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1.
Changing attentional demands in left hemispatial neglect. 总被引:1,自引:0,他引:1
R F Kaplan M Verfaellie M E Meadows L R Caplan M S Pessin L D DeWitt 《Archives of neurology》1991,48(12):1263-1266
Seven variations of a letter cancellation test were used to examine how varying attentional demands affect hemispatial neglect in patients with right hemisphere lesions. While the 14 targets always remained in the same location, the number of distractors (zero, nine, 28, or 82) as well as their complexity (one letter or nine different letters) were varied. The percentage of targets canceled in the left hemispace was linearly related to the number of distractors. There were no differences between the complexity conditions. In a second study, the same 14 targets were presented but the distractors (zero, 14, or 41) were all placed on the right. Increasing the number of distractors on the right increased neglect on both sides of the space. Taken together, these results suggest that, while the limited attentional resources of the left hemisphere are biased toward the right hemispace, the absence of contralateral attentional demands allows these resources to be directed ipsilaterally. 相似文献
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M R Hamre L L Robison M E Nesbit H N Sather A T Meadows J A Ortega G J D'Angio G D Hammond 《Journal of clinical oncology》1987,5(11):1759-1765
The Childrens Cancer Study Group has assessed serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), and pubertal development in 97 long-term female survivors of childhood acute lymphoblastic leukemia (ALL). All patients received identical induction and maintenance therapy with either 18 or 24 Gy of radiation therapy (RT) to one of the following fields: cranial, craniospinal, or craniospinal plus 12 Gy abdominal RT including the ovaries. Thirty-six percent (35 patients) were found to have above normal levels of FSH and/or LH. The percentages of elevated values for RT fields were 93% for craniospinal plus abdominal RT, 49% for craniospinal RT, and 9% for cranial RT (P less than .001). A dose-response relationship was observed between 18 Gy and 24 Gy in females receiving only craniospinal RT (P = .01). Craniospinal plus abdominal RT and abnormal FSH/LH levels were significantly associated with lack of pubertal development and delayed onset of menses. Duration of maintenance chemotherapy was not associated with abnormal gonadotropin levels or the development of secondary sexual characteristics. Additional follow-up of this cohort is needed to establish the ultimate pubertal development and fertility of these patients. 相似文献
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The role of surgery in abdominal non-Hodgkin's lymphoma: experience from the Childrens Cancer Study Group. 总被引:4,自引:0,他引:4
M P LaQuaglia C J Stolar M Krailo P Exelby S Siegel A Meadows D Hammond 《Journal of pediatric surgery》1992,27(2):230-235
To determine the appropriate role of surgical intervention in non-Hodgkin's lymphoma primary to the abdomen, we analyzed the effect of multiple prognostic determinants on event-free survival for patients entered into the CCG-551 study. Eighty-four patients were identified with abdominal lymphoma and of these adequate data for analysis was available on 68 (81%). Variables of interest included: extent of disease at diagnosis, completeness of resection, use of bowel resection, radiation to the primary site, and sex/age/race. The median age on study was 8 years; 79% of patients were white and 85% were male. Thirty-three patients (49%) presented with localized disease. Laparotomy was performed in 67 children (99%) with complete gross resection in 28 (42%). Of the 10 reported surgical complications, 8 occurred in those with extensive disease who were incompletely resected. Radiation to the primary site was given in 60% of patients with median dose of 2,000 cGy. Analysis was performed both for the overall group and for the subgroup receiving optimal chemotherapy for histopathology. Variables with significant predictive effect on event-free survival in univariate analysis included extent of disease (P less than or equal to .001), complete resection (P less than or equal to .002), and use of bowel resection (P less than or equal to .004). However, in multivariate analysis, only extent of disease was an independent predictor of outcome. The data support a role for complete operative excision of localized lymphomas especially when accomplished with bowel resection. Aggressive attempts at debulking extensive retroperitoneal or mesenteric lymphomas are contraindicated. 相似文献
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P A Nathan R C Keniston L D Myers K D Meadows 《JAMA》1992,268(6):787; author reply 787-787; author reply 780
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A randomized controlled trial of electromagnetic therapy in the primary care management of venous leg ulceration 总被引:1,自引:1,他引:0
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care. 相似文献
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