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41.
Genetic contributions to Parkinson's disease   总被引:8,自引:0,他引:8  
Sporadic Parkinson's disease (PD) is a common neurodegenerative disorder, characterized by the loss of midbrain dopamine neurons and Lewy body inclusions. It is thought to result from a complex interaction between multiple predisposing genes and environmental influences, although these interactions are still poorly understood. Several causative genes have been identified in different families. Mutations in two genes [α-synuclein and nuclear receptor-related 1 (Nurr1)] cause the same pathology, and a third locus on chromosome 2 also causes this pathology. Other familial PD mutations have identified genes involved in the ubiquitin–proteasome system [parkin and ubiquitin C-terminal hydroxylase L1 (UCHL1)], although such cases do not produce Lewy bodies. These studies highlight critical cellular proteins and mechanisms for dopamine neuron survival as disrupted in Parkinson's disease. Understanding the genetic variations impacting on dopamine neurons may illuminate other molecular mechanisms involved. Additional candidate genes involved in dopamine cell survival, dopamine synthesis, metabolism and function, energy supply, oxidative stress, and cellular detoxification have been indicated by transgenic animal models and/or screened in human populations with differing results. Genetic variation in genes known to produce different patterns and types of neurodegeneration that may impact on the function of dopamine neurons are also reviewed. These studies suggest that environment and genetic background are likely to have a significant influence on susceptibility to Parkinson's disease. The identification of multiple genes predisposing to Parkinson's disease will assist in determining the cellular pathway/s leading to the neurodegeneration observed in this disease.  相似文献   
42.
A methaemoglobin former, 4-aminopropiophenone (p-aminopropiophenone, PAPP), which is active only after metabolic activation in vivo, exhibits a sex difference in male Beagle dogs and bitches. Bitches produced more methaemoglobin for a given dose of PAPP than male dogs. The probable reason for this difference was a lower rate of N-hydroxylation in male dogs.  相似文献   
43.
Four women presented with symptomatic hypercalcaemia and raised concentrations of serum parathyroid hormone (PTH). In each case, serum calcium returned spontaneously to normal. In two patients serum PTH also fell to the normal range and biochemical relapse has not occurred despite prolonged follow-up. In the others, serum PTH remained elevated and subsequent symptomatic hypercalcaemia necessitated parathyroidectomy. In the first two cases, autoparathyroidectomy is the most likely explanation; the initial fall in serum calcium in the other two patients is unexplained. Large fluctuations in serum calcium may occur in some patients with hyperparathyroidism and prolonged and careful observation is required when this occurs.  相似文献   
44.
Walking after stroke. Measurement and recovery over the first 3 months   总被引:4,自引:0,他引:4  
Sixty surviving patients had their walking ability and speed assessed regularly over the first 3 months after an acute stroke. Sixty-four matched controls were studied to allow categorisation of speed as 'slow' or 'normal'. Fourteen patients never had any significant loss of walking speed; fifteen patients never recovered the ability to walk and one patient remained dependent upon verbal support. Of the 30 showing significant recovery, only 10 regained normal speed, and 8 remained dependent upon a physical aid at 3 months. Plotting individual recovery curves of walking speed over time showed the wide range of change which may be expected. It is argued that timing of gait over 10 metres is a valid reliable measure that is currently underused.  相似文献   
45.
Traditionally, neuropsychological deficits due to Sickle Cell Disease (SCD) have been understudied in adults. We have begun to suspect, however, that symptomatic and asymptomatic Cerebrovascular Events (CVE) may account for an alarming number of deficits in this population. In the current brief review, we critically evaluated the pediatric and adult literatures on the neurocognitive effects of SCD. We highlighted the studies that have been published on this topic and posit that early detection of CVE via neurocognitive testing, neuropsychiatric evaluations, and neuroimaging may significantly reduce adult cognitive and functional morbidities.  相似文献   
46.
Background The aim of the present study was to identify factors associated with the level of psychological distress reported by family carers of children with intellectual disability living in a large urban conurbation. Method Information was collected by postal questionnaire (or interview for family carers who did not have English as their first language) from the family carers of 408 children with intellectual disability (31% of all children within the area administratively identified as having an intellectual disability). Results Results indicated that 47% of primary carers scored above the threshold for psychological distress on the GHQ and that scoring above the threshold was strongly related to the emotional and behavioural needs of the index child and South‐Asian ethnicity and moderately associated with the severity of the child's delay in communication. Conclusions The rates of psychological distress (47% overall, 70% among South‐Asian carers) were markedly higher than that found in previous studies of carers supporting a child with intellectual disabilities. It is suggested that these elevated rates of psychological distress may be mediated by socio‐economic deprivation.  相似文献   
47.
48.
Chorioretinal neovascular membranes are a recognised but rare cause of late visual loss in eyes suffering contusional injuries. A series of eight cases is presented all with indirect choroidal ruptures involving the perifoveal region. Two main patterns of 'at risk' rupture were noted: a temporally situated rupture passing almost directly through the fovea, and a rupture which curves inferior or superior to the optic disc stopping just short of the fovea. In six of eight cases there was only a partial thickness rupture of the choroid. These neovascular membranes may present at any time after the original injury, either early (within six months of the injury), which could be related to persistence of the normal reparative neovascular response, or late (at least one year after the injury), which are more likely to have resulted from a secondary breakdown of the outer blood-retina barrier.  相似文献   
49.
A case of benign symmetrical lipomatosis (Madelung-Launois-Bensaude syndrome) is described. The characteristic clinical features and the association with chronic alcoholism are reported.  相似文献   
50.
Say yes to life: a pilot study.   总被引:1,自引:1,他引:0       下载免费PDF全文
In an attempt to assess whether there are any characteristics which a majority of ordinary people regard as life-affirming or life-denying, a questionnaire was given to a pilot group of 167 respondents, representing three different age and social categories. Five life-affirming and five life-denying characteristics were mentioned by more than 10% of respondents. Of the former, Drive, Sociability, Happiness and Optimism were endorsed by 15-20%. Of the latter, Unsociability and Poor Coping were mentioned by 22%, making them distinctly more frequent than the following categories of Pessimism, Lack of Drive and Unhappiness (11-14%). It is suggested that a number of these subjectively determined characteristics, which the general public perceive as being life-affirming or denying, do indeed influence physical or mental health, illness or illness behaviour. It may therefore be of value to utilize this set of public perceptions in future programmes of health education.  相似文献   
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