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81.
Reciprocal inhibition of the H-reflex in the forearm flexor muscles was studied in 11 patients with essential tremor and in 10 normal controls. Whereas patients and controls had a similar first, disynaptic phase of reciprocal inhibition, patients had a significantly reduced second phase. Patients with more severe functional impairment had more pronounced abnormalities of reciprocal inhibition. Abnormalities of reciprocal inhibition may play a role in the pathophysiology of essential tremor and probably arise from defective suprasegmental control. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21:796–799, 1998.  相似文献   
82.
Objective: Globally, depression is one of the most prevalent and burdensome conditions in older adults. However, there are few population-based studies of depression in older adults in developing countries. In this paper, we examine the prevalence of depressive symptoms and explore possible contributory risk factors in older adults living in Nepal.

Methods: A cross-sectional study was conducted in two semi-urban communities in Kathmandu, Nepal. Depression was assessed using the 15-item Geriatric Depression Scale in 303 participants, aged 60 years and over. Multivariate logistic regression was then used to assess associations between potential risk factors and depression.

Results: More than half of the participants (n = 175, 60.6%) had significant depressive symptomatology, with 27.7% having scores suggesting mild depression. Illiteracy (aOR = 2.01, 95% CI: 1.08–3.75), physical immobility (aOR = 5.62, 95% CI: 1.76–17.99), the presence of physical health problems (aOR = 1.97, 95% CI: 1.03–3.77), not having any time spent with family members (aOR = 3.55, 95% CI: 1.29–9.76) and not being considered in family decision-making (aOR = 4.02, 95% CI: 2.01–8.04) were significantly associated with depression in older adults.

Conclusion: The prevalence of depression was significant in older adults. There are clear associations of depression with demographic, social support and physical well-being factors in this population. Strategies that increase awareness in the community along with the health and social care interventions are needed to address the likely drivers of depression in older adults.  相似文献   

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To assess the usefulness of vestibular testing in patients with acoustic neuroma, considering two main aspects: to compare diagnostic sensitivity of the current vestibular tests, especially considering ocular vestibular evoked myogenic potentials (OVEMPs) and to identify pre-operative localization of the tumor (inferior vestibular nerve vs. superior vestibular nerve) only with the help of vestibular electrophysiological data. Twenty-six patients with unilateral acoustic neuroma (mainly intracanalicular type) were studied with a full audio-vestibular test battery (pure tone and speech audiometry, caloric bithermal test, vibration-induced nystagmus test (VIN), cervical and OVEMPs). 18 patients (69 %) showed abnormal caloric responses. 12 patients (46.2 %) showed a pattern of VIN test suggestive of vestibular asymmetry. 16 patients (61.5 %) showed abnormal OVEMPs (12 only to AC, 4 both to AC and BC). 10 patients (38.5 %) showed abnormal cervical vestibular evoked myogenic potentials (5 both to AC and BC, 5 only to AC). In one case, results of vestibular evoked potentials and caloric test were confirmed by intra-operative and post-operative findings. Results of electrophysiological tests in AN patients could be helpful for planning the proper surgical approach, considering that sensitivity of every exam is quite low in intracanalicular lesion; clinical data allow a better interpretation of vestibular evoked myogenic potentials.  相似文献   
86.
A study regarding patients with primary and previously untreated advanced histologically proven squamous cell carcinoma of the head and neck was performed to compare two treatment modalities: neck dissection followed by chemoradiotherapy (Group I) versus chemoradiotherapy alone (Group II). Fifty-four patients were randomly chosen to receive Group I or II treatment. Our results demonstrate that Group I treatment has a higher and statistically significant disease-specific survival rate. We suggest that an association of neck dissection plus chemoradiotherapy can be useful in the event of unresectable advanced carcinomas.  相似文献   
87.

Objective

We investigated cochlear function in a group of patients affected by vestibular schwannoma (VS), by means of recording distortion-product otoacoustic emissions (DPOAEs).

