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101.
Reduced Purkinje cell density in Huntington's disease   总被引:2,自引:0,他引:2  
We studied, in a "blind" and quantitative fashion, the density of cerebellar Purkinje cells in 17 adult cases of Huntington's disease (HD), 17 patients with other movement disorders, 17 with schizophrenia, and 23 normal controls. There was a highly significant reduction in Purkinje cell density in HD compared with any of the other three groups. A much smaller difference in neuronal density between patients with other movement disorders and normal controls was barely significant. Eight of the 17 HD patients and only 1 of the other 57 subjects had Purkinje cell density less than 50% of the mean for the normal controls. The low density of Purkinje cells in HD could not be attributed to aging, seizures, or cause of death, nor was it merely a part of a generalized brain atrophy. The loss of large Purkinje cells suggests that the neuronal loss in HD may not be restricted to small and medium-size neurons.  相似文献   
102.
Using a liquid chromatographic assay, we measured serum neuroleptic concentrations in eight middle-aged or elderly female inpatients with tardive dyskinesia (TD) and eight controls. All 16 patients were receiving either thioridazine or mesoridazine at stable doses. TD patients were found to have a significantly higher ratio of serum concentration to daily dose of neuroleptics compared with controls. A 1-year follow-up revealed that this ratio did not change appreciably in those patients who continued to receive neuroleptics. Differences in serum neuroleptic levels were not related to peripheral inflammatory activity as indicated by serum -1-acid glycoprotein concentrations. Of the various thioridazine metabolites, sulforidazine (which is reportedly the most potent in terms of affinity for dopaminergic and -noradrenergic receptors) seemed to be significantly elevated in the serum of TD patients as compared with non-TD patients. Our data suggest a need for further pharmacokinetic investigations to study neuroleptic metabolism in patients with TD.  相似文献   
103.
Twelve elderly women with tardive dyskinesia were matched with 12 patients without dyskinesia. Lymphocyte monoamine oxidase (MAO) activity and plasma prolactin and growth hormone concentrations were determined "blind" in these 12 pairs of patients. Chronic schizophrenic patients with tardive dyskinesia had significantly lower lymphocyte MAO activity as compared to controls. Organic brain syndrome patients with dyskinesia did not differ from controls in the lymphocyte MAO activity. These results with lymphocyte MAO parallel our earlier findings on platelet MAO. No significant differences were found between dyskinesia group and controls in the plasma prolactin and growth hormone concentrations. Possible implications of our findings are discussed.  相似文献   
104.
The locus ceruleus (LC), a pigmented brainstem nucleus rich in noradrenergic neurons, has been proposed to be involved in the pathophysiology of aging and schizophrenia. We undertook a quantitative neuropathological study of the LC in these two conditions. A computing planimeter was employed to count the total number of neurons and measure the volume of the LC, neuronal cross-sectional area, and percent of neuronal area occupied by neuromelanin in the brains of 39 subjects; 13 "normative", 15 leucotomized schizophrenic (most had died in the preneuroleptic era), and 11 leucotomized non-schizophrenic control patients, ranging in age from 11 to 94 years. There was a significant inverse correlation between age and total number of LC neurons, neuronal size, and LC volume, and a significant positive correlation between age and the percentage of neuronal area occupied by neuromelanin. Although schizophrenics did not differ significantly from control groups on any of the parameters of LC morphology, there was a trend for reduced LC volume in schizophrenic brains. Also, the LC of leucotomized patients tended to have increased neuromelanin content and slightly increased cell counts compared to normals, although the importance of this finding is not clear.  相似文献   
105.
Male andropause, male climacteric or viropause is a condition in which men suffer from complex symptomatology due to low androgen level with aging. After the age of 40 years testosterone level starts declining and andropause corresponds to the age at which a pathogenic threshold is reached. This review summarizes the etiology, consequences, screening, diagnosis, monitoring of androgen deficiency in aging male (ADAM). The pros and cons of testosterone replacement therapy (TRT) in elderly male have been discussed. Currently oral, transdermal, transbuccal, intramuscular, and subcutaneous implants are available for clinical use. The choice is made by physicians based on therapeutic indication and patient preferences.  相似文献   
106.
OBJECTIVE: The authors assessed the need for mental health services among older adults in San Diego County, California, by determining what needs were not being addressed by existing services, what services were necessary to address these needs, and how much consensus there was among different stakeholders with respect to the problems and solutions related to service delivery. METHODS: Semistructured interviews were conducted with 23 health care and social service providers and administrators, 16 services consumers and other older adults (55 years of age and older), and 19 caregivers/family members and patient/client advocates. This was followed by four focus groups comprised of 18 providers and administrators, six focus groups comprised of 50 consumers and other older adults, and five focus groups comprised of 39 caregivers (family members and advocates). RESULTS: The unmet needs fell into three categories: mental health services, physical health services, and social services. Two interrelated themes were identified by participants: 1) the need for age-appropriate and culturally appropriate services to overcome barriers to mental health services access, use, and quality; and 2) the interrelations between unmet needs that address prevention as well as treatment of mental illness, including socialization and social support, transportation, housing, and physical health care. Differences in stakeholder assessment of unmet needs were associated with respective roles in delivery and use of mental health services. CONCLUSION: Age-appropriate and culturally appropriate solutions that address both prevention and treatment may represent the best strategies for addressing the challenges of mental illness and are most likely to be endorsed by all three groups of stakeholders.  相似文献   
107.

Background

Angelman syndrome (AS) is a severe neurodevelopmental disorder caused by either disruptions of the gene UBE3A or deletion of chromosome 15 at 15q11-q13, which encompasses UBE3A and several other genes, including GABRB3, GABRA5, GABRG3, encoding gamma-aminobutyric acid type A receptor subunits (β3, α5, γ3). Individuals with deletions are generally more impaired than those with other genotypes, but the underlying pathophysiology remains largely unknown. Here, we used electroencephalography (EEG) to test the hypothesis that genes other than UBE3A located on 15q11-q13 cause differences in pathophysiology between AS genotypes.

Methods

We compared spectral power of clinical EEG recordings from children (1–18 years of age) with a deletion genotype (n = 37) or a nondeletion genotype (n = 21) and typically developing children without Angelman syndrome (n = 48).

Results

We found elevated theta power (peak frequency: 5.3 Hz) and diminished beta power (peak frequency: 23 Hz) in the deletion genotype compared with the nondeletion genotype as well as excess broadband EEG power (1–32 Hz) peaking in the delta frequency range (peak frequency: 2.8 Hz), shared by both genotypes but stronger for the deletion genotype at younger ages.

Conclusions

Our results provide strong evidence for the contribution of non-UBE3A neuronal pathophysiology in deletion AS and suggest that hemizygosity of the GABRB3-GABRA5-GABRG3 gene cluster causes abnormal theta and beta EEG oscillations that may underlie the more severe clinical phenotype. Our work improves the understanding of AS pathophysiology and has direct implications for the development of AS treatments and biomarkers.  相似文献   
108.
109.
在选择测量方法时,考虑测量结果中不确定度中包含的因子或不确定度的计算值是否可以减小不失为一个好的方法。通过不确定度的评定来减小测量不确定度的计算值是改进物理实验方法的有效途径,我们在探索减小测量误差的过程中,可以根据不确定度分量进行有目的的改进,而不必一味追求配备高精度的测量仪器。  相似文献   
110.
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