Healing is a two-way road. Either you believe the Doctor can heal you with what he has, or you believe that God can heal you with what he has. So, why precisely do people believe in our Doctors more than the creator of our bodies? He created us in the first place, and he knows exactly how things work, without the side affects.
Some people believe that God doesn't do healing anymore with anybody, others believe that God only does few miracles, and few believe that God still does miracles today as he did when he was present on this Earth.
Anyone who's paying any attention while reading the gospel accounts of Jesus, has a hard time missing that Jesus healed people of physical illnesses. Not only did Jesus do it early and often (so often that during his life, His healings were seen as a trademark of his work,) but he is reported in Scripture to have giving his followers the ability to do the same, and more. As to the church actually following through on that promise, see Acts 3:1-16
I've heard people say "It's Gods will" or "I'll just leave it up to God" when faced with serious illness or tragedy. Don't fall into that trap. God wants us to pray to him for help, and also believe in him, that he hears us.
Many of us don't want to get all worked up about something and have it not turn our right, (as in praying to God for healing and not getting it) and perhaps that's what we've been brought up to do. To think like. The saying, "don't get your hopes up" is one example of disbelief that gos on everyday and no one knows or understands what they are prophesying, and by that I mean, you will get according to your faith level. For example, if you have great faith in God about something, he's going to show up. If you don't have much, or any faith, the result will return to you with how much faith you put into what you desire. (Make sense?)
(Thurman Scrivener has some great stories to tell of miraculous healings. He is a Pastor who is in the healing ministry.)
For now I want you to think about this. Thurman is getting all the results, and if God doesn't heal anymore, or if he only does it every once in a while, why then would this man who believes God does it every time, is getting the results every time he believes it will happen? How can he be right and wrong when it comes to this?
Some verses I would like to leave you with are these:

Matthew 10:1 (NKJV) And when He had called his twelve disciples to Him, He gave them power over unclean spirits, to cast them out, to heal all kinds of sicknesses and all kinds of disease.

Luke 10:19 (KJV) Behold, I give unto you power to tread on serpents and scorpions, and over all the power of the enemy and nothing shall by any means hurt you.

Luke 8:47-48 (NKJV) Now when the woman saw that she was not hidden, she came trembling; and falling before Him, she declared to Him in the presents of all the people how she had touched Him and how she was healed immediately. (48) And He said to her, "Daughter, be of good cheer; your faith has made you well. Go in peace."