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991.
992.
The 3G5-reactive ganglioside antigen (3G5 antigen) is expressed on the surface of various cell types including pericytes, pancreatic islet cells, thyroid follicular cells, and cells of the pituitary and the adrenal medulla. Expression on melanocytes has not yet been reported. We examined 148 5-microm cryosections of 12 normal skin samples and 45 skin tumors (21 melanocytic nevi, 8 malignant melanoma primaries, 4 metastases of malignant melanoma, 3 basal cell carcinomas, and 9 pigmented seborrheic keratoses) by triple fluorescence technique with the monoclonal antibody 3G5, DNA fluorochrome, and the anti-melanocytic antibody A103 (Anti-Melan-A). In normal skin, 3G5 reactivity was detected in epidermal melanocytes of 4 of 12 cases with 14.8 +/- 24.1% positive melanocytes; 20 of 21 nevi (72.2 +/- 29.1% positive nevus cells, mean +/- SD), 8 of 8 primary melanomas (83.9 +/- 12.3% positive melanoma cells), and 4 of 4 melanoma metastases (82.5 +/- 6.5% positive melanoma cells) expressed the 3G5 antigen. All tumor cells of investigated basal cell carcinoma or seborrheic keratosis were 3G5 negative. This is the first report of 3G5 antigen expression in melanocytes. The data demonstrate high expression of this ganglioside in the aggregated melanocytes of malignant or benign tumors but low or absent expression in singular melanocytes (normal epidermis, seborrheic keratoses) reflecting a different biologic state.  相似文献   
993.
We describe dyschromatosis universalis in a 19-month-old Saudi Arabian girl. She had no associated defects and none of the other family members were affected. Similar cases reported from countries other than the Far East, where the disease was first described, are discussed.  相似文献   
994.

Objective  

To compare phototherapy devices based on their physical and photo-biological characteristics viz spectral properties, maximum and mean irradiance, treatable percentage of body surface area, decay of irradiance over time and in vitro photoisomerisation of bilirubin.  相似文献   
995.
996.
Medication neurotoxicity may have a variety of imaging manifestations in children. In this pictorial essay, we review the two most common brain injury patterns, posterior reversible encephalopathy syndrome (PRES) and acute toxic leukoencephalopathy (ATL). Proposed etiologies, salient features on neurological imaging, and methods for differentiating these entities and their implications will be discussed. Certain agents do not fall into these two broad patterns but instead characteristically involve central structures. We individually review several medications and their respective neurotoxic appearances including methotrexate, cyclosporine A, tacrolimus, metronidazole and vigabatrin. Diagnosis of medication neurotoxicity may be achieved by the combination of new-onset neurological deficits, recent initiation of a new therapy agent and distinctive findings on magnetic resonance imaging. Clinical and radiological improvement and/or resolution are frequently observed after the agent is discontinued.  相似文献   
997.

Background  

Pediatric body MRI exams often cover multiple body parts, making the development of broadly applicable protocols and obtaining uniform fat suppression a challenge. Volumetric T2 imaging with Dixon-type fat-water separation might address this challenge, but it is a lengthy process.  相似文献   
998.
Two adult patients of leprosy, one woman and one man, presented with a clinical picture simulating sporotrichosis. The skin and regional nerve trunk was affected in one, and in the other the disease was confined to the nerve. Both had features of an upgrading reaction following anti-leprosy therapy; this was seen as erosion and scarring of the plaque, and acute onset of abscesses along the easily palpable and thickened nerve that ruptured through the skin. The diagnosis was supported by histopathology. In the light of other infections that give rise to a sporotrichoid pattern of infection it is concluded that leprosy should also be included in this category so that early diagnosis and use of corticosteroids can be implemented quickly to prevent nerve destruction.  相似文献   
999.
Chanarin–Dorfman syndrome is a rare congenital disorder of lipid metabolism characterized by ichthyosis, leukocytic vacuolation (Jordan's anomaly), and variable involvement of the liver and neuromuscular system, with about 40 cases described worldwide to date. We report one more case of this rare syndrome, with certain peculiarities, namely vacuolation in eccrine glands, in a young male adult.  相似文献   
1000.
One hundred patients with secondary skin tuberculosis--59 with lupus vulgaris (LV), 27 with scrofuloderma (SD), and 14 with tuberculosis verrucosa cutis (TVC)-were included in this study. The buttocks and lower limbs were seen to be important sites of involvement in LV, besides the occurrence over the face. An active focus of tuberculosis was present in 18, a past history of pulmonary tuberculosis in 8, and intrafamilial tuberculous infections in 21. Histopathology and culture for Mycobacterium tuberculosis were done in all the cases. Guinea pig inoculation was done in 11. The poor results of these investigations have been highlighted and discussed with reference to studies done in the past by other workers. The need for improvement in laboratory techniques is suggested.  相似文献   
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