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A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.  相似文献   
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We used the latency of the P1 cortical auditory-evoked potential (CAEP) as a biomarker for the development of central auditory pathways in three children who received intervention through hearing aids and/or cochlear implants. Our goal was to examine the clinical feasibility of using the latency of the P1 CAEP as an objective tool to evaluate whether acoustic amplification for hearing-impaired children has provided sufficient stimulation for normal development of central auditory pathways. If clinicians have such a marker, then they can more confidently make a decision about whether to provide a child with a cochlear implant following an appropriate hearing-aid trial. Using the same marker, clinicians will also be able to monitor the maturation of central auditory pathways once electrical stimulation is initiated.  相似文献   
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Background Patients with prostate cancer with a pre-operative prostate-specific antigen (PSA) τ;15ng/ml who undergo radical retropubic prostatectomy (RRP) generally do not have a good outcome, yet may have organ-confined cancer and should be offered the option of surgery. Aim To assess the outcome of patients who underwent RRP with a pre-operative PSA ≥ 15ng/ml. Methods Thirty-four patients, mean pre-operative PSA: 25.46ng/ml (15.03–76.6) and mean Gleason score: 6.4 (5–9) were assessed. Results Two groups were identified. Group I: 41% (14/34) have no biochemical recurrence to mean follow up of 58 months (30–106). Mean PSA: 18.8ng/ml (15.03–25.84). Mean Gleason score: 6.1 (5–7). Clinical stage: T1c in 80%. No patient had seminal vesicle or lymph node involvement. Group II: 59% (20/34) have biochemical recurrence or died (3) from their disease to mean follow up of 66 months (36–98). Mean PSA: 28.9ng/ml (15.28–76.6). Mean Gleason score: 6.7 (5–9). Clinical stage: T1c in 25%. Eleven patients had seminal vesicle (8) involvement or positive lymph nodes (3) or both (2). Conclusion RRP seems feasible in patients whose pre-operative PSA is between 15 and 25ng/ml with stage T1c, Gleason score ≤ 7 and negative lymph node frozen section.  相似文献   
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BACKGROUND: Chronic stress has been associated with impaired episodic memory, but the association of premorbidly experienced distress with memory function in Alzheimer's disease is unknown. OBJECTIVE: To investigate the link between proneness to distress and Alzheimer's disease. METHODS: Participants were 363 persons with clinically diagnosed Alzheimer's disease. At baseline, a knowledgeable informant rated each person's premorbid personality (that is, before dementia onset) along five dimensions, one of which was the tendency to experience psychological distress. Participants underwent structured clinical evaluations at baseline and then annually for up to four years. Each evaluation included 17 cognitive tests from which previously established measures of episodic memory, visuoconstruction, repetition, and naming were derived. RESULTS: In a series of random effects models adjusted for age, sex, and education, premorbid distress proneness was associated with baseline impairment in episodic memory but not with impairment in other cognitive domains, or with change in any cognitive domain. No other trait was related to baseline function or rate of decline in any cognitive domain. CONCLUSIONS: The results suggest that premorbid proneness to experience psychological distress is related to level of impairment in episodic memory in persons with Alzheimer's disease, but neither distress proneness nor other personality traits are related to disease progression.  相似文献   
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The combination of high-dose busulfan (16 mg/kg) and 200 mg/kg cyclophosphamide is gaining increasing significance as a preparative regimen prior to autologous, syngeneic, or allogeneic marrow transplantation. A new regimen of high-dose busulfan in conjunction with a reduced dose of 120 mg/kg cyclophosphamide has recently been described as a preparative regimen prior to allogeneic transplantation. To determine the drug-related nonhematologic toxic effects of this new regimen without confounding factors associated with allogeneic transplantation, we conducted a pilot study using this new regimen in 20 patients with acute myeloid leukemia (AML) in first remission prior to autologous unpurged marrow transplantation. All patients experienced transient non-life-threatening acute drug-related toxicity with skin reactions in 20 (100%), nausea and vomiting in 20 (100%), oral mucositis in 18 (90%), hepatic functional impairment in 17 (85%), hemorrhagic cystitis in three (15%), and generalized seizures in two (10%) of these patients, respectively. Two procedural, fatal complications resulted from infectious causes that were not directly related to the speed of hematopoietic reconstitution or the toxicity of the preparative regimen. The 3-year event-free survival estimate (55% +/- 11%) and probability of leukemic recurrence (38% +/- 11%) attained with this new regimen in recipients of autografts in first remission of AML are promising and challenge comparisons with preparative regimens employing combinations of cytotoxic agents or total body irradiation (TBI).  相似文献   
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Summary The pathophysiology and clinical significance of high signal lesions, visualized on magnetic resonance imaging (MRI) in patients with Alzheimer's disease (AD), remain controversial. Since they are known to correlate with vascular disease and vascular risk factors, we reviewed the clinical correlates of periventricular high signal (PVH) and subcortical white matter lesions (WML) in a sample of 106 patients with probable AD, excluding persons with treated vascular risk factors or symptomatic cerebrovascular and cardiovascular disease. Grade 2 PVH were seen in 26 (25%) and scattered WML were identified in 29 (18%). PHV were associated with advancing age and gait disturbance. WML were associated with gait disturbance and incontinence. Neither radiologic finding was related to dementia severity. The findings suggest that these lesions are common in patients with AD even when those with evidence of cerebrovascular disease are excluded; their presence, therefore, should not preclude a diagnosis of AD. Additionally, the data suggest that HSL on MRI may be one of many risk factors associated with functional disability in persons with probable AD.  相似文献   
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