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21.
A cross-sectional study of health complaints among 79 data entry operators using video display terminals 总被引:1,自引:0,他引:1
This paper reports on the findings of a cross-sectional study of 79 data entry clerks employed by an Ontario-based organization in five separate offices. The study was conducted to identify factors associated with physical complaints experienced by these office workers. A large percentage of the data entry clerks reported chronic physical complaints (eyestrain, musculo-skeletal pains, headache) as well as emotional or mental stress which they felt were associated with their occupation. Poorly designed overhead lighting systems in all offices contributed to both eyestrain and headache. Duration of employment as a data entry operator within the organization was not associated with stress or physical health complaints. The presence of an adjustable workstation did not in itself guarantee any protection from these conditions. Highly significant associations between occupational stress levels and some physical complaints were observed. The presence of these associations indicated that the management of both physical and stress complaints within these office environments should be tackled simultaneously. 相似文献
22.
The contribution of the central nervous system to tremor pathogenesis is unclear. Poor side-to-side coherence in physiological, essential, and parkinsonian tremors suggests distinct bilateral generators. By contrast, significant bilateral coherence demonstrated in orthostatic tremor and in enhanced physiological tremor (EPT) in patients with persistent mirror movements favours single or closely linked bilateral oscillators. We describe three patients (aged 21-37 years) who developed unusual bilateral postural and kinetic tremors at 6-13 Hz resembling EPT. The tremor involved all limbs, and in two cases the face or jaw, in the absence of other significant neurological features. Significant side-to-side coherence was demonstrated in each case using cross-correlation of electromyographic recordings from homologous muscle pairs. We postulate that these unusual tremors originate from a single brainstem source or from bilateral oscillators closely linked at or below this level. 相似文献
23.
Christoph Scherfler MD Johannes Schwarz MD PhD Angelo Antonini MD PhD Donald Grosset MD Francesc Valldeoriola MD PhD Kenneth Marek MD Wolfgang Oertel MD Eduardo Tolosa MD PhD Andrew J. Lees MD Werner Poewe MD 《Movement disorders》2007,22(9):1229-1238
The diagnosis of idiopathic Parkinson's disease (PD) can be achieved with high degrees of accuracy in cases with full expression of classical clinical features. However, diagnostic uncertainty remains in early disease with subtle or ambiguous signs. Functional imaging has been suggested to increase the diagnostic yield in parkinsonian syndromes with uncertain clinical classification. Loss of striatal dopamine nerve terminal function, a hallmark of neurodegenerative Parkinsonism, is strongly related to decreases of dopamine transporter (DAT) density, which can be measured by single photon emission computed tomography (SPECT). The use of DAT‐SPECT facilitates the differential diagnosis in patients with isolated tremor symptoms not fulfilling PD or essential tremor criteria, drug‐induced, psychogenic and vascular Parkinsonism as well as dementia when associated with Parkinsonism. This review addresses the value of DAT‐SPECT in early differential diagnosis, and its potential as a screening tool for subjects at risk of developing PD as well as issues around the assessment of disease progression. © 2007 Movement Disorder Society 相似文献
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Off-period belching due to a reversible disturbance of oesophageal motility in Parkinson's disease and its treatment with apomorphine 总被引:1,自引:0,他引:1
Two L-dopa-treated patients with Parkinson's disease who developed distressing belching during "off" periods are reported. In each case, contrast cine radiography revealed disturbed oesophageal motility which disappeared after injection of the dopamine receptor agonist apomorphine. It is suggested that central dopaminergic abnormalities may be important in the aetiology of "off period belching." 相似文献
26.
R E Lees B R Laundry 《Canadian journal of public health. Revue canadienne de santé publique》1989,80(6):423-426
Understanding the causes of industrial accidents will be limited if only incidents which produce injury are studied. We examined the records of 514 Potential Major Injury events over a 20-year period in one plant. Injuries were sustained in 228 (44%) of them; 286 (56%) could be classed as "near-miss" incidents and were not associated with injury. Human error accounted for most incidents and was a more important factor among those with less experience on the job. Overall, third party injuries resulted from only 5% of incidents but from 11% of those caused by human error. Although the number of human error incidents fell by 19.5% between the first and second 10-year periods, their relative importance increased as the company managed to reduce incidents of equipment and structural failure even more. We suggest that the term Critical Incident is the most fitting for the first of a series of events in the spectrum of accidents. 相似文献
27.
