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991.
Jeremy H. Jones Morag Attaie Sanjay Maroo David Neumann Rebecca Perry Malcolm D. C. Donaldson 《Pediatric radiology》2010,40(5):725-731
Background
Thyroid imaging is of proven help in establishing a diagnosis of congenital hypothyroidism in infants. US often shows tissue in the thyroid fossa when radionuclide scintigraphy reveals only ectopic uptake. 相似文献992.
993.
Long-term results of irradiation for patients with progressive Graves' ophthalmopathy. 总被引:3,自引:0,他引:3
S D Marquez B L Lum I R McDougall S Katkuri P S Levin M MacManus S S Donaldson 《International journal of radiation oncology, biology, physics》2001,51(3):766-774
PURPOSE: To determine the long-term outcome of radiotherapy (RT) in patients with progressively symptomatic thyroid eye disease and to evaluate the potential long-term sequelae. METHODS AND MATERIALS: Four hundred fifty-three patients provided written informed consent and received retrobulbar RT for Graves' ophthalmopathy at Stanford University Medical Center; 197 with 1 year of follow-up were retrospectively analyzed. Of the 197 patients, 189 received RT to the bilateral retrobulbar regions, and 4 received unilateral RT. The technical information was unavailable for 4 patients. Patients were assessed by chart review, telephone interview, questionnaire, and multidisciplinary physician examination. Eye impairment was scored using the SPECS system. The end point review included the before and after treatment SPECS score, surgical intervention, and patient satisfaction. Potential complications, including cataract development, retinopathy, and tumor formation, were investigated. Multivariate analyses were performed to assess the prognostic variables. RESULTS: Improvement or resolution was 89% for soft-tissue findings; 70% for proptosis; 85% for extraocular muscle dysfunction; 96% for corneal abnormalities; and 67% for sight loss. The response to RT may take >6 months to stabilize. Factors predictive of response varied in the individual SPECS categories but included the initial SPECS score, pretreatment thyroid status, female gender, a 20-Gy RT dose, and a history of hypertension. Nonpredictive factors included a history of tobacco use, diabetes mellitus, steroids, and prior cataracts. Only 16% required surgical intervention to preserve their vision or restore binocular vision. Twenty-two patients (12%) developed cataracts after irradiation (median 11 years). No patient developed a tumor within the RT field during the follow-up period (range 1-29 years). Ninety-eight percent of patients were pleased with their results, and 2% believed their symptoms progressed despite RT. CONCLUSIONS: Retrobulbar irradiation (20 Gy) is safe and effective treatment for progressive Graves' ophthalmopathy, with a 96% overall response rate, 98% patient satisfaction rate, and no irreparable long-term sequelae, with follow-up extending 29 years. The most common late effect observed was cataract development, which occurred more frequently in older patients and was reversible with extraction. Elective surgical intervention after RT should be withheld until patients have demonstrated a plateau in response. 相似文献
994.
Risk factors for adverse outcomes of bacterial meningitis 总被引:4,自引:0,他引:4
K GRIMWOOD TM NOLAN L BOND VA ANDERSON C CATROPPA EH KEIR 《Journal of paediatrics and child health》1996,32(5):457-462
Objective : To identify risk factors for adverse outcomes from bacterial meningitis.
Methodology : From a cohort of 166 children with bacterial meningitis who were studied prospectively, 130/158 (82%) survivors underwent neurological, neuropsychological, audiological and behaviour assessments 5–9 years following their illness.
Results : Major adverse outcomes included 8/166 (4.8%) deaths and severe neurological, intellectual or audiological sequelae in 11/130 (8.5%) children followed. Another 24 (18.5%) had cognitive, auditory or behaviour disorders. Bivariate analysis found age ≤12 months, tertiary referral, symptoms >24 h before diagnosis, seizures, focal neurological signs, deteriorating conscious state in hospital, Streptococcus pneumoniae infection and serum sodium concentration < 130 mmol/L were associated with adverse outcomes. Multivariate analysis showed age ≤12 months, symptoms >24 h, seizures after 72 h in hospital and focal neurological signs as independent risk factors. These were present in 18/19 (95%) children with major sequelae, but absent in 9/24 (37.5%) children with minor disabilities.
