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Urorectal Septum
The urorectal septum is an invagination of the cloaca. It divides it into a dorsal part (the hindgut) and a ventral part (the urogenital sinus). It invaginates from cranial to caudal, formed from the endodermal cloaca, and fuses with the cloacal membrane. Malformations can cause fistulas. Structure The urorectal septum is an embryonic structure formed from an invagination of the cloaca. The urorectal septum divides the cloaca into two parts: * a dorsal part, forming part of the hindgut, which forms the rectum and the anus. * a ventral part, forming the urogenital sinus, which forms the allantois, which becomes the urinary bladder. The urorectal septum becomes part of the perineal body, helping to form the perineum. Development The urorectal septum develops from cranial to caudal, and is flat in the coronal plane. It is formed from endoderm, the same germ layer as the cloaca. It fuses with the cloacal membrane. Clinical significance Urorectal septum malformation Mal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloaca
In animal anatomy, a cloaca ( ), plural cloacae ( or ), is the posterior orifice that serves as the only opening for the digestive, reproductive, and urinary tracts (if present) of many vertebrate animals. All amphibians, reptiles and birds, and a few mammals ( monotremes, tenrecs, golden moles, and marsupial moles), have this orifice, from which they excrete both urine and feces; this is in contrast to most placental mammals, which have two or three separate orifices for evacuation. Excretory openings with analogous purpose in some invertebrates are also sometimes referred to as cloacae. Mating through the cloaca is known as cloacal copulation, commonly referred to as cloacal kiss. The cloacal region is also often associated with a secretory organ, the cloacal gland, which has been implicated in the scent-marking behavior of some reptiles, marsupials, amphibians, and monotremes. Etymology The word is from the Latin verb ''cluo'', "(I) cleanse", thus the noun ''cloaca'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronal Plane
The coronal plane (also known as the frontal plane) is an anatomical plane that divides the body into dorsal and ventral sections. It is perpendicular to the sagittal and transverse planes. Details The coronal plane is an example of a longitudinal plane. For a human, the mid-coronal plane would transect a standing body into two halves (front and back, or anterior and posterior) in an imaginary line that cuts through both shoulders. The description of the coronal plane applies to most animals as well as humans even though humans walk upright and the various planes are usually shown in the vertical orientation. The sternal plane (''planum sternale'') is a coronal plane which transects the front of the sternum. Etymology The term is derived from Latin ''corona'' ('garland, crown'), from Ancient Greek κορώνη (''korōnē'', 'garland, wreath'). The coronal plane is so-called because it lies in the direction of Coronal suture. Additional images File:Coronal plane CT scan of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetralogy Of Fallot
Tetralogy of Fallot (TOF), formerly known as Steno-Fallot tetralogy, is a congenital heart defect characterized by four specific cardiac defects. Classically, the four defects are: *pulmonary stenosis, which is narrowing of the exit from the right ventricle; * a ventricular septal defect, which is a hole allowing blood to flow between the two ventricles; * right ventricular hypertrophy, which is thickening of the right ventricular muscle; and * an overriding aorta, which is where the aorta expands to allow blood from both ventricles to enter. At birth, children may be asymptomatic or present with many severe symptoms. Later in infancy, there are typically episodes of bluish colour to the skin due to a lack of sufficient oxygenation, known as cyanosis. When affected babies cry or have a bowel movement, they may undergo a "tet spell" where they turn cyanotic, have difficulty breathing, become limp, and occasionally lose consciousness. Other symptoms may include a heart murmur, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventricular Septal Defect
A ventricular septal defect (VSD) is a defect in the ventricular septum, the wall dividing the left and right ventricles of the heart. The extent of the opening may vary from pin size to complete absence of the ventricular septum, creating one common ventricle. The ventricular septum consists of an inferior muscular and superior membranous portion and is extensively innervated with conducting cardiomyocytes. The membranous portion, which is close to the atrioventricular node, is most commonly affected in adults and older children in the United States. It is also the type that will most commonly require surgical intervention, comprising over 80% of cases. Membranous ventricular septal defects are more common than muscular ventricular septal defects, and are the most common congenital cardiac anomaly. Signs and symptoms Ventricular septal defect is usually symptomless at birth. It usually manifests a few weeks after birth. VSD is an acyanotic congenital heart defect, aka a lef ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atrial Septal Defect
Atrial septal defect (ASD) is a congenital heart defect in which blood flows between the atria (upper chambers) of the heart. Some flow is a normal condition both pre-birth and immediately post-birth via the foramen ovale; however, when this does not naturally close after birth it is referred to as a patent (open) foramen ovale (PFO). It is common in patients with a congenital atrial septal aneurysm (ASA). After PFO closure the atria normally are separated by a dividing wall, the interatrial septum. If this septum is defective or absent, then oxygen-rich blood can flow directly from the left side of the heart to mix with the oxygen-poor blood in the right side of the heart; or the opposite, depending on whether the left or right atrium has the higher blood pressure. In the absence of other heart defects, the left atrium has the higher pressure. This can lead to lower-than-normal oxygen levels in the arterial blood that supplies the brain, organs, and tissues. However, an ASD m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deafness
