Which hospital is Jiangsu designated for immigration to the United States and physical examination?

Not in Jiangsu. Only to Shanghai. In official website, the US Immigration Service mentioned that there are only 1 designated hospitals respectively.

Beijing, Shanghai, Chengdu, Guangzhou and Fuzhou. Because your visa is an immigrant, it is recommended to go to Guangzhou for a physical examination one week before the face-to-face visa. The address is on the 5th floor of the East Tower of Poly Building opposite the Immigration Bureau. Very convenient. The result came out in three days. Let him take it to the interview. Other places are not recognized as valid after entry and exit inspection.