uWorld 7 Flashcards
what is a distinct histopathologic manifestation of chronic hepatitis B
accumulation of HEPATITIS B SURFACE ANTIGEN within infected cytoplasm
appears as FINELY GRANULAR, HOMOGENOUS, DULL EOSINOPHILIC INCLUSION that fill the cytoplasm (ground glass hepatocytes)
hepatocyte necrosis (ballooning degeneration), apoptosis, steatosis, portal inflammation with mononuclear inclusions (lymphocytes, macrophages)
what is seen in a liver infected with chronic hep C
lymphoid aggregates within portal tracts and focal areas of macrovesicular steatosis
progesterone only pill and levonorgestrel intrauterine device prevent pregnancy how
thickening cervical mucus preventing sperm from accessing the uterus
how do copper IUDs prevent pregnancy
copper ions elicit an inflammatory reaction in the uterus that is toxic to sperm and prevents fertilization
anti-mitochondrial antibodies are seen in whom
primary biliary cirrhosis
anti-centromere antibodies are found in whom
CREST syndrome
what part of the sarcomere only has thick (myosin) filaments
H-band (portion of A band that straddles the M line- which looks like two white lines on EM)
what part of the sarcomere is always the same length
what parts decrease in length during contraction
A band- corresponds to the thick filaments but includes where they overlap the thin (actin) filaments
H band and I band decrease in length during contraction
what part of the sarcomere contains only thin filaments and what makes up the thin filaments
I band which contains the Z line (typically distinctly darker than the reminder of the sarcomere)
Z-line is anchor for thin filaments (actin, tropomyosin, troponin)
what are the promoter sequences of eukaryotes
TATA (Hogness) box- 25 bp upstream for gene
CAAT box- 70 to 80 bp upstream of the gene
Ehlers danlos is due to a what kind of problem
college synthesis- DEFICICENY in PROCOLLAGEN PEPTIDASE- enzyme that cleaves terminal N and C pro peptides from procallagen in the extacellulat space
collagen DOES NOT PROERPLY CROSSLINK
how do corticosteroids (bethamethasone, dexamethasone) increase surfactant production
accelerating maturation of type II pneumocytes
at risk pregnancies for preterm birth, antenatal administration of magnesium sulfate has been shown to decrease risk for what
cerebral palsy
vesicles on the lips and hard palate with fever and lymphadenopathy is characteristic of what
gingivostomatitis (gums and hard palate are KEY)
(recurrent lesions are not as severe due to existing cellular and humoral immunity)
KEEP IN MIND: hand foot mouth is SOFT PALATE, buccal mucosa, tongue
what is seen on Tzanc smear of HSV
multinucleate giant cells and intranuclear inclusion bodies
dihydrorhodamine flow pyrometry testing revealing absence of the teen fluorescence that is characteristic of normal neutrophils is suggestive of what
Chronic Granulomatous Disease (NADPH oxidase deficiency)
X-linked mutation
how do mu opioid receptors work
G protein-linked that activate secondary messenger pathways
POTASSIUM CONDUCTANCE is a major pathway- hyper polarizing postsynaptic neurons and termination of pain transmission
also can inhibit adenylate cyclase, calcium conductance, and transmitter release
what is believed to be the primary causes of lacunar infarcts
lipohyalinosis and microatheromas (result form atherosclerotic accumulation of lipid-laden macrophages within the intimal later of penetration artery near its origin off the parent vessel)
these changes predispose to small-vessel occlusion and infra of the CNS with liquefactive necrosis