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SAIDUL ISLAM, KAUSHAL K.
CHANDRUL, GAURAV KUMAR
SHARMA, RISHI KUMAR JOSHI
DEPARTMENT OF PHARMACY,
MEWAR UNIVERSITY,
CHITTORGARH, INDIA.
ABSTRACT: Skin is the outer
covering of the body.in humans, it is
the largest organ of the integumentary
system. Human skin is consisting of
mainly three layer- Epidermis, dermis
and subcutaneous fatty tissue. In skin
there is a cell which is called as
“melanocytes”. The melanocytes cell
is responsible for melanin production
and this melanin is responsible for
determining skin and hair color.
Melanin is produced by oxidation of
the amino acid tyrosine, followed by
polymerization. Generally those with
darker skin tones and more melanin
are able to tolerate exposure to the sun
for hours without getting sunburn. “A
deficiency in melanin can lead to
several disorders and disease. For
example, a complete absence of
melanin cause a condition called
Albinism”.
KEYWORDS: Skin color, layers of
skin, types of skin, skin evaluation,
skin sensitivity, melanin and its types,
effect of melanin on skin, importance
of melanin, dark skin light skin, UV
rays and skin , How to reduce
melanin, action of an cream on skin ,
chemicals and whitening agents used
in skin cream.
INTRODUCTION TO SKIN:
Human skin is considered to be the
largest organ of the body. The surface
area of the skin on an average adult is
1.8m2 and represents 16% of the total
body weight. Thethickness of the skin
varies throughoutthe body. It depends
on how much use we make of that
area. For example, because we use
our feet for walking, it is thickest on
the soles our feet. We use our hands
for doing many everyday tasks such
as picking up and writing, so it is also
thick on our palms. The skin is a
multifunctional organ. Is is divided
into three main layers- The dermis,
epidermis and subcutaneous. The
image shows a microscopic cross –
section of human skin.
Figure-1
What does skin do in our body?Skin
do thermoregulation in our body. The
skin helps us to maintain our body
temperature. When we are hot, there
is vasodilation at the skin surface.
This cools us down by allowing more
heat to escape. Skin do metabolism in
our body. When we are hot or
exercising, sweat glands in our skin
excrete water salts and proteins. Apart
of this, skin does sensation, protection
and synthesis of vitamin D in our
body. [Rf-1]
LAYERS OF SKIN: Skin has three
layers mainly these are-
A. THE EPIDERMIS:- The
epidermis is the outermost layer
of the skin. Its composed of
epithelial tissue. The epidermis
has no blood supply and is
nourished by diffused oxygen
from surrounding air. The
thickness of epidermis is
approximately 0.1 mm. It acts
as protective barrier by
preventing pathogens from
entering.
The epidermis is sub divided
into 5 layers-
1. STRATUM CORNEUM:
the outermost layer of the
epidermis. There are many
cells which are tightly
packed together. This allows
the skin to be tough and
waterproof. This layer is
important in the prevention
of invasion from foreign
things, such as bugs and
bacteria.
2. STRATUM LUCIDUM:
this layer contains several
clear and flat dead cells. It is
a tough layer and is found in
thickened skin including the
palms of the hand and soles
of the feet.
3. STRATUM
GRANULOSUM: The
stratum granulosum is
composed of 3 to 4 layers of
cells. Here keratin is formed
which is a colorless protein
important for skin strength.
4. STRATUM SPINOSUM:
This layer contains cells that
change shape from
columnar to polygonal.
Keratin also produced here.
5. STRATUM BASALE:
This layer is the deepest layer of
the epidermis, in which many
cells are active and dividing. The
stratum basale is separated from
the next layer-The Dermis-by a
basement membrane which is a
layer made of collagen and
proteins. [Rf1,2]
Figure-2
Cells of epidermis: This layer of
the skin consists of many special
cells including keratinocytes,
melanocytes, Markel cells and
Langerhans cells. Keratinocytes
are cells that make a special fat
which gives skin its waterproof
properties. Melanocytes produce
melanin, which is a pigment
giving us the color of our skin.
The Markel cells which
functions as a receptor and is
responsible for stimulating
sensory nerves and the
Langerhans cell is defined as
inter-aspersed among the
keratinocytes of this layer is a
type of denofritic cell called the
Langerhans cell which function
as a macro phase by engulfing
bacteria, foreign particles and
damaged cells that occur in this
layer. [Rf-3]
Figure-3
B. THE DERMIS: The dermis is
the second layer of the skin.
