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101.
Dapsone is a drug commonly used in the treatment of various dermatological diseases. Here, we report the case of a 45-year-old female prescribed dapsone for chronic urticaria after which she developed extensive livedo reticularis in the limbs, abdomen, and trunk. The use of dapsone may be associated with a plethora of adverse effects including rash but livedo reticularis has been very rarely reported. Emphasis should be laid on the possible drug etiology in any patient who develops new signs and symptoms while on medications, even if it may not be supported by enough literature.KEY WORDS: Chronic urticaria, Dapsone, livedo reticularis, rash  相似文献   
102.
Amyloidosis, a heterogenous group of disorders, is characterized by the extracellular deposition of autologous, insoluble, fibrillar misfolded proteins. These extracellular proteins deposit in tissues aggregated in ß-pleated sheets arranged in an antiparallel fashion and cause distortion to the tissue architecture and function. In the current literature, about 60 heterogeneous amyloidogenic proteins have been identified, out of which 27 have been associated with human disease. Classified as a rare disease, amyloidosis is known to have a wide range of possible etiologies and clinical manifestations. The exact incidence and prevalence of the disease is currently unknown. In both systemic and localized amyloidosis, there is infiltration of the abnormal proteins in the layers of the gastrointestinal (GI) tract or the liver parenchyma. The gold standard test for establishing a diagnosis is tissue biopsy followed by Congo Red staining and apple-green birefringence of the Congo Red-stained deposits under polarized light. However, not all patients may have a positive tissue confirmation of the disease. In these cases additional workup and referral to a gastroenterologist may be warranted. Along with symptomatic management, the treatment for GI amyloidosis consists of observation or localized surgical excision in patients with localized disease, and treatment of the underlying pathology in cases of systemic amyloidosis. In this review of the literature, we describe the subtypes of amyloidosis, with a primary focus on the epidemiology, pathogenesis, clinical features, diagnosis and treatment strategies available for GI amyloidosis.  相似文献   
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The echocardiographic features in seven patients with flail aortic leaflets are described and are correlated with the anatomical appearance of the valve at the time of surgery or autopsy. M-mode echocardiography showed coarse and "shaggy" diastolic echoes within the aortic root and thickening of the aortic leaflets during systole in all patients. Six patients had coarse and "shaggy" diastolic echoes within the left ventricular outflow tract in continuity with similar echoes within the aortic root. Cross-sectional echocardiography in three patients revealed a cord-like mass prolapsing into the left ventricular outflow tract during diastole. Three of the patients had no vegetations at the time of surgery. Both modes of echocardiography are of value in demonstrating abnormal echoes prolapsing into the left ventricular outflow tract, characteristic of flail aortic leaflets that can occur in the presence or absence of vegetations.  相似文献   
105.
BACKGROUND & AIMS: Studies comparing long-term success after pneumatic dilatation (PD) and laparoscopic Heller myotomy (HM) are lacking. This study compares long-term outcome of PD (single dilatation and graded approach) and laparoscopic HM and identifies risk factors for treatment failure. METHODS: A cross-sectional follow-up evaluation of an achalasia cohort treated between 1994 and 2002 was followed-up for a mean of 3.1 years. There was a total of 106 patients treated by graded PD (1-3 dilatations with progressively larger balloons) and 73 patients treated by HM (20 had failed graded PD and crossed over to HM). A symptom assessment (structured telephone interview or clinic visit) was performed and patients were given freedom from alternative therapies to determine treatment outcome. Endoscopy, manometry, and timed barium esophagram were performed to determine the cause of treatment failure. RESULTS: The success of single PD was defined as freedom from additional PDs: 62% at 6 months and 28% at 6 years (risk factors for failure: younger age, male sex, wider esophagus, and poor emptying on posttreatment timed barium esophagram). Freedom from subsequent PDs increased with each dilatation (graded PD). The success of graded PD and HM, defined as dysphagia/regurgitation less than 3 times/wk or freedom from alternative treatment, was similar: 90% vs 89% at 6 months and 44% vs 57% at 6 years (no risk factors for failure were identified). Causes of symptom recurrence were incompletely treated achalasia (96% after PD vs 64% after HM) and gastroesophageal reflux disease (4% after PD vs 36% after HM). CONCLUSIONS: No treatment cures achalasia. Short- and long-term success is similar for graded PD and laparoscopic HM. Therapeutic success decreases steadily over time. Achalasia patients need careful long-term follow-up evaluation.  相似文献   
106.
