Continued Diminished Prevalence of the Lucke Renal Adenocarcinoma in Minnesota Leopard Frogs
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چکیده
No Luck? renal adenocarcinomas were detected at autopsy of 1216 northern leopard frogs (Rana pipiens) collected in Minnesota during the spring and autumn of 1978 and the spring of 1979, seasons in which the tumor was formerly obtained with a high frequency. The prevalence of renal tumors has been declining in Minnesota since at least 1966, and R. pipiens has become progressively scarce in Minnesota since that time. We suggest a causal relationship between reduced frog populations and decreased tumor prevalence.
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