CONDENSATION ELASTOMERS LECTURE.pptx
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Condensation polysilicones are silicone rubbers based on condensation reactions that are used for dental impressions. They are available as two-paste or paste-liquid systems in various consistencies. The setting reaction is a condensation polymerization that occurs at room temperature between a base paste and reactor paste, involving tetraethyl orthosilicate and tin octate to form a crosslinked 3D polymer network with ethyl alcohol as a byproduct. They are manipulated by uniformly blending the pastes and liquids or kneading putty systems and are used for fixed partial denture, inlay, onlay, and implant impressions.
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Overall life span (LS) was 1671.7±1721.6 days and cumulative 5YS reached 62.4%, 10 years – 50.4%, 20 years – 44.6%. 94 LCP lived more than 5 years without cancer (LS=2958.6±1723.6 days), 22 – more than 10 years (LS=5571±1841.8 days). 67 LCP died because of LC (LS=471.9±344 days). AT significantly improved 5YS (68% vs. 53.7%) (P=0.028 by log-rank test). Cox modeling displayed that 5YS of LCP significantly depended on: N0-N12, T3-4, blood cell circuit, cell ratio factors (ratio between cancer cells-CC and blood cells subpopulations), LC cell dynamics, recalcification time, heparin tolerance, prothrombin index, protein, AT, procedure type (P=0.000-0.031). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and N0-12 (rank=1), thrombocytes/CC (rank=2), segmented neutrophils/CC (3), eosinophils/CC (4), erythrocytes/CC (5), healthy cells/CC (6), lymphocytes/CC (7), stick neutrophils/CC (8), leucocytes/CC (9), monocytes/CC (10). Correct prediction of 5YS was 100% by neural networks computing (error=0.000; area under ROC curve=1.0).
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
It includes regulation of combination products and medical devices. FDA and industry liaisons.
Post-Menstrual Smell- When to Suspect Vaginitis.pptx
Do you have abnormal smell after periods? It may be vaginitis. Do not worry, herbal medicine Fuyan Pill can help you get a cure.
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The Electrocardiogram - Physiologic Principles
These lecture slides, by Dr Sidra Arshad, offer a quick overview of the 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 lead (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
6. Describe the flow of current around the heart during the cardiac cycle
7. Discuss the placement and polarity of the leads of electrocardiograph
8. Describe the normal electrocardiograms recorded from the limb leads and explain the physiological basis of the different records that are obtained
9. Define mean electrical vector (axis) of the heart and give the normal range
10. Define the mean QRS vector
11. Describe the axes of leads (hexagonal reference system)
12. Comprehend the vectorial analysis of the normal ECG
13. Determine the mean electrical axis of the ventricular QRS and appreciate the mean axis deviation
14. Explain the concepts of current of injury, J point, and their significance
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. Chapter 3, Cardiology Explained, https://www.ncbi.nlm.nih.gov/books/NBK2214/
7. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Cell Therapy Expansion and Challenges in Autoimmune Disease
There is increasing confidence that cell therapies will soon play a role in the treatment of autoimmune disorders, but the extent of this impact remains to be seen. Early readouts on autologous CAR-Ts in lupus are encouraging, but manufacturing and cost limitations are likely to restrict access to highly refractory patients. Allogeneic CAR-Ts have the potential to broaden access to earlier lines of treatment due to their inherent cost benefits, however they will need to demonstrate comparable or improved efficacy to established modalities.
In addition to infrastructure and capacity constraints, CAR-Ts face a very different risk-benefit dynamic in autoimmune compared to oncology, highlighting the need for tolerable therapies with low adverse event risk. CAR-NK and Treg-based therapies are also being developed in certain autoimmune disorders and may demonstrate favorable safety profiles. Several novel non-cell therapies such as bispecific antibodies, nanobodies, and RNAi drugs, may also offer future alternative competitive solutions with variable value propositions.
Widespread adoption of cell therapies will not only require strong efficacy and safety data, but also adapted pricing and access strategies. At oncology-based price points, CAR-Ts are unlikely to achieve broad market access in autoimmune disorders, with eligible patient populations that are potentially orders of magnitude greater than the number of currently addressable cancer patients. Developers have made strides towards reducing cell therapy COGS while improving manufacturing efficiency, but payors will inevitably restrict access until more sustainable pricing is achieved.
Despite these headwinds, industry leaders and investors remain confident that cell therapies are poised to address significant unmet need in patients suffering from autoimmune disorders. However, the extent of this impact on the treatment landscape remains to be seen, as the industry rapidly approaches an inflection point.
TEST BANK For An Introduction to Brain and Behavior, 7th Edition by Bryan Kol...
