Excimer laser radiation at 193 nm and 248 nm was used to create linear etch perforations of enucleated calf corneas. The etch depth per pulse was determined for various exposures, and specimens were examined by light and transmission electron microscopy. Compared to 248 nm, excimer laser ablation at
A quantitative ultrastructural study of the pinealocyte of the chipmunk (Tamias striatus) during the daytime and at night
β Scribed by Dr. Michal Karasek; Thomas S. King; John T. Hansen; Russel J. Reiter
- Publisher
- John Wiley and Sons
- Year
- 1982
- Tongue
- English
- Weight
- 371 KB
- Volume
- 7
- Category
- Article
- ISSN
- 0360-4012
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
Dayβnight differences in the areas of granular endoplasmic reticulum, Golgi apparatus, denseβcore vesicles, and lysosomelike bodies were analyzed morphometrically in the pinealocytes of the chipmunk. The area of lysosomelike bodies was greater at night and lower during the daytime. In contrast, the areas of granular endoplasmic reticulum and denseβcore vesicles were greater during daytime and lower at night. Our observations suggest the existence of 24βhour rhythms in the areas of these structures, perhaps indicative of a pineal rhythm in secretion, whether indolic or peptidergic.
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