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1.
Burkitt's lymphoma, characterized by jaw and abdominal tumors, is the most common early childhood malignancy in Central Africa and well-known in the United States, with only sporadic reports coming from other countries. Considered to be the fastest growing tumor in man, it is thought to be of viral etiology with warm, humid climate and malaria regarded as co-factors. This is the first case of Burkitt's lymphoma reported from Greece.  相似文献   
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Summary In this study we attempted to extend our previous results on regional specialization of frontal cortical function in humans, by means of magnetoencephalography (MEG). We used a verbal task and predicted that some part of the left frontal lobe would be active during engagement in that task, since the left hemisphere is known to be implicated in language. We did not require a motor response because in previous experiments we observed bilateral frontal magnetic activity, and we suspected that it was due to the addition of movement-related fields to our recordings. Six right handed subjects (three males and three females) participated in the study. The task consisted in silently counting the number of word pairs that matched with respect to semantic category. Experimental runs were composed by series of 120 trials or word pairs. All six subjects presented dipolar magnetic field distributions on the left fronto-temporal area of the scalp, but not on the right, during different portions of the trial duration. These fields were successfully modeled as equivalent current dipoles (ECDs). The spatial ECD coordinates were translated onto magnetic resonance image (MRI) coordinates for each subject. The dipole positions were typically near the cortical surface corresponding to areas 6 and 44 of Brodmann. No dipole-like sources were observed in the right frontal lobe.This research was supported by grant NS 29540-005A1 from the National Institutes of Health, Washington, D.C.  相似文献   
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Cytomegalovirus (CMV) infection is a major cause of morbidity and mortality after hematopoietic stem cell transplantation. Significant progress has been made in the prevention of CMV disease over the past decade, but prevention of late CMV disease continues to be a challenge in selected high-risk populations. The pretransplantation CMV serostatus of the donor and/or recipient remains an important risk factor for posttransplantation outcome despite the use of antiviral prophylaxis and preemptive therapy; CMV-seropositive recipients of T cell-depleted grafts in particular continue to have a survival disadvantage compared with seronegative recipients with seronegative donors. The risk of developing antiviral drug resistance remains low in most patients; however, in a setting of intense immunosuppression (eg, after transplantation from a haploidentical donor), the incidence may be as high as 8%. Primary CMV infection via blood transfusion can be reduced by the provision of seronegative or leukocyte-depleted blood products; however, a small risk of 1% to 2% of CMV disease remains. Surveillance and preemptive therapy are effective in preventing the sequelae of transfusion-related CMV infection. Indirect immunomodulatory effects of CMV are increasingly recognized in hematopoietic stem cell transplant recipients. Strategies currently being investigated include long-term suppression of CMV with valganciclovir for the prevention of late CMV infection and disease, adoptive transfer of CMV-specific T cells, and donor and recipient vaccination strategies.  相似文献   
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As part of a multicenter, collaborative project, response to fenfluramine was assessed in 10 autistic outpatients. After 4 months of treatment, blood serotonin concentrations decreased an average of 60 per cent and returned to pretreatment levels after 2 months on placebo. This reduction was accompanied by a decrease in certain behavioral symptoms, including motor activity, distractibility, and mood disturbances. Baseline evoked potential recordings indicated that autistic patients tended to have a larger amplitude of the P3 component to frequent tones as compared to age-matched controls. A tendency toward "normalization" of the P3 effect was observed during the medication trial and during the final placebo period. Treatment response was not related to initial serotonin levels, and no major clinical side effects were associated with fenfluramine.  相似文献   
