2. 




3. 

 Night blindness

Bitot'spot
 Keratomalacia

4. . . (I.U. =
international unit) . .
-

5. 
P=0.003
94.8 (<20
µg/dl), 5.2
P<0.05

7.  http://www.siamhealth.net/public_html/Health
/good_health_living/vitamin_and_mineral/vita_a
_def.htm
 http://guru.sanook.com/search/%E0%B9%82%E
0%B8%A3%E0%B8%84%E0%B8%95%E0%B8%B2
%E0%B8%9A%E0%B8%AD%E0%B8%94%E0%B8
%88%E0%B8%B2%E0%B8%81%E0%B8%81%E0%B
8%B2%E0%B8%A3%E0%B8%82%E0%B8%B2%E0
%B8%94%E0%B8%A7%E0%B8%B4%E0%B8%95%
E0%B8%B2%E0%B8%A1%E0%B8%B4%E0%B8%99
%E0%B9%80%E0%B8%AD