bilaminar embryonic disc dorsal and ventraldorsal→epiblast
ventral→hypoblast embryology Mar 31, 2019, 6:14 AM HirotoShishido
Meckel diverticulum characteristicsrules of 2s
2 inches long(about 5cm)
2 feet (61cm) proximal to the ileocecal valve
occurs 2% of the population
2:1=male:female
often occurs 2 years of age(60%)
contain 2 types of epithelium(gastric,pancreatic) gastrointestinalembryology Mar 29, 2019, 4:10 AM HirotoShishido
thyroid
embryologythyroid arises from floor of primitive pharynx and descends into neck through thyroglossal duct embryologyendocrinology Jun 29, 2019, 7:31 AM HirotoShishido
What is pituitary gland derived from?anterior(adenohypophysis)→ectoderm(Rathke pouch)
how the splitting timing affect the type of identical twinsDD→split occurs within 2,3days following the fertization
MD→3〜8days
DD→8〜13days reproductiveembryologyOBGY Apr 6, 2019, 12:40 AM HirotoShishido
when are amnion and yolk sac formed?day8 epiblasts migrate and form amnion
day9 hypoblast migrate and form yolk sac embryology Apr 5, 2019, 11:17 PM HirotoShishido
muscular system development
which muscle does the tissue in abaxial domain and primaxial domain develop into respectivelyprimaxial ←from somites
→back,shoulder and intercoastal muscles
Pierre Robin sequencemicrognathia, glossoptosis, cleft palate, airway obstruction(☆improve with prone position)
☆A sequence occurs when a single developmental defect causes a cascade of additional malformations. embryologypediatricsUWorld May 13, 2020, 10:15 PM HirotoShishido
the most common type of tracheoesophageal anomaliesesophageal atresia(EA)with distal tracheoesophageal fistula(TEF) is the most common(85%) gastrointestinalembryology Mar 30, 2019, 1:33 AM HirotoShishido
fetal erythropoeiesisYolk sac (3–8 weeks)
Liver (6 weeks–birth)
Spleen (10–28 weeks)
Bone marrow (18 weeks to adult) hematologyembryology Jul 1, 2020, 8:25 AM HirotoShishido
origins of meningesDura mater— Derived from mesoderm.
Arachnoid mater— Derived from neural
crest.
urachus and malignancyyolk sac forms the allantois(尿膜)
→allantoins become the urachus(尿膜管)(duct between bladder and umbilicus)
→urachus which fails to involute may increase the risk of infection,malignancy(eg,adenocarcinoma) embryology Mar 30, 2019, 12:36 AM HirotoShishido
