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111.
Studies using magnetic resonance spectroscopy in human volunteers to evaluate their livers in vivo and to analyze their blood in vitro suggest that there are measurable amounts of silicon compounds in the blood of some women with implants and that there is migration of silicone to other organs such as the liver.  相似文献   
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Our objective was to test the hypothesis that internal medicine residents can be trained to screen for abdominal aortic aneurysm (AAA) using personal ultrasound imagers. We trained 5 randomly chosen internal medicine residents to image the abdominal aorta for patients with risk factors for AAAs using personal ultrasound imagers. Residents were trained in 3 or 4 one-on-one sessions with an instructor. To be eligible, patients had to be older than 65 years and have hypertension. After training, each of the 5 residents studied 3 patients independently. In 12 of the residents' 15 unsupervised studies, their abdominal aorta measurements were within 5 mm of the instructor's measurements with standard echocardiography (mean difference 3 mm, range 0-6 mm). Residents detected 3 previously unknown AAAs measuring 5.2, 4.2, and 3.9 cm in diameter. We conclude residents can be trained to image the abdominal aorta with personal ultrasound imagers and to identify AAAs in patients at risk.  相似文献   
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OBJECTIVE: To assess the distribution of cord blood insulin in an unselected population, and examine its relation to birthweight centiles. SETTING: District General Hospital in Nottinghamshire. SUBJECTS: 209 unselected singleton births. MEAN OUTCOME MEASURE: Cord blood insulin; cord blood C-peptide; birthweight centiles. RESULTS: Hyperinsulinaemic babies (greater than 97th centile for cord insulin) were found at all birthweight centiles. 15% of high birthweight babies were hyperinsulinaemic. For low birthweight babies, the distribution of cord insulin/C-peptide was skewed indicating a high number of low values. Hypoinsulinaemic babies were present up to the 50th centile for birthweight. CONCLUSIONS: Abnormalities of fetal insulinisation may be found in babies of all birthweights.  相似文献   
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The authors present two biopsy-proved cases of Creutzfeldt-Jakob disease. MR appears to be more sensitive than CT in detecting pathologic changes; signal abnormalities, when found, are predominantly within gray matter and may involve only peripheral cortex.  相似文献   
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Four selected cases of emergent IABP insertion in PV patients are presented. After angiographic documentation of critical iliac stenosis, conservative peripheral angioplasty was performed prior to IABP insertion. No patient experienced a peripheral ischemic event associated with IABP use. © 1992 Wiley-Liss, Inc.  相似文献   
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Children with the idiopathic nephrotic syndrome (NS) are known to be susceptible to bacterial infections. A recent report suggested that splenic hypofunction may be responsible for this immunological defect. We assessed splenic function by counting the circulating pocked red blood cells (PkRBCs) using interference phase contrast microscopy. PkRBCs are removed by the spleen, so that normal eusplenic individuals have less than 2% PkRBCs while asplenics have 15%–30%. Intermediate values are seen in hyposplenism. Thirty-three measurements of PkRBCs were made in 19 children with NS (mean age 7.5±0.8 years). PkRBCs were normal in all children tested (range 0–0.8%), including two patients with bacterial peritonitis associated with relapse. Thus we were unable to find evidence of hyposplenism in children with NS.  相似文献   
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BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs) effectively treat various anxiety disorders, although symptoms of anxiety are often exacerbated during early stages of treatment. We previously reported that acute treatment with the SSRI citalopram enhances the acquisition of auditory fear conditioning, which is consistent with the initial anxiogenic effects reported clinically. Here, we extend our findings by assessing the effects of acute SSRI treatment on the expression of previously acquired conditioned fear. METHODS: Rats underwent fear conditioning drug-free. Tone-evoked fear responses were tested after drug treatment the following day. This protocol more closely resembles the clinical setting than pre-conditioning treatment, because it evaluates effects of treatment on a pre-existing fear rather than on the formation of a new fear memory. RESULTS: A single pre-testing injection of the SSRIs citalopram or fluoxetine significantly increased fear expression. There was no effect of the antidepressant tianeptine or the norepinephrine reuptake inhibitor tomoxetine, indicating that this effect is specific to SSRIs. The SSRI-induced enhancement in fear expression was not blocked by tropisetron, a 5-HT(3) receptor antagonist, but was blocked by SB 242084, a specific 5-HT(2C) receptor antagonist. CONCLUSIONS: Enhanced activation of 5-HT(2C) receptors might be a mechanism for the anxiogenic effects of SSRIs observed initially during treatment.  相似文献   
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