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1.
HOCK LEONG EE  MBBS  MRCP    CHEE LEOK GOH  MBBS  FRCP    KHOO    ES-Y. CHAN  PHD    POR ANG  MBBS  MRCP 《Dermatologic surgery》2006,32(1):34-40
BACKGROUND: Acquired bilateral nevus of Ota-like macules (Hori's nevus) is a common dyschromatosis among Asian women. Q-switched lasers have been used successfully as a treatment modality. OBJECTIVE: The purpose of this study was to compare the efficacy of using the Q-switched 532 nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser followed by the 1,064 nm laser versus the Q-switched 1,064 nm Nd:YAG laser alone in the treatment of Hori's nevus. METHODS: This is a prospective left-right comparative study. Ten women with bilateral Hori's nevus were recruited and treated with a combination of the Q-switched 532 and 1,064 nm Nd:YAG lasers on the right cheek and the Q-switched 1,064 nm Nd:YAG laser alone on the left cheek. Only one laser treatment session was performed. The degree of pigmentation was objectively recorded with a mexameter. Subjective assessment was made by both patients and two blinded, nontreating dermatologists. RESULTS: At 6 months, there was a statistically significant difference (p = .009) of 35.10 points using objective mexameter measurements between the two sides, favoring the side treated with a combination of 532 and 1,064 nm laser treatment. Subjective grading by the patients and blinded dermatologists also confirmed that combination therapy was more successful after one treatment. Although combination treatment had a higher incidence of mild postinflammatory changes, this disappeared within 2 months. CONCLUSIONS: Concurrent use of the Q-switched 532 nm Nd:YAG laser in combination with the 1,064 nm laser is more effective in pigment clearance than the Q-switched 1,064 nm Nd:YAG laser alone for Hori's nevi.  相似文献   
2.
Apoptotic cells, e.g. postinflammatory neutrophils, were reported to be engulfed by phagocytes without induction of an inflammatory response. We investigated the humoral immune response of BALB/c mice after repeated injection of viable or apoptotic human T cells. Following interleukin-2 (IL-2) deprivation, phytohaemagglutinin (PHA)/IL-2 expanded human T-cell lines were irradiated with UV-B light to induce apoptosis, confirmed by propidium iodide staining of Triton X-100-lysed cells. Indirect immunofluorescence was used to detect antilymphocyte antibodies 7 days after each injection. We found high levels of antilymphocyte antibodies in all animals immunized with viable T cells, whereas animals injected with apoptotic cells showed a significantly reduced humoral immune response. We conclude that apoptotic cells induce poor xenoreactive T-cell responses when compared with viable cells.  相似文献   
3.
Kim  EE; Pjura  G; Lowry  P; Verani  R; Sandler  C; Flechner  S; Kahan  B 《Radiology》1986,159(2):443-446
Serial radionuclide studies using both Tc-99m DTPA (perfusion) and I-131 hippuran (tubular function) were correlated with histologic findings in 25 patients with renal transplants. These cases included 15 cases of cyclosporin-A nephrotoxicity (CsA-NT) and ten cases of acute cellular rejection that were retrospectively selected on the basis of biopsy findings and favorable clinical response to therapy specific for each of these conditions. The serial radionuclide studies enabled the correct diagnosis in 12 of 15 cases of CsA-NT and eight of ten cases of acute rejection. Posttherapy radionuclide studies, furthermore, demonstrated improvement consistent with clinical response. In all cases, the radionuclide results were available at least 24 hours before biopsy findings. These results indicate that serial radionuclide studies evaluating interval changes in both perfusion and tubular function are of significant value in the diagnosis and follow-up of CsA-NT and acute cellular rejection in transplant recipients. This initial experience suggests a sensitivity of 80%.  相似文献   
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基于物体空间序法的CT图像三维重建算法的研究   总被引:5,自引:0,他引:5  
首先对三维可视化方法进行了分类概述。接着对基本的物体空间序法及其改进算法——抛雪球法做了详细的描述,并且通过对两组CT数据进行三维重建实验,得到高质量的重构图像。最后,本文研究并采用了提取表面体素进行体绘制加速的方法,实现了基于等值面提取表面的加速算法,实验证明加速算法能够满足显示要求并能起到明显的加速作用。  相似文献   
8.
Summary Urinary and fecal total, isomer I, and isomer III coproporphyrin excretion of a Rotor's syndrome patient and his family were determined. The proprositus showed increased urinary total coproporphyrin excretion (248 µg/24 h) and a shift of the coproporphyrin isomer I/III relation (70%/30%). The propositus's father and two siblings also had elevated renal excretion of coproporphyrin I. Total coproporphyrin excretion was enhanced only in the propositus's father and one sibling, while being normal in another sibling. All family members that could be investigated showed considerably decreased fecal porphyrin excretion. In Rotor's syndrome porphyrin excretion is mainly renal. The coproporphyrin isomer I/III relation is shifted towards isomer I. Phenotypically normal relatives with normal bilirubin plasma levels may have alterations in both their renal and enteral coproporphyrin excretion.
Herrn Professor Dr. med. N. Zöllner zum 65. Geburtstag gewidmet  相似文献   
9.
A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD) locus of the X chromosome has duplicated to specific locations near the pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11. Comparative sequence analysis reveals 92-96% nucleotide identity, indicating that the autosomal ALD paralogs arose relatively recently during the course of higher primate evolution (5-10 million years ago). Analysis of sequences flanking the duplication region identifies the presence of an unusual GCTTTTTGC repeat which may be a sequence-specific integration site for the process of pericentromeric- directed transposition. The breakpoint sequence and phylogenetic analysis predict a two-step transposition model, in which a duplication from Xq28 to pericentromeric 2p11 occurred once, followed by a rapid distribution of a larger duplicon cassette among the pericentromeric regions. In addition to facilitating more effective mutation detection among ALD patients, these findings provide further insight into the molecular basis underlying a pericentromeric-directed mechanism for non- homologous interchromosomal exchange.   相似文献   
10.
Fujita  H; Doi  K; Chan  HP; Giger  ML; Duda  EE 《Radiology》1985,155(3):799-803
Two types of phantoms were developed with which to evaluate the overall performance of digital subtraction angiography (DSA) systems. A dynamic phantom, called a "fish bone" phantom, consists of polyethylene tubes that simulate blood vessels with various lesions, such as stenoses, ulcers, and aneurysms. With this phantom, washout curves were obtained representing the relationship between iodine content and time. It will be useful for qualitative assessment of DSA images, evaluation of different image-processing schemes, and studies of blood flow analysis. A static phantom, called a "C-D" phantom, can be used for measurement of quantitative contrast-detail (C-D) diagrams and for daily monitoring of DSA systems. This was constructed of tubes of seven different diameters (2.15-0.28 mm) and 14 different concentrations of contrast medium (100%-1.1% Renografin-76 [meglumine and sodium diatrizoate]). The C-D diagrams were determined from an observer performance study using C-D phantom images obtained at four different DSA settings.  相似文献   
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