because not enough sunlight was available.

Fortunately, in 1930, Vitamin D was discovered and dispensed as a supplement to add to the diet.

On the other hand, the skin of whites in Australia are in complete opposition to their climate. Consequently, intense UV radiation has been the major cause of skin damage and skin cancer Down Under.

About The Author

Diana Clarke is a teacher, freelance writer and founder of The Sun and Your Skin, a website on life and light at http://www.yourskinandsun.com.


dianaclarke2001@yahoo.com

Google

http://www.medmeet.com
Talk On The Net | MD Newscast | MD News | Go Meetings | Medical Presentations

Law Meet   MD Meetings   Medical Meetings On The Net