Short day lengths induce gonadal regression within 6 weeks in Siberian hamsters, but this inhibitory effect eventually wanes and reproductive competence is regained after 4-6 months in short days. These experiments were undertaken to determine whether continuous exposure to short days for several months is necessary to induce neuroendocrine refractoriness, or if a few weeks of short days are su...

Equine abortion virus (EAV)-induced hepatitis in hamsters presents an interesting animal model for the evaluation of drugs possessing anti-deoxyribonucleic acid virus activity. These experiments demonstrate that 9-beta-d-arabinofuranosylhypoxanthine 5'-monophosphate (ara-HxMP), a new synthetic, water-soluble, antiviral agent, effectively controls this disease in hamsters with a therapeutic inde...

Golden Syrian hamsters were placed individually in cages with three drinking bottles--one empty, one containing water, and the third containing water and ethanol. Control hamsters received water only. After 1 year the experimental hamsters showed a significantly lower concentration of leucine-enkephalin-like immunoreactive substance in the basal ganglia than the control hamsters. This finding i...

Introduction: Skin cancer has been increased day by day, but it can be cured if it diagnosed early. After reviewing the scientific literature about 980 nm diode laser, and its multiple advantages on skin diseases. We studied in this paper the effectiveness of this type of laser on the progression of skin cancer among hamsters which were exposed to carcinogen on the bac...

Objective(s): Adipose tissue-derived mesenchymal stem cells (AT-MSCs) with more potent immunomodulatory effects, greater proliferative potential and secretion of growth factors and cytokines in comparison with bone marrow derived MSCs are more appropriate for cell therapy. The aims of the present study were to evaluate the histomorphometric effect of AT-MSCs allotransplantation on regeneration ...

Fetal tissue from primiparous hamsters prevented simian virus 40 (SV40) tumorigenesis in male hamsters, whereas fetal tissue from multiparous hamsters did not. The parity status of normal (uninoculated) hamsters also influenced the cytotoxicity of their lymphoid cells against tumor cells. Lymph node cells from nonpregnant primiparous and multiparous animals were cytotoxic in microcytotoxicity t...

Hamsters are an ideal animal model for a variety of biomedical research areas such as cancer, virology, circadian rhythms, and behavioural neuroscience. The use of hamsters has declined, however, most likely due to the dearth of genetic tools available for these animals. Our laboratory uses hamsters to study acute social stress, and we are beginning to investigate the genetic mechanisms subserv...

induced solid tumors in mice, rats, and hamsters. These virus isolates are now known as MSV-H3 and MSV-M. The histol ogy of these tumors has been described extensively by a number of workers (4, 27, 35). Soehner and Dmochowski (32) have recently reported the induction of osteosarcomas in rats and hamsters by both MSV-M and MSV-H. They have also reported the cell-free transmission of these tumor...

Oligodendrocytes and myelin in the corpus callosum of black tremor and normal hamsters aged over 1.5 years were ultrastructurally examined to determine the myelination index (ratio of myelin thickness/diameter of axon), percentage of naked axons, and proportions of oligodendroglial subtypes (light, medium and dark). The mutant hamsters were remarkably hypomyelinated, with a low myelination inde...

Twelve adult female hamsters were given free access to horizontal disc exercisers over a 41-day period while 10 hamsters of matching weight remained sedentary. An accelerated weight gain of 1.1 g/day on Days 7-41 of activity and during 21 days following its termination led to a 33.8-g upward displacement of exercising hamsters' weight above the weight level maintained by sedentary controls (P <...