問題一覧
1
A piece of __ is added to a test tube containing __
blue litmus paper 5ml
2
Hastens decalcification by removing calcium ions from formic acid-containing decalcifying solutions, thereby increasing solubility from the tissue
ion exchange resin
3
The most common and the fastest decalcifying agent
nitric acid
4
inferior compared to nitric acid in its role as a decalcifying agent because of its slower action and greater distortion of tissue produced on the decalcified section
hydrochloric acid
5
Other tissue softeners
molliflex 2% HCL 1% HCL in 70% alcohol
6
In chelating agent, The solution should be changed every ___
3 days
7
Not recommended for fluids containing mineral acids such as nitric acid or hydrochloric acid
ion exchange resin
8
55 degrees celsius
complete digestion within 24-48 hours
9
Best all around decalcifier
formic acid in 10% concentration
10
substances which combine with calcium ions and other salts EXAMPLE
iron and magnesium
11
face down on a pad of cotton or gauze saturated with ______ for approximately one hour.
10% hydrochloric acid
12
removal of calcium ions from a bone or calcified tissue through a histological process that makes them flexible and easier to cut
decalcification
13
May be used as simple aqueous solutions with recommended concentrations of 5- 10%
nitric acid
14
In chelating agents: more appropriate for research applications:
immunohistochemistry flourescent in situ hybridization polymerase chain reaction
15
Litmus paper turn to RED-BLUE
Alkalinity
16
substances which combine with calcium ions and other salts
chelating agents
17
Presence of cloudiness
presence of calcium
18
Solutions of chemical test
ammonium hydroxide concentrated ammonium oxalate saturated
19
37 degrees celsius
nuclear staining of Van gieson’s stain for collagen fibers
20
WHAT ARE THE TISSUE PROCESSING
fixation decalcification dehydration clearing infiltration embedding trimming section cutting staining mounting labelling
21
Due to the corrosive action of the acid, it is recommended that the thread be dipped in _____
melted paraffin wax
22
Water rinsing: large specimens
1-4 hrs
23
allows sections to be obtained where the presence of calcium was not anticipated when the specimen was processed
surface decalcification
24
FACTORS INFLUENCING THE RATE OF DECALCIFICATION
concentration fluid access size and consistency agitation temperature
25
Reappearance of a white precipitate within ___
30mins
26
The degree of decalcification may then be measured by
physical and x-ray method
27
Water rinsing: small specimen
30mins
28
interfering with the normal cutting of sections and staining of specimens
incomplete decalcification
29
Decalcification time: small bones or specimens
1-3 weeks
30
spoils the staining of basophilic elements such as cell nuclei and in certain circumstances can cause maceration of the softer tissue elements
prolonged decalcification
31
If solution remains clear after __, decalcification is __
30mins complete
32
When decalcification is complete, the acid must be removed by three changes of ____
70-90% ethanol
33
Tissue volume for decalcification
20:1
34
done after fixation and before impregnation, to ensure and facilitate the normal cutting of sections
decalcification
35
___ has been shown to speed up the process of decalcification significantly-from days to hours
microwave irradation
36
optimal pH in edta
7-7.6
37
Optimal temperature
18-30
38
What is the example of chemating agents?
neutral edta
39
May act both decalcifyinga agent and tissue softener
perenyi’s fluid
40
produces good nuclear staining and if used in 1% solution with 70% alcohol
hydrochloric acid
41
Simple, reliable and convenient method recommended for routine purposes, to detect the presence of calcium in the decalcifying solution.
chemical test
42
Most expensive but is the most ideal, most sensitive and most reliable method of determining the extent of decalcification due to its ability to detect even the smallest focus of calcium which appears opaque
x-ray
43
*Reappearance of a white precipitate within __ is what?
presence of calcium ions
44
most common chelating agent
edta and salt (VERSENE)
45
moderate-acting decalcifying agent which produces better nuclear staining with less tissue distortion, and is safer to handle than nitric acid or hydrochloric acid
formic acid
46
Decalcification time: NITRIC ACID
12-24hrs
47
In this method, hard tissues are placed in the decalcifying agent in a ____ for intermittent periods with regular changes of the solution till the end point is reached
microwave oven
48
It is highly corrosive to skin and mucous membranes and carcinogenic
chromic acid
49
recommended for routine decalcification of postmortem research tissues
formic acid
50
Decalcification time: cortical bone
6-8 weeks
51
preferred if preservation of nuclear DNA is important
chelating agents
52
A very weak decalcifying solution suitable only for minute pieces of bone
sulfurous acid
53
If the litmus paper turn RED due to
acidity of the fluid
54
Decalcifying fluid usually change every ___
24-48 hours
55
most widely used agents for routine decalcification of large amounts of bony tissues because they are stable, readily available, and relatively inexpensive as compared to other decalcifying agents
acid decalcifying agents
56
require manipulation, bending, probing or trimming of the specimen to "feel" for remaining calcified areas
physical test
57
A process whereby positively charged calcium ions are attracted to a negative electrode and subsequently removed from the decalcifying solution
electrophoresis