YPO4 phosphors single-doped with Sb3+ or Gd3+ and co-doped with Sb3+ and Gd3+were prepared by a solid-state reaction method. The phase purity, morphology, photoluminescence excitation and emission properties of the pr...YPO4 phosphors single-doped with Sb3+ or Gd3+ and co-doped with Sb3+ and Gd3+were prepared by a solid-state reaction method. The phase purity, morphology, photoluminescence excitation and emission properties of the prepared phosphors were inves-tigated. The results showed that Sb3+ could sensitize Gd3+ in the co-doped phosphors which made the phosphors excitable by short-wave ultraviolet (UV) at a wavelength between 220 and 260 nm. Under 253.7 nm excitation, the co-doped phosphors Y1–x–yPO4: Sb3+x,Gd3+yshowed strong emission of Gd3+ at a wavelength of 312 nm whose intensity changed with the doping concentrations of Gd3+ and Sb3+. The optimized Y0.77PO4:Sb3+0.07,Gd3+0.16 phosphor showed an intensity comparable to commercial LaPO4:Ce phosphor (UVB-315), making it a potential candidate for mercury low-pressure discharge narrow-band UV-B emitting lamps.展开更多
AIM: To examine the efficacy of non-magnifying narrow-band imaging(NM-NBI) imaging for small signet ring cell carcinoma(SRC).METHODS: We retrospectively analyzed 14 consecutive small intramucosal SRCs that had been tr...AIM: To examine the efficacy of non-magnifying narrow-band imaging(NM-NBI) imaging for small signet ring cell carcinoma(SRC).METHODS: We retrospectively analyzed 14 consecutive small intramucosal SRCs that had been treated with endoscopic submucosal dissection(ESD) and 14 randomly selected whitish gastric ulcer scars(control). The strength and shape of the SRCs and whitish scars by NM-NBI and white-light imaging(WLI) were assessed with Image J(NIH, Bethesda).RESULTS: NM-NBI findings of SRC showed a clearly isolated whitish area amid the brown color of the surrounding normal mucosa. The NBI index, which indicates the potency of NBI for visualizing SRC, was significantly higher than the WLI index(P = 0.001), indicating SRC was more clearly identified by NM-NBI. Although the NBI index was not significantly different between SRCs and controls, the circle(C)-index, as an index of circularity of tumor shape, was significantly higher in SRCs(P = 0.001). According to the receiveroperating characteristic analysis, the resulting cut-off value of the circularity index(C-index) for SRC was 0.60(85.7% sensitivity, 85.7% specificity). Thus a lesion with a C-index ≥ 0.6 was significantly more likely to be an SRC than a gastric ulcer scar(OR = 36.0; 95%CI: 4.33-299.09; P = 0.0009).CONCLUSION: Small isolated whitish round area by NM-NBI endoscopy is a useful finding of SRCs which is the indication for ESD.展开更多
Vitiligo is a common, acquired pigmentary disorder of unknown etiology with great impact on patient's appearance and quality of life. It presents a therapeutic challenge to many dermatologists. Photochemotherapy u...Vitiligo is a common, acquired pigmentary disorder of unknown etiology with great impact on patient's appearance and quality of life. It presents a therapeutic challenge to many dermatologists. Photochemotherapy using psoralen and ultraviolet A(UVA) therapy, topical and oral immunosuppresants, as well as cosmetic camouflage are also commonly employed with varying clinical efficacy. Phototherapy is a popular treatment option, which includes both of the generalized ultraviolet B(UVB) therapies, broadband UVB and narrowband UVB(NB-UVB). It has been used favorably, both alone as well as in combination with other agents like topical calcineurin inhibitors, vitamin-D analogs. Combination therapies are useful and may provide quicker regimentation and treat vitiligo with an additive mechanism of action than UVB phototherapy. Advances in technology may lead to the continuing use of UVB phototherapy as a treatment for vitiligo through the development of sophisticated devices and delivery systems as well as innovative application methods. These will provide increased therapeutic options for all vitiligo patients, particularly those with refractory disease. In this article, I have reviewed the available data pertaining to efficacy and safety issues for NB-UVB as monotherapy, its comparison with psoralen plus UVA and other modes of phototherapy, combination regimens that have been tried and future prospects of NB-UVB in vitiligo.展开更多
