51.   It was not known what caused the failure.

52.   It is not known what caused the failure, considered a devastating blow to the troubled Russian space program.

53.   Loomis, fined for the second time in two races, said an oversight during preparation of the car caused a failure of its suspension system.

54.   Researchers have long suspected that some heart-transplant failures are caused by viruses.

55.   Russian news reports suggested poor fuel may have caused engine failure during take off.

56.   Severe cases cause liver failure and can require a transplant.

57.   Several days later, dozens of children came down with a deadly complication called HUS that causes kidney failure.

58.   She said the failure was both caused by the inefficient intermediary role of the banking system as well as a lack of productivity in the real sector.

59.   The caffeine spray causes cardiac failure.

60.   The commission determined the structural failure was caused by excessive stresses on the lowest of the four tiers.