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Bacterial infections may be treated with antibiotics, which are classified as bacteriocidal if they kill bacteria, or bacteriostatic if they just prevent bacterial growth. There are many types of antibiotics and each class inhibits a process that is different in the pathogen from that found in the host. An example of how antibiotics produce selective toxicity are chloramphenicol and puromycin, which inhibit the bacterial ribosome, but not the structurally different eukaryotic ribosome. Antibiotics are used both in treating human disease and in intensive farming to promote animal growth, where they may be contributing to the rapid development of antibiotic resistance in bacterial populations. Infections can be prevented by antiseptic measures such as sterilizing the skin prior to piercing it with the needle of a syringe, and by proper care of indwelling catheters. Surgical and dental instruments are also sterilized to prevent contamination by bacteria. Disinfectants such as bleach are used to kill bacteria or other pathogens on surfaces to prevent contamination and further reduce the risk of infection.

What is common prevention method of infections in medicine?
Answer: sterilizing
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The Chinese counterattacked in April 1951, with the Fifth Phase Offensive, also known as the Chinese Spring Offensive, with three field armies (approximately 700,000 men). The offensive's first thrust fell upon I Corps, which fiercely resisted in the Battle of the Imjin River (22–25 April 1951) and the Battle of Kapyong (22–25 April 1951), blunting the impetus of the offensive, which was halted at the "No-name Line" north of Seoul. On 15 May 1951, the Chinese commenced the second impulse of the Spring Offensive and attacked the ROK Army and the U.S. X Corps in the east at the Soyang River. After initial success, they were halted by 20 May. At month's end, the U.S. Eighth Army counterattacked and regained "Line Kansas", just north of the 38th parallel. The UN's "Line Kansas" halt and subsequent offensive action stand-down began the stalemate that lasted until the armistice of 1953.

What was the Fifth Phase of the Chinese counter initiative called?
Answer: Chinese Spring Offensive
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Kievan Rus' also played an important genealogical role in European politics. Yaroslav the Wise, whose stepmother belonged to the Macedonian dynasty, the greatest one to rule Byzantium, married the only legitimate daughter of the king who Christianized Sweden. His daughters became queens of Hungary, France and Norway, his sons married the daughters of a Polish king and a Byzantine emperor (not to mention a niece of the Pope), while his granddaughters were a German Empress and (according to one theory) the queen of Scotland. A grandson married the only daughter of the last Anglo-Saxon king of England. Thus the Rurikids were a well-connected royal family of the time.

Who did Yaroslav's sons marry?
Answer:
daughters of a Polish king and a Byzantine emperor