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61.
Regional myocardial dysfunction: evaluation of patients with prior myocardial infarction with fast CT 总被引:1,自引:0,他引:1
Lipton MJ; Farmer DW; Killebrew EJ; Bouchard A; Dean PB; Ringertz HG; Higgins CB 《Radiology》1985,157(3):735-740
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
62.
Rosas M Attie F Pastelin G Lara A Velazquez O Tapia-Conyer R Martinez-Reding J Mendez A Lorenzo-Negrete A Herrera-Acosta J 《Kidney international. Supplement》2005,(97):S112-S119
BACKGROUND: A number of cross-sectional or serial studies have demonstrated the clinical impact of microproteinuria and macroproteinuria by identifying individuals at risk of both end-stage renal disease and major cardiovascular events. This study focused on the prevalence of proteinuria in Mexico and its relationship with other cardiovascular risk factors such as hypertension, type 2 diabetes mellitus, body mass index, smoking, age, and gender. METHODS: The prevalence of proteinuria in Mexico was obtained from the probabilistic cross-sectional national health survey performed in the year 2000. The proportion of urine dipstick samples that tested positive for protein (defined as > or =1+) in adults from 20 to 69 years of age was determined. The analysis was performed using both algebraic and multicategorical models. Potential interactions between proteinuria and other major cardiovascular risk factors were investigated. RESULTS: A total of 46,523 adult survey participants were included in the analysis. In the general population, 9.2% had proteinuria. By univariate, multivariate, and multicategorical analysis, hypertension, diabetes, obesity, and age were strongly associated with the prevalence of proteinuria (P < 0.001). However, in Mexico, the specific distribution of age groups demonstrated that the absolute number of patients without hypertension that had proteinuria is not irrelevant. To identify 1 case of proteinuria, one would need to screen 3 persons with diabetes mellitus, 5 patients with hypertension without diabetes, or 6 persons over the age of 55 years. When proteinuria is present, the probability of having a noncommunicable chronic disease or other major cardiovascular risk factor is more than 85%. CONCLUSION: Proteinuria is prevalent. When considered together, dipstick-positive proteinuria, blood pressure level, body mass index > or =30 m(2)/kg, and abnormal fasting blood glucose measured on a single occasion identifies different segments of the population. Studies such as this may be a suitable initial clinical approach to general population screening for renal and cardiovascular risk stratification. 相似文献
63.
A number of surgical clips and other metallic materials embedded within patients have ferromagnetic properties that present a potential hazard when in the strong fields associated with magnetic resonance imaging. Several types of magnetometers and metal detectors were investigated as possible pre-imaging screening devices. The sensitivities and costs of these devices are given. 相似文献
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65.
Guevara R Velazquez JL Nenadovic V Wennberg R Senjanovic G Dominguez LG 《Neuroinformatics》2005,3(4):301-314
Phase synchrony analysis is a relatively new concept that is being increasingly used on neurophysiological data obtained through different methodologies. It is currently believed that phase synchrony is an important signature of information binding between distant sites of the brain, especially during cognitive tasks. Electroencephalographic (EEG) recordings are the most widely used recording technique for recording brain signals and assessing phase synchrony patterns. In this study, we address the suitability of phase synchrony analysis in EEG recordings. Using geometrical arguments and numerical examples, employing EEG and magnetoencephalographic data, we show that the presence of a common reference signal in the case of EEG recordings results in a distortion of the synchrony values observed, in that the amplitudes of the signals influence the synchrony measured, and in general destroys the intended physical interpretation of phase synchrony. 相似文献
66.
