The illuminance characteristics of LED (Lighting Emitting Diode) Surgical Luminaire is researched in this paper from the aspects of the LED Single-tube illumination analysis, LED arrays distribution and lighting design. The facula distribution characteristics of the LED prototype and multi-facet entirety reflection Surgical Luminaire is tested and compared according to the standards. The results of experimental show that LED prototype can fully meet the surgical illumination requirements, and the LED's own characteristics and further development will greatly broaden the space of medical lighting.
Equipment Design ; Light ; Lighting ; instrumentation ; Surgical Equipment

To investigate the Fe2+ effects on root tips in rice plant, experiments were carried out using border cells in vitro. The border cells were pre-planted in aeroponic culture and detached from root tips. Most border cells have a long elliptical shape. The number and the viability of border cells in situ reached the maxima of 1600 and 97.5%, respectively, at 20-25 mm root length. This mortality was more pronounced at the first 1-12 h exposure to 250 mg/L Fe2+ than at the last 12-36 h. After 36 h, the cell viability exposed to 250 mg/L Fe2+ decreased to nought, whereas it was 46.5% at 0 mg/L Fe2+. Increased Fe2+ dosage stimulated the death of detached border cells from rice cultivars. After 4 h Fe2+ treatment, the cell viabilities were > or =80% at 0 and 50 mg/L Fe2+ treatment and were <62% at 150, 250 and 350 mg/L Fe2+ treatment; The viability of border cells decreased by 10% when the Fe2+ concentration increased by 100 mg/L. After 24 h Fe2+ treatment, the viabilities of border cells at all the Fe2+ levels were <65%; The viability of border cells decreased by 20% when the Fe2+ concentration increased by 100 mg/L. The decreased viabilities of border cells indicated that Fe2+ dosage and treatment time would cause deadly effect on the border cells. The increased cell death could protect the root tips from toxic harm. Therefore, it may protect root from the damage caused by harmful iron toxicity.
Iron ; toxicity ; Oryza ; cytology ; drug effects ; growth & development ; Plant Roots ; cytology ; drug effects ; growth & development ; Seedlings ; cytology ; drug effects ; growth & development

Objective To evaluate the role of late course accelerated fractions.ted irradiation(LCAF) combined with concurrent chemotherapy in the management of esophageal carcinoma.Methods From March 1998 to July 2000,111 eligible patients were randomized into LCAF alone group(LCAF,57 patients)or LCAF plus concurrent chemotherapy group(LACF-CT,54 patients).The radiotherapy regimen was identical in the two groups,consisting of conventional fractionation in the first 2/3 course and accelerated fractionation in the second 1/ 3 course to a total dose of 68.4 Gy/41 Fx/44 d.Chemotherapy regimen consisted of four eycles of cisplatin 25 mg/ (m~2?d)plus fluorouracil 600 mg/(m~2?d)on day 1 to 3 every 4 weeks and was delivered on the first day of radiotherapy.Results The median follow-up time was 67.1 months(range 47.6-76.4 months).The 1-,3-,5- year survival rate was 67%,44% ,40% and 77%,39% 28% in LACF-CF and LEAF group,respectively(P =0.310).Grade 3+4 acute side-effact was 42% and 25% in LCAF-CT and LCAF group,respectively(P＜0. 05),with 3 treatment-related deaths in the LCAF-CT group.Conclusions Late course accelerated fractionated irradiation combined with concurrent chemotherapy has a trend towards improving the survival,at the cost of increasing acute side-effect.Its role needs further confirmation by larger sample studied in randomization.