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71.
Solitary epithelioid histiocytoma (previously called reticulohistiocytoma) is a rare benign dermal histiocytic proliferation characterized by the presence of large, eosinophilic histiocytes with 'glassy' cytoplasm. This entity assumes importance because of its close histologic resemblance to several benign as well as malignant cutaneous lesions. Involvement of the penis is extremely rare, and to our knowledge, only one case has been previously described in the literature. We report a case of solitary epithelioid histiocytoma in a 34-year-old man who presented with a nodule in the glans penis. Microscopy showed proliferation of large epithelioid histiocytes with abundant eosinophilic cytoplasm, which expressed CD68, CD163 and vimentin. This case highlights the significance of recognizing this unusual lesion and differentiating it from its histologic mimics.  相似文献   
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10 male subjects with chronic liver disease and with normal cardiovascular findings, except for the presence of a presystolic gallop, underwent right and left heart catheterization. In general, all of the patients had a high resting cardiac output, narrow arteriovenous oxygen difference, a low peripheral vascular resistance, and normal left ventricular end-diastolic pressures and volumes. The plasma volume was increased in the seven patients in which it was determined.On exercise, all of the patients demonstrated a significant increase in the left ventricular end-diastolic pressure and mean pulmonary artery pressure, while the stroke index remained the same or fell in seven of the subjects.It appears logical to assume that the excessive intake of alcohol is associated with an impairment in the metabolic and contractile properties of the left ventricle and the resultant hemodynamic effects may not be readily discerned in the resting state. However, upon exercise these patients, with a congested circulation, can show abnormal cardiac dynamics.  相似文献   
74.
Metallothionein, a low molecular weight cadmium-binding protein, has been determined for the first time in urine of “itai-itai” disease patients and other Japanese women environmentally exposed to cadmium. On a group basis, the urinary metallothionein levels of “itai-itai” disease patients and suspected patients were significantly higher than that of women living in a cadmium-polluted area. Women living in a non-polluted area excreted significantly less metallothionein than women living in a cadmium-polluted area. A similar trend was observed for urinary β2-microglobulin, a non-specific index of renal tubular dysfunction. However, mean levels of urinary cadmium in the “itai-itai” disease patients, suspected patients and women living in the cadmium-polluted area were similar. It is suggested that if, in addition to β2-microglobulin and cadmium, metallothionein is used as another index of cadmium exposure, monitoring of renal tubular dysfunction caused by cadmium may be more effectively carried out.  相似文献   
75.
Hydroxychloroquine (HCQ) is widely used in the treatment of systemic lupus erythematosus (SLE). Even if it is generally agreed that pregnancy per se increases disease activity in patients with SLE and that withdrawal of HCQ at the onset of pregnancy may result in exacerbation of SLE, use of HCQ during pregnancy has remained controversial for a long time. Parke was the first to propose continuation of HCQ throughout gestation. Currently, more than 250 pregnancies resulting in live births have been reported and no increase in the rate of birth defects have been demonstrated. When studied, no retinal toxicity and ototoxicity have been found. Data concerning lactation and HCQ treatment are rare. However, the amount of HCQ received by children through lactation seems very low. In conclusion, HCQ should probably be maintained throughout pregnancy in patients with SLE and it does not seem necessary to advise against breastfeeding.  相似文献   
76.
Valproic acid (VPA) is a broad-spectrum antiepileptic drug and is usually well tolerated, but rare serious complications may occur in some patients receiving VPA chronically, including haemorrhagic pancreatitis, bone marrow suppression, VPA-induced hepatotoxicity (VHT) and VPA-induced hyperammonaemic encephalopathy (VHE). Some data suggest that VHT and VHE may be promoted by carnitine deficiency. Acute VPA intoxication also occurs as a consequence of intentional or accidental overdose and its incidence is increasing, because of use of VPA in psychiatric disorders. Although it usually results in mild central nervous system depression, serious toxicity and even fatal cases have been reported. Several studies or isolated clinical observations have suggested the potential value of oral L-carnitine in reversing carnitine deficiency or preventing its development as well as some adverse effects due to VPA. Carnitine supplementation during VPA therapy in high-risk patients is now recommended by some scientific committees and textbooks, especially paediatricians. L-carnitine therapy could also be valuable in those patients who develop VHT or VHE. A few isolated observations also suggest that L-carnitine may be useful in patients with coma or in preventing hepatic dysfunction after acute VPA overdose. However, these issues deserve further investigation in controlled, randomized and probably multicentre trials to evaluate the clinical value and the appropriate dosage of L-carnitine in each of these conditions.  相似文献   
77.
Immunopathogenesis of Erdheim-Chester disease (ECD), a rare non-Langerhans cell histiocytosis, is poorly known. In previous studies, various cytokines were detected in ECD lesions, presumably orchestrating lesional histiocyte recruitment. Because ECD lesions are frequently associated with systemic symptoms, we postulated that underlying global immune perturbations might also be revealed. We quantitatively analyzed 23 cytokines in serum samples obtained from a large single-center cohort of 37 patients with ECD, and studied the impact of treatment on cytokine production. IL-6, IL-12, interferon-α (IFN-α), and monocyte chemotactic protein-1 (MCP-1) levels were significantly higher in untreated patients than in controls, whereas interferon-γ (IFN-γ) inducible protein 10, IL-12, MCP-1, and IL-1 receptor antagonist were found significantly increased in IFN-α-treated patients. A biomathematical approach was used to rationalize multiparameter data, to generate new hypotheses, and identify global control pathways. Interestingly, cytokine profiles proved to be particularly stable at the individual level, and an "ECD signature" further distinguished patients from controls, based on their production of IFN-α, IL-12, MCP-1, IL-4, and IL-7. Altogether, our data underline the systemic immune Th-1-oriented perturbation associated with this condition and provide clues for the choice of more focused therapeutic agents in this rare disease with noncodified therapeutic management.  相似文献   
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A novel method is presented for the three‐dimensional mapping of the B1‐field of a transmit radio‐frequency MR coil. The method is based on the acquisition of phase images, where the effective flip angle is encoded in the phase of the nonselective hard pulse excitation. The method involves the application of a rectangular composite pulse as excitation in a three‐dimensional gradient recall echo to produce measurable phase angle variation. However, such a pulse may significantly increase the radio‐frequency power deposition in excess of the standard acceptable SAR limits, imposing extremely long TRs (>100 msec), which would result in acquisition times significantly greater than a single breath‐hold. In this study, the phases of the radio‐frequency excitation are modified, resulting in a different pulse sequence scheme. It is shown that the new method increases sensitivity with respect to radio‐frequency inhomogeneities by up to 10 times, and reduces the total duration of the pulse so that three‐dimensional B1 mapping is possible with 3He in lungs within a single breath‐hold. Computer simulations demonstrate the increase in sensitivity. Phantom results with 1H MRI are used for validation. In vivo results are presented with hyperpolarized 3He in human lungs at 1.5T. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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