Thursday, May 12, 2022

human body 🌶️

 

human body

By The Editors of Encyclopaedia Britannica • Edit History
Top Questions

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human body, the physical substance of the human organism, composed of living cells and extracellular materials and organized into tissues, organs, and systems.

human body; human anatomy
human body; human anatomy
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Human anatomy and physiology are treated in many different articles. For detailed discussions of specific tissues, organs, and systems, see human blood; cardiovascular system; digestive system, human; endocrine system, human; renal system; skin; human muscle system; nervous system; reproductive system, human; respiration, human; sensory reception, human; skeletal system, human. For a description of how the body develops, from conception through old age, see aging; growth; prenatal development; human development.

For detailed coverage of the body’s biochemical constituents, see protein; carbohydrate; lipid; nucleic acid; vitamin; and hormone. For information on the structure and function of the cells that constitute the body, see cell.

Many entries describe the body’s major structures. For example, see abdominal cavity; adrenal gland; aorta; bone; brain; ear; eye; heart; kidney; large intestine; lung; nose; ovary; pancreas; pituitary gland; small intestine; spinal cord; spleen; stomach; testis; thymus; thyroid gland; tooth; uterus; vertebral column.

Humans are, of course, animals—more particularly, members of the order Primates in the subphylum Vertebrata of the phylum Chordata. Like all chordates, the human animal has a bilaterally symmetrical body that is characterized at some point during its development by a dorsal supporting rod (the notochord), gill slits in the region of the pharynx, and a hollow dorsal nerve cord. Of these features, the first two are present only during the embryonic stage in the human; the notochord is replaced by the vertebral column, and the pharyngeal gill slits are lost completely. The dorsal nerve cord is the spinal cord in humans; it remains throughout life

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Tuesday, May 3, 2022

Angiography ♥️💚💙💕

 

https://www.heartandstroke.ca/

Heart

Angiography / arteriography

What is it?

An angiogram is a test that takes X-ray pictures of the coronary arteries and the vessels that supply blood to the heart. During an angiogram, a special dye is released into the coronary arteries from a catheter (special tube) inserted in a blood vessel. This dye makes the blood vessels visible when an X-ray is taken. Angiography allows doctors to clearly see how blood flows into the heart. This allows them to pinpoint problems with the coronary arteries.
Angiography may be recommended for patients with angina (chest pain) or those with suspected coronary artery disease (CAD). The test gives doctors valuable information on the condition of the coronary arteries, such as atherosclerosis, regurgitation (blood flowing backwards through the heart valves) or pooling of blood in a chamber because of a valve malfunction.


What to expect?

Angiography is performed in a hospital or clinic. You will be asked to lie on a table, and the site where the catheter is to be inserted (the groin or arm) will be cleaned. You will be given a local anesthetic to numb the skin so you feel no pain. Then, a catheter is carefully guided through a vein or artery to a position near the heart. When the catheter is in place, it releases a special dye into the bloodstream. While the dye is being released, you might feel a brief sensation of heat, which usually passes quickly. An angiogram can take about one to two hours. However, it is best to check with the centre where you are having the procedure to find out how long it will take.

Angiography is a very common procedure and is generally considered safe. In some patients, the contrast dye may cause nausea, the need to urinate or even allergic reactions, although these side effects are rare.

How to prepare

Generally, you should not eat or drink for 6 to 8 hours before having a coronary angiography. Speak to your doctor about how to prepare for the test, specifically about food, drink and medications. If you have questions, it is best to check with the centre where you are having your test for specific information about how to prepare

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Sunday, April 17, 2022

How Eyes Work


 

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How the Heart Woeks


 

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Saturday, March 26, 2022

AED.. Defibrillator 📌


 

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Saturday, March 12, 2022

CPR 🍎🔥

 CPR 🔥🌶️

https://en.m.wikipedia.org/wiki/Cardiopulmonary_resuscitation

Cardiopulmonary resuscitation (CPR) is an emergency procedure consisting of chest compressions often combined with artificial ventilation in an effort to manually preserve intact brain function until further measures are taken to restore spontaneous blood circulation and breathing in a person who is in cardiac arrest. It is recommended in those who are unresponsive with no breathing or abnormal breathing, for example, agonal respirations.[1]

Cardiopulmonary resuscitation
CPR training-04.jpg
CPR being performed on a medical-training mannequin
SpecialtyCardiology
ICD-999.60
MeSHD016887
OPS-301 code8-771
MedlinePlus000010

CPR involves chest compressions for adults between 5 cm (2.0 in) and 6 cm (2.4 in) deep and at a rate of at least 100 to 120 per minute.[2] The rescuer may also provide artificial ventilation by either exhaling air into the subject's mouth or nose (mouth-to-mouth resuscitation) or using a device that pushes air into the subject's lungs (mechanical ventilation). Current recommendations place emphasis on early and high-quality chest compressions over artificial ventilation; a simplified CPR method involving only chest compressions is recommended for untrained rescuers.[3] In children, however, only doing compressions may result in worse outcomes because, in children, the problem normally arises from a respiratory, rather than cardiac, problems.[1] Chest compression to breathing ratios is set at 30 to 2 in adults.

