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71.
PURPOSE: To investigate the effect of exhaust particles on orbital blood flow velocity of the ophthalmic artery, central retinal artery, and posterior ciliary artery by color Doppler ultrasonography in highway toll collectors. MATERIAL AND METHODS: Color Doppler imaging was used to measure the peak-systolic and end-diastolic flow velocities and resistivity indices of the ophthalmic artery, central retinal artery, and posterior ciliary artery in 20 toll collectors and 20 controls. RESULTS: Both the peak-systolic and the end-diastolic flow velocities were decreased in the ophthalmic artery, central retinal artery, and posterior ciliary artery, and the resistivity index was increased in the central retinal artery in toll collectors when compared with control groups. Results were considered statistically significant if P<0.05. CONCLUSION: It was determined that the effect of exhaust particles reduced ocular blood flow velocity in toll collectors as measured by color duplex Doppler ultrasonography.  相似文献   
72.
OBJECTIVE: To determine the relationship between thyroid blood flow and anthropometric measurements, pubertal stage, and thyroid and gonadotropic hormones. MATERIALS AND METHODS: We examined 123 healthy school-aged children prospectively (69 boys (56.1%) and 54 girls (43.9%), 7-17 years old). Their sex, age, body weight, height, body mass index (BMI), and pubertal stage were determined. Serum thyrotropin, free thyroxine, luteinizing hormone, and follicle stimulating hormone were measured in both genders, along with testosterone in boys and estradiol in girls. The peak systolic velocity (PSV), resistance index (RI), and pulsatility index (PI) of the superior thyroid artery were determined. The correlations between the Doppler parameters and these factors were investigated. RESULTS: There were no differences in age, weight, height, BMI, thyroid volume, PSV, RI, or PI between boys and girls (P>0.05). The PSV and PI showed strong correlations with age, height, weight, puberty stage, thyroid volume, and BMI. The RI showed a strong inverse correlation with age, height, weight, puberty stage, and thyroid volume and a weak inverse correlation with the BMI. CONCLUSION: Determination of the thyroid arterial flow in normal healthy children is important during a Doppler ultrasound (US) examination. Doppler US parameters and their percentiles should be described in healthy children from different age groups, and these percentiles will aid in interpreting Doppler US in children.  相似文献   
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Background

Angiomyxoma is a benign proliferative mesenchymal tumor and a very rare mass in the larynx. There is not enough information about the etiology, clinical finding, treatment and prognosis of laryngeal angiomyxoma.

Case Details

A 52 years old man presented with respiratory distress. Also, he had suffered from dysphagia, dysphonia, cough, and obstructive sleep apnea in the supine position for 6 months. He was operated on via transoral approach under general anesthesia with orotracheal intubation. The mass was encapsulated and completely removed. The histopathologic diagnosis was reported as angiomyxoma.

