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Ovarian Cancer
Ovarian Cancer samer kareem 3,760 Views • 3 years ago

Ovarian cancer warning signs include ongoing pain or cramps in the belly or back, abnormal vaginal bleeding, nausea, and bloating. Depending on the cancer stage, ovarian cancer treatment includes surgery and chemotherapy.

Approach to Hypokalemia
Approach to Hypokalemia samer kareem 1,223 Views • 3 years ago

A step by step approach to Hypokalaemia including causes, diagnosis and management.

How to do an Insulin Injection
How to do an Insulin Injection samer kareem 8,901 Views • 3 years ago

Insert the needle into the rubber stopper of the insulin bottle. Push the plunger down to inject air into the bottle (this allows the insulin to be drawn more easily). Leave the needle in the bottle. Turn the bottle and syringe upside-down.

Total Parotidectomy
Total Parotidectomy samer kareem 2,371 Views • 3 years ago

This video show the steps in a total parotidectomy with VII nerve preservation. The patient had a malignant parotid tumor without VII nerve compromise.

Artificial Kidney Transplant
Artificial Kidney Transplant samer kareem 6,523 Views • 3 years ago

Artificial kidney is often a synonym for hemodialysis, but may also, more generally, refer to renal replacement therapies (with exclusion of kidney transplantation) that are in use and/or in development.

From axons to tracts
From axons to tracts Mohamed 21,086 Views • 3 years ago

The complex circuitry interconnecting different areas in the brain, known collectively as white matter, is composed of millions of axons organized into fascicles and bundles. Upon macroscopic examination of sections of the brain, it is difficult to discern the orientation of the fibers. The same is true for conventional imaging modalities. However, recent advancements in magnetic resonance imaging (MRI) make such task possible in a live subject. By sensitizing an otherwise typical MRI sequence to the diffusion of water molecules it is possible to measure their diffusion coefficient in a given direction1. Normally, the axonal membrane and myelin sheaths pose barriers to the movement of water molecules and, thus, they diffuse preferentially along the axon2. Therefore, the direction of white matter bundles can be elucidated by determining the principal diffusivity of water. The three-dimensional representation of the diffusion coefficient can be given by a tensor and its mathematical decomposition provides the direction of the tracts3; this MRI technique is known as diffusion tensor imaging (DTI). By connecting the information acquired with DTI, three-dimensional depictions of white matter fascicles are obtained4. The virtual dissection of white matter bundles is rapidly becoming a valuable tool in clinical research.

Our journey begins with a transverse section of tightly packed axons as seen through light microscopy. Although represented as a two-dimensional "slice", we see that these axons in fact resemble tubes. A simulation of water molecules diffusing randomly inside the axons demonstrates how the membranes and myelin hinder their movement across them and shows the preferred diffusion direction --along the axons. The tracts depicted through DTI slowly blend in and we ride along with them. As we zoom out even more, we realize that it is a portion of the corpus callosum connecting the two sides of the brain we were traveling on and the great difference in relative scale of the individual axons becomes evident. The surface of the brain is then shown, as well as the rest of the white matter bundles--a big, apparently chaotic tangle of wires. Finally, the skin covers the brain.

With the exception of the simulated water molecules, all the data presented in the animation is obtained through microscopy and MRI. Computer algorithms for the extraction of the cerebral structures and a custom-built graphics engine make our journey through the brain's anatomy possible in a living person.

Micrograph courtesy of Dr. Christian Beaulieu, University of Alberta.
Music by Mario Mattioli.

References:
1. Stejskal, E.O., et al., J. Chem. Phys., 1965. 42:
2. Beaulieu, C., NMR Biomed., 2002. 15:435-55.
3. Basser, P.J., et al., J. Magn. Reson. B, 1994. 103:247-54.
4. Mori, S., et al., NMR Biomed., 2002. 15:468-80.

Laparoscopic Appendectomy Steps
Laparoscopic Appendectomy Steps Doctor 14,298 Views • 3 years ago

Laparoscopic Appendectomy for Acute Appendicitis Post-illeal Appendix

Laparoscopic Varicocelectomy
Laparoscopic Varicocelectomy Doctor 25,868 Views • 3 years ago

16 year Boy.Grade III Varicocele.ISV reflux on CDUS.Operative findings showed high attachment of sigmoid.This procedure was done at Pakistan Institute of Medical sciences,PIMS,Islamabad,Pakistan

Exam- COPD Patient
Exam- COPD Patient samer kareem 1,761 Views • 3 years ago

Exam- COPD Patient

Laser Dental Surgery HD
Laser Dental Surgery HD Scott Stevens 6,423 Views • 3 years ago

Laser Dental Surgery HD

Acute Stroke Intervention
Acute Stroke Intervention samer kareem 4,679 Views • 3 years ago

Narrated animation of stroke intervention. Video supplied by Covidien, showing the Solitaire mechanical thrombectomy device, which was the first FDA-approved device for such an indication.

Vaginal Hysterectomy using Thermal Hemostasis
Vaginal Hysterectomy using Thermal Hemostasis Medical_Videos 7,862 Views • 3 years ago

Vaginal Hysterectomy using Thermal Hemostasis

AZT Mechanism of Antiviral Activity
AZT Mechanism of Antiviral Activity Medical_Videos 8,236 Views • 3 years ago

AZT Mechanism of Antiviral Activity

Anatomy of The Shoulder and Arm Muscles
Anatomy of The Shoulder and Arm Muscles Anatomy_Videos 18,400 Views • 3 years ago

Anatomy of The Shoulder and Arm Muscles

How long does it take for your skin to grow back ?
How long does it take for your skin to grow back ? samer kareem 9,634 Views • 3 years ago

Throughout your life, your skin will change constantly, for better or worse. In fact, your skin will regenerate itself approximately every 27 days. Proper skin care is essential to maintaining the health and vitality of this protective organ.

Histology of Aorta
Histology of Aorta Histology 5,912 Views • 3 years ago

Histology of Aorta

How surgeons remove kidney stones
How surgeons remove kidney stones Ayman Kamol 1,381 Views • 3 years ago

How surgeons remove kidney stones كيف يقوم الجراحون بإزالة حصى الكلى see more http://www.kidneymy.com/

Preeclampsia
Preeclampsia samer kareem 3,958 Views • 3 years ago

Formerly called toxemia, preeclampsia is a condition that pregnant women develop. It is marked by high blood pressure in women who have previously not experienced high blood pressure before. Preeclamptic women will have a high level of protein in their urine and often also have swelling in the feet, legs, and hands. This condition usually appears late in pregnancy, generally after the 20 week mark, although it can occur earlier

Histology of Spleen
Histology of Spleen Histology 7,194 Views • 3 years ago

Histology of Spleen

Sneezingng mechanismIn
Sneezingng mechanismIn samer kareem 1,461 Views • 3 years ago

A sneeze, or sternutation, is a semi-autonomous, convulsive expulsion of air from the lungs through the nose and mouth, usually caused by foreign particles irritating the nasal mucosa

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