The dermis varies in thickness,
ranging from 0.6mm on the
eyelids to 3mm on the back,
palms and soles. Its –
- Flexible and strong
connective tissue.
- Elastic, reticular and
collagen fibers.
- Cells: Fibroblasts, macro
phases (WBC), mast cell
(histamine)
- Nerve, blood and lymphatic
vessels.
- Oil and sweat glands
originate and hair follicles.
The dermis is made of two
layers of connective tissue,
these are- 1 Papillary layer and
2 Reticular layer. [Rf- 4,3]
Figure-4
C. HYPODERMIS: The
hypodermis (also called the
subcutaneous layer or
superficial fascia) is a layer
directly below the dermis and
serve to connect the skin to the
underlying fascia (fibrous
tissue) of the bones and
muscles. It is not strictly a part
of the skin, although the border
between the hypodermis and
dermis can be difficult to
distinguish. The hypodermis
consists of well Vascularized,
loose, areolar connective tissue
and adipose tissue , which
functions as a mode of fat
storage and provides insulation
and cushioning for the
integument. [Rf-3,5]
Figure-5
Type of skin:-There are four
basic type of skin- Normal, dry,
oily and combination skin. Skin
type is determined by genetics.
The condition of our skin can
however vary greatly according
to the various internal and
external factors it is subjected
to.
1. Normal Skin: Normal is
term widely used to refer to
well balanced skin. The
scientific term for healthy is
endemic. Normal skin is
neither too oily nor too dry.
Identification of Normal
Skin: Normal skin has-
Fine pores
Good blood
circulation
A velvety, soft and
smooth texture.
A fresh, rosy color
uniformtransparency.
No blemishes
And is not prone to sensitivity.
[Rf-6]
Figure-6
2. DRY Skin:-Dry is used to
describe a skin type that
produces less sebum than
normal skin. As a result of
the lack of sebum. Dry skin
lacks the lipoids that it
needs to retain moisture and
build a protective shield
against external influences.
Significantly more women
suffer from dry skin than
men and all skin gets dryer
as it ages.
Identification Of Dry
Skin:
Tightness and a rough
skin feeling often
indicates a dry skin
Elderly women with
dry skin have more
pronounced wrinkles
and lines.(figure-6)
3. Oily Skin: “Oily” describe a
skin type with heighted
sebum production. A over
production is known as
seborrhea.
Identification Of Oily
Skin:
Enlarged, clearly
visible pores.
A glossy shine.
Thicker, pale skin:
blood vessels may not
be visible (figure-6)
4. Combination Skin: In
combination skin types vary
in the T-zone and cheeks the
so called T-zone can differ
substantially from a very
slim zone to an extended
area.
Identification of
combination skin:
An oily T-zone
(forehead, chin and
nose)
Enlarged pores in this
area perhaps with
some impurities.
Normal to dry cheeks.
(figure-6) [Rf-7]
SKIN
EVALUATION
GENERAL PRICIPLES:
Skin evaluation method describe the
severity of erythema, dryness or rash
relative to normal, healthy skin on the
same person. The region of interest
varies depending upon the situation.
For example, if the interest is the skin
condition following dressing removal,
the region of interest would be the
area covered by the dressing. For
diapered infants, skin areas covered
by the diaper are the buttocks, genital
region, perianal region and
interfriginous areas and they are
judged separately and given separate
scores.
For new patients, the
Patients region is likely to have more
compromise involves the area of
involvement / within the region of
interest and severity of the
compromise. The numerical scores
derive from severity of damage, e.g.
inflammation and erythema and area
of (percent) involvement with nearby
areas of normal; uninvolved skin as a
reference. Erythema is scored with a
9-point 0-4 scale with o.5 grade
increments and rash with a 7-point 0-
3 scale with half grade increments.
Dryness is measured on an 11-point
0-5 scale with 0.5 grade increments.
Area of Interest:-for a skin patient,
notice the basic skin coloration as
there is high variability in patient to
patient. This is important because red
and yellow tones vary naturally with
pigmentation and age, especially for
premature infants as the stratum
corneum develops. So judgments are
made relative to normal skin for that
individual patient. Next visualize the
area of interest.
