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81.
82.
Janneke Wit Torsten Nygaard Kristensen Pernille Sarup Jane Frydenberg Volker Loeschcke 《Experimental gerontology》2013
Drosophila melanogaster is frequently used in ageing studies to elucidate which mechanisms determine the onset and progress of senescence. Lines selected for increased longevity have often been shown to perform as well as or superior to control lines in life history, stress resistance and behavioural traits when tested in the laboratory. Functional senescence in longevity selected lines has also been shown to occur at a slower rate. However, it is known that performance in a controlled laboratory setting is not necessarily representative of performance in nature. In this study the effect of ageing, environmental temperature and longevity selection on performance in the field was tested. Flies from longevity selected and control lines of different ages (2, 5, 10 and 15 days) were released in an environment free of natural food sources. Control flies were tested at low, intermediate and high temperatures, while longevity selected flies were tested at the intermediate temperature only. The ability of flies to locate and reach a food source was tested. Flies of intermediate age were generally better at locating resources than both younger and older flies, where hot and cold environments accelerate the senescent decline in performance. Control lines were better able to locate a resource compared to longevity selected lines of the same age, suggesting that longevity comes at a cost in early life field fitness, supporting the antagonistic pleiotropy theory of ageing. 相似文献
83.
Birte Nygaard L. HEGEDÜS M. GERVIL H. HJALGRIM B. M. HANSEN P. S
E-JENSEN J. M. HANSEN 《Journal of internal medicine》1995,238(6):491-497
Abstract. Objectives . To investigate the long-term effect of radioactive iodine (131I) on thyroid function and size in patients with Graves' disease. Setting . Out-patient clinic in Herlev Hospital. Subjects . One hundred and seventeen consecutive patients (104 women) with Graves' disease selected for 131I treatment and followed for a minimum of 12 months (range 1–10 years, median 5 years). Interventions . 131I dose was calculated based on thyroid volume and 24-h 131I uptake. Main outcome measures . Standard thyroid function variables and ultrasonically determined thyroid volume before treatment as well as 0.75, 1.5, 3, 6 and 12 months after treatment, and then once a year were investigated. Results . Seventy-eight patients were cured by one 131I dose and 30 by two doses, while the remaining nine patients received additional doses (range one to five doses, median one dose). Within one year, 25% developed hypothyroidism, and hereafter, hypothyroidism developed at a constant rate of 3% per year independent of antithyroid pretreatment. The cumulative 10-year risk of hypothyroidism was 60%. Initial median thyroid volume was 33 mL (range 9–106 mL). At 12 months after the last 131I dose, median thyroid volume was reduced to 14 mL (range 6–36 mL) (P < 0.00001). The median reduction being 58% (range 0–80%,), hereafter no further reduction occurred. A significant reduction in thyroid volume was also noted in patients needing subsequent 131I doses and in those developing hypothyroidism within the first year. Conclusions . 131I normalizes thyroid volume in patients with Graves' disease. Hypothyroidism seems an inevitable end result of this treatment. The present study suggests that it will be impossible to modify 131I therapy in a way to achieve both early control of hyperthyroidism and a low incidence of hypothyroidism. 相似文献
84.
Karen Petra Weigert Linda Marie Nygaard Finn Bjarke Christensen Ebbe Stender Hansen Cody Bünger 《European spine journal》2006,15(7):1108-1117
A retrospectively designed long-term follow-up study of adolescent idiopathic scoliosis (AIS) patients who had completed treatment, of at least 2 years, by means of brace, surgery, or both brace and surgery. This study is to assess the outcome after treatment for AIS by means of the Scoliosis Research Society Outcome Instrument 24 (SRS 24). One hundred and eighteen AIS patients (99 females and 19 males), treated at the Aarhus University Hospital from January 1, 1987 to December 31, 1997, were investigated with at least 2 years follow-up at the time of receiving a posted self-administered questionnaire. Forty-four patients were treated with Boston brace (B) only, 41 patients had surgery (S), and 33 patients were treated both with brace and surgery (BS). The Cobb angles of the three treatment groups did not differ significantly after completed treatment. The outcome in terms of the total SRS 24 score was not significantly different among the three groups. B patients had a significantly better general (not treatment related) self-image and higher general activity level than the total group of surgically treated patients, while surgically treated patients scored significantly better in post-treatment self-image and satisfaction. Comparing B with BS we found a significantly higher general activity level in B patients, while the BS group had significantly higher satisfaction. There were no significant differences between BS and S patients in any of the domain scores. All treatment groups scored “fair or better” in all domain scores of the SRS 24 questionnaire, except in post-treatment function, where all groups scored worse than “fair”. Improvement of appearance by means of surgical correction increases mean scores for post-treatment self-image and post-treatment satisfaction. Double-treatment by brace and surgery does not appear to jeopardize a good final outcome. 相似文献
85.