Conclusion

Angiomyxoma should be considered in the differential diagnosis of the larynx masses. The treatment of angiomyxomas of the larynx is surgical. The mass can be usually excised intraorally or endoscopically.  相似文献   
75.
Venous ulcers are characterised by longstanding and recurrent loss of skin integrity. Once occurred, healing is slow and recurrence is high because of inappropriate conditions of the wound bed. This study involves 20 patients with chronic venous ulcers at least 6 weeks of duration treated with negative pressure wound therapy (NPWT). Patients underwent a radical debridement of all devitalised tissues in the first operation. After adequate haemostasis, silver-impregnated polyurethane foam was applied. Once the wounds were determined to be clean and adequate granulation tissue formation was achieved, split-thickness skin grafts were applied. Black polyurethane foam was applied over them. All wounds completely healed without the need for further debridement or regrafting. The mean number of silver-impregnated foam dressing changes prior to grafting was 2·9 (one to eight changes). The mean number of NPWT foam changes was 2·6 after skin grafting (two to five changes). Two patients who did not use conservative treatments for chronic venous insufficiency (CVI) after discharge from the hospital had recurrence of venous ulcers in the follow-up period. Application of NPWT provides quick wound-bed preparation and complete graft take in venous ulcer treatment.  相似文献   
76.
This paper proposes a divide-and-conquer strategy for designing brain machine interfaces. A nonlinear combination of competitively trained local linear models (experts) is used to identify the mapping from neuronal activity in cortical areas associated with arm movement to the hand position of a primate. The proposed architecture and the training algorithm are described in detail and numerical performance comparisons with alternative linear and nonlinear modeling approaches, including time-delay neural networks and recursive multilayer perceptrons, are presented. This new strategy allows training the local linear models using normalized LMS and using a relatively smaller nonlinear network to efficiently combine the predictions of the linear experts. This leads to savings in computational requirements, while the performance is still similar to a large fully nonlinear network.  相似文献   
77.
Several measurement techniques have been developed to address the capability for target volume reduction via target localization in image-guided radiotherapy; among these have been ultrasound (US) and fiducial marker (FM) software-assisted localization. In order to assess interchangeability between methods, US and FM localization were compared using established techniques for determination of agreement between measurement methods when a 'gold-standard' comparator does not exist, after performing both techniques daily on a sequential series of patients. At least 3 days prior to CT simulation, four gold seeds were placed within the prostate. FM software-assisted localization utilized the ExacTrac X-Ray 6D (BrainLab AG, Germany) kVp x-ray image acquisition system to determine prostate position; US prostate targeting was performed on each patient using the SonArray (Varian, Palo Alto, CA). Patients were aligned daily using laser alignment of skin marks. Directional shifts were then calculated by each respective system in the X, Y and Z dimensions before each daily treatment fraction, previous to any treatment or couch adjustment, as well as a composite vector of displacement. Directional shift agreement in each axis was compared using Altman-Bland limits of agreement, Lin's concordance coefficient with Partik's grading schema, and Deming orthogonal bias-weighted correlation methodology. 1,019 software-assisted shifts were suggested by US and FM in 39 patients. The 95% limits of agreement in X, Y and Z axes were +/-9.4 mm, +/-11.3 mm and +/-13.4, respectively. Three-dimensionally, measurements agreed within 13.4 mm in 95% of all paired measures. In all axes, concordance was graded as 'poor' or 'unacceptable'. Deming regression detected proportional bias in both directional axes and three-dimensional vectors. Our data suggest substantial differences between US and FM image-guided measures and subsequent suggested directional shifts. Analysis reveals that the vast majority of all individual US and FM directional measures may be expected to agree with each other within a range of 1-1.5 cm. Since neither system represents a gold standard, clinical judgment must dictate whether such a difference is of import. As IMRT protocols seek dose escalation and PTV reduction predicated on US- and FM-guided imaging, future studies are needed to address these potential clinically relevant issues regarding the interchangeability and accuracy of novel positional verification techniques. Comparison series with multiple image-guidance systems are needed to refine comparisons between targeting methods. However, we do not advocate interchangeability of US and FM localization methods.  相似文献   
78.
The medial canthus represents a fixed-point fulcrum that is necessary for eyelid function. The aim of the study was to investigate the arterial distribution of the inner canthus. The origin, calibration, and branches of the inner canthus arteries and their topographical relations were examined by dissecting 19 cadavers, injecting red latex to their corresponding 38 nasal sections before the dissection. The distance from the dorsal nasal artery to the inner canthus was found to be 7.2 +/- 0.3 mm. In this study, the average diameter of the dorsal nasal artery was 0.74 mm on the right side and 0.88 mm on the left. Concerning the course of dorsal nasal artery on the lateral side of the nose, 4 types were observed. In most of the examples (44.7%), dorsal nasal artery anastomosed with angular artery via thick branch and gave off supplying branches to the medial canthus and to the lateral side of the nose. Dorsal nasal artery is a vessel of satisfactory size and is potentially a good vascular source for a thin free flap. It may be an ideal flap to reconstruct the eyelid defect for texture and color similarity of the inner canthus skin. A better understanding of the inner canthus vascularity should allow modification of reconstructive techniques and reduce postoperative complications.  相似文献   
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Anterior sacral meningocele is a rare condition characterized by the herniation of meningeal membranes and cerebrospinal fluid through a defect in the anterior aspect of the sacrum. We report a case of an anterior sacral meningocele that was mimicking an ovarian cyst.  相似文献   
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