The process where nucleation and further precipitations occur by different components to form urinary stones, is called:
classical nucleation theory
heterogeneous nucleation
suspension solution
concentric lamination
Correct Answer :
B. heterogeneous nucleation
The process by which nuclei form in impure solutions is called heterogeneous nucleation. The nucleus and the overlying precipitants are, typically, of different matters.
Related Questions
What is the most appropriate antibiotic class for prophylaxis before urologic surgery?
aminoglycosides
macrolides
cephalosporins
fluoroquinolones
What is the favorable stone characteristic for ESWL treatment?
1000 - 1300 HU density
5 - 10 mm diameter
lower calyx location
mid ureteral location
What parameter impairs the kidney stone-free rate, after ESWL?
short skin-to-stone distance (SSD)
end-stage renal failure
a stone in the upper calyx
the presence of a 30 cm, 4.7 Fr ureteral stent in situ
When should renal stone patients be evaluated for metabolic diseases?
when stones are multiple and/or recurrent
when stones form in childhood
in cases where nephrocalcinosis and urolithiasis are present
all of the above
What is the incidence risk of ureteral strictures following ureteroscopy?
3 6 %
12 15 %
0.4 0.8 %
0.09 0.14 %
What medications do NOT cause renal stones?
ciprofloxacin
indinavir
thiazides
triamterene
What is the most favorable stone characteristics for laparoscopic and robotic approaches for the treatment of a kidney stone?
a stone in the lower calyx with a wide mouth of infundibulum and obtuse lower calyx to ureter angle
a stone in an anterior group calyceal diverticulum with thin overlying renal parenchyma
5 mm calcium-containing stone in an intrarenal pelvis and wide UPJ
6 years post anatrophic nephrolithotomy, recurrent mid calyceal stone
Which method of the following stone analysis techniques is based on the interaction of polarized light with the stone crystals?
wet chemical analysis
thermogravimetry
scanning electron microscopy
none of the above
What is the preferred drug for medical expulsive therapy for lower ureteral stones?
furosemide
tamsulosin
nifedipine
diclofenac
What is the most common organism that might complicate PCNL?
Proteus mirabilis
E. coli
Pseudomonas aeruginosa
Staphylococcus epidermidis
What is false concerning preputial stones?
form due to inspissated smegma
form due to stasis of urinary salts
cause inguinal lymphadenopathy
often associated with phimosis in uncircumcised males
What is the sure diagnostic finding of Ca.oxalate stones?
chemical analysis of a recovered stone
hypercalcemia
CT finding
high breakability on ESWL
What is the most favorable stone characteristic for PCNL treatment?
≥ 2 cm diameter
upper calyx location
Na.urate composition
600 - 800 HU density
What congenital anomaly is unlikely to result in stone formation?
left ureterocele
bifid right renal pelvis
neurogenic bladder
bilateral UPJ stenosis
What stones are radiopaque on plain X-ray film?
2,8 dihydroxyadenine stones
sulfa medications-induced stones
calcium oxalate stones
matrix stones
What is the proper sequence of the following stones when ordered from most radiopaque to most radiolucent as they appear on plain Xray film?
Ca.oxalate, Ca.phosphate, Na.urate, cystine
Ca.phosphate, Ca.oxalate, cystine, Na.urate
Ca.oxalate, Ca.phosphate, cystine, Na.urate
Ca.phosphate, Ca.oxalate, Na.urate, cystine
What is the preferred irrigation fluid during PCNL?
physiological saline 0.9%
glycine 1.5%
balanced salt solution
distilled water
Invasive intervention in stone patients is NOT indicated in the following condition:
stone size
unrelieved obstruction
infection and septicemia
recurrent stone formation
What could the discomfort experienced during ESWL session be related to?
the energy density of the shock waves as they pass through the skin
the size of the focal point
a & b
none of the above
What kind of stones is more likely to recur with infections if not removed completely?
urate
triple phosphate
oxalate monohydrate
matrix
What parameter is NOT considered in the stone burden concept?
the surface area of the stones
the volume of the stones
the density of the stones
the number of the stones
What type of stones is soft, resilient, composed of mucoproteins of urine and serum?
matrix
indinavir
brushite
2,8 dihydroxyadenine
For how long a completely obstructed ureter could be respited with no expected permanent damage to renal functions?
2 days
2 weeks
2 months
4 6 hrs.
What is false concerning urethral stones?
stones at posterior urethra could be pushed back to the bladder
stones at anterior urethra have to undergo a trial of milking out, using copious intra-urethral xylocaine gel
often respond to a two-week course of tamsulosin
respond to Holmium laser treatment
What is the least serious complications of PCNL?
uncontrollable bleeding
incomplete removal of stones
pneumothorax
colonic perforation
What is true concerning the use of intravenous fluids in renal colic cases?
patients should be given large amounts of fluids to hasten stones passage
fluids are given to keep the patient well hydrated
the recommended regimen is 2 L of ringer lactate over 2 hours
fluids are contraindicated if desmopressin (DDAVP) was given
What type of stones do laxative abusers might develop?
ammonium urate
sodium urate
calcium oxalate
calcium phosphate
Where do Randall plaques originate from?
transitional epithelium lining minor calyces
transitional epithelium lining major calyces
basement membrane of the loops of Henle
papillary tips of polar pyramids
What is the most common composition of ureteral stones?
Ca.phosphate
Ca.oxalate
Na.urate
struvite
Ureteral stones of ≥ 7 mm:
should be treated with more analgesics
must undergo metabolic worked out
are unlikely to pass out spontaneously
chemolysis should be tried first