The Nikon MicroscopyU confocal microscopy image gallery was created with a PCM-2000 confocal scanning system interfaced to a Nikon Eclipse E600 upright microscope. Images were recorded in successive z-axis serial sections with C-Imaging Systems software with excitation illumination provided by an argon-ion and/or a helium-neon laser.

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Because of legal, financial, and ethical restrictions, biological researchers in the cosmetics and pharmacological industries are always searching for realistic and convenient models of human cells and they often turn to hamster cells. Chinese hamster ovary (CHO) cells (sometimes Syrian hamster cells) are very popular for histological, viral, and genetic research, because they are easily cultured as animals or tissues in the laboratory and because hamsters are small, cheap, and reproduce prolifically at an early age.

Introduced in the 1960's, CHO cells have twin female X chromosomes and a nutritional need for the amino acid proline. With this knowledge, researchers are able to manipulate the cells in genetic and developmental experiments. Cancer studies using CHO involve inducing mutations, describing cellular processes, and examining the curative effects of potential treatments. Most recently, hamster cells were used in the human genome project since they have the ability to hold on to pieces of human DNA. This aids the mapping of the human genome by allowing the creation of scorecards for each DNA fragment (or genetic marker) inserted.

Some researchers argue that hamster cells are not very good models of humans since hamsters are able to manufacture their own vitamin C from glucose while humans cannot, and because hamster cells are programmed for death decades before human cells. They stress that stretching the results of experiments from hamster cells to humans may lead to false conclusions and using commercially available cell lines blindly could lead to artifacts if unknown mutations have occurred. Histologists counter that they have modified natural hamster cells into a standardized cellular line that is programmed to proliferate almost indefinitely via transformation and it is an ethical solution to animal and human experimentation.