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排序方式: 共有528条查询结果,搜索用时 15 毫秒
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   
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Following an analysis of current treatment strategies for spontaneous pneumothorax and their surrounding controversies, the paper reports the Authors' personal experience. From 1 January 1984 to 31 December 1989 a total of 76 cases of spontaneous pneumothorax were treated, of which 3 were bilateral. The M:F ratio was 9:1 and the age of patients ranged between 16 and 77 years (mean age 39.2); 22 cases were relapses (27.8%). Conservative therapy was used in 12 cases (15.1%); pleural drainage was introduced in 54 cases (68.3%) for a mean of 7.5 days. Fourteen thoracotomies were performed in 13 patients (10.4%): bullectomy was performed 10 times with stapler, whereas pleurodesis was obtained in 9 cases using pleural abrasion and in 5 cases using apical pleurectomy plus pleural abrasion. Axillary thoracotomy at the 5th space was most commonly used. No major complications were observed during the postoperative period and, in spite of the minimum follow-up of 3 months, no cases of relapse were observed in operated patients.  相似文献   
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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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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   
6.
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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BACKGROUND: Saphenous vein remains an elective conduit for up to 85% of coronary bypass operations. It is obtained through one or numerous skin incisions, with a reported morbidity varying from 5% to 25%. The endoscopic vein harvesting (EVH) technique was developed to minimize this morbidity and to improve clinical outcomes. The aim of this study was to review the feasibility of this method, its learning curve, and changing results in a group without previous experience in this procedure. METHODS: Between July 1998 and October 1999, 179 patients for coronary artery bypass grafting underwent EVH (Vasoview Guidant, USA "double access" and Uniport), by two operators. Results were reported based on time of harvesting, length of conduits, technical details, and clinical outcomes, and divided into six groups of 30 consecutive patients each. RESULTS: Patient demographics were as follows: 86.03% were male, aged 64.3+/-9.12 years (range, 43 to 92 years), with diabetes mellitus in 28.49%, obesity in 18.43%, and vascular disease in 11.17%. The EVH method was limited to the thigh in 77.65% of cases and extended to the leg in 22.35%. Patients received an average of 2.45+/-0.58 incisions and obtained conduits had a mean length of 34.96+/-9.65 cm (range, 15 to 70 cm). The number of venous bypasses per patient was 1.30+/-0.59. Mean time of EVH was 47.24+/-19.84 minutes (range, 15 to 120), with a length-time index of 0.85+/-0.36. Primary success was achieved in 95.54%, with crossover to open technique in 4.46%. General morbidity was 8.9%, with hematoma in 1.11%, skin necrosis in 1.11%, infection in 6.7%, and readmission in 1.11%. CONCLUSIONS: Endoscopic vein harvesting is a feasible and reproducible method, with a typical learning curve, acceptable morbidity, and unquestionable benefits for coronary artery bypass graft patients.  相似文献   
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