`……………..` is used for the treatment of leukaemia.

Answer

To solve the question regarding which substance is used for the treatment of leukemia, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Condition**:
- Leukemia is a type of cancer that affects the blood and bone marrow. It is characterized by the overproduction of abnormal white blood cells.

2. **Identify Treatment Options**:
- Various treatments are available for leukemia, including chemotherapy, radiation therapy, and targeted therapies. Among these, certain radioactive isotopes are used.

3. **Research Radioactive Isotopes**:
- Radioactive isotopes can be used in medical treatments due to their ability to target and kill cancerous cells.

4. **Focus on Phosphorus-32**:
- Phosphorus-32 (P-32) is a radioactive isotope of phosphorus. It emits beta radiation, which can be effective in treating certain types of leukemia.

5. **Confirm Its Use**:
- P-32 is specifically used in the treatment of blood disorders, including leukemia and polycythemia vera. It helps in reducing the number of abnormal blood cells.

6. **Conclude the Answer**:
- Therefore, the answer to the question is that **Phosphorus-32** is used for the treatment of leukemia.

### Final Answer:
**Phosphorus-32** is used for the treatment of leukemia.

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