X-ray film was originally recorded on glass plates but nitrocellulose film replaced them during WWI due to its greater feasibility. Double emulsion film was later found to respond faster to x-rays. By 1924, cellulose acetate replaced the flammable nitrocellulose film. Radiographic film consists of a polyester base and emulsion layers containing gelatin and light-sensitive silver halide crystals. Exposure to x-rays or light from intensifying screens causes a latent image in the crystals that is developed to produce the final image. Factors like contrast, speed, and spectral matching must be considered when selecting a film.
An X-ray film automatic processor is a device designed to move medical X-ray films from one solution to the next, in the film development process, without the need for human intervention except to insert a film or cassette
Intensifying screens are major component of the image receptor used in conventional radiography.Its function is to convert the X-rays into visible light through the process of fluorescence.
An X-ray film automatic processor is a device designed to move medical X-ray films from one solution to the next, in the film development process, without the need for human intervention except to insert a film or cassette
Intensifying screens are major component of the image receptor used in conventional radiography.Its function is to convert the X-rays into visible light through the process of fluorescence.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
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Surgical Site Infections, pathophysiology, and prevention.pptx
Radiographic film
1.
2. History
By the time x-rays were discovered, photography
was already an art.
Photographic film with a nitrocellulose base was
already being marketed by George Eastman.
3. The first x-rays were recorded on glass plates.
These were coated with emulsion on one side
only.
The exposure dose was quite high.
4. Glass plates were used until World war I.
During WWI, nitrocellulose based film was found
to be a more feasible choice for recording x-rays.
This film was single-emulsion.
5. It was later discovered that double-emulsion
responded to x-rays faster.
The flaw with nitrocellulose based film was its
easy flammability.
In 1924, cellulose acetate replaced the
nitrocellulose based film.
6. The Radiographic Film
A Radiographic film is similar in construction and
characteristics to a photographic film.
Its spectral response is different from
photographic film but its mechanism of
operation is the same.
7. The film is sandwiched between the radiographic
intensifying screens in a protective cassette.
The intensifying screens change the x-rays into
visible light. The visible light exposes the
radiographic film.
8. Film Structure
Radiographic Film has
two basic parts.
Base
Emulsion
Most films have two
layers of emulsion so
these are referred as
Double Emulsion Film.
9. An adhesive layer
attaches the emulsion
to the base.
The emulsion is
enclosed in a
protective layer of
gelatin called the
overcoat.
12. Transparent Base
Provides a surface and support for the
emulsion.
It must have strength, but it should be flexible.
Most film bases are composed of polyester.
13. Polyester can withstand higher temperatures
and is more fireproof.
The base is usually tinted blue to reduce light
glare.
Amount of tint varies per specifications of
different manufacturers.
14. Emulsion
The emulsion is the heart of the film.
The x-rays or light from the intensifying screens
interact with the emulsion and transfer
information to the film.
A homogeneous mixture of gelatin and silver
halide crystals and is about 3 to 5 µm thick.
15. Gelatin
The gelatin is clear so it transmits the light to the
silver halide crystals.
It is porous so the processing chemicals can
easily penetrate to the silver halide crystals.
The primary function of the gelatin is to provide
a support medium for the silver halide crystals by
holding them in place.
16. Silver Halide Crystals
98% Silver Bromide
2% Silver Iodide
May be
tabular,cubic,octahedr
al,polygonal in shape.
Tabular shape used
most commonly for
general radiography.
About 0.1µm thick and
1µm in diameter.
17. Silver Halide Crystals
The differences in speed, contrast and resolution
depends upon the process by which the silver
halide crystals are manufactured.
From the time the emulsion ingredients are
brought together until the film is packaged, the
whole process occurs in complete darkness.
18. The Latent Image
Invisible image produced on the film after
exposure prior to development.
The latent image is the invisible change in the
silver halide crystals.
The interaction between the photons and the
silver halide crystals produces the latent image.
19. The Latent Image Formation
This interaction is sometimes referred to as the
photographic effect.
This process is not well understood and is still
under research.
The Gurney-Mott theory is presently an
acceptable explanation of the photographic
effect.
20. Ionic structure of silver halide crystal
Bromide and iodide ions are mostly
concentrated on the surface of crystal giving it a
negative charge.
The silver ions are inside known as interstitial
silver ions,so inside is positively charged.
21. The Latent Image Formation
A Radiation interaction
releases electrons.
B Electrons migrate to
the sensitivity
center(contaminant in
the silver halide
crystal,usually silver
sulfide).
22. C At the sensitivity
centre, atomic silver is
formed by attracting an
interstitial silver ion---
latent image centre.
23. D The process is
repeated many times
resulting in the build up
of silver atoms.
E The remaining silver
halide is converted to
silver during
processing.
24. F The resulting silver
grain is formed.
Silver halide that is not
irradiated remain
inactive. The irradiated
and non-irradiated
silver halide produces
the latent image.
