Saturday, November 1, 2008
CD-ROM 1982
Edison's phonograph is the first sound recording machine.
1935
German firm age make the first tape recorder to play magnetized plastic tape.
1960
Invention of the laser, used to scan compact disks.
1982
First music compact disks go on sale.
1990
Publishers issue books as CD-Roms.
1998
First PCs with DVD disk drives. DVD's hold 30 times as much information as CD-Roms.
Sunday, October 12, 2008
Conjunctivitis
Do you know about conjunctivitis and symptoms.
Conjunctivitis is an illness that affects the inside of the eyelid. It can also affect the thin covering of the eye. It is infectious. This means it is passed from one person to another.
You use your eyes to see. Light enters each eye through the pupil in the centre of the eye. The eye is covered by a thin skin called a membrane. The membrane stops dirt and germ getting into the eye. So do our eyelids and eyelashes.
Conjunctivitis is usually caused by bacteria or viruses. These germs are so tiny you can only see them through a microscope. You catch conjunctivitis when the bacteria or virus touches your eyes. If a friend has conjunctivitis they might rub some of the germs on to their towel. If you then use the same towel, you may rub the germs into your own eye. Some germs in the swimming pool water may also get into your eyes.
Strong chemicals can also cause conjunctivitis. The chemicals burn the delicate covering of the eye. People who use strong chemicals should wear goggles to protect their eyes.
Symptoms
The first symptom of conjunctivitis is often an itchy or burning feeling in the eye. Tears help wash dirt and germs out of the eye. When you have conjunctivitis your eye may become a lot more watery than usual. It can also become very red. As your body fights the conjunctivitis germs, it makes a sticky, yellow pus. When you are asleep the pus may make your eyelids stick together.
How to handle this problem?
Use cotton wool dabbed in clean, salty water to wipe away the pus. Very bad conjunctivitis is called pink eye because the whit part of your eye becomes red. If you have conjunctivitis you should have it checked by a doctor. If the illness is caused by a virus, you will have to wait for it to get better on its own.
If it is caused by bacteria, like this, the doctor will prescribe an antibiotic ointment. Antibiotics can kill bacteria, but not viruses. The doctor will tell you how often to apply ointment. An adult will have to squeeze some ointment into your eye for you. The ointment will start to work after a few days. You must go on using if for as long as the doctor tells you, or your eye may get sore again.
Friday, October 10, 2008
Antibiotics
An antibiotic is a normal metabolic product of actinomycetes and other microorganisms and it kills or inhibits the growth of other microbial species. For example, streptomycin’s block protein synthesis in their targets. Penicillins disrupt formation of covalent bonds that hold bacterial cell walls together. Penicillin derivatives cause the wall to weaken until it ruptures. The known antibiotics don’t’s have comparable effects on protein coats of viruses. If you have a viral infection, antibiotics won’t help.
Antibiotics must be carefully prescribed. Besides performing their intended function of counterattacking pathogens, some can disrupt the normal populations of bacteria in the intestines and of yeast cells in the vaginal canal. Such disruptions can lead to secondary infections.
Overprescribed antibiotics have lost their punch. Over time, they destroyed the most susceptible cells of target populations and favored their replacement by more resistant ones. Antibiotic-resistant strains have made tuberculosis, typhoid, gonorrhea, staph infections, and other bacterial diseases more difficult to treat. In a few cases, superbugs that cause tuberculosis cannot be treated successfully.
Wednesday, October 1, 2008
How to Prevent Headache?
Tension type headache, Cluster headache, Migraine, Facial headache and chronic daily headaches and ice cream headache.
Tension type headache called muscle construction headache, this headache type is mild to moderate only. Sensory sensitivity to noise or light is more likely to be associated with migraine. The patient’s often describe the pain as a feeling of tightness or squeezing.
Cluster headache
This type headache is very rare, it is affect 1 in 1000 men and 1 in 6000 women. Commonly it will come night time, symptoms are eyes are red and waters, nose is blocked.
Migraine
This is severe headache type, it will affect depending upon daily life suffers and stresses. Commonly 17% women and 6% men affected. This migraine symptoms are nausea and vomiting, photophobia light and noise, aggravated by routine activities.
Facial headache
Acute sinusitis, Trigeminal neuralgia, post herpetic neuralgia, and Temporomandibular joint.
