Stingray injuries can be accompanied by symptoms (some mild, some serious) such as those listed below:  There is a puncture wound. The hole from the stinger (barb) can be quite large and may have a jagged appearance. The stingray rarely leaves the barb behind, but on rare occasions it may break off in the wound. The victim experiences immediate and severe pain radiating from the puncture site. The wounded area swells significantly. The puncture site bleeds. Skin color around the wound initially appears blue, then changes to red. The victim sweats abnormally. The victim becomes faint, weak, or dizzy. The victim develops a headache. The victim experiences nausea, vomiting, or diarrhea. The victim experiences shortness of breath. The victim has a seizure or experiences muscle cramping or paralysis. The following are strong indications that medical assistance is immediately required:  The injury is located in the victim's abdomen, chest, neck, or face. The victim bleeds profusely. The victim experiences difficulty breathing, itching, nausea, tightness in the throat, rapid pulse, dizziness, or loss of consciousness. Lay the victim down on the ground if the incident occurs near shore, or on the floor or seat of a boat if the incident occurs in open water with a vessel nearby.  Getting out of the water quickly and safely is essential to prevent further injury. If the victim is vomiting, turn him on his side to prevent choking. This is best done by applying pressure to the puncture site with a clean cloth or towel.   If no clean cloth or towel is available, a shirt or other piece of clothing can be used. Only apply as much pressure as is needed to stop or significantly slow the loss of blood. If the victim is conscious, ask her whether the pressure is tolerable or if it is causing significantly more pain. If the stingray barb is still present in the wound, removing it will stop additional toxins from being released into the wound. However,  the barb is serrated and will slice the skin as it is extracted, which...

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Write a summary of the previous text in Vietnamese:
Quan sát các triệu chứng thường gặp. Tìm sự chăm sóc y tế ngay lập tức nếu các triệu chứng có vẻ nghiêm trọng. Đưa nạn nhân ra khỏi nước và vào nơi an toàn. Cầm máu. Dùng nhíp để lấy gai ra nếu không có sự chăm sóc y tế.