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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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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
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M J Glynn J Powell-Tuck D A Reaveley I M Murray-Lyon 《JPEN. Journal of parenteral and enteral nutrition》1988,12(5):457-461
We have conducted a randomized double crossover study over 4 days in six parenterally fed patients with portasystemic encephalopathy (PSE) in which the nonprotein energy source of otherwise identical feeds was alternately all glucose or predominantly fat. Concentrations of plasma branched chain amino acids (BCAA), plasma insulin, and blood glucose were measured after an initial fast and subsequently after each of the four 24-hr periods of isonitrogenous feeding. The grade of PSE was assessed clinically and by the number connection test, BCAA concentrations were significantly lower during the glucose infusion than during fasting or the lipid infusion. PSE was significantly less with the lipid than with the glucose infusion. Trials testing the effect of infused BCAA must take account of the opposing effect on BCAA concentrations of simultaneous glucose infusion. A high lipid feed may have advantages in the short-term treatment of PSE. 相似文献
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Karen A Luker PhD BNurs RGN RHV NDNCert Kinta Beaver BA RGN DPSN Samuel J Leinster BSc MD FRCS R Glynn Owens BTech DipPsych DPhil AFBPsS Lesley F Degner PhD RN Jeffrey A Sloan PhD BSc 《Journal of advanced nursing》1995,22(1):134-141
Nurses can play a key role in patient education, including providing patients with useful and approrate information Rather than focusing on the process of education or information giving by nurses, this study places emphasis on the content of that information by taking the patients'perspective and asking the patients themselves what particular types of information are perceived as important at a specific point in time The aim of the study was to explore what particular types of information were important to women newly diagnosed with breast cancer, to enable nurses and other health care professionals to utilize their time as effectively as possible and provide a high-quality service to individuals in their care Women with breast cancer (a mean of 2 5 weeks from diagnosis) were interviewed and asked to compare items of information The items of information were presented m pairs and the women stated a preference for one item in that pan- Thirty-six pairs were presented in total The analysis involved the use of a Thurstone scaling model, which allowed rank ordermgs, or profiles of information needs, to be developed, reflecting the perceived importance of each item Information about the likelihood of cure, the spread of the disease and treatment options were perceived as the most important items of information at the tune of diagnosis Other information needs, in order of descending priority, included information about the risk to family, side-effects 相似文献
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Factors influencing women to undergo screening mammography 总被引:2,自引:0,他引:2
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Splenic T cells from myelin basic protein (MBP)-immunised Lewis rats were activated to transfer experimental autoimmune encephalomyelitis (EAE) by co-culture with MBP-pulsed lymphoid dendritic cells (DC). MBP-pulsed DC could be kept for at least 24 h at 37 degrees C in antigen-free medium without affecting their ability subsequently to activate encephalitogenic T cells. However, MBP-pulsed DC were rendered much less stimulatory after a 6 h, but not 2 h, secondary incubation with ovalbumin. Thus, although encephalitogenic complexes between MBP and DC appear very stable in the absence of competing antigens, in their presence, antigen exchange can take place over a period of a few hours; this has positive implications for therapy of EAE by antigen competition. 相似文献