Deafness has varying definitions in cultural and medical contexts. In medical contexts, the meaning of deafness is hearing loss that precludes a person from understanding spoken language, an audiological condition. In this context it is written with a lower case ''d''. It later came to be used in a cultural context to refer to those who primarily communicate through sign language regardless of hearing ability, often capitalized as ''Deaf'' and referred to as "big D Deaf" in speech and sign. The two definitions overlap but are not identical, as hearing loss includes cases that are not severe enough to impact spoken language comprehension, while cultural Deafness includes hearing people who use sign language, such as children of deaf adults. Medical context In a medical context, deafness is defined as a degree of hearing difference such that a person is unable to understand speech, even in the presence of amplification. In profound deafness, even the highest intensity sound ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spina Bifida
Spina bifida (Latin for 'split spine'; SB) is a birth defect in which there is incomplete closing of the spine and the membranes around the spinal cord during early development in pregnancy. There are three main types: spina bifida occulta, meningocele and myelomeningocele. Meningocele and myelomeningocele may be grouped as spina bifida cystica. The most common location is the lower back, but in rare cases it may be in the middle back or neck. Occulta has no or only mild signs, which may include a hairy patch, dimple, dark spot or swelling on the back at the site of the gap in the spine. Meningocele typically causes mild problems, with a sac of fluid present at the gap in the spine. Myelomeningocele, also known as open spina bifida, is the most severe form. Problems associated with this form include poor ability to walk, impaired bladder or bowel control, accumulation of fluid in the brain (hydrocephalus), a tethered spinal cord and latex allergy. Learning problems are rela ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birth Defect
A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can range from mild to severe. Birth defects are divided into two main types: structural disorders in which problems are seen with the shape of a body part and functional disorders in which problems exist with how a body part works. Functional disorders include metabolic and degenerative disorders. Some birth defects include both structural and functional disorders. Birth defects may result from genetic or chromosomal disorders, exposure to certain medications or chemicals, or certain infections during pregnancy. Risk factors include folate deficiency, drinking alcohol or smoking during pregnancy, poorly controlled diabetes, and a mother over the age of 35 years old. Many are believed to involve multiple factors. Birth defects may be visi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ureter
The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In a human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional epithelium, and has an additional smooth muscle layer that assists with peristalsis in its lowest third. The ureters can be affected by a number of diseases, including urinary tract infections and kidney stone. is when a ureter is narrowed, due to for example chronic inflammation. Congenital abnormalities that affect the ureters can include the development of two ureters on the same side or abnormally placed ureters. Additionally, reflux of urine from the bladder back up the ureters is a condition commonly seen in children. The ureters have been identified for at least two thousand years, with the word "ureter" stemming from the stem relating to urinating and seen in written records since at least the time of Hippocrates. It is, however, on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicornuate Uterus
A bicornuate uterus or bicornate uterus (from the Latin ''cornū'', meaning "horn"), is a type of mullerian anomaly in the human uterus, where there is a deep indentation at the fundus (top) of the uterus. Pathophysiology A bicornuate uterus develops during embryogenesis. It occurs when the proximal (upper) portions of the paramesonephric ducts do not fuse, but the distal portions that develops into the lower uterine segment, cervix, and upper vagina fuse normally. Diagnosis Diagnosis of bicornuate uterus typically involves imaging of the uterus with 2D or 3D ultrasound, hysterosalpingography, or magnetic resonance imaging (MRI). On imaging, a bicornuate uterus can be distinguished from a septate uterus by the angle between the cornua (intercornual angle): less than 75 degrees in a septate uterus, and greater than 105 degrees in a bicornuate uterus. Measuring the depth of the cleft between the cornua (fundal cleft) may also assist in diagnosis; a cleft of over is indicativ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uterus
The uterus (from Latin ''uterus'', plural ''uteri'') or womb () is the organ in the reproductive system of most female mammals, including humans that accommodates the embryonic and fetal development of one or more embryos until birth. The uterus is a hormone-responsive sex organ that contains glands in its lining that secrete uterine milk for embryonic nourishment. In the human, the lower end of the uterus, is a narrow part known as the isthmus that connects to the cervix, leading to the vagina. The upper end, the body of the uterus, is connected to the fallopian tubes, at the uterine horns, and the rounded part above the openings to the fallopian tubes is the fundus. The connection of the uterine cavity with a fallopian tube is called the uterotubal junction. The fertilized egg is carried to the uterus along the fallopian tube. It will have divided on its journey to form a blastocyst that will implant itself into the lining of the uterus – the endometrium, where it will ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vagina
In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen. At the deep end, the cervix (neck of the uterus) bulges into the vagina. The vagina allows for sexual intercourse and birth. It also channels menstrual flow, which occurs in humans and closely related primates as part of the menstrual cycle. Although research on the vagina is especially lacking for different animals, its location, structure and size are documented as varying among species. Female mammals usually have two external openings in the vulva; these are the urethral opening for the urinary tract and the vaginal opening for the genital tract. This is different from male mammals, who usually have a single urethral opening for both urination and reproduction. The vaginal opening is much larger than the nearby urethral opening, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
