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Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography 总被引:2,自引:0,他引:2
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study. 相似文献
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Melinda S. Lantz 《Current Psychosis and Therapeutics Reports》2004,2(1):7-12
Depressive symptoms in older adults are common, but the minority of elderly meet criteria for major depressive disorder. This
has led to confusion regarding the recognition of diagnosis, approach to treatment, and monitoring of outcomes in this needy
population. Few depressed older adults are willing to seek treatment from psychiatrists or mental health specialists. Treatment
approaches to the depressive spectrum of disorders in late life, which encompasses major and minor depressive disorder, dysthymic
disorder, and mood disorders related to medical conditions, must include evidence-based algorithms that can be delivered in
a variety of health care settings. Several recent multisite trials have advanced the use of collaborative care models and
the systematic stepwise approach to the treatment of depression and anxiety states in older adults. This offers the ability
to provide effective treatment of depression for older adults, consistent with current guidelines, in primary care and specialized
health care settings. 相似文献
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Short-term niflumic-acid-induced acute renal failure in children 总被引:1,自引:0,他引:1
Lantz B.; Cochat P.; Bouchet J. L.; Fischbach M. 《Nephrology, dialysis, transplantation》1994,9(9):1234-1239
Several reports emphasize the adverse effects of non-steroidalanti-inflammatory drugs (NSAIDs) on renal function. We haveobserved over the last 10 years seven cases of acute renal failure(ARF) due to immune interstitial nephritis in children. A recommendedoral or rectal dose of niflumic acid was prescribed for ear-nose-throatdisorders, Length of exposure was 15 days. Clinical symptoms (oedema, oliguria or anuria) appeared between3 and 6 days. Three patients had previously received the drug.Hypersensitivity signs (fever, skin rash, eosinophilia, and/orincreased IgE) were present in all cases, leukocyturia in fivecases, and haematuria in six cases. Renal biopsy showed interstitiallesions with lymphocyte, eosinophil, and plasma cell infiltrateswithout tubular cell necrosis. Glomeruli were normal on light-microscopy,except in one patient. Electron-microscopy showed extensivepodocyte fusion in two patients, who had clinical and laboratoryevidence of nephrotic syndrome (NS). ARF rapidly disappeared after NSAID withdrawal, except in twopatients whose renal failure was irreversible despite methylprednisolonebolus. ARF is very rare in children treated with niflumic acid.When ARF occurs, different pathophysiological mechanisms areinvolved but the most common is immunological. 相似文献
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Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
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Objective . To describe the importance of migraine in Santiago, Chile, by analyzing its prevalence, clinical features and impact by age, gender and socioeconomic status. Methods . In 1993, a representative sample of 1,540 adults of the province of Santiago were interviewed using a standard questionnaire. A total of 1,385 (89.9%) subjects responded to the survey. Initially, a designated member of each household responded to the questionnaire. Subsequently, each household member with headaches was asked to respond to questions about severity, frequency, location, duration, associated symptoms and impact in work and social activities of their most frequent headaches. Migraine diagnoses were determined in accordance with the International Headache Society (IHS) criteria of 1988. Results. Recurrent headaches in the past year were found in 516 (36.82%) respondents, 145 (28.1%) males and 371 (71.9%) females. Total prevalence of migraine was found to be 7.3% (95%, CI 5.9–8.6); 11.9% (95% CI 9.6–14.2) in females and 2.0% (95% CI 0.9–3.0) in males. Overall, migraine constituted 19.6% (101/516) of all headaches reported in this sample. The prevalence did not vary significantly by age groups or socioeconomic status (SES). Migraine with aura had an overall prevalence of 3.5% (CI 0.8–7.1), and was significantly more frequent in females. In 60–70% of cases the attacks lasted 2–6 h and the frequency was 3.3 and 3.4 per month in females and males respectively. Both males and females reported significantly high percentages of attacks during work. Conclusions . Migraine prevalence in a sample of adults of Santiago is similar to that reported in previous studies using IHS criteria. Women of all socioeconomic levels are at an increased risk. 相似文献
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