CPR alone is unlikely to restart the heart. Its main purpose is to restore partial flow of oxygenated blood to the brain and heart. The objective is to delay tissue death and to extend the brief window of opportunity for a successful resuscitation without permanent brain damage. Administration of an electric shock to the subject's heart, termed defibrillation, is usually needed in order to restore a viable, or "perfusing", heart rhythm. Defibrillation is effective only for certain heart rhythms, namely ventricular fibrillation or pulseless ventricular tachycardia, rather than asystole or pulseless electrical activity, which usually require the treatment of underlying conditions to restore cardiac function. Early shock, when appropriate, is recommended. CPR may succeed in inducing a heart rhythm that may be shockable. In general, CPR is continued until the person has a return of spontaneous circulation (ROSC) or is declared dead.[4]

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Monday, February 21, 2022

Sleep 💙💚


 

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Tuesday, February 15, 2022

What Is Visual Acuity? - Definition, Scale & Tests

 ttps://study.com/academy/lesson/what-is-visual-acuity-definition-scale-tests.html


What Is Visual Acuity? - Definition, Scale & Tests.



What Is Visual Acuity? - Definition, Scale & Tests

Instructor: Danielle Haak
Visual acuity is a measure of how clear and sharp your vision is. To standardize this, it's measured at different distances so that the results from many people can be averaged together. This lesson will explain visual acuity and the different tests used to measure it.

What Is Visual Acuity?

Have you ever stood in a doctor's office and had to read from a small chart across the room? Usually there's a large letter 'E' at the top, and as you move down the chart, each row of letters gets smaller and smaller. The doctor might have you repeat this exercise many times, covering one eye or reading it with both eyes open.

This particular chart is called a Snellen chart, and it is one test used to measure visual acuity. Visual acuity refers to how sharp or clear your vision is. Each time you see an eye doctor, called an ophthalmologist or optometrist, they are measuring your visual acuity.

A standard Snellen chart, with vision estimates.
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Measuring Visual Acuity

Once you read a Snellen chart, how does the doctor know what to do with the results? Well, the results are usually compared to a standard called 20/20 vision. If you have 20/20 vision, it means that, at a distance of 20 feet, you can see things as clear as the average person. Obviously, this is a slightly subjective process, but it allows the vision of different people to be approximately compared to a scale.

As you might be familiar with, sometimes a person's vision changes from this 20/20 standard. If you can see things at a distance very clearly, but have trouble focusing on things close to you like the text of a book, you have hyperopia , also called farsightedness. Conversely, if you can see things up close clearly but can't focus on objects that are at a distance, you have myopia, also called nearsightedness. Sometimes people may have trouble focusing on things that are both near and far.

By analyzing your visual acuity, a doctor can estimate how sharp your vision is and then adjust it with the use of corrective lenses to help bring you back to the 20/20 standard.

Snellen Chart Examples

Let's take a look at the Snellen chart above. On the left of the chart, you can see each row of letters that get smaller and smaller as you move down the chart. The lines are numbered, and then there's a number similar to 20/20 on the right. How does this work?

The doctor's office will have a spot marked on the floor where you are to stand to complete the exercise. You will probably cover one eye and then begin reading down the chart as far as you can, until the letters become too small to read. With this chart, if you can read through line 8 without any problems, you have 20/20 vision. Congratulations! That's the standard we talked about above.

However, if you can only read through line 4, you have 20/50 vision. What does that mean? A measure of 20/50 vision means you have to stand at a distance of 20 feet to read what most people can read from 50 feet. This is one version of nearsightedness; you have a harder time seeing things farther away.

What if you can only read the top line? Well, this means your visual acuity measure is 20/200. You have to stand at a distance of 20 feet to see what most people can see from 200 feet away! That means you are even more nearsighted than the person with a visual acuity measure of 20/50.

But wait, the Snellen chart we have here has 11 lines - what if a person can clearly read all the way through line 11? This means their visual acuity is better than 20/20. Though there aren't numbers listed here, it might be something like 20/10, meaning they can stand at 20 feet and see something clearly that most people have to be 10 feet closer to see. That's some good visual acuity!

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