منابع مشابه
Maternal Night Blindness: A New Indicator of Vitamin A Deficiency
N ight blindness—the inability to see after dusk or at night—is the most common ocular manifestation of moderate to severe vitamin A deficiency. Poor dark adaptation leading to night blindness occurs when there is decreased production of a vitamin A–dependent photosensitive pigment, rhodopsin, in the retinal receptors responsible for seeing under low levels of illumination (rods). Normally, whe...
متن کاملNight blindness and conjunctival xerosis caused by vitamin A deficiency in patients with cystic fibrosis.
Forty three patients with cystic fibrosis, aged 8-44 years (median 16 years), were examined for evidence of vitamin A deficiency. Eight patients had abnormal dark adaptation tests and three had conjunctival xerosis. Serum vitamin A and retinol binding protein concentrations were significantly lower in the affected patients who were also more likely to have abnormal liver function tests. Five pa...
متن کاملHistorical and practical uses of assessing night blindness as an indicator for vitamin A deficiency
n The assessment of vitamin A status is critical for the planning, implementation, monitoring and evaluation of vitamin A deficiency prevention and treatment programmes. Determination of night blindness is one of the traditional methods of assessing vitamin A deficiency. A variety of subjective and objective methods have been used, however, reported night blindness, the most common method to as...
متن کاملP 417 Night blindness due to chronic pancreatitis: Vitamin A deficiency despite oral pancreatic enzyme therapy
B Confirming the diagnosis of night blindness in our patient, the scotopic response in his electroretinogram (ERG) was distinctly reduced while the photopic response was normal. When his blood was examined for a low level of vitamin A as a possible cause for night blindness, we found the value to be reduced below normal (17 pg/dl versus 25-70 pg/dl in normal subjects). Treatment with vitamin A ...
متن کاملNight blindness due to vitamin A deficiency associated with resected adenocarcinoma of the pancreas.
Dear Sir, W e write to present a rare case of night blindness caused by vitamin A deficiency secondary to resected adenocarcinoma of the pancreas. To our knowledge this is the first reported case of this association. A 62 year-old man presented to the eye clinic with a 12mo history of worsening nyctalopia and colour perception. Three and a half years previously, he underwent a Whipple's procedu...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1958
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.44.7.648