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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
2.
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
3.
Calciphylaxis – a topical overview 总被引:3,自引:0,他引:3
G Arseculeratne† AT Evans‡ SM Morley† 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):493-502
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis. 相似文献
4.
5.
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
6.
7.
Twelve patients with progressive renal failure were placed on a very low protein diet supplemented by an essential amino acid-keto acid mixture for six to twelve months. Total daily intake was 0.04 g nitrogen/kg and 50 kcal/kg. Eight subjects had a significant change in the slope of reciprocal plasma creatinine, becoming less steep and in two cases positive. GFR did not improve, but in four patients the decline over twelve months was less than 0.5 mliter/min. There were significant falls in blood and urinary urea, serum phosphate PTH and calcium X phosphate product. Body wt decreased during the first three months. Arm muscle circumference fell by 0.9 cm (P less than 0.005). Serum albumin and transferrin levels did not change significantly. Muscle mass and plasma creatinine fell simultaneously in several patients. Creatinine excretion per kg muscle mass, assessed anthropometrically, declined by 21% in the first three months. This diet may slow the decline in renal function in a proportion of patients. However, muscle mass can be lost. Serum protein levels do not accurately reflect nutritional changes. A fall in plasma creatinine may not be due to improved GFR but instead to altered creatinine metabolism. 相似文献
8.
The aim of this study was to investigate the attitudes of doctors performing surgery to the HIV antibody testing of surgical patients. Fifty of eighty (62.5%) doctors performing surgery who are working in two London teaching hospitals returned completed anonymous postal questionnaires. Sixty-six per cent of the sample would like some form of compulsory testing of pre-operative patients, although most of them feel that this is only necessary for patients considered to be in 'high-risk groups'. Eighty-four per cent believe that this would ensure their safety from infection during surgery. Forty-eight per cent agreed with testing patients without their consent. Results suggest that most of the doctors performing surgery in this study agree with compulsory HIV antibody testing of pre-operative patients in the belief that this would protect them from infection during surgery. The problems associated with compulsory testing and relying on such testing in order to protect doctors from infection during surgery are discussed. 相似文献
9.
The purpose of this paper is to review the therapeutic applications of electrical stimulation and to focus on functional neuromuscular electrical stimulation (FES), which is the production of useful muscle contractions for joint stability and limb movement. The use of FES to improve patient function during the recovery period after illness or injury and the transition to FES neural prosthetic systems for patients who do not fully recover will be discussed. Emphasis will be given to the maintenance of posture and the production of purposeful movement from the perspective of technologies and clinical strategies that are available today and from the perspective of those technologies that have the potential for transfer to community health care in the near future. 相似文献
10.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献