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One of the most common parasites to infect human beings is the yeast-like Blastocystis hominis, a single-celled parasitic organism that causes abdominal cramping, bloating, gas, and sometimes anal itching. Other common parasites are: Tapeworms, which can grow as long as 60 feet while living in the human intestines.
Carotid artery stenosis can be caused by cholesterol build-up in the blood vessels (atherosclerosis). Blood clots can form in this area and travel up to the brain. This condition may be present for a long time before symptoms appear. When symptoms do occur, stroke or brief stroke-like attacks are common. If this condition is discovered as a result of a stroke or stroke-like attack, cholesterol lowering medications and blood thinners may be used to improve blood flow to the brain. If the degree of narrowing is severe, surgery may be needed to open the blood vessel.
Minimally invasive surgery has been shown to be feasible and safe in pediatric patients since 1975 when laparoscopic surgery was first used to treat a small bowel obstruction. Laparoscopy is an option for surgical repair of inguinal hernias in addition to the traditional open approach.
The inflatable penile prosthesis consists of two attached cylinders -- a reservoir and a pump -- which are placed surgically in the body. The two cylinders are inserted in the penis and connected by tubing to a separate reservoir of saline. The reservoir is implanted under the rectus muscles in the lower abdomen. The Coloplast Titan Touch inflatable penile prosthesis is a self-contained, fluid-filled system made from Bioflex and silicone.
Pregnancy ultrasounds are performed mainly using transabdominal ultrasound. For many women, especially after 8 weeks gestation, sufficient information about the baby may be obtained with transabdominal ultrasound only. However, in the early pregnancy, the developing embryo is very small (at 6 weeks gestation, the baby is only 5-9mm long) and a transvaginal ultrasound may be required to get a better image of the baby. Transvaginal ultrasound is safe and commonly performed during all stages of pregnancy, including the first trimester. It will not harm you or your baby.
Anemia is a medical condition in which the red blood cell count or hemoglobin is less than normal. The normal level of hemoglobin is generally different in males and females. For men, a normal hemoglobin level is typically defined as a level of more than 13.5 gram/100 ml, and in women as hemoglobin of more than 12.0 gram/100 ml. These definitions may vary slightly depending on the source and the laboratory reference used. Continue Reading
Binding and Fusion: HIV begins its life cycle
when it binds to a CD4 receptor and one of two
co-receptors on the surface of a CD4+
Tlymphocyte. The virus then fuses with the host
cell. After fusion, the virus releases RNA, its
genetic material, into the host cell.
Reverse Transcription: An HIV enzyme
called reverse transcriptase converts the singlestranded HIV RNA to double-stranded HIV DNA.
Integration: The newly formed HIV DNA
enters the host cell's nucleus, where an HIV
enzyme called integrase "hides" the HIV DNA
within the host cell's own DNA. The integrated
HIV DNA is called provirus. The provirus may
remain inactive for several years, producing few or
no new copies of HIV
Transcription: When the host cell receives a
signal to become active, the provirus uses a host
enzyme called RNA polymerase to create copies of
the HIV genomic material, as well as shorter
strands of RNA called messenger RNA (mRNA).
The mRNA is used as a blueprint to make long
chains of HIV proteins.
Assembly: An HIV enzyme called protease cuts
the long chains of HIV proteins into smaller
individual proteins. As the smaller HIV proteins
come together with copies of HIV's RNA genetic
material, a new virus particle is assembled.
Budding: The newly assembled virus pushes out
("buds") from the host cell. During budding, the new
virus steals part of the cell's outer envelope. This
envelope, which acts as a covering, is studded with
protein/sugar combinations called HIV
glycoproteins. These HIV glycoproteins are
necessary for the virus to bind CD4 and coreceptors. The new copies of HIV can now move
on to infect other cells.
This video: Patent ductus arteriosus (PDA) is a persistent opening between two major blood vessels leading from the heart. The opening, called the ductus arteriosus, is a normal part of a baby's circulatory system before birth that usually closes shortly after birth. If it remains open, however, it's called a patent ductus arteriosus. A small patent ductus arteriosus often doesn't cause problems and might never need treatment. However, a large patent ductus arteriosus left untreated can allow poorly oxygenated blood to flow in the wrong direction, weakening the heart muscle and causing heart failure and other complications. Treatment options for a patent ductus arteriosus include monitoring, medications and closure by cardiac catheterization or surgery.