文摘YPO4 phosphors single-doped with Sb3+ or Gd3+ and co-doped with Sb3+ and Gd3+were prepared by a solid-state reaction method. The phase purity, morphology, photoluminescence excitation and emission properties of the prepared phosphors were inves-tigated. The results showed that Sb3+ could sensitize Gd3+ in the co-doped phosphors which made the phosphors excitable by short-wave ultraviolet (UV) at a wavelength between 220 and 260 nm. Under 253.7 nm excitation, the co-doped phosphors Y1–x–yPO4: Sb3+x,Gd3+yshowed strong emission of Gd3+ at a wavelength of 312 nm whose intensity changed with the doping concentrations of Gd3+ and Sb3+. The optimized Y0.77PO4:Sb3+0.07,Gd3+0.16 phosphor showed an intensity comparable to commercial LaPO4:Ce phosphor (UVB-315), making it a potential candidate for mercury low-pressure discharge narrow-band UV-B emitting lamps.
文摘AIM: To examine the efficacy of non-magnifying narrow-band imaging(NM-NBI) imaging for small signet ring cell carcinoma(SRC).METHODS: We retrospectively analyzed 14 consecutive small intramucosal SRCs that had been treated with endoscopic submucosal dissection(ESD) and 14 randomly selected whitish gastric ulcer scars(control). The strength and shape of the SRCs and whitish scars by NM-NBI and white-light imaging(WLI) were assessed with Image J(NIH, Bethesda).RESULTS: NM-NBI findings of SRC showed a clearly isolated whitish area amid the brown color of the surrounding normal mucosa. The NBI index, which indicates the potency of NBI for visualizing SRC, was significantly higher than the WLI index(P = 0.001), indicating SRC was more clearly identified by NM-NBI. Although the NBI index was not significantly different between SRCs and controls, the circle(C)-index, as an index of circularity of tumor shape, was significantly higher in SRCs(P = 0.001). According to the receiveroperating characteristic analysis, the resulting cut-off value of the circularity index(C-index) for SRC was 0.60(85.7% sensitivity, 85.7% specificity). Thus a lesion with a C-index ≥ 0.6 was significantly more likely to be an SRC than a gastric ulcer scar(OR = 36.0; 95%CI: 4.33-299.09; P = 0.0009).CONCLUSION: Small isolated whitish round area by NM-NBI endoscopy is a useful finding of SRCs which is the indication for ESD.
文摘Vitiligo is a common, acquired pigmentary disorder of unknown etiology with great impact on patient's appearance and quality of life. It presents a therapeutic challenge to many dermatologists. Photochemotherapy using psoralen and ultraviolet A(UVA) therapy, topical and oral immunosuppresants, as well as cosmetic camouflage are also commonly employed with varying clinical efficacy. Phototherapy is a popular treatment option, which includes both of the generalized ultraviolet B(UVB) therapies, broadband UVB and narrowband UVB(NB-UVB). It has been used favorably, both alone as well as in combination with other agents like topical calcineurin inhibitors, vitamin-D analogs. Combination therapies are useful and may provide quicker regimentation and treat vitiligo with an additive mechanism of action than UVB phototherapy. Advances in technology may lead to the continuing use of UVB phototherapy as a treatment for vitiligo through the development of sophisticated devices and delivery systems as well as innovative application methods. These will provide increased therapeutic options for all vitiligo patients, particularly those with refractory disease. In this article, I have reviewed the available data pertaining to efficacy and safety issues for NB-UVB as monotherapy, its comparison with psoralen plus UVA and other modes of phototherapy, combination regimens that have been tried and future prospects of NB-UVB in vitiligo.