25. Types of Films
Screen films most commonly used.
Screen film used with intensifying screens.
Single emulsion- emulsion on one side of base.
Double emulsion used with two screens.
Direct exposure film or non-screen film.
Special purpose films
26. Standard screen-film sizes
English Units SI Units
7 x 7 in 18 x 18 cm
8 x 10 in 20 x 25 cm
10 x 12 in 24 x 30 cm
14 x 14 in 35 x 35 cm
14 x 17 in 35 x 43 cm
27. Screen Film Factors
Main factors to be considered when selecting
film
a) Contrast & Speed
b) Crossover
c) Spectral matching
d) Reciprocity Law
e) Safelights
28. Contrast
Contrast of a film depends on its latitude.
Latitude is the range of exposure techniques that
produce an acceptable image.
Latitude is inversely proportional to contrast.
29. High contrast film has low latitude
Medium contrast film has medium latitude
Low contrast film has high latitude
High contrast has small uniform grains
Low contrast has larger grains and wide range in
size.
30. Speed
It is the sensitivity of film to x-rays and light.
The size and shape of the silver halide crystals
are the main factors that determine speed.
Faster speed films are almost always double
emulsion.
Light spectrum from screens must match to
achieve optimum speed.
31. Crossover
Crossover is the
exposure of an
emulsion by light from
the opposite
radiographic
intensifying screen.
33. Crossover causes blurring of the image.
Can be reduced by
Tabular grains---flat, large surface area to vol
ratio
Addition of a light absorbing dye in crossover
control layer.
34. Spectral Matching
The most important consideration in selecting
screen film is spectral absorption matching.
The material in the screen will determine the
color of light emitted by the screen.
Special dyes in the film are used to match the
screen to the film.
35. Spectral Matching
Calcium Tungstate screens emit blue and blue
violet light.
Replaced by Rare earth screens.
Rare earth screens emit ultraviolet, blue, green
and red light.
36. Spectral Matching
If the light spectrum does not match, there will
be a significant loss of speed alongwith increased
patient dose.
37. Reciprocity Law
In radiography, it is generally assumed that the
total exposure of a film depends only on the total
quantity of radiation (mAs) and not on the
exposure time. This is known as the reciprocity
law.
Reciprocity law
Exposure=intensity x time
=Constant Optical Density
38. Reciprocity Law
The reciprocity law is true for film exposed
directly to x-rays.
It fails when film is exposed to light from
radiographic intensifying screens.
39. Reciprocity law failure is important when the
exposure times are very long (as in
mammography)or very short (angiography).
The result is a loss of speed.
.
40. Safelights
Working with film in
the darkroom requires
special lighting to
avoid exposure of the
film.
Filters are used to
avoid exposure of the
film.
41. Safelights
An amber filter can be used for blue sensitive
film only.
A red filter is used for blue-green sensitive film.
The color is not the only concern, the wattage of
the bulb and distance between the lamp and
work surface is also very important.
42. Special Film Types
Direct exposure film: used without intensifying
screen.
were used for small body parts.
Requires 10 to 100 times more exposure. The
emulsion is thicker than screen film.
Renders excellent detail. No longer used.
43. Single emulsion film: once used for extremities
but now most extremity cassettes are double
screen type.
Again required more exposure.
44. Mammography Film: Only single emulsion film
currently used in modern radiography.
Laser Film: Used in with a laser printer for digital
radiography, CT and MRI.
45. Subtraction Film: used in angiography to do
subtraction where the bone is removed for
better visualization of the arteries.
46. Spot film: Special roll film of 70 to 105 mm width
used in fluoroscopy.
Can be processed in x-ray film processor.
47. Cine film:
35 mm black & white film supplied in rolls of 100
and 500 ft
used in coronary angiography.
Requires motion picture film processor.
48. Handling and Storage of
Radiographic Film
X-ray film is a sensitive radiation detector and it
must be handled in an area free of radiation.
Film storage must be shielded.
The darkroom adjacent to the x-ray room
must be shielded.
49. Improper handling of the film will result in poor
image quality due to artifacts.
Avoid bending, creasing or rough handling of
the film.
Avoid sharp objects contacting the film.
50. Hands must be clean and dry.
Avoid hand creams, lotions or water free hand
cleaners.
Static electricity or a dirty processor can cause
artifacts.
51. Film is sensitive to heat and humidity.
Heat and humidity causes fog or a loss of
contrast.
Film should be stored at less than 20º C (68ºF)
Humidity should be between 40% and 60%.
52. Film must be handled and stored in the dark.
Low level diffuse light causes fog.
Bright light causes gross exposure.
Luminous watches, cell phone and darkroom
light leaks should be avoided.
53. Films should be used no longer than the stated
Shelf life.
The oldest film in stock should always be used
first.
Expired film results in loss of speed and contrast
and an increase in fog.