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What is a culture and sensitivity test?

A collection of a urine sample, blood sample or other body fluid samples are cultured in medium and analysed with for sensitivity. A “C&S” is a diagnostic lab procedure used to identify the type of bacteria and to determine which antibiotics can successfully fight an infection. C&S is primarily used to find bacteria. The absence of bacteria does not mean …

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What is a Csa climate?

Unless you are a meteorologist (a person who studies the weather), it is unlikely that you will know that this is, in fact, a coded description of the climate of the Mediterranean regions. Devised by a Russian meteorologist, Vladimir Koppen, in the early 20th century, the code (see below) is based mainly on temperature and rainfall and is now used …

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What is a cryosurgery?

It is the technique of using extreme rapid cooling to freeze tissues, thereby destroy them. Rapid cooling to temperature below freezing point produces irreversible cell damage and cell death occurs at -20 to -90 degree Celsius. Freezing produces white areas of necrosis. It is applied in the treatment of malignancies, vascular tumours and aggressive tumours.

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What is a cogwheel train?

A cogwheel train is a train fitted with one or more cogwheels, which mesh with the toothed rail-rack, running usually between the normal rails. The system, operating on rack and pinion arrangement, is used in regions where trains operate on steep heights within a short span of time. Most cogwheel railways are mountain railways, although a few are transit railways …

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What is a chromophore?

A chromophore is a group of atoms and electrons (or moiety) i.e. part of organic molecules responsible for its colour. It is an extended delocalised systems of electrons in a compound which gives its colour e.g. chlorophyll’s porphin ring, or an azo dyes benzene ring linked to N=N double bond. When a molecule absorbs certain wavelengths of visible light and …

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What is a chemical bond? How is it formed?

A chemical bond is one in which atoms of different or same elements combine to become stable. There are two types of chemical bonds – electro-valent bond and co-valent bond. In an electro-valent bond, a metal donates an electron to a non-metal and forms the bond. Such bonds are very strong. A co-valent bond is formed between non-metals only. These …

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What is a catalyst?

A catalyst is any substance which causes a chemical reaction without itself undergoing any chemical change. Many industrial processes depend on this property. A simple example is when oxygen and hydrogen combine together quickly in the presence of platinum. Platinum is therefore, the catalyst. It is believed that this is due to the gases being absorbed on the surface of …

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