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51.
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   
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Thirty-two castrated male crossbred growing pigs (average initial wt 26.9 kg) were used to determine the effect of a high level of dietary protein (37%) compared with a normal level of protein (15%) on enterobacteria and Campylobacter sp. inhabitation in the large intestine and on visceral organ hypertrophy and the interrelationships between these two factors. Pigs were kept in pairs (eight pens of two pigs/diet) and fed their respective diets and libitum. Eight pigs (two pens of two pigs fed each diet) were killed at wk 4, 8, 12 and 16 without fasting. Fecal samples were obtained every 2 wk from animals scheduled for necropsy at 16 wk, and colon contents were obtained from all pigs at necropsy; samples were enumerated individually for enterobacteria and Campylobacter sp. Weights of heart, lungs, liver, kidneys, perirenal fat and empty stomach, small intestine and large intestine were recorded at necropsy. Stomach, cecum and proximal colon were sectioned for histopathologic examination. Daily body weight gain was depressed by high dietary protein, but liver and kidneys were heavier in the high protein group than in controls at each time interval. Mild lymphoid hyperplasia of Peyer's patches in the small intestine in some pigs in both groups was indicative of antigenic stimulation but not of pathologic significance. There was no effect of diet on counts of enterobacteria or Campylobacter sp. in feces or colon contents during the 16-wk experiment. We conclude that the hypertrophic response of the tissues of growing pigs to high dietary protein is not the result of the presence of Campylobacter sp. or enterobacteria in the colon contents.  相似文献   
54.
Spinal epidural abscess: a ten-year perspective   总被引:14,自引:0,他引:14  
A retrospective study of spinal epidural abscess spanning 10 years and encompassing 40 patients was done. Epidemiology, clinical features, laboratory findings, radiographic imaging, therapy, and outcome were examined and compared with previous series. An increasing incidence of the disease (up to 1.96 patients per 10,000 admissions per year) and an older, more debilitated population (67% having factors predisposing them to infection) were discovered. Over half of the population was studied with magnetic resonance imaging, which was found to be equally as sensitive (91%) as myelography with computed tomography (92%). Magnetic resonance imaging offers the advantages of being noninvasive and able to delineate other entities, which makes it the imaging modality of choice. Preoperative paralysis and neurological deterioration from normal were identified as poor prognostic features. Of 7 patients with preoperative paralysis, 5 died, and the rest failed to recover neurological function. Eleven patients with initially normal neurological exams deteriorated in the hospital before surgical intervention. Eight of these patients were being treated with appropriate antibiotics; 2 became paralyzed despite more than 3 weeks of antibiotic therapy. Only 3 of these 11 patients recovered fully. Immediate surgical decompression combined with antibiotics remains the treatment of choice.  相似文献   
55.
Body pain and treatment response in late-life depression.   总被引:2,自引:0,他引:2  
OBJECTIVE: The authors investigated the influence of body pain on 1) time to treatment response and 2) suicidal ideation, in late-life depression. They hypothesized that higher levels of body pain would predict a longer time to and lower likelihood of response, and increased levels of suicidal ideation. METHODS: Subjects (N=187) were older adult outpatients (age > or =69 years), with current episodes of major depression, who were openly treated with paroxetine up to 40 mg daily and weekly interpersonal psychotherapy. Response was defined as 3 consecutive weeks of Hamilton Rating Scale for Depression at < or =10. Body pain was measured with the Bodily Pain Index of the SF-36 quality-of-life assessment. Authors used survival-analysis models on the responder sample to test the effect of body pain on response, after controlling for severity of depression. RESULTS: Overall response rate was 75.4%. Nonresponders reported more severe pain at baseline. After covarying for severity of baseline depression, no effect was found for physical pain on time-to-response or degree of suicidality. Bodily pain remained stable during acute treatment for responders, independent of depression response to combination psychotherapy and antidepressant treatment. CONCLUSIONS: Older adult patients with higher levels of physical pain can still respond to antidepressant treatment; however, reported bodily pain may be associated with a more difficult-to-treat depression.  相似文献   
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To date, despite very encouraging preclinical results, almost all phase II/III clinical neuroprotection trials in traumatic brain injury (TBI) have failed to show any consistent improvement in outcome for TBI patients. To understand the reasons behind such developments we need to review and evaluate the evolution of trial design as a result of our changing understanding of the pathophysiology of brain cell death and progress of translational research from the laboratory bench to the bedside. This paper attempts to critically appraise these neuroprotection trials, rationalize the paucity of effectiveness, review any recent developments in the field, and try to draw some conclusions on how to move forward.  相似文献   
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