Conclusions : As minor disabilities following meningitis cannot be predicted, all survivors require assessment during their early school years. 相似文献
Methodology : From a cohort of 166 children with bacterial meningitis who were studied prospectively, 130/158 (82%) survivors underwent neurological, neuropsychological, audiological and behaviour assessments 5–9 years following their illness.
Results : Major adverse outcomes included 8/166 (4.8%) deaths and severe neurological, intellectual or audiological sequelae in 11/130 (8.5%) children followed. Another 24 (18.5%) had cognitive, auditory or behaviour disorders. Bivariate analysis found age ≤12 months, tertiary referral, symptoms >24 h before diagnosis, seizures, focal neurological signs, deteriorating conscious state in hospital, Streptococcus pneumoniae infection and serum sodium concentration < 130 mmol/L were associated with adverse outcomes. Multivariate analysis showed age ≤12 months, symptoms >24 h, seizures after 72 h in hospital and focal neurological signs as independent risk factors. These were present in 18/19 (95%) children with major sequelae, but absent in 9/24 (37.5%) children with minor disabilities.
Conclusions : As minor disabilities following meningitis cannot be predicted, all survivors require assessment during their early school years. 相似文献
995.
The present study examines the social influences in the Asian-American and European-American adolescent environment to provide a greater understanding of effect of ethnic differences on the prevalence of substance abuse. Participants were 957 Asian-American and 3705 European-American seventh grade adolescents. It was found that Asian-American students were less likely to use alcohol and cigarettes, and had a more abstinence-promoting environment than European-American adolescents. This difference in Asian-American adolescents appeared to be the result of less adult and peer influence to use alcohol or cigarettes, less offers of alcohol, and an increased likelihood of having an intact family when compared to European-American adolescents. Additionally, Asian-American adolescents reported having fewer friends and spending less time with their friends than European-American adolescents. It was concluded that social influences play an important role in explaining why Asian-American adolescents have lower rates of substance use. 相似文献
996.
Lall GS Walsh RM Rowlands DC Donaldson I 《The Journal of laryngology and otology》1999,113(6):585-586
Schwannoma of the tonsil is an extremely uncommon clinical entity with only one reported case in an adult in the medical literature to date. We report, to our knowledge, the first known case in a child. 相似文献
997.
OBJECTIVE: This study was conducted to assess the extent to which developing and implementing clinical practice guidelines for listing children for tonsillectomy (with or without adenoidectomy) influenced the behaviour of participating ENT surgeons. METHOD: A before and after study in which the intervention (the development and dissemination of local practice guidelines) was introduced sequentially into different hospitals and surgical practice. The study was conducted in four ear, nose, and throat surgical services in the North of England, with 16 consultant ENT surgeons and their junior staff on 1190 children aged 0 to 14 years who were judged, prior to consultation with an ENT surgeon, to have been referred for throat-related problems for which tonsillectomy was one possible treatment option were included in the study. Decision reached by surgeons and proportion of decisions that complied with new guidelines. RESULTS: Of the clinical decisions to list children for tonsillectomy taken before introduction of locally agreed guidelines, 73% (486/660) conformed to the criteria in the subsequent guidelines, 15% (97/660) did not, and in 12% (77/660), it was impossible to judge. After the intervention, the corresponding figures were 73% (386/530), 14% (73/53), and 13% (71/530), respectively. When decisions were taken to break the guidelines, this was more often to list for tonsillectomy when it was not indicated--83% (141/170)--than to withhold tonsillectomy when it was indicated--17% (29/170). The aspects of guidelines that were breached in decisions to carry out tonsillectomy were: the age of the child was younger than the guidelines recommended--54% (75/141); there had been fever attacks of tonsillitis than the guidelines recommended--22% (32/141); and there were "significant" symptoms not included in the guidelines--20% (29/141). CONCLUSIONS: In spite of strong evidence to the contrary, local guidelines were formulated at a level that the majority of surgeons already attained. Guideline development and implementation, therefore, had very little impact on clinical practice. The process of local formulation of guidelines was not sufficient to achieve change toward evidence-based practice; clinical preference proved to be quite intractable. There is a need to enhance the ability of clinicians in the assessment and interpretation of research evidence. Previous work has emphasized the need to explore factors that influence clinical behaviour toward evidence-based practice. Our study suggests the need for more research into why clinicians continue to follow clinical preference even when invited to base agreed local clinical policies on evidence. 相似文献
998.
