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61.
Mark Ellis FRACO FRACS Ross Drewe MB BS DO † Justin O'Day FRACO FRACS 《Clinical & experimental ophthalmology》1994,22(2):119-123
Desmoplastic malignant melanoma (DMM) is a rare variant of spindle cell melanoma. We report a case of DMM of the forehead secondarily involving the orbit. The diagnosis was based on light microscopic features, including prominent peripheral cell nest formation and spindle cell fascicles in densely collagenous stroma. Immunohistochemical studies showed strong uniform staining for S100 antigen throughout the tumour. It was negative for HMB 45, smooth muscle actin, desmin, cytokeratins and Type IV collagen. Electron microscopy showed neither melanosomes nor myelin figures. The clinical and histological characteristics of desmoplastic malignant melanoma, and its differential diagnosis of malignant schwannoma, are discussed. DMM has a poor prognosis, since it tends to invade deeply, recur locally and metastasise readily. 相似文献
62.
Maryla Z Stelmach MB BS Justin O'Day FRACO FRACS † Hugh Ryan FRACO FRACS ‡ 《Clinical & experimental ophthalmology》1994,22(2):139-143
The history and clinical findings are presented of a patient who suffered from the uveal effusion syndrome over a 10-year period from 1956. The funduscopic appearance is illustrated both at the time of initial presentation and 36 years later. This condition typically affects healthy middle-aged men and causes recurrent, spontaneous, serous retinal and ciliochoroidal detachments, often resulting in significant visual impairment. Two separate hypotheses have been postulated to explain the pathogenesis of the uveal effusion syndrome, one relating to abnormally thickened sclera, the other to chronic bulbar hypotony. Both are discussed, as is the rationale behind the current management of this unusual condition. 相似文献
63.
Paul Fockens MD Carin G. Manshanden MD J.Jan B. van Lanschot MD Hugo Obertop MD Guido N.J. Tytgat MD 《Gastrointestinal endoscopy》1997,46(6):487-491
Background: Half of the patients who undergo surgery for cancer of the esophagus or gastric cardia present with recurrent disease within 2 years after the operation. We investigated the value of endosonography for the early detection of recurrent disease. Methods: Forty-three patients entered a follow-up protocol in which endosonography was performed every 6 months within the first 2 years after resection. Results: During 16 of a total of 66 examinations, suspicious abnormalities were found. In three patients free fluid was seen, but recurrence could not be confirmed during follow-up. In eight patients suspicious lymph nodes were seen; six died within 6 months, one was alive with a proven recurrence at 6 months, and one was alive without recurrence at 22 months. In five patients focal wall-thickening or a mass was seen; three died within 6 months, and two were alive with a proven recurrence at 2 and 5 months. After exclusion of free fluid, the positive predictive value of abnormalities on endoscopic ultrasonography (EUS) was 92%. Conclusions: Endosonography, performed at 6-month intervals after resection of cancer of the esophagus or gastric cardia, is accurate in the early detection of locoregional recurrent disease. Two thirds of the patients were still without symptoms when the recurrence was found. (Gastrointest Endosc 1997;46:487-91.) 相似文献
64.
Dawn Hastreiter MD PhD ; Jeannie Chao BS ; QI Wang MD ; Richard M. Ozuna MD ; Myron Spector PhD 《Wound repair and regeneration》2004,12(4):430-438
That a contractile actin isoform has been found in cells of other cartilage tissues in healing and disease states prompted this investigation of the presence of alpha-smooth muscle actin (alpha-SMA) in pathological human intervertebral disc tissue. The presence of this isoform has been reported in human intervertebral disc specimens obtained at autopsy from subjects for whom there were no reported symptoms. An objective of this study was to evaluate the cell density and percentage of alpha-SMA-containing cells in pathological nucleus pulposus tissue obtained from lumbar disc surgery from 17 patients. Additionally, explants of nucleus pulposus material were cultured to determine how alpha-SMA expression changed with time in vitro. Seventy-six 5-mm diameter explants (approximately 2 mm thick) pooled from six lumbar surgeries were cultured for 1, 2, 4, or 6 weeks. Microtomed sections of paraffin-embedded specimens were stained with hematoxylin and eosin or a monoclonal antibody to alpha-SMA. Histologically, cells were categorized as to alpha-SMA phenotype (positive or negative), and the areal cell density was determined. The evaluation of the cultured nucleus pulposus explants also included documentation of the percentage of cells that were round or elongated and the percentage of the cells that were part of a group (group: >/= 2 cells). Every nucleus pulposus section exhibited the presence of alpha-SMA-containing cells, which accounted for approximately 24 percent of the cells in vivo. In vivo, the cell density was significantly higher in older individuals (p = 0.02). The average time for cell outgrowth from the explants was 8.6 days. Approximately 10-15 percent of the cells in the explants stained positive for alpha-SMA. The time in culture had no significant effect on any of the outcome measures except the percentage of alpha-SMA-containing cells that were round (p = 0.008), with values decreasing through 4 weeks and then slightly rising at 6 weeks. The role of alpha-SMA in intervertebral disc pathology warrants further investigation. 相似文献
65.
Bruno Manzo Giuseppe Liistro Hugo De Clerck 《American journal of orthodontics and dentofacial orthopedics》2004,125(1):30-35
The purpose of this clinical trial was to evaluate the reliability and time saved with a plasma arc curing unit (Apollo 95E, Dental/Medical Diagnostic Systems, Woodland Hills, Calif) compared with a conventional curing unit (Ortholux XL 3000, 3M Unitek, St Paul, Minn) for direct bracket bonding with resin adhesive. Forty-five patients were involved in the study, and 608 brackets were bonded in a contralateral quadrant pattern. The patients were followed for a mean (+/- standard deviation) period of 11 +/- 3.2 months. Survival analysis was carried out to compare the failure rate for the 2 techniques. The time required for bonding with each technique was also recorded. The mean survival time was 399 days, and there were no significant differences in survival time between the 2 bonding methods. Twelve bonding failures were reported with each technique. The curing time per bracket was significantly reduced with the plasma curing light compared with a conventional curing unit (65 +/- 19 vs 82 +/- 31 seconds). The plasma arc curing light can save chair-time without affecting the bonding failure rate. 相似文献
66.
The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such a correlation can be made, then we propose that clinicians working with chronic pain patients may have improved outcomes if they address and correct faulty breathing patterns. Based on this study, it is suggested to include the evaluation and treatment of faulty respiration in the rehabilitation of chronic musculo-skeletal conditions, most notably cervical pain. 相似文献
67.
68.
69.
BACKGROUND: The efficacy of compression therapy depends mainly on the exerted pressure and on the stiffness of the material. OBJECTIVE: To propose a simple method by which pressure and stiffness can be assessed in the individual patient. MATERIAL AND METHODS: Using a pressure transducer (Kikuhime small probe, MediTrade, Soro, Denmark) the sub-bandage pressure is measured on the medial aspect of the lower leg at the transition of the gastrocnemius muscle into the Achilles' tendon. The pressure difference between active standing and lying is defined as the static stiffness index (SSI). Results: The accuracy and precision of the probe are good. Unna boot bandages (Lohmann-Rauscher, Vienna, Austria) and multilayer short-stretch bandages show a significantly higher SSI than long-stretch bandages and round-knitted class II stockings. The SSI values are lower than 10 mm Hg for elastic, long-stretch material and higher than 10 mm Hg for inelastic, short-stretch material. CONCLUSION: In future compression trials, pressure and stiffness measured in vivo should be declared. 相似文献
70.