Biomedical subjects

Hongzhi Zhang

Publications and source records attributed to Hongzhi Zhang.

3 recordsLinked to original sources

PubMed2005

Computerized diagnosis from tongue appearance using quantitative feature classification.

This study investigates relationships between diseases and the appearance of the human tongue in terms of quantitative features. The experimental samples are digital tongue images captured from three groups of candidates: one group in normal health, one suffering with appendicitis, and a third suffering with pancreatitis. For the purposes of diagnostic classification, we first extract chromatic and textural measurements from original tongue images. A feature selection procedure then identifies the measures most relevant to the classifications, based on which of the three tongue image categories are clearly separated. This study validates the use of tongue inspection by means of quantitative feature classification in medical diagnosis.

Appendicitis↗

PubMed2004

Protective effect of estrogen on intestinal ischemia-reperfusion injury in pubertal rats.

PURPOSE: This study investigated the role of 17beta-estradiol (E(2)) in intestinal ischemia-reperfusion (I/R) injury and its possible mechanism. METHODS: Rats of pubertal age were ovariectomized and injected subcutaneously with vehicle (vehicle group) or E(2) (100 or 500 mug/kg/every other day, E(2) or 5E(2) group) for 4 weeks. Other rats of the same age underwent sham ovariectomy as a control group. The rats in each group (n = 15) were subjected to superior mesenteric artery occlusion followed by 1 hour (n = 5), 6 hours (n = 5), or 24 hours (n = 5) reperfusion. Intestine specimens then were obtained for the determination of histopathologic score, inducible nitric oxide synthase (iNOS) mRNA expression, and iNOS activity. RESULTS: In vehicle, control, E(2), and 5E(2) groups, the histopathologic scores were 3.31 +/- 0.12, 3.00 +/- 0.09, 2.57 +/- 0.12, and 2.98 +/- 0.08, respectively. The expression levels of iNOS mRNA were 3.85 +/- 0.42, 4.86 +/- 0.76, 5.17 +/- 0.34, and 4.25 +/- 0.41 log copies, respectively. Lower histopathologic score but higher iNOS mRNA expression were found in E(2) group than in the other groups (P < .01). The level of iNOS activity paralleled the expression of iNOS mRNA. CONCLUSIONS: Estrogen may exert a protective effect on intestinal I/R injury in pubertal rats, probably by enhancing iNOS expression.

Aging↗

PubMed2002

[PIV: a computer-aided portal image verification system].

Portal image verification (PIV) is one of the key actions in QA procedure for sophisticated accurate radiotherapy. The purpose of this study was to develop a PIV software as a tool for improving the accuracy and visualization of portal field verification and computing field placement errors. PIV was developed in the visual C++ integrated environment under Windows 95 operating system. It can improve visualization by providing tools for image processing and multimode images display. Semi-automatic register methods make verification more accurate than view-box method. It can provide useful quantitative errors for regular fields. PIV is flexible and accurate. It is an effective tool for portal field verification.

Algorithms↗