MD Donaldson PH Thomas JG Love GD Murray AW McNinch DC Savage 《Archives of disease in childhood》1994,70(3):214-218
The presentation, pattern of acute illness, and incidence of learning difficulties are described in 63 (33 boys, 30 girls) children with salt wasting 21-hydroxylase deficiency, drawn from a cohort study of congenital adrenal hyperplasia in the South West Region of England between 1968 and 1988. Thirty boys presented with a salt losing crisis from birth whereas the other three boys presented between 2 and 14 months of age with failure to thrive and hyponatraemia. Diagnostic uncertainty led to 13 (43%) of 30 girls developing a salt losing crisis. Five girls were misassigned as boys at birth. There were four deaths in the group, two due to salt losing crisis, one to complications of prematurity possibly compounded by 21-hydroxylase deficiency, and one from heart failure probably related to an excess of steroids. Acute admissions were common, especially during the first year of life, with convulsions in 7% of admissions. The 9% incidence of hypoglycaemia was considered to be an underestimate as blood glucose was measured in only 56 (22%) of 254 admissions. No convulsions occurred in the 38 (15%) admissions where the parents had given intramuscular hydrocortisone before bringing the child to hospital. A high incidence of learning difficulties was found among the 59 surviving children (9/30 (30%) boys and 6/29 (21%) girls), and in only two children could any factor other than 21-hydroxylase deficiency be invoked. Analysis of the subgroup with learning difficulties indicated that they were more ill at presentation with a significantly higher incidence of hypoglycaemia, and that growth in the first year was significantly worse. It is concluded that congenital adrenal hyperplasia remains a formidable disorder with an appreciable mortality and morbidity. The high incidence of learning difficulties seen in salt wasting 21-hydroxylase deficiency needs further attention. A prospective study is indicated to examine the effect of neonatal screening on morbidity from congenital adrenal hyperplasia, particularly the intellectual impairment seen in this study. 相似文献
999.
1000.
Karen L. Donaldson Gay Lynn Goolsby Alan F. Wahl 《International journal of cancer. Journal international du cancer》1994,57(6):847-855
The overt effects of the anti-cancer drugs cisplatin (cis-DDP) and taxol appear to be DNA modification and microtubule stabilization respectively, yet the mechanisms by which these drugs elicit tumor cell death are not well understood. In this report cell sensitivities to cis-DDP and taxol were accurately determined as a function of cell proliferation and cell cycle stage. Quiescent fibroblasts restimulated to synchronously enter the cell cycle become maximally sensitive to cis-DDP immediately preceding DNA synthesis, and resistance increases with onset of DNA synthesis. Mid-log proliferating cells were separated into progressive stages of the cell cycle by centrifugal elutriation or by double thymidine (dThd) block. Cells staged by either method are maximally sensitive to cis-DDP in G1, just prior to the onset of DNA synthesis and minimally sensitive in peak DNA synthesis, with entry into S phase resulting in a 2-fold decrease in sensitivity. Cells that remained blocked at the G1/S phase boundary during cis-DDP treatment remain maximally sensitive after release. Sensitivity to taxol increases at 2 points: transiently during transition of normal cells from quiescence to proliferation and steadily as proliferating cells progress from early G1 to late G2. This 3-fold increase in taxol sensitivity through the cell cycle is rapidly reversed upon cell division. Synchronous cells treated with either drug at points of maximum sensitivity initiate apoptotic DNA fragmentation 12-14 hr post-exposure to drug. © 1994 Wiley-Liss, Inc. 相似文献