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991.
Objectives

This study aimed to investigate the three-dimensional (3D) mandibular asymmetry in craniofacial microsomia (CFM) and its association with the Pruzansky–Kaban classification system.

Materials and methods

Cone-beam computed tomography images of 48 adult CFM cases were collected. The asymmetry of the mandibular body and ramus was analyzed with 3D landmarks. The mirrored mandibular model was registered on the original model, yielding a color-coded distance map and an average distance (i.e., asymmetry score) to quantify the overall mandibular asymmetry.

Results

The lengths of the mandibular body and ramus were significantly shorter on the affected than the contralateral side (p < 0.001). The ANB (p = 0.009), body and ramal lengths (both p < 0.001), and body and ramal length asymmetry (both p < 0.05) were significantly different between mild (types I/IIA) and severe (types IIB/III) cases. The mandibular asymmetry score correlated with mandibular body length asymmetry (r = 0.296, p = 0.046). CFM mandibles showed high variability in shape asymmetry.

Conclusions

CFM patients showed