Barry J. Snow Torbjoern G. Nygaard Hirohide Takahashi Donald B. Calne 《Annals of neurology》1993,34(5):733-738
There are two major syndromes presenting in the early decades of life with dystonia and parkinsonism: dopa-responsive dystonia (DRD) and early-onset idiopathic parkinsonism (EOIP). DRD presents predominantly in childhood with prominent dystonia and lesser degrees of parkinsonism. EOIP presents before age 40 with parkinsonism (often with associated dystonia). Both disorders are exquisitely sensitive to levodopa, although the long-term prognosis in each appears to be different. Some have suggested, however, that DRD is a form of EOIP. We performed positron emission tomography with 6-fluorodopa in 10 patients with DRD and 18 patients with EOIP to study the integrity of their nigrostriatal dopaminergic systems. In DRD, we found normal striatal FD uptake. In contrast, patients with EOIP had reduced striatal FD uptake. We conclude that the pathophysiologies of DRD and EOIP are distinct. Although both disorders presumably represent a deficiency of striatal dopamine, the results suggest that in DRD dopa uptake, decarboxylation, and storage mechanisms are intact. This may explain the sustained response of DRD to low doses of levodopa. 6-Fluorodopa positron emission tomography distinguishes DRD from EOIP. 相似文献
86.
L T Sirls J E Foote J M Kaufman D J Lightner J L Miller W G Moseley I E Nygaard C P Steidle 《International urogynecology journal》2002,13(2):88-95; discussion 95
A 5-year ongoing, controlled multicenter study enrolled 150 women. Outcome measures included pad weight tests (PWT), voiding diary (VD), quality of life (QOL) and satisfaction questionnaires. Outcome measures during the baseline period were compared to evaluations during follow-up. Concurrent evaluations with and without device use were also performed. Safety evaluations included urinalysis and culture, leak-point pressure (LPP) and cystoscopy. Adverse events (AE) were recorded throughout the study. One to 2 years of follow-up were collected on all study participants (mean 15 months). Statistically significant reductions in overall daily incontinence episodes (P<0.001) and PWT urine loss (P<0.001) were observed with the device at all follow-up intervals, and 93% of women had a negative PWT at 12 months. Women were satisfied with ease of use of the device, comfort and dryness, and significant improvements in QOL were observed (P<0.001). Subgroup analysis revealed that the insert was effective, despite the presence of urgency, low LPP, failed surgery and advanced age. AE included symptomatic urinary tract infection in 31.3%, mild trauma with insertion in 6.7%, hematuria in 3.3%, and migration in 1.3% of women. The results of PWT and VD demonstrated device efficacy. Women were satisfied and significant improvements in QOL were observed. AE were transient and required minimal or no treatment. The urethral insert should be considered as an option for the management of SUI. 相似文献
87.
Anton Brigger Svein Kolmannskog Randi Beck Nicolaysen Finn Wesenberg Randi Nygaard 《Pediatric hematology and oncology》1989,6(2):95-103
Nineteen children treated for Wilms' tumor (thirteen cases) or Hodgkin's disease (six cases) with cytostatic agents and/or radiotherapy were studied cytogenetically on lymphocytes cultivated from blood samples drawn after at least 1 year of complete remission after end of therapy. A reference group of children was matched for age, sex, and residence. The frequencies of sister chromatid exchange (5.4 versus 5.6 SCE/cell), and chromosome damage type gaps (6.6 versus 7.1%) and breaks (1.9 versus 1.9%) were not different in the two groups, but exchange type aberrations were more frequent in the patients (0.9 versus 0.06%). Fifty karyotypes were analyzed in all but two cases of Hodgkin 's disease. The overall frequency of stable (3.1 versus 3.8%) and unstable (1.7 versus 1.4%) structural chromosome changes such as translocations, deletions, chromatid exchanges, and dicentrics were not different in the patient and the control groups. If the chromosome data reflect a general cancer risk, this risk cannot be considerably higher among the cancer-treated children. 相似文献
88.
Among 62 patients with progressive supranuclear palsy (PSP) seen over a 9-year period, we encountered seven who had seizure phenomena. We suggest that PSP patients have seizures more frequently than has been appreciated. 相似文献
89.
H A Nygaard 《Scandinavian journal of primary health care》1988,6(1):33-37
Forty-six patients with senile dementia and their primary caregivers were studied. The strain score of the caregiver and the mental and behavioural deviation of the patients were estimated. Memory problems, listlessness, apathetic, critical and demanding behaviour and urinary incontinence were the most disturbing features of the patients. Eighty-five percent of the caregivers felt despair and anger and 75% complained of chronic fatigue. There was a statistical significant correlation between caregivers strain on one hand, and duration of symptoms, degree of dementia and deviation of behaviour on the other hand. Elderly women caring for their husbands and daughters caring for their parents were especially at risk. Future services must concentrate on maintaining the ability of caregivers to proceed the caring task. 相似文献
90.
The most frequently encountered hand disorders in pregnancy are carpal tunnel syndrome and de Quervain's tenosynovitis. Conservative therapy should be initiated to minimize patient discomfort. Appropriate splinting is the cornerstone of treatment in pregnant women. Surgery is usually not indicated in this patient population. 相似文献