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The magnetic flux normal to the scalp surface was measured with a whole-head neuromagnetometer while right-handed subjects (N = 15) were engaged in either an auditory word- or a tone-recognition task. Sources of the recorded magnetic fields were modeled as equivalent current dipoles at 4 ms intervals and the number of sources in the later portion of the magnetic response was used as an index of the degree of brain activation. Significantly more sources were found in the left as compared to the right hemisphere in the word but not the tone task on a group basis. On an individual basis, 13/15 subjects had more sources in the left as compared to the right hemisphere during the word task, while in the tone task 3/10 subjects showed this pattern. Sources of activity were found in the left superior and middle temporal gyri in all subjects with available MRI scans. Sources were also found in the supramarginal gyrus and in medial temporal areas, including the hippocampus, in the majority of cases. MEG appears to be a promising tool for detecting activity in cerebral areas specialized for language and memory function.  相似文献   
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Objective Elevated plasma homocysteine has been implicated in vascular changes compatible with atherosis and endothelial dysfunction similar to the vascular changes of the placenta in preeclampsia. Previous reports have indicated an increased incidence of hyperohomocysteinemia in preeclamptic patients. The aim of this study was to examine the association of homocysteine levels and preeclampsia in our patients. Study design Prospective study of 28 preeclamptic patients that were matched with 26 normal controls of the same gestational age. Results The preeclamptic group had an increased incidence of cesarean sections (75%), of growth retarded fetuses (50%), intrauterine deaths (7%) and placental abruptions (7%). Mean levels of homocysteine were significantly elevated in the preeclamptic than in control group (11.11 vs. 6.40 μmol/l, P < 0.001). There were no differences between the groups regarding the levels of folic acid (11.12 vs. 9.73 ng/ml, P = 0.55) and vitamin B12 (295.76 vs. 356.15 pg/ml, P = 0.43). Conclusion It is concluded that in our study homocysteine levels are significantly elevated in patients with preeclampsia compared with control group, while no vitamin deficiencies were observed.  相似文献   
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This is a report of ten consecutive patients with end-stage cardiac disease treated with orthotopic cardiac transplantation in a community hospital, during the first year of its heart transplantation program. All patients were followed for a minimum of 33 months and a maximum of 45 months with 100% survival at two years and 90% at three years. All survivors are presently in N.Y.H.A. Class I or II. The entire group of patients received the same triple immunosuppressive therapy. The incidence of infection and rejection during the first three months post-transplantation was 0.3 and 0.6 episodes per patient respectively. Every patient developed some degree of deterioration in renal function and 80% of the patients now receive treatment for systemic hypertension. The in-hospital institution cost for the transplant admission varied from $25,084 to $74,164. To date, 30 patients have undergone heart transplantation in our program and 26 are long-term successes. This study again proves that renal insufficiency and hypertension remain the major side effects of Cyclosporine therapy. We further conclude from our experience that cardiac transplantation can be successfully and cost effectively performed in a community hospital even with a somewhat lower caseload.  相似文献   
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Clinical features such as weight gain, depression, hypertension, and menstrual irregularities, although common in the general population, may raise the possibility of Cushing's syndrome. Up to 30% of urine cortisol and dexamethasone suppression screening tests may return an incorrect result, suggesting that better tests are needed. This study evaluated the utility of nighttime salivary cortisol measurement as a screening test for Cushing's syndrome. We evaluated 139 inpatients and 4 outpatients with possible Cushing's syndrome, 16 inpatients and 7 outpatients with other nonadrenal disorders, and 34 healthy outpatients. Using cut points that excluded all subjects without Cushing's syndrome, we compared the sensitivity for the detection of Cushing's syndrome of nighttime salivary cortisol levels (2330 and 2400 h for inpatients and bedtime for outpatients), simultaneous inpatient serum cortisol levels, and urine glucocorticoid excretion. An assay- specific inpatient 2400-h salivary cortisol or an outpatient bedtime salivary cortisol greater than 550 ng/dl (15.2 nmol/liter) identified 93% of patients with Cushing's syndrome (confidence interval, 89-98%) and excluded all individuals without the disorder. Salivary cortisol measurements worked as well as plasma measurements and better than urine glucocorticoid excretion. We concluded that bedtime salivary cortisol measurement is a practical and accurate screening test for the diagnosis of Cushing's syndrome.  相似文献   
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