Regulation of the immune response: II. Further studies on differences in ability of F(ab′)2 and 7S antibodies to inhibit an antibody response
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The ability of F(ab′)2 antibody preparations to suppress an immune response is much less than that of intact 7S antibody. The activity possessed by F(ab′)2 preparations withstood repurification procedures, hence contamination with intact 7S antibody is unlikely. Daily or thrice daily injections of antibody did not make equal the suppressive activities of F(ab′)2 and intact antibody, indicating that rapid excretion of F(ab′)2 antibody is not the sole factor involved in the difference in immunosuppressive potency between intact 7S and F(ab′)2 antibody. Some possibilities for distinct differences in the mechanism of the immuno-suppressive action of F(ab′)2 and 7S antibodies are raised and discussed. 相似文献
28.
Structure-function relationships for human antibodies to pneumococcal capsular polysaccharide from transgenic mice with human immunoglobulin Loci
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To investigate the influence of antibody structure and specificity on antibody efficacy against Streptococcus pneumoniae, human monospecific antibodies (MAbs) to serotype 3 pneumococcal capsular polysaccharide (PPS-3) were generated from transgenic mice reconstituted with human immunoglobulin loci (XenoMouse mice) vaccinated with a PPS-3-tetanus toxoid conjugate and their molecular genetic structures, epitope specificities, and protective efficacies in normal and complement-deficient mice were determined. Nucleic acid sequence analysis of three MAbs (A7, 1A2, and 7C5) revealed that they use two different V(H)3 genes (A7 and 1A2 both use V3-15) and three different V(kappa) gene segments. The MAbs were found to have similar affinities for PPS-3 but different epitope specificities and CDR3 regions. Both A7 and 7C5 had a lysine at the V(H)-D junction, whereas 1A2 had a threonine. Challenge experiments with serotype 3 S. pneumoniae in BALB/c mice revealed that both 10- and 1- micro g doses of A7 and 7C5 were protective, while only a 10- micro g dose of 1A2 was protective. Both A7 and 7C5 were also protective in mice lacking either an intact alternative (FB(-/-)) or classical (C4(-/-)) complement pathway, but 1A2 was not protective in either strain. Our data suggest that PPS-3 consists of epitopes that can elicit both highly protective and less protective antibodies and that the superior efficacies of certain antibodies may be a function of their structures and/or specificities. Further investigation of relationships between structure, specificity, and efficacy for defined MAbs to PPS may identify antibody features that might be useful surrogates for antibody (and vaccine) efficacy. 相似文献
29.
Effects of tibolone on bone quality in ovariectomized monkeys 总被引:1,自引:0,他引:1
OBJECTIVE: The purpose of this report is to examine the effects of two doses of tibolone on bone quality (bone biomarkers, bone density, and bone strength) in ovariectomized cynomolgus monkeys fed high-fat diets. DESIGN: Ovariectomized cynomolgus monkeys were randomized into one of five treatment groups: placebo-treated control, tibolone (0.2 mg/kg/day), tibolone (0.05 mg/kg/day), conjugated equine estrogens (Premarin, 0.042 mg/kg/day), and conjugated equine estrogens plus medroxyprogesterone acetate (0.042 and 0.167 mg/kg/day, respectively). Bone quality was assessed by determining bone strength and density in vertebrae and femora collected after 24 months of treatment. RESULTS: Monkeys treated for 24 months with tibolone had increased bone mineral density in the distal femur and improved biomechanical properties in the midshaft femur compared with placebo-treated ovariectomized monkeys, as did monkeys treated with conjugated equine estrogens with or without medroxyprogesterone acetate. No treatment effects were seen in lumbar vertebra bone density or strength. There was no significant difference between tibolone and estrogen on biomechanical properties of the femur. CONCLUSION: These data show that tibolone is comparable to conjugated equine estrogens with or without medroxyprogesterone acetate in decreasing bone turnover and increasing bone strength in ovariectomized monkeys. 相似文献
30.