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1.
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
2.
The second part of this review addresses the treatment and prognosis of the vasculitides Wegener's granulomatosis, microscopic
polyangiitis, Churg–Strauss syndrome and polyarteritis nodosa. Treatment regimens consist of an initial remission phase with
aggressive immunosuppression, followed by a more prolonged maintenance phase using less toxic agents and doses. This review
focuses on the initial treatment of fulminant vasculitis, the mainstay of which remains immunosuppression with steroids and
cyclophosphamide. For Wegener's granulomatosis and microscopic polyangiitis plasma exchange can be considered for first-line
therapy in patients with acute renal failure and/or pulmonary haemorrhage. Refractory disease is rare and is usually due to
inadequate treatment. The vasculitides provide a particular challenge for the critical care team. Particular aspects of major
organ support related to these conditions are discussed. Effective treatment has revolutionized the prognosis of these conditions.
However, mortality is still approximately 50% for those requiring admission to intensive care unit. Furthermore, there is
a high morbidity associated with both the diseases themselves and the treatment. 相似文献
3.
Thomas L. Patterson Shirley J. Semple Lydia R. Temoshok J. Hampton Atkinson J. Allen McCutchan Kristy A. Straits-Trster James L. Chandler Igor Grant 《Journal of Applied Biobehavioral Research》1993,1(1):64-87
The significance of life stress, coping, and social support was examined in relation to depressive symptomatology in a sample of 160 asymptomatic and mildly symptomatic HIV-antibody-positive (HIV+) men. The participants (mean age = 32 years) were interviewed about the life stress that they had experienced in the previous 6 相似文献
4.
Paediatric dacryocystorhinostomy 总被引:1,自引:0,他引:1
KN Hakin FRCS FRCOphth TJ Sullivan FRACO FRACS A Sharma FCOphth † RAN Welham FRCS FCOphth † 《Clinical & experimental ophthalmology》1994,22(4):231-235
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease. 相似文献
5.
Granulomatous Pneumocystis carinii pneumonia in a patient with the acquired immunodeficiency syndrome. 总被引:2,自引:2,他引:0 下载免费PDF全文
A patient with an unusual granulomatous response to infection with Pneumocystis carinii is described. The diagnosis was made by open lung biopsy after two negative bronchoalveolar lavages. 相似文献
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Monaural inhibition in cat auditory cortex 总被引:13,自引:0,他引:13
9.
Factors influencing women to undergo screening mammography 总被引:2,自引:0,他引:2
10.
P Coni G Pichiri-Coni G M Ledda-Columbano E Semple S Rajalakshmi P M Rao D S Sarma A Columbano 《Cancer letters》1992,61(3):233-238
The present study was undertaken to determine the effect of two different types of liver cell proliferative stimuli, namely compensatory regeneration and direct hyperplasia on DNA synthesis of normal and preneoplastic isolated hepatocytes. Platelet-poor plasma (PPP) isolated from male Wistar rats treated with three different hepato-mitogens, lead nitrate (LN), cyproterone acetate (CPA) and ethylene dibromide (EDB), or subjected to surgical partial hepatectomy (PH), was tested for its ability to stimulate DNA synthesis in normal and preneoplastic hepatocytes in primary cultures. Induction of DNA synthesis was detected as early as 30 min after CPA, EDB and PH administration and persisted up to 5 days after the LN administration. In addition, hepatocytes isolated from preneoplastic liver nodules were also able to respond in culture to the DNA synthesis stimulus induced by these factors. 相似文献