Centesis

In medicine, sampling is gathering of matter from the body to aid in the process of a medical diagnosis and/or evaluation of an indication for treatment, further medical tests or other procedures. In this sense, the sample is the gathered matter, and the sampling tool or sampler is the person or material to collect the sample.

Sampling is a prerequisite for many medical tests, but generally not for medical history, physical examination and radiologic tests.

In terms of sampling technique, a biopsy generally refers to a preparation where the normal tissue structure is preserved, availing for examination of both individual cells and their organization for the study of histology, while a sample for cytopathology is prepared primarily for the examination of individual cells, not necessarily preserving the tissue structure. Examples of biopsy procedures are bone marrow biopsy, brain biopsy, skin biopsy and liver biopsy.

Different types of matter that are sampled can be categorized by solidness versus fluidity, such as:

Body fluid sampling include:

The sampled matter can be analyzed for various components, for example:

Microbiological sampling include:

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