Medicina

HISTOLOGICAL TECHNIQUES

1. Direct observation of living tissues and cells
Cells are studied while still alive  Colorless  Phase contrast microscope  Amoeboid movement, phagocytic activity ofblood cells


1. Direct observation of living tissues and cells
a.

Exteriorization and transillumination of organs - brought outside the body cavity - moist chamber for transillumination anddirect microscopic examination ex. Release of secretory material from pancreatic cell and ovulation

1. Direct observation of living tissues and cells
b.

Transparent chamber method-installation of chambers of metal and glass in the flexible ear of rabbits

2. Cell, Tissue and Organ Culture
Cells, tissue and organ studied in vitro “in glass” cultivation Cell Culture - dividing cellsare transferred from vessel to vessel as their numbers continously increase ex. Short term culture of wbc to study human chromosome




Tissue Culture - ( immature tissue culture) - embedded incoagulum of blood plasma containg embryo juice - incubated - cells proliferate in the zone of outgrowth



Organ Culture - maintenance of mature tissue or organ fragments Use: study directeffects of drugs or hormones on various tissue

3. Mechanical Micromanipulation and Microdissection
Instrument: Microminipulator Use: - moves glass needles or pipettes so a single cell can bemanipulated or dissected - moves fixed cells while studied under SEM

4. Use of Radiation Probes


Selective staining of organelle with colored dye combined with high intensities of light available fromlaser sources, provides the opportunity for a new form of cellular microsurgery.

5. Cinematography
Pictures are taken thru the objectives of microscope Use: 1. record cell activity ex. Movementof cell and organelles mitosis
•

6. Differential Centrifugation


One of the most valuable & widely used methods in biological chemistry.
Cells (disrupted) homogenate Layered in sucrose...