Velazquez EF Barreto JE Rodriguez I Piris A Cubilla AL 《International journal of surgical pathology》2004,12(2):139-146
Surgeons often perform small or superficial penile biopsies that are difficult to classify definitely with regard to a benign or malignant nature, and if malignant, cannot always be accurately subclassified. Staging and therapeutic decisions rely on the identification, in these materials, of pathologic parameters related to prognosis. In this study, we evaluated the accuracy and completeness of pathologic information obtained from biopsies of 57 consecutive patients with squamous cell carcinoma (SSC) of the penis, and compared it with the information obtained from penectomies. Diagnostic accuracy was determined by recording discordances of critical factors in biopsies and penectomies. The evaluated parameters were as follows: cancer diagnosis, histologic type, tumor grade, depth of invasion (anatomical levels), and vascular invasion. Histologic subtypes of SCC were the following: usual 37, verruciform 11, mixed 7, pseudohyperplastic 1, and sarcomatoid 1. Grades were 1, 2, and 3 (well, moderately and poorly differentiated). Levels of invasion were lamina propria, corpus spongiosum, and corpus cavernosum in the glans; and lamina propria, dartos, and skin in the foreskin. In 2 patients with well-differentiated tumors a diagnosis of cancer could not be established in biopsy material. In 17 cases (30%) there was a biopsy-penectomy discordance of histologic types, especially of verruciform and mixed carcinomas. Biopsies failed to identify the correct histologic grade in 30% of the cases. A higher grade was usually identified in penectomy specimens. Because biopsies were superficial, the deepest point of invasion could not be determined in 91% of the cases. Vascular invasion was identified in biopsies in only 1 of 8 patients. In summary, biopsies were useful for cancer diagnosis except in 2 differentiated variants of penile squamous cell carcinoma. However, important pathologic parameters related to prognosis were missed on biopsy materials, and they were more accurately evaluated in penectomy specimens. We conclude that clinical and pathologic staging of penile cancer, at least in our material, cannot depend on biopsy information alone. Data from biopsies may be insufficient to make a decision whether to perform a groin dissection, or for prognostic evaluation in those patients in whom other treatment modalities (such as radiotherapy or chemotherapy) are being considered. 相似文献
67.
Background Sequentially evolving intracranial bilateral haematomas, where the second haematoma develops after the surgical removal of
the first one is rarely reported.
Aim To report a patient who developed an epidural haematoma after evacuation of a contralateral subdural haematoma.
Methods A 49-year-old male was admitted to our department after head injury. A brain computerized tomography (CT) scan revealed an
acute subdural haematoma in the right temporal area which was evacuated. During his stay in the intensive care unit, he was
submitted to intracranial pressure monitoring, which soon rose.
Results A new CT scan showed an acute epidural haematoma in the contralateral parietal area that was also evacuated.
Conclusions While rising intracranial pressure after the evacuation of a traumatic haematoma is usually attributed to brain oedema or
recurrent haematoma at the craniotomy site, the development of a contralateral epidural haematoma requiring surgical treatment
should not be overlooked. 相似文献
68.
Jamerson KA Bakris GL Wun CC Dahlöf B Lefkowitz M Manfreda S Pitt B Velazquez EJ Weber MA 《American journal of hypertension》2004,17(9):793-801
Reducing blood pressure (BP) to target levels is a major priority in preventing clinical events in hypertension. Typically this requires more than one drug, and recent guidelines on hypertension management therefore recommend starting with combination treatment in many patients. Diuretics have often been part of such therapy, usually paired with angiotensin converting enzyme (ACE) inhibitors or similar agents; but calcium channel blockers are also highly efficacious in reducing BP when combined with ACE inhibitors. In addition, these drug classes, separately and in combination, appear to have vasculoprotective properties. Because the primary goal of treating hypertension is to enhance survival and reduce cardiovascular outcomes, the Rationale and Design of Avoiding Cardiovascular events through COMbination therapy in Patients LIving with Systolic Hypertension (ACCOMPLISH) trial is designed as the first blinded and randomized study to prospectively compare the effects on these endpoints of two antihypertensive combinations, benazapril/hydrochlorothiazide (force titrated to 40/12.5 mg) and amlodipine besylate/benazapril (force titrated to 5/40 mg). The doses can be further titrated to 40/25 mg or 10/40 mg, and other classes of drugs can be added as needed for optimal BP control. The primary study endpoint is a composite of cardiovascular mortality and morbidity. The study will be performed in hypertensive patients (systolic BP > or = 160 mm Hg or currently on antihypertensive therapy) with risk factors for cardiovascular events (prior events, target organ damage, kidney disease, or diabetes). A total of 6300 subjects will be randomized to each group with the expectation that a total of 1642 primary endpoints will occur during a 5-year period, providing 90% power to detect the 15% relative reduction in events (alpha = 0.05) hypothesized to favor the amlodipine besylate/benazapril group. The ACCOMPLISH study will be performed in the United States and Europe. The first patient was randomizedduring 2003, and the trial should conclude in 2008. 相似文献
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70.