Area of skin involvement: two
examples for judging the amount of
an area that is involved i.e. damaged.
One is for an area on the chest and the
other for the perineal region. This will
vary in size from patient to patient.
The amount of area of skin damage is
relative to the entire area. [Rf-8]
Evaluate your skin in
under 30 min.:-
Even if your skin appears to be
healthy, there is often under-lying
damage invisible to the naked eye and
no one is immune to the effects of
aging. The VISIA R facial imaging
and analysis system provides a quick
and painless evaluation of your skin’s
unique complexion and the advanced
scientific technology objectively
analyzes eight different qualities that
affect your skin’s health and
appearance.
Schedule for free skin evaluation /
complimentary skin
Step 1. The VISIA R system will
take several high quality pictures of
your face using
standard, polarized and ultraviolet
lighting.
Step 2. Analyze:- VISIA R
advanced technology will analyze
your facial images and
display the results on a color monitor.
Step 3 Review:- A skin care
consultant with extensive training and
experience
will remain your results and your
options for improving
your skins unique condition.
IT’S NEVER TOO
LATE…………..OR TOO EARLY.
The results of your VISIA R skin
evaluation allows the qualified staff to
determine the continually improve the
condition of your skin. VISIA R
allows us to objectively evaluate your
skin as your treatment progresses to
ensure thatis health and appearance is
always improving. If you are not
moving forward, you are falling
behind and VISIA R makes certain
that your skin is always advancing
toward optimum health. [Rf-9]
The Study of melanin
Melanin: Melanin is a natural skin
pigment. Hair skin and eye color in
people and animals mostly depends
on the type and amount of melanin.
They have melanin is a bread from for
a group of natural pigments in most
organisms. Melanin is produced by
oxidation of the amino acid and
Tyrosine followed by Polymerization.
The special cells called melanocytes
make melanin.
Everyone has the same number of
those cells make just a little bit of
melanin, your hair skin and the iris of
your eyes can be very light. If your
cells make more than your hair skin
and eyes will be darker. The melanin
is a complex polymer derived from
the amino acid “Tyrosine”. It is
responsible for determining skin and
hair color and is present in the skin to
varying degrees, depending on how
much a population has been exposed
to the Sun historically.
The amount of
melanin in your body makes depends
on your genes. If your parents have a
lot or a little skin pigment, yow will
probably look like them. [Rf-10,11]
Melanin ethnicity figure-7
How Melanin Reacts to
The Sun:-
When you are in the sun, your body
makes more melanin. It may help to
protect the body from harmful UV
Rays. Melanin is a pigment that cells
in your skin create. It helps to protect
your deeper skin layers from the sun’s
“ultra violet rays”. Everyone has
melanin both “Fair and dark” skinned.
The melanin pigment comes in
different shades depending on the
“genetic makeup” of the individuals,
who are exposed to UV light, such as
the sun will produce more melanin for
protection. Aside from determining
skin color, the light absorbent melanin
protects the DNA against UV
radiation from the sun.
But it isn’t enough to keep you safe
from the sun. Your skin is already
damaged if you are sunburned or your
skin has turned slightly darker. That’s
why its important to always cover up
and wear sunscreen. Studies show
people with darker skin get fever
cases of skin cancer than people with
lighter skin. More research is needed
to know if this is because of the
amount of melanin in their skin.
Structure Of Melanin:-
Chemical name – 1(4) 2,5,9(18), 10,
13-hexaene-7,8,15,16-tetrone
Properties:-
Molecular formula – C18H10N2O4
Weight – 318.288 g/mol.
M.P - ‹20C, BP-450 to 550C [Rf-12]
Types Of Melanin:- Some different
types of melanin include “
eumelanin”, “Pheomelanin” and
“Neuromelanin”.
1. Eumelanin:-Eumelanin is found
in the hair, skin and dark areas
around the nipples. It is
particularly abundant among
black populations and provides
balck and brown pigment to the
hair, skin and eyes. “When
eumelanin is present only in
small amounts hair may be
blonde”. [Rf-13,14,15]
2. Pheomelanin:-Pheomelanin is
also found in the hair and skin.
This type of melanin provides
“Pink and Red” Colors and is
the main pigment found among
red haired individuals. “This
type of melanin is not as
protective against UV radiation
induced cancer as eumelanin.
