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131.
We report on 9 patients with pilomatricomas that showed unusual histopathologic features. Our patients were mainly elderly individuals (age range 42 to 88 years; mean age 70.1 years) who presented solitary cutaneous nodules situated on the head and neck (7 neoplasms), upper arm (1 neoplasm), and back (1 neoplasm). All the lesions were treated by simple excision. Follow-up data available in 7 of the 9 patients (mean follow-up, 17 months) revealed local recurrences in 1 patient whose lesion recurred 3 times. No lymph node involvement or distant metastases were recorded in any of our cases. Histopathologically, most neoplasms were characterized by a relatively large lesion in the clermis that in some cases showed extension to the subcutis. Each lesion was predominantly composed of a lobular proliferation of basaloid cells in association with adjacent focal areas containing eosinophilic, cornified material with shadow cells. In some cases, relatively large areas of shadow cells were present, whereas, in others only small foci of shadows cells were observed. Cytomorphologically, the basaloid cells showed features of matrical and supramatrical cells of a normal hair follicle and exhibited variable nuclear atypia and mitotic figures. The overall architectural pattern of the neoplasms was different from that of large fully developed stereotypical pilomatricomas that maintain a cystic character with basaloid cells predominantly aligned at the periphery. Based on the histopathologic findings, namely the presence of a large, lobular proliferation of basaloid cells in association with small to large foci of shadow cells, we interpreted these neoplasms to be a distinctive proliferative variant of pilomatricoma and propose the designation "proliferating pilomatricoma." Proliferating pilomatricomas should be differentiated from the recently described matricoma, basal-cell carcinoma with matrical differentiation, and matrical carcinoma (pilomatrical carcinoma).  相似文献   
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PURPOSETo study the relationship of lumbar facet joint tropism to degeneration of the cartilage and subcortical bone in the facet joints and the effect of tropism in intervertebral disk degeneration.METHODSThe orientation of 104 cadaveric lumbar facet joints with respect to sagittal plane was measured on CT scans, and the joints were classified as having no tropism, mild tropism, or severe tropism. On MR images, the severity of cartilage degeneration and bony sclerosis was measured. The correlation between tropism and degeneration was calculated, as was the relationship among age, spinal level, and degeneration.RESULTSWe identified four spinal levels with severe tropism, six with moderate tropism, and 94 without tropism. Cartilage degeneration was not significantly more severe in the joints with tropism than in the joints without. Sclerosis was slightly greater in the joints with tropism than in the joints without it. Sclerosis and cartilage degeneration were significantly related to age and spinal level.CONCLUSIONAge, spinal level, and overall facet joint angle are more important factors in facet joint degeneration than is tropism.  相似文献   
137.
Tissue specimens from the large bowel of 18 patients with long-standing slow transit constipation were investigated to determine the distribution and density of several neuropeptides and amines in the enteric nerve system, and also of endocrine cells in comparison to normal individuals. CGRP (calcitonin gene-related peptide), galanin, glucagon, GRP (gastrin-releasing peptide), metenkephalin, motilin, neuropeptide Y (NPY), PACAP, peptide YY (PYY), serotonin, somatostatin, substance P and VIP were studied by immunohistochemistry. Tissue concentrations of VIP, substance P and galanin were also measured by radioimmunoassay. Significantly increased VIP, SP and galanin contents were found in specimens from the ascending colon. Levels of VIP and galanin were also increased in the transverse colon. Immunohistochemistry revealed only marginal changes with an increased density of PACAP nerve fibres in the smooth muscle and of VIP and PACAP nerves in the myenteric plexus of the transverse colon. In the descending colon substance P and NPY immunoreactivity were also increased in the myenteric plexus while the density of VIP nerve fibres was reduced in the mucosa/submucosa. The frequency of PYY-containing cells and the 5-HT-containing cells in the ascending colon was significantly increased in the constipated patients.  相似文献   
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OBJECTIVE: To describe Ontario emergency physicians' knowledge of colleagues' sexual involvement with patients and former patients, their own personal experience of such involvement, and their attitudes toward postvisit relationships. DESIGN: Mailed survey. SETTING: Ontario. PARTICIPANTS: Emergency physicians practising in Ontario. RESULTS: Of 974 eligible mailed surveys, 599 (61.5%) were returned. Of these respondents, 52 (8.7%) reported being aware of a colleague in emergency practice who had been sexually involved with a patient or former patient. When describing their own behaviour, 37 respondents (6.2%) reported sexual involvement with a former patient. However, of this group, only 9 (25.0%) had met the patient in an emergency department. Thus, of the total number of respondents, only 1.5% (9/599) reported sexual involvement arising out of an emergency department visit. Most respondents (82.4%) agreed that it is inappropriate behaviour to ask a patient for a date after an emergency assessment and before the patient's departure, and 66.4% felt that it is inappropriate to contact the patient after discharge. However, only 10.6% believed it to be unacceptable to request a social meeting after encountering a patient previously cared for in the emergency department in a nonprofessional setting. Most respondents (96.5%) did not believe that sexual involvement could ever be therapeutic for the patient. However, only 66% felt that it was always an abuse of power and 62.4% supported zero tolerance of all sexual involvement between physicians and patients. CONCLUSIONS: Vague regulatory guidelines currently in place have failed to dispel confusion regarding what is acceptable social behaviour for physicians providing emergency care. Our results support the need for clarification, and suggest a basis for guidelines that would be acceptable to the emergency medical community: that an emergency visit should not form the basis for the initiation of personal or sexual relationships, yet neither should it preclude their development in nonmedical settings.  相似文献   
139.
The effect of a newly developed patellar realignment brace was evaluated in 21 patellofemoral joints (19 patients) with patellar subluxation (13 joints with lateral subluxation and eight with medial subluxation) by using active-movement, loaded kinematic magnetic resonance (MR) imaging. Sixteen patellofemoral joints (76%) demonstrated a qualitative correction of or improvement in patellar subluxation (ie, centralization of the patella or a decrease in the displacement of the patella) after application of the brace. Four of the five “failures” occurred in patellofemoral joints that had patella alta and/or dysplastic bone anatomy. These results indicate that the patellar realignment brace was able to counteract patellar subluxation in the majority of patellofemoral joints studied, as shown by active-movement, loaded kinematic MR imaging. This brace appears to be useful for conservative treatment of patients with patellofemoral joint pain secondary to patellar malalignment and maltracking.  相似文献   
140.
Precise and limited decompression for lumbar spinal stenosis   总被引:3,自引:0,他引:3  
Summary Fifty-eight consecutive patients with lumbosacral nerve root entrapment due to spinal stenosis were treated with modified microsurgical decompression. Only the clinically relevant sides and levels were decompressed while the spinous processes, the interspinous ligaments, the medial portion of ligamentum flavum and the functionally important parts of the facet joints were preserved. The reviewers rated recovery as good or excellent in 71% of patients while patient self-assessment indicated 76% good or excellent outcome. These data suggest that microsurgical decompression of spondyloarthritic changes can effectively relieve the signs and symptoms of nerve root compression and that with careful evaluation of all available data the number of nerve roots requiring decomperession is often fewer than what is suggested by diagnositic images alone.  相似文献   
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