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91.
BACKGROUND: Peritoneal dialysis (PD) and hemodialysis (HD) are both widely used as sole therapies for end-stage renal disease (ESRD). There is still controversy over which (if either) is superior in terms of patient outcomes. Peritoneal dialysis offers the advantages of long, slow, continuous ultrafiltration and potentially enhanced protection of residual renal function (RRF). In contrast, HD offers superior solute removal at the cost of undesirable cardiovascular tolerance of high rates of sodium and water removal. The aim of this study was to investigate the clinical feasibility of offering a combined treatment of both modalities [bimodal dialysis (BMD)] to incident patients reaching ESRD. We set out to investigate if it might be possible to utilize the intrinsic advantages of both modalities within a setting of good patient acceptability. METHODS: We prospectively studied 8 patients. They were recruited in the pre-ESRD phase from a specialist low clearance clinic. An arteriovenous fistula was formed and peritoneal catheters were inserted. The BMD consisted of 2, 3-hour, high efficiency, euvolemic HD sessions per week in combination with 2 PD exchanges per day to provide a degree of solute clearance and all of the ultrafiltration. Adequacy was measured independently for each modality. Patients were followed using the standard range of evaluations in addition to RRF (by creatinine clearance and EDTA clearance), echocardiography (left ventricular mass and ventricular performance), treatment outcomes, patient symptoms, and complications. RESULTS: Mean time on BMD was 346 +/- 74.9 (range 245 - 431) days. Peritonitis rate was 21 months per episode (mean 0.6 +/- 0.9, 0 - 2 episodes per patient). Mean peritoneal ultrafiltration volume was 1.58 +/- 0.32 (1.3 - 2.1) L per day. Delivered Kt/V and weekly PD Kt/V did not change significantly. Patients' RRF was maintained over the study period, as were serum albumin and control of serum phosphorus. Blood pressure was controlled with a reduction in the number of antihypertensive agents. Left ventricular mass index reduced over the treatment period, from a mean of 194 +/- 31.2 (161 - 265) to 156 +/- 21.2 (138 - 189) g/m2 (p = 0.05). Ventricular performance remained unchanged over the study [ejection fraction 50.4 +/- 11.1 (38 - 67) % to 48 +/- 8.0 (48 - 67) %]. Mean time during BMD spent on HD alone was 4.2 +/- 6.9 (0 - 16) days, and on PD alone 9.2 +/- 10.6 (0 - 25) days. CONCLUSION: This study suggests that BMD is a feasible treatment for ESRD. It is associated with adequate solute removal and good hemodynamic/volume control, and allows increased treatment flexibility for coping with complications normally requiring recourse to unplanned HD with temporary central venous access.  相似文献   
92.
OBJECTIVE: To assess the efficacy and safety of aripiprazole for psychosis associated with Alzheimer dementia (AD). METHODS: In this double-blind, multicenter study, 487 institutionalized patients with psychosis associated with AD were randomized to placebo or aripiprazole, 2, 5 or 10 mg/day. Primary efficacy assessment was the mean change from baseline to week 10 on the Neuropsychiatric Inventory-Nursing Home (NPI-NH) version Psychosis Subscale score. Secondary measures included NPI-NH Total, Clinical Global Impression-Severity of Illness (CGI-S), Brief Psychiatric Rating Scale (BPRS) Core and Total, and the Cohen-Mansfield Agitation Inventory (CMAI) scores. RESULTS: Aripiprazole 10 mg/day showed significantly greater improvements (mean change [2 x SD]) than placebo on the NPI-NH Psychosis Subscale (-6.87 [8.6] versus -5.13 [10.0]; F = 6.29, df = 1, 422, p = 0.013 by analysis of covariance [ANCOVA]); CGI-S (-0.72 [1.8] versus -0.46 [1.6]; F = 4.68, df = 1, 419, p = 0.031 [ANCOVA]); BPRS Total (-7.12 [18.4] versus -4.17 [21.6]; F = 4.72, df = 1, 399, p = 0.030 [ANCOVA]); BPRS Core (-3.07 [6.9] versus -1.74 [7.8]; F = 7.30, df = 1, 407, p = 0.007 [ANCOVA]); CMAI (-10.96 [22.6] versus -6.64 [28.6]; F = 5.23, df = 1, 410, p = 0.023 [ANCOVA]), and NPI-NH Psychosis response rate (65 versus 50%; chi(2) = 5.52, df = 1, p = 0.019 [CMH]). Aripiprazole 5 mg/day showed significant improvements versus placebo on BPRS and CMAI scores. Aripiprazole 2 mg/day was not efficacious. Cerebrovascular adverse events were reported: aripiprazole 2 mg/day, N = 1; 5 mg/day, N = 2; 10 mg/day, N = 4; placebo, N = 0. No deaths in any group (aripiprazole 2 mg/day, 3%; 5 mg/day, 2%; 10 mg/day, 7%; placebo, 3%) were considered to be treatment-related. CONCLUSION: Aripiprazole 10 mg/day was efficacious and safe for psychosis associated with AD, significantly improving psychotic symptoms, agitation, and clinical global impression. However, clinicians should be aware of the safety considerations of atypical antipsychotic uses in this population.  相似文献   
93.
