Physiology Flashcards
mechanism for PTH
1) work via its R on osteoblasts by indirect mechanism ⟹ increase RANK ligand, M-CSF ⟹ osteoclast presursor diff into mature ⟹ bone reabsorption
2) inhibits the release of osteoprotegrin (a decoy for RANK ligand receptor, which impeded the RANK interaction)
net result for PTH: Ca2+ re-absorption, urine excretion of P
function of calcitonin
made by thyroid gland; inhibits osteoclast, decrease bone reabsorption, increase bone mineral density;
effect opposite to PTH
ECG presentation for AF?
No P-wave (no regular atrial contraction); replaced by “f-wave” (fibrillatory)
narrow QRS wave, inregular R-R interval
In AF, the determinant for ventricular contraction rate is the AV node refractory period
Kartagener’s syn
microtubular dynein arm defect: immotile cilia
infertility, recurrent sinusitis, bronchiectasis
卡特在戛纳：不孕症
cardiac abnormality associated with Downs?
ASD
failure of the endocardial cushions of the AV canal to fuse completely ; patients usually also have cleft in the anterior MV and in the septal leaflet of the TV ⟹ AV regurgitation
DiGeorge Syn
乔治弟弟没胸没屁屁（无胸腺）, 没法乐死 （associated with TOF)
chr 22q11.2 deletion: thymic aplasia, failure of parathyroid formation from the defective 3rd and 4th pharyngeal pouches
hypocalcemic tetany, recurrent viral and fungal infections (no T cells); TOF!!!
Wegener’s disease
vs. Churg-Struass Syn
瓦格纳一看美女就流鼻血，其实是个肾衰的中性人
C-ANCAs, cytoplasmic-staining anti-neutrophil cytoplasmic Ab) cause granulomatosis with polyangiitis
Px: nectrotizing vasculitis of the upper and lower RI (nasal ulceration, sinusitis, hemoptysis) + rapidly progressive glomerulonephritis (produce RF)
斯特劳斯和瓦格纳对应（p-ANCA),
斯特劳斯有多动症（写了太多圆舞曲），神经质而且过敏
成人哮喘及过敏，嗜酸性粒细胞增多，多动脉炎，单、多神经炎，付鼻窦
Dx: wide, split S2?
characteristic for ASD
most important damage: pulmonary HT (can cause reversed R-L shunt: late onset cyanosis - Eisenmenger Syn)
Lambert-Eaton syn
autoimmune paraneoplastic syndrome, myasthenic symptoms, Ab against presynaptic Ca2+ channel can’t release Ach
often associated with small cell lung cancer
AFR (acute rheumatic fever)
Px: heart? CNS?
Dx criteria?
heart: days to 6 wks after “sore throat”: vegetation on MV, AV
CNS: Sydenham chorea, 2-3 mo after streptococcus infection
Dx requires 2 major Jones criteria + 2 minor Jones criteria:
- Major: carditis, polyarthritis, chorea, erythema marginatum, s.c. nodules
- minor: fever, arthralgia, ↑ ERS or C-reactive protein, prolonged PR interval
H produced by the posterior pituitary gland?
- vasopressin: increase permeability of the renal collecting ducts to water ⟹ ↑ water reabsorption
- oxytocin
mechanism for Adenosine, Ach to reduce HR?
pacemaker AP:
- phase 0 (upstroke): opening of L-type (long-lasting) Ca2+ channel
- phase 3 (repolarization): opening of K+ channel
- phase 4 (pacemaker potential): 慢Na+通道开放, K+ channel close: - 50 mV, then T (transient)-type Ca2+ channel open: - 40 mV, L-type Ca2+ channel open
Adenosine and Ach activates K+ channels and inhibit L-type Ca2+ channels
心脏听诊：
- apex murmur
- mid systolic click?
- S2-to-opening snap time interval: indicator of?
- audible S3: indicate? - murmur at right sternal border
- holosystolic murmur at left sternal border; attenuate with the handgrip
- fixed splitting of S2
- continuous precordial murmur, during both diastolic and systolic:
- systolic, crescendo-decrescendo murmur, start after S1 and end before the A2 component of S2
- MV
MR: holosystolic murmur at apex, radiate to axilla (腋窝）- presence of audible S3 is the indicator of severity
mid systolic click? MV prolapse
S2-to-opening snap time interval: indicator of MV stenosis severity
-audible S3: in young patient: indicate severity of MV regurgitaiton; in older patients: ↑ LVESV (occurs in the setting of LV systolic failure)
- AV
if “crescendo-decrescendo” systolic murmur: aortic regurgitation - holosystolic murmur at left sternal border: VSD
(handgrip ↑ Afterload) - fixed splitting of S2: ASD
5: PDA (patent ductus arteriosus) - AS (aortic stenosis)
职业性肺病的histologic表现：
1。 nodular interstitial densities, mostly in the apical region; calcified hilar ndes, (eggshell calcification) + bifrefringent particles
- lower lobes, involvement of pleural + pleural effusion ; ferruginous bodies (beaded rods with iron-containing coat)
1。 silicosis
- asbestosis
Dx:
African American, malaise, nocturnal fevers, cough + bilateral hilar adenopathy + biopsy shows non-caseating granulomas
sarcoidosis
if caseating granulomas: TB
