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991.
Thomas JE Moossavi M Mehregan DR McFalda WL Mahon MJ 《International journal of dermatology》2004,43(11):785-789
BACKGROUND: Juvenile hyaline fibromatosis (JHF) is a rare, inherited condition characterized by tumor-like growth of hyalinized fibrous tissue on the head and neck, joint contractures, and gingival hypertrophy. There may be marked clinical heterogeneity. METHODS: We present a case of a 3-year-old Haitian boy with multiple firm nodules on the scalp and chin without joint contractures or gingival hypertrophy. Family history was not available. RESULTS: Biopsy specimens from three scalp nodules were processed with routine and immunohistochemical stains. The matrix was periodic acid Schiff (PAS) and Alcian blue positive. The cellular stromal component was positive for vimentin and scattered factor XIIIa positive cells were found. Osteoclast-like giant cells were also noted, and stained for CD68. CONCLUSIONS: Our patient had the nodular growths on the scalp and face that are characteristically found in JHF. Microscopic examination confirmed the diagnosis and showed scattered intracytoplasmic and extracellular eosinophilic globules in three separate biopsy specimens. These were positive with PAS. 相似文献
992.
At our Institute, a panel of reproductive hormones, viz., estrone glucuronide (E1G), pregnanediol glucuronide (PdG), luteinising hormone (LH), and follicle stimulating hormone (FSH) are estimated by ELISA for the assessment of fertility from a single urine sample collected from a subject. In order to make the estimates less cumbersome, the selection and mode of presentation of immunoreagents of the assay were modified in such a way that, either on reconstitution or single dilution, would result in ready-to-use reagents in the assay. Retrospective analysis on the performance of these ELISAs with uniform protocols (n = 86) was compared with assays having individual assay protocols (n = 116). The performance of the assay, based on the standard curve characteristics and quality control pools, was better and the rate of acceptance of these assays improved from 87.9 to 97.6%. The simplification of assay protocols, thus, had better impact on the quality and reproducibility of immunoassay of the four analytes. 相似文献
993.
Sarcoidosis is a multisystem granulomatous disease of unknown etiology, occasionally presenting with signs or symptoms that occur within the head and neck. The diagnosis may be made by a combination of histological evaluation of involved tissue, the presence of a relative cutaneous anergy, a positive Kveim test, and certain abnormal laboratory or radiographic findings. Although pulmonary sarcoidosis is by far the most common manifestation of the disease, an occasional patient will present with involvement of the nose, tonsils, larynx, or parotid gland. The otolaryngologist should include this entity in his differential diagnosis of lesions which occur in these areas. 相似文献
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995.
We studied the effect of aluminum on lead-induced nephropathy in male albino rats. Five groups of male albino rats were given either water only or lead acetate (125 mg/kg body weight) and/or aluminum chloride (50 mg/kg body weight or 100 mg/kg body weight) for a period of 90 days. Aluminum was found to prevent the lead-induced increase in the relative organ (kidney) weight in a dose-dependent manner. Aluminum also prevented lead-induced increase in plasma creatinine levels of the treated animals. Estimation of lead concentration in kidneys of different treatment groups revealed that the net deposition of lead was lower in animals which were given both lead acetate and aluminum chloride simultaneously. The results showed that aluminum offers some protection against lead-induced nephrotoxicity in a time- and dose-dependent manner. 相似文献
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PURPOSE: To examine peripheral nerve stimulation (PNS) thresholds for normal human subjects in magnetic resonance imaging (MRI) gradient coils, and determine if observed thresholds could be predicted based on gross physiologic measurements. MATERIALS AND METHODS: PNS thresholds for 21 healthy normal subjects were measured using a whole-body gradient coil. Subjects were exposed to a trapezoidal echo-planar imaging (EPI) gradient waveform and the total change in gradient strength (DeltaG) required to cause PNS as a function of the duration of the gradient switching time (tau) were measured. Correlation coefficients and corresponding P values were calculated for the PNS threshold measurements against simple physiologic measurements taken of the subjects, including weight, height, girth, and average body fat percentage, in order to determine if there were any easily observable dependencies. RESULTS: No convincing correlations between threshold parameters and gross physiologic measurements were observed. CONCLUSION: These results suggest it is unlikely that a simple physiologic measurement of subject anatomy can be used to guide the operation of MRI scanners in a subject-specific manner in order to increase gradient system performance while avoiding PNS. 相似文献
1000.
Toxicity of organophosphates stems mainly from the accumulation of acetylcholine due to inhibition of acetylcholinesterase (AChE). The consequences of excess acetylcholine depend on the events initiated by the interaction of acetylcholine with cholinergic receptors. Lipid peroxidation (LPO) induced by organophosphates also seems to be mediated via cholinergic receptors. Anilofos is a widely used thionoorganophosphate herbicide, while malathion is a thionoorganophosphate insecticide. Thionoorganophosphates undergo mixed function oxidase (MFO)-catalyzed bioactivation to oxons and can induce cholinergic crisis in mammals. Thus, factors (e.g. exposure to certain xenobiotics) which alter the MFO activity, can be assumed to affect the toxicity of these organophosphates. It was investigated in rats if malathion as an inhibitor of MFO can alter the toxicity of anilofos, examining certain biochemical traits in blood, brain and liver. Malathion or anilofos and their combination did not produce any obvious signs of toxicity. Malathion did not alter the anticholinesterase action of anilofos in blood, brain and liver. LPO was increased in erythrocytes, brain and liver with anilofos or malathion and their combination. Production of lipid peroxide in brain of malathion-pretreated rats given anilofos was significantly greater than in rats given anilofos alone. Malathion decreased glutathione (GSH) contents of liver and blood. Glutathione-S-transferase (GST) activity was decreased in the liver with malathion and its combination with anilofos. Total adenosine triphosphatase (ATPase) activity was not affected. Activities of Mg(2+)-ATPase and Na(+)-K(+)-ATPase were increased in the liver and erythrocytes, respectively, with the pesticide combination. Protein level in plasma was decreased with malathion and its combination with anilofos, but only with the combination in the liver. Results of the study indicate that malathion pretreament may not essentially alter the anticholinesterase action of anilofos, but may enhance anilofos-mediated oxidative damage to rat brain. 相似文献