A number of neuroimaging findings have been interpreted as evidence that the left inferior frontal gyrus (IFG) subserves retrieval of semantic knowledge. We provide a fundamentally different interpretation, that it is not retrieval of semantic knowledge per se that is associated with left IFG activity but rather selection of information among competing alternatives from semantic memory. Selection demands were varied across three semantic tasks in a single group of subjects. Functional magnetic resonance imaging signal in overlapping regions of left IFG was dependent on selection demands in all three tasks. In addition, the degree of semantic processing was varied independently of selection demands in one of the tasks. The absence of left IFG activity for this comparison counters the argument that the effects of selection can be attributed solely to variations in degree of semantic retrieval. Our findings suggest that it is selection, not retrieval, of semantic knowledge that drives activity in the left IFG.  相似文献   
107.
The role of lipoxygenase metabolites of arachidonic acid as inflammatory mediators of endotoxin shock remains uncertain. In this study the effect of LY171883, a selective leukotriene D4/E4 antagonist, on the hemodynamic alterations of endotoxin shock was assessed. Adult male rats were given an intraperitoneal injection of LY171883 (30 mg/kg) or vehicle 10 minutes prior to intravenous injection of endotoxin (15 mg/kg) or vehicle. Cardiac output, mean arterial pressure, and multiple organ blood flows were determined at 30 minutes after endotoxin or vehicle administration with 85Sr-radiolabeled microspheres. Cardiac output decreased from 32.1 +/- 2.7 ml/min/100 g in the control group to 16.3 +/- 2.7 ml/min/100 g in endotoxin-treated animals (P less than .05). Pretreatment with LY171883 blunted significantly (P less than .05) this fall in cardiac output (26.3 +/- 2.6 ml/min/100 g). Endotoxin reduced mean arterial pressure from 95 +/- 8 mm Hg in controls to 57 +/- 8 (P less than .05), which was not, however, different from control values in rats receiving the LTD4/E4 antagonist. There was also significant (P less than .05) blunting of the endotoxin-induced fall in blood flow to the heart, gastrointestinal tract, and kidneys in animals pretreated with LY171883. Our data demonstrate that this selective leukotriene D4/E4 antagonist has significant salutary actions in endotoxin shock and suggest that LTD4 and/or E4 mediate, in part, the acute hemodynamic sequelae of endotoxin shock.  相似文献   
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110.
Primary malignant cardiac lymphomas associated with grafts are extremely rare: to our knowledge, only 6 cases of prosthesis-associated B-cell lymphoma have been reported. Ours is the first report of recurrent diffuse large B-cell lymphoma associated with aortic valve allografts.We treated a 60-year-old man who presented in early 2007 with aortic valve endocarditis. He underwent aortic valve replacement with an allograft; the resected native valve showed active endocarditis without tumor. In January 2011, the patient underwent repeat aortic valve replacement because of symptomatic aortic regurgitation. The explanted valve specimen displayed diffuse large B-cell lymphoma. In September 2011, the patient presented with fever and a mass around the aortic valve. He died in January 2012. On autopsy, the explanted replacement valve displayed recurrent diffuse large B-cell lymphoma. The recurrent lymphoma on a new graft leads us to believe that this tumor is more aggressive than had been thought. We propose early systemic chemotherapy, in addition to tumor resection, for the possibility of a better prognosis. We discuss our patient''s case and review the relevant medical literature.  相似文献   
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