<|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: due to ethical restrictions, study data cannot be made publicly available. requests for the data can be sent to the ethics committee of fudan university, shanghai cancer center (dr. zhang wei-jin, andwater@163.com).<|eot_id|><|start_header_id|>assistant<|end_header_id|>

yes<|eot_id|>