Biomedical subjects

W Huang

Publications and source records attributed to W Huang.

670 records · Page 38Linked to original sources

PubMedDate not supplied

Demonstration of megavoltage and diagnostic x-ray imaging with hydrogenated amorphous silicon arrays.

Flat-panel imagers consisting of the first large area, self-scanning, pixelated, solid-state arrays made with hydrogenated amorphous silicon (a-Si:H) are under development by the authors for applications in diagnostic x-ray and megavoltage radiotherapy imaging. The arrays, designated by the acronym MASDA for multi-element amorphous silicon detector array, consist of a two-dimensional array of a-Si:H photodiodes and thin-film transistors and are used in conjunction with scintillating materials. Imagers utilizing MASDA arrays offer a variety of advantages over existing technologies. This article presents initial megavoltage and diagnostic-quality x-ray images taken with several such arrays including the first examples of anatomical-phantom images. The external readout electronics and imaging techniques required to obtain such images are outlined, the construction, operation, and advantages of the arrays briefly reviewed, and the future potential of this new technology discussed.

Diagnostic Imaging↗

PubMedDate not supplied

Selenoprotein P in patients on home parenteral nutrition.

BACKGROUND: The purpose of this study was to evaluate the use of selenoprotein P as an indicator of selenium status in patients receiving home parenteral nutrition. METHODS: Adult patients (n = 38) who had been on parenteral nutrition with no addition of selenium for 3 to 216 months were included in the study. Plasma samples were analyzed for selenium, selenoprotein P, and extracellular glutathione peroxidase (eGSHPx) using fluorimetry and newly developed radioimmunoassays. RESULTS: The mean plasma (+/- SD) eGSHPx and selenoprotein P in the patients were 1.9 +/- 1.2 mg/L and 0.7 +/- 0.4 arbitrary units, respectively, which corresponds to about 50% of the concentration measured in the plasma of the reference subjects (4.0 +/- 1.0 mg/L and 1.50 +/- 0.17 arbitrary units). The mean plasma selenium concentration was 0.5 +/- 0.4 mumol/L, which was approximately half of the concentration measured in the healthy subjects (1.1 +/- 0.2 mumol/L). Thirty-four (89%) and 20 (53%) patients, respectively, had selenoprotein P and eGSHPx values lower than mean - 2 SD of the reference material. The lowest values observed for selenoprotein P and eGSHPx were 3% and 2% of the reference mean. Selenoprotein P levels correlated significantly to eGSHPx (p = 0.88, p < .0001) and plasma selenium (p = 0.91, p < .0001). CONCLUSIONS: The positive correlations between selenoprotein P and eGSHPX and plasma selenium indicates that selenoprotein P may be used as a marker of selenium status in selenium-depleted patients.

Aged↗

PubMedDate not supplied

Physiological knock-knee in preschool children: prevalence, correlating factors, gait analysis, and clinical significance.

Physiological knock-knee (PKK) was categorized by measuring intermalleolar distance (IMD), a clinically simple method, to evaluate the prevalence and correlating factors in 305 preschool children. The prevalence in this cross-sectional study was relatively high, and it was age related (p = 0.002; 64, 44, and 34% for ages 3-4, 4-5, and 5-6 years, respectively). The following factors were correlated with PKK: use of walking chair early (p = 0.0001), independently walked late (p = 0.0005), dependently walked longer (p = 0.0001), concurrence with flatfoot (p = 0.001), and angular deformity (toe in/out, p = 0.03). Gait analysis, with spatiotemporal, kinematics, and kinetics parameters, was performed to evaluate the ambulatory significance. Preschool children with PKK have a shorter stride length (p = 0.02) and a slower walking speed (p = 0.004). Dynamic hyperextension of the knee is noted for 8 degrees during the whole gait cycle (p < 0.05). We conclude that PKK is a variable that should be considered in the development of mature gait for preschool children.

Child↗

PubMedDate not supplied

The management of cardiovascular complications in elderly patients with coronary heart disease subjected to major surgical operations.

There was not a single cardiovascular mortality in 140 consecutive elderly patients with coronary heart disease who were subjected to major surgical operations. The age distribution, the varieties of coronary heart diseases, and surgical operations were listed. the preoperative preparation, management during and after the operations were presented. In the discussion (1), the well-coordinated teamwork among the physicians, surgeons, anesthetists, and nursing staff before, during, and after the operations was stressed. (2) The managements of various cardiovascular complications were discussed in detail. Illustrative case materials were presented whenever necessary.

Aged↗