C. K. Yen

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Portosystemic shunt fraction estimation using transcolonic iodine-123-iodoamphetamine (IMP) has been previously validated relative to portal vein macroaggregated albumin injections using an experimental model of cirrhosis. Transcolonic technetium-99m-pertechnetate (TcO4-) has been proposed as an alternative tracer to IMP to study portal circulation in(More)
Positron emission tomography of the brain with 75-sec rubidium-82 obtained from a portable generator (25-day Sr-82 leads to Rb-82) was used to evaluate the integrity of the blood-brain barrier (BBB) in patients with brain tumors. Rubidium is normally excluded from the central nervous system by the intact BBB, but when the BBB is disrupted by a tumor. Rb(More)
Dynamic positron tomography of the brain with 82 Rb, obtained from a portable generator [82Sr (25 days) - 82 Rb (76 sec)], provides a means of studying blood-brain barrier (BBB) permeability in physiological and clinical investigations. The BBB in rhesus monkeys was opened unilaterally be intracarotid infusion of 3 M urea. This osmotic barrier opening(More)
OBJECTIVE To assess whether infrared thermography can accurately predict the area of soft tissue necrosis that results from liquid nitrogen cryoprobe therapy. STUDY DESIGN Eight rats received cryosurgery on the shaved abdomen with a liquid nitrogen cryoprobe in a triple-freeze technique. The therapy was monitored with infrared thermography and(More)
With the use of an infrared thermographic camera; temperature patterns over the crowns of teeth were recorded. The temperature of upper incisor teeth decreased from gingival margin to incisal edge by approximately 2.5 degrees C. Vital and nonvital teeth were the same temperature at rest, but after cooling with cold air, nonvital teeth were slower to rewarm(More)
With the carbon dioxide surgical laser, the liquid nitrogen cryoprobe, and the scalpel, wounds were created on the shaved abdomen of 24 rats, and the patterns of healing were studied. The laser wounds were the first to epithelialize, followed by the scalpel wounds, with the cryosurgery wounds the slowest to epithelialize. The results were confirmed(More)
We present what we believe is the first reported case of a spontaneous aortoduodenal fistula, with massive rupture into the duodenum during the performance of a radionuclide study of gastrointestinal bleeding. Our experience suggests that nuclear scintigraphy with labeled red blood cells can help in the diagnosis of this disorder by demonstrating both the(More)
1. Because of their similarity in renal morphology and physiology to humans, domestic pigs (gilts, 70 kg) were bolus treated by intramuscular injection of 74, 17, and 6 mg kg-1 and by oral loading (70 mg kg-1 n = 4) of paraquat. The concentration peak of plasma paraquat was reached at 1.5 - 2.5 h. Renal clearance of paraquat rose to its maximum at 5-6 h(More)
The paper presents a new silicon wafer bonding technique. The high-resolution bonding pad is defined through pho-tolithography process. Photosensitive materials with patternable characteristics are served as the adhesive intermediate bonding layer between the silicon wafers. Several types of photosensitive materials such as SU-8 (negative photoresist),(More)