<|begin_of_text|><|start_header_id|>system<|end_header_id|>

You are an expert at identifying data availability statements in scientific text. A data availability statement describes where research data can be found or how it can be accessed.<|eot_id|><|start_header_id|>user<|end_header_id|>

Determine if the following text contains a data availability statement. Answer with 'yes' or 'no'.

Text: our data are indeed obtained from the third party (tianjin institute of urology), but they are only available upon request because of ethical restrictions imposed by the second hospital of tianjin medical university. readers may contact dongwen wang (dongwen_shanyi@126.com) to request the data.<|eot_id|><|start_header_id|>assistant<|end_header_id|>

yes<|eot_id|>