3. Neuromelanin:-Neuromelanin
is a form of melanin found in
different areas of the brain and
loss of this melanin may cause
several neurological disorders.
Other Melanin Types:-
1. Plant Melanin:- plant melanin
is characterized by the principle
of nitrogen economy, as this
element as an important
limiting factor for plant
growing. According to that, the
amino acid 1-tyrosine is not
used for the synthesis of plant
melanin. In general, the
obtained melanin is a polymer
devoid of nitrogen and is
generically named allomelanin.
The color of allomelanin is
always from dark brown to
totally black and structure
depends on the nature of the
main unit oxidited.
2. Fungal Melanin:- As in birds,
reptiles and plants microbial
pigments are mere than just
melanin but the relevance of
this pigment and the great
interest for fungi melanin is
demonstrated by the
publication of a great number
of original papers, book chapter
and many reviews on different
aspects.
A very interesting and
studied case of fungal
melanin is the neuropath
genic fungi Cryptococcus
neoformans. This
basidiomycetous fungus
infects the human brain
and it contains a very
active phenol oxidase
able to oxidize the
catecholamine
neurotransmitters
dopamine and
norepinephrine to
melanin polymers. As
these pigments are
formed in the brain after
infection, a pathogenic
neuromelanin is formed
using the most
compounds.
Aspergillus fumigates,
one of the most
important airborne fungal
pathogens of
immunosuppressed
humans is able to
produce DHN-melanin,
which is predominately
present in conidia.
3. Bacterial Melanin:- Bacterial
melanins are also common and
they have been observed in a
great number of species as their
cultures have black or dark
brown colors. However it is
important to note that not all
dark pigments in bacterial
cultures are indeed melanin
pigments. Bacterial melanins
were first characterized in
Streptomyces, as these species
have been actively pursued in
the search of antibiotics. [Rf-
16]
4. Synthetic Melanin:- finally,
these are also melanins formed
by chemical oxidation from
some diphenolic precursors.
The most common ones are
dopa-melanin and dopamine-
melanin which are easily
formed by chemical oxidation
of those precursors, generally
using atmospheric oxygen or
hydrogen peroxide in basic
media.[Rf-17]
DARK SKIN V/S LIGHT SKIN:-
Are you fair or dark?
Don’t worry. Dark pigment people
living in high sunlight environments
are at an advantage due to the high
amounts of melanin produced in their
skin. The dark pigmentation protects
from DNA damage and absorbs the
right amount of UV radiation needed
by the body as well as protects against
foliate depletion. Dark skin is a
naturally occurring human skin color
is rich in eumelanin pigments. The
evolution of dark skin is believed to
have begun around 1.2 million years
ago.
Due to mass migration and increased
mobility of people between
geographical regions in the recent,
past, dark-skinned populations today
are found all over the world.
On the other hand, light skin is
more prone to sunburn.Light skin
people having less amount of
melanin. This melanin also synthesis
from tyrosine and a leak of tyrosine
can lead to albinosm vitamin
deficiency. Melanin absorbs more UV
Rays but for less amount of melanin
UV light can cause disease in lighter
skin like-cancer, sun burn etc. [Rf-18]
Figure-8
UV RAYS And SKIN:- There are two
types of UV rays in sun light. These
are “UVA” and “UVB”. UVA
spreads skin aging and boosts skin
cancer risk. UVB causes sunburn.
Once the skin is exposed to sunlight,
the melanocytes try to cover all the
cells with melanin like sun hats that
block UV rays.
Luckily we evolved in a world
that’s saturated with UV light, so our
cells have built-in repair kits for the
damaging UV radiation can do. But if
the damage outweighs our capacity to
repair or our repair kits themselves
get damaged, its hello liver spots,
cataracts and way to often skin
cancer.