Brain-dead donors are the major source of lungs for transplantation. Brain death is characterized by two hemodynamic phases. Initially, massive sympathetic discharge results in a hypertensive crisis. This is followed by neurogenic hypotension. Up-regulation of pro-inflammatory mediators occurs in all organs and lung injury develops; this can adversely affect graft function post-transplantation. The mechanisms of the systemic and lung inflammation are unknown. We hypothesized that the hemodynamic changes are responsible for these inflammatory phenomena. Brain death was induced by intra-cranial balloon inflation in rats. This resulted in hypertensive crisis, followed by hypotension. There was a significant increase in blood neutrophil CD11b/CD18 expression and pro-inflammatory cytokine levels in serum and bronchoalveolar lavage, compared with control animals. Rupture of the capillary-alveolar membrane was demonstrated by electron microscopy. Elimination of the hypertensive response by α-adrenergic antagonist pre-treatment prevented inflammatory lung injury, reduced the systemic inflammatory markers and preserved capillary-alveolar membrane integrity. Correction of the neurogenic hypotension with noradrenaline ameliorated the systemic inflammatory response and improved oxygenation. We conclude that the sympathetic discharge triggers systemic and lung inflammation, which can be further enhanced by neurogenic hypotension. Management of the brain-dead donor with early anti-inflammatory treatment and vasoconstrictors is warranted.  相似文献   
94.
PURPOSE: Obesity has become a health-care crisis in the United States. Adolescent obesity is now one of the most common childhood disorders, with 4.7 million American adolescents having a body mass index (BMI) greater than the 95th percentile. Most patients do not respond to diet modification or exercise programs and attention is now turning toward surgery as a source of weight loss in adolescents. Few studies have looked at the overall morbidity and mortality of weight loss surgery in this patient population. METHODS: This is a retrospective study of medical charts of 15 bariatric surgical procedures performed on 14 adolescents without known genetic syndromes associated with severe childhood obesity from 1971 to 2001 at the University of Minnesota. Procedures performed on these patients included vertical banded gastroplasty (n = 7), Roux-en-Y gastric bypass (n = 5), and jejunoileal bypass (n = 3). Jejunoileal bypass procedures were performed from 1971 to 1977, after which time this procedure was abandoned. Patient age ranged from 13 to 17 years (mean, 15.7 years). Mean follow-up time was 6 years, with 9 patients available for long-term follow-up. RESULTS: All procedures were performed using an open technique by 1 surgeon. There were no perioperative deaths; complications included 1 case of wound infection, 2 episodes of dumping syndrome that resolved without revision, 1 episode of hypoglycemia, and 1 case of short-term electrolyte imbalance in a patient who underwent jejunoileal bypass. The average BMI dropped from 58.5 +/- 13.7 to 32.1 +/- 9.7 kg/m(2) (P < .01)--a 45% reduction. CONCLUSIONS: Surgery for morbid obesity is safe and results in significant weight loss in adolescents who fail medical therapy.  相似文献   
95.
96.
97.
Evaluation of the thyroid nodule.   总被引:3,自引:0,他引:3  
BACKGROUND: Thyroid nodules are common, yet treatment modalities range from observation to surgical resection. Because thyroid nodules are frequently found incidentally during routine physical examination or imaging performed for another reason, physicians from a diverse range of specialties encounter thyroid nodules. Clinical decision making depends on proper evaluation of the thyroid nodule. METHODS: The current literature was reviewed and synthesized. RESULTS: Current evidence allows the formulation of recommendations and a general algorithm for evaluating the incidental thyroid nodule. CONCLUSIONS: Only a small percentage of thyroid nodules require surgical management. Diagnosis and treatment selection require a risk stratification by history, physical examination, and ancillary tests. Nodules causing airway compression or those at high risk for carcinoma should prompt evaluation for surgical treatment. In nodules larger than 1 cm, fine-needle aspiration biopsy is central to the evaluation as it is accurate, low risk, and cost effective. Subcentimeter nodules, often found incidentally on imaging obtained for another purpose, can usually be evaluated by ultrasonography. Other laboratory and imaging evaluations have specific and more limited roles. An algorithm for the evaluation of the thyroid nodule is presented.  相似文献   
98.