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TEST BANK For An Introduction to Brain and Behavior, 7th Edition by Bryan Kolb, Ian Q. Whishaw, Verified Chapters 1 - 16, Complete Newest Version
TEST BANK For An Introduction to Brain and Behavior, 7th Edition by Bryan Kolb, Ian Q. Whishaw, Verified Chapters 1 - 16, Complete Newest VersionBest Ayurvedic medicine for Gas and Indigestion
Here is the updated list of Top Best Ayurvedic medicine for Gas and Indigestion and those are Gas-O-Go Syp for Dyspepsia | Lavizyme Syrup for Acidity | Yumzyme Hepatoprotective Capsules etc
Part II - Body Grief: Losing parts of ourselves and our identity before, duri...
Learn about body grief and ways to cope with it. We will also explore methods to heal from this challenging experience.
Role of Mukta Pishti in the Management of Hyperthyroidism
Muktapishti is a traditional Ayurvedic preparation made from Shoditha Mukta (Purified Pearl), is believed to help regulate thyroid function and reduce symptoms of hyperthyroidism due to its cooling and balancing properties. Clinical evidence on its efficacy remains limited, necessitating further research to validate its therapeutic benefits.
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptxHolistified Wellness
We’re talking about Vedic Meditation, a form of meditation that has been around for at least 5,000 years. Back then, the people who lived in the Indus Valley, now known as India and Pakistan, practised meditation as a fundamental part of daily life. This knowledge that has given us yoga and Ayurveda, was known as Veda, hence the name Vedic. And though there are some written records, the practice has been passed down verbally from generation to generation.Recently uploaded (20)
Does Over-Masturbation Contribute to Chronic Prostatitis.pptx
Does Over-Masturbation Contribute to Chronic Prostatitis.pptx
Local Advanced Lung Cancer: Artificial Intelligence, Synergetics, Complex Sys...
Local Advanced Lung Cancer: Artificial Intelligence, Synergetics, Complex Sys...
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
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Post-Menstrual Smell- When to Suspect Vaginitis.pptx
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
Ear and its clinical correlations By Dr. Rabia Inam Gandapore.pptx
Ear and its clinical correlations By Dr. Rabia Inam Gandapore.pptx
Cell Therapy Expansion and Challenges in Autoimmune Disease
Cell Therapy Expansion and Challenges in Autoimmune Disease
Tests for analysis of different pharmaceutical.pptx
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TEST BANK For An Introduction to Brain and Behavior, 7th Edition by Bryan Kol...
TEST BANK For An Introduction to Brain and Behavior, 7th Edition by Bryan Kol...
Part II - Body Grief: Losing parts of ourselves and our identity before, duri...
Part II - Body Grief: Losing parts of ourselves and our identity before, duri...
Role of Mukta Pishti in the Management of Hyperthyroidism
Role of Mukta Pishti in the Management of Hyperthyroidism
Vestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptx
Vestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptx
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
CONDENSATION ELASTOMERS LECTURE.pptx
- 2. Elastomers • Synthetic rubber based materials • No water involved in setting reaction NON-AQUEOUS ELASTOMERIC IMPRESSION MATERIALS
- 3. CLASSIFICATION OF ELASTOMERS BASED ON VISCOSITY/CONSISTENCY • LIGHT BODY • MEDIUM/REGULAR BODY • HEAVY BODY • PUTTY A/C TO POLYMERISATION • CONDENSATION POLYMERISATION- POLYSULFIDES , POLYSILICONES • ADDITION POLYMERISATION- ADDITION POLYSILICONE • IONIC RING OPENING POLYMERISATION- POLYETHER • VISIBLE LIGHT CURE POLYMERISATION- POLYETHER
- 4. CONDENSATION POLYSILICONES Are silicone rubbers based on condensation reactions. Not very popular these days due to advent of better elastomers.Also called RTV (Room temperature vulcanization )silicones. Available as two pastes or paste-liquid systems in low, medium,high or putty consistencies.
- 5. COMPOSITION
- 6. Setting reaction • It is a condensation reaction occurring at ambient temperature. BASE PASTE + REACTOR PASTE---- POLYMERISATION REACTION INVOLVING TETRA ETHYL ORTHOSILICATE IN PRESENCE OF TIN OCTATE ELASTOMER FORMS THROUGH CROSSLINKING BETWEEN TERMINAL SILICONE POLYMER AND ALKYL SILICATE GROUPS TO FORM 3D NETWORK ETHYL ALCOHOL – BY PRODUCT(Evaporation causes contraction of set silicone)
- 8. MANIPULATION • PASTE AND LIQUID- MIXING PAD…UNIFORM BLENDING • PUTTY AND LIQUID-KNEADED • TWO PASTES SYSTEM- MIXING PAD- VISCOSITY DIFFERENCES COMPENSATED
- 12. USES: • FIXED PARTIAL DENTURE IMPRESSIONS • INLAY,ONLAY IMPRESSIONS • IMPLANT IMPRESSIONS