Methods

Between January 1996 and January 2007, we observed 183 patients affected by unilateral VS. DPOAEs, compared to the corresponding hearing thresholds, were subjectively classified into three categories: “compatible” with hearing function, “cochlear” and “retro-cochlear”. We also related the responses to some clinical variables (tumor size, intracanalicular tumor and radiologic appearance of the internal auditory canal). Statistical analysis was performed.

Results

In 137 cases (74.9%), DPOAEs were as expected based on audiometry responses, while in 11 patients (6%) a “cochlear” DP-gram was recorded and in 35 patients (19.1%) DPOAEs evidenced a “retro-cochlear” pattern. In eight cases we detected acoustic responses despite a profound hearing loss. No statistically significant data merged from the comparison between “cochlear” and “retro-cochlear” responses and the clinical variables.

Conclusion

Our results confirm that sensorineural hearing loss due to VS can be of sensory and/or neural origin. DPOAEs still remain just a complementary auditory test; nevertheless, in case of severe or profound unilateral hearing loss, recorded acoustic responses may be suspicious for the presence of a vestibular schwannoma.  相似文献   
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89.

Introduction

Mammographic density is known to be a strong risk factor for breast cancer. A particularly strong association with risk has been observed when density is measured using interactive threshold software. This, however, is a labour-intensive process for large-scale studies.

Methods

Our aim was to determine the performance of visually assessed percent breast density as an indicator of breast cancer risk. We compared the effect on risk of density as measured with the mediolateral oblique view only versus that estimated as the average density from the mediolateral oblique view and the craniocaudal view. Density was assessed using a visual analogue scale in 10,048 screening mammograms, including 311 breast cancer cases diagnosed at that screening episode or within the following 6 years.

Results

Where only the mediolateral oblique view was available, there was a modest effect of breast density on risk with an odds ratio for the 76% to 100% density relative to 0% to 25% of 1.51 (95% confidence interval 0.71 to 3.18). When two views were available, there was a considerably stronger association, with the corresponding odds ratio being 6.77 (95% confidence interval 2.75 to 16.67).

Conclusion

This indicates that a substantial amount of information on risk from percentage breast density is contained in the second view. It also suggests that visually assessed breast density has predictive potential for breast cancer risk comparable to that of density measured using the interactive threshold software when two views are available. This observation needs to be confirmed by studies applying the different measurement methods to the same individuals.  相似文献   
90.

Introduction

The purpose of the present study was to investigate the effect of computer-aided detection (CAD) prompts on reader behaviour in a large sample of breast screening mammograms by analysing the relationship of the presence and size of prompts to the recall decision.

Methods

Local research ethics committee approval was obtained; informed consent was not required. Mammograms were obtained from women attending routine mammography at two breast screening centres in 1996. Films, previously double read, were re-read by a different reader using CAD. The study material included 315 cancer cases comprising all screen-detected cancer cases, all subsequent interval cancers and 861 normal cases randomly selected from 10,267 cases. Ground truth data were used to assess the efficacy of CAD prompting. Associations between prompt attributes and tumour features or reader recall decisions were assessed by chi-squared tests.

Results

There was a highly significant relationship between prompting and a decision to recall for cancer cases and for a random sample of normal cases (P < 0.001). Sixty-four per cent of all cases contained at least one CAD prompt. In cancer cases, larger prompts were more likely to be recalled (P = 0.02) for masses but there was no such association for calcifications (P = 0.9). In a random sample of 861 normal cases, larger prompts were more likely to be recalled (P = 0.02) for both mass and calcification prompts. Significant associations were observed with prompting and breast density (p = 0.009) for cancer cases but not for normal cases (P = 0.05).

Conclusions

For both normal cases and cancer cases, prompted mammograms were more likely to be recalled and the prompt size was also associated with a recall decision.  相似文献   
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