OBJECTIVES: To determine electrocardiogram (ECG) predictors of positive cardiac markers and short-term adverse cardiac events in an undifferentiated chest pain population presenting to emergency departments (EDs). The authors hypothesized that specific ECG findings, other than those previously identified in higher-risk populations, would be predictive of cardiac outcomes and positive cardiac markers. METHODS: This study used data from a prospectively collected, retrospectively analyzed Internet-based data registry of undifferentiated chest pain patients (i*trACS). Logistic regression modeling was performed to determine the ECG findings that were predictive of 1) positive cardiac markers and 2) short-term adverse cardiac events. RESULTS: ST-segment elevation (STE), ST-segment depression (STD), pathological Q-waves (PQW), and T-wave inversion were associated with increased odds of percutaneous coronary intervention or catheterization, myocardial infarction, or coronary artery bypass grafting. The odds of creatine kinase-MB (CK-MB) measuring positive were increased if STE, STD, or PQW were present [odds ratio (OR) 2.495, 2.582, and 1.295, respectively]. A right bundle branch block tended to decrease the odds of CK-MB measuring positive (OR 0.658). A similar pattern of results was observed for troponin I (OR 3.608 for STE, 3.72 for STD, 1.538 for PQW). Troponin T showed an increased odds of measuring positive if any of STE, STD, left bundle branch block, or T-wave inversion were evident (OR 2.313, 2.816, 1.80, and 1.449, respectively). CONCLUSIONS: Initial ECG criteria can be used to predict short-term cardiac outcomes and positive cardiac markers. These findings can be important aids in the risk-stratification and aggressive treatment regimens of chest pain patients presenting to EDs.  相似文献   
99.
OBJECTIVE: To examine the relationship between coil-cortex distance and effective cortical stimulation using transcranial magnetic stimulation (TMS) in the left and right motor cortex. We also compare the effect of coil-cortex distance using 50 and 70 mm figure-eight stimulating coils. METHODS: Coil-cortex distance was manipulated within each participant using 5 and 10 mm acrylic separators placed between the coil and scalp surface. The effect of cortical stimulation was indexed by resting motor threshold (MT). RESULTS: Increasing distance between the coil and underlying cortex was associated with a steep linear increase in MT. For each additional millimetre separating the stimulating coil from the scalp surface, an additional approximately 2.8% of absolute stimulator output (approximately 0.062 T) was required to reach MT. The gradient of the observed distance effect did not differ between hemispheres, and no differences were observed between the 50 and 70 mm TMS coils. CONCLUSIONS: Coil-cortex distance directly influences the magnitude of cortical stimulation in TMS. The relationship between TMS efficacy and coil-cortex distance is well characterised by a linear function, providing a simple and effective method for scaling stimulator output to a distance adjusted MT. SIGNIFICANCE: MT measured at the scalp-surface is dependent on the underlying scalp-cortex distance, and therefore does not provide an accurate index of cortical excitability. Distance-adjusted MT provides a more accurate index of cortical excitability, and improves the safety and efficacy of MT-calibrated TMS.  相似文献   
100.
Abstract:  We describe a patient with acquired alpha-thalassemia myelodysplastic syndrome (ATMDS). A previously healthy 66-year-old man presented with hemoglobin of 9.3 g/dL, mean corpuscular volume 59 fL, and a bone marrow aspirate with increased erythroid precursors and hypolobulated megakaryocytes. Hemoglobin H inclusions were seen in most red cells after 1% brilliant cresyl blue supravital stain of the peripheral blood. At the molecular level, we identified of a novel mutation in the most 3' exon of the ATRX gene ( C GA→ T GA substitution in codon 2407) resulting in a premature termination codon (p.R2407X). This case provides further evidence for a link between ATRX mutations and ATMDS, and suggests a possible role for the conserved Q-box element in ATRX function.  相似文献   
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