Chronic daily headache
It will come monthly twice, in can affect in the children and in the very old.
Ice cream headache
Commonly the patient is young age and the patient’s describe a short piercing pain. Sometimes, the patient has multiple attacks per day on a daily basis.
Tuesday, September 16, 2008
Hearing
Many arthropods and nearly all vertebrates have acoustical organs and so can hear sounds. For example, humans and other land-dwelling mammals have a pair of distinctive ears. Small organs, flush with the body surface, serve comparable functions in insects and amphibians. Such organs are located on the front legs of crickets and near the hind legs of grasshoppers.
Hearing starts with acoustical receptors, which are vibration-sensitive mechanoreceptors. A vibration is a wavelike form of mechanical energy. For example, clapping produces waves of compressed air. Each time hands clap together, molecules are forced outward, so a low-pressure state is created in the region they vacated. The pressure variations can be depicted as a wave form, and the amplitude of its peaks corresponds to loudness. They frequency of a sound is the number of wave cycles per second. Each cycle extends fro the start of one wave peak to the start of the next. The more cycles per second, the higher the frequency, and the higher the perceived pitch of the sound.
When sound waves arrive at an acoustical organ, they encounter a membrane and make it vibrate. In invertebrates, vibrations directly stimulate mechanoreceptors attached to the membrane. In vertebrates, the membrane vibrations cause a fluid inside the ear to be displaced. The fluid movement causes mechanoreceptors to bend. With enough deformation, action potentials are produced. They travel along an auditory nerve leading from the receptors to the brain.
The introduction to this chapter described the sense of hearing that is associated with echolocation. Although we cannot hear them, the extremely high frequency waves (ultrasound waves) produced by an echolocating bat are not weak. They have been measured at 100 decibels which is in the same range as thunder or a freight train racing past.
Sunday, September 14, 2008
Cloaning
In 1996 scientists in Scotland cloned a sheep, which they named Dolly. They did this by taking a body cell from an adult sheep and using its DNA to make an exact copy f that sheep. In the future cloning could allow scientists to produce tailor-made body organs for transplant patients, or create whole herds of cows or sheep that produce useful drugs in their milk. The technique could also be used to enable infertile couples to have a child who would be a clone of one of them.
1953 – Francis Crick and James Watson discover the structure of DNA
1973 – Stanley Cohen and Herbert Boyer carry out first Genetic Engineering with bacteria
1986 – Human Genome project set up to list sequence of entire human genome
1990 – First trials for ‘Gene Therapy’
1996 – Dolly, a cloned sheep, created by Roslin Institute Scotland
2000 – First draft of human genome published.
Wednesday, September 10, 2008
D4 syndrome
D4 syndrome is commonly known as middle back pain. The patients affected by this syndrome have pain between neck and the lumbar region (Lower back). Initially the pain occurs in the central position of the back, then gradually spreads to the lateral portion (side) of the chest. In some cases the pain may even be felt in the centre of chest causing breathing difficulty.
Reason: While driving we tend to berid a little forward coupled with this when the vehicle jolts in a pit it forces out body to bend downwards causing the posterior back ligament to stretch and lose its elasticity. The inter vertebral disc can also slip posteriorly (back wards) and it compresses the spinal cord causing pain. Whenever normal positioning of the bone is disturbed out body tends to deposit osteophytes (bone forming cells). This deposition of osteophytes compresses the nerves which branch from the spinal cord causing radiating pains in the chest. If this osteophytes compress the respiratory nerves, the patient will get some breathing problem. Problem similar to above can also be caused by wrong posture.
Bending forward creates angulation in the 4th thoracic vertebra (middle back) resulting pain in scapula region. Thus it is called D4 syndrome.
Treatment: In combined therapy, homoeopathic medicines, machines like shortwave diathermy ultrasound and special manipulation techniques are used. In physiotherapy ultrasound and shortwave diathermy are the effective treatment to remove the osteophytes. The vibration from the ultrasound and the electromagetic waves from the shortwave diathermy remove the osteophytes.
In addition, by effective manipulation we can rearrange the vertebrae to normal alignment. To maintain the normal positioning of the vertebrae the patient should do muscle strengthening exercises regularly. In these cases, traction treatment is not effective. Homeopathic medicines like Kali carb, pulsatilla, Cal Carb. Rhus tox can reduce the pain and inflammation immediately. They prevent the recurrence also.