Sunburn: when
UV meets RNA, the pain, the heat,
the redness, the judgmental looks
from everyone who thought to dress
appropriately. They are all part of the
sunburn experience and judgmental
looks aside. They are all caused by
UVB radiation.[Rf-19,20]
ACTION OF AN CREAM ON
SKIN:-Cream is composed of natural
and chemical substances, it is usually
used to improve the appearance of
blemishes such as birth marks and
melisma/ dark patches. Skin
lightening produces work by reducing
the concentration or production of
melanin in the skin. Do you want your
markup to look better? Do you want
to get rid of the dark spots on your
face? Light color rejuvenates the face
and allows the skin to look more
much younger you. Most people who
use lighteners do so to treat skin
problems such as freckles, age spots,
acne, scars or discoloration related to
hormones. [Rf-21, 22]
HOW TO REDUCE MELANIN:-
Fastestway to permanently reduce
melanin in skin is by undergoing a
laser treatment but this option is very
costly. As an alternative, you can
either buy skin lightening creams
from a store or visit a dermatologist to
get some prescribed products.
Natural home remedies like-
turmeric, aloe Vera, tomato,
cucumber, lemon and potato can also
be used to get rid of excess melanin.
What increases the melanin levels?
These are some of the
common causes that increases the
melanin production in the body-
1. Changes in the hormonal
levels.
2. Excess contact of skin with sun
rays.
3. Some kind of skin disorders
also lead to high melanin in
skin.
4. Lack of adequate vitamins. [Rf-
25]
Despite the fact that an adequate
quant of the melanin pigment is
required to protect skin from the
damaging sunrays. But large quantity
of this pigment makes skin dark. May
be you have heard that exposing skin
under sun makes it dark. This is
because melanin is produced into
skin. [Rf-26]
Apply sun protection lotions. This is
the best precaution you can take
whether your skin is darker or fair.
Using sun protection lotions helps in
proving a layer of shield.
HOME REMEDIES TO REDUCE
MELANIN:-
1. Potato:- The catecholase
enzyme and the blenching
effects of the potato work great
in erasing the darkness and
blemishes from the skin. Make
a paste of potato and daily
apply to your skin area with
high melanin. It will give you a
lighter complexion by reducing
melanin in skin.
2. Lemon Juice:- This natural
product will be mentioned
everywhere when it comes to
lightening of the skin color, the
high vitamin C content and the
acidic characteristic of lemon
work great in lightening the
dark spots and scars. Slice one
lemon and extract the juice.
Mix one tablespoon of honey in
this paste and stir it properly.
Now apply it to your dark skin
and wait for 5 mins. Use it
every day to get a clear and
whitened skin tone.
3. Turmeric:- This is an ancient
Asiatic remedy to improve the
fairness of an individual. It
helps to lower the melanin
levels and make skin fair. To
use this remedy, mix water or
rose water to turmeric powder
and apply this paste to your
face, neck and hands.
4. Cucumber:- Cucumber is little
slow but very effective for
moisturizing the skin and
getting rid of skin
pigmentation. The soothing
properties in cucumber help to
relax the skin and lightening
the skin.
5. Tomato:- tomatoes are
considered to contain the most
powerful form of antioxidants
plus it has vitamin C and the
skin lightening characteristics.
It is great remedy to get rid of
melanin in skin. Mash one
tomato and apply it all over.
After 20 minutes clean it with
water. Use this remedy regular.
It will fade the dark spots. [Rf-
27]
VITAMINS TO REDUCE
MELANIN:-
There are 4 vitamins used to
reduce melanin production-[Rf-28]
1. Vitamin C:- popularly known
as ascorbic acid, it has
antioxidants properties.
Vitamin C seeps deep into the
skin where the melanin
producing cells are located and
inhibits their production.
2. Vitamin A:- Vitamin A is also
known as retinol. Vitamin A
does not penetrate and
eliminate melanin. Regular use
of retinol creams keeps your
skin glowing because it
destroys the accumulated
melanin pigment.
3. Vitamin K:- Vitamin K also
known by the name Sunshine
Vitamin. It is the only vitamin
that our body can produce when
the skin exposed to sunlight.
Dark circles caused due to
excessive melanin production
are also removed when vitamin
K is used.
4. Vitamin E:- Vitamin E is
probably the best vitamin for
all kinds of skin problems.
Though vitamin E has no direct
role in inhibiting melanin
pigment production but it helps
the skin to fight against the
melanin and recover fast.
WHITENING AGENTS
OR MASK:-
Some other whitening agents or mask
are used to reduce melanin or
lightening skin-
1. Chilled organ juice.
2. Tomato juice.
3. Papaya and cucumber face
pack.
4. Lemon and aloe Vera for
instant fair skin.
5. Curd and turmeric fairness
mask.
6. Lemon juice and glycerin,
moisturizer.
7. Exfoliate with strawberry
fairness scrub.
8. Almond and milk skin
whitening and polishing mask.
9. Pineapple face pack and skin
lightening corn flour.
10. Rice powder, banana and milk
instant brightening creamy
mask. [Rf-28,29]
CHEMICALS ARE USED TO
MAKE SKIN FAIRNESS CREAM
AND REDUCE MELANIN:
Best skin whitening chemical agents
which are used to make skin fairness
cream. They shown to inhibit melanin
production. These are-1. Arbutin
2.Vitamin C 3.Glutathione 4.Atelic
acid 5.Kojic acid 6.Rational 7.Fine
Oxide 8.Boric acid 9.Quinoline
10.Citric acid 11.Termeric acid (keto
form) 12.Menobenzene 13.Tretinione
14.Resorcinol 15.Alfa hydroxyl acid
16.Niacinamide17.Mercury
18.Tranexamic 19.Hydroquinone
20.Oxybenzene. [Rf 31, 32, 33, 34,
35, 36]
Common harmful skincare
ingredients:-
1. Parabens
- Phenoxyethanol
- Sodium benzoate
- Benzyl alcohol
2. Formaldehyde
3. Sodium lauryl sulphate /
sodium lauryl sulfate
4. Petrolatum
5. Coal Tar
6. Hydroquinone
- Antioxidants
- Plant-based acids
- Vitamin B3
7. Triclosan
8. Oxybenzone
9. Phthalates
10. Fragrances
11. Alcohol in cosmetics. [Rf-37,
38, 39, 40]
CONCLUSIONS:-Tyrosinase
inhibitors and other agents that affect
the melanin biosynthesis pathway are
widely distributed in materials. These
natural ingredients offer, safer
alternatives to hydroquinone, for use
in topical skin lightening
compositions, additional
functionalities as sun cream,
moisturizers, anti-aging and reducing
the appearance of wrinkles.
SCIENCE BEHIND THE COLOR
OF YOUR SKIN
REFERENCES:-
1. Saladin US. Anatomy and
physiology: the unity of form
and function (3RD
edition) USA
: McGraw Hill 2004.
2. Ross MH, Kaye Gl, Pawlina w.
Histology : A text and atlas
(4TH
edition) USA : Lippincott
Williams and Williams, 2003.
3. Anatomy and Physiology, open
textbooks.
https://opentextbc.ca.chapter5.1
.
4. Revis DR, Seagle Mb skin
anatomy (online) E-medicine,
2006 (cited 7 march 2006).
5. American Osteopathic college
of dermatology : “Actinic
Keratosis /
dermatology.about.com
6. https://int.eucerin.com/online-
available.in URL link
7. American Academy of
dermatology, “ dermatologists”
top 10 tips for relieving dry
skin.
8. https://www.medscayoe.com/o
nline/available.in URL link.
9. Andersonplastic.com/online/av
ailable.in URL link.
10. American Academy of
dermatology, “What gives skin
its color”
11. New Journal of science, "
Melanins : Skin Pigment and
much more.
12. M. em. Wikipedia. com.
13. J.O. Simon and D.N. Peles,"
The red and Black, " Accounts
of Chemical research,
Vol-43, No-11, pp-1452-1460,
2010.
14. G. Prota and R.N. Jhomson, "
Melanin Pigmentation in
mammals, " Endeavour, Vol -
35, no - 124, pp-32-38, 1976.
15. R. Carstam, C. Brinck, A.
Hindemith - Augustsson, H.
Rorsman and E. Rosengreen,
" The Neuromalanin 06 the
human substantia nigra,
Biochemica at biophysica Acta,
Vol -1097, No-2, pp-109-124,
2005
16. J.R. Mencher and A.H. Heim, "
Melanin biosynthesis by strp to
my ces levendulac,"
Microbiology, vol-28, no-4, pp-
665-670, 1962.
17. G. Prota, melanins and
melanogenosis, Academic
press, san diego, calf, USA,
1992.
18. https:/www/avyaskincare.com/
onlin/available in URL link.
19. Slominsk A. wortsman J.
neuroen docrinology of the
skin. endoc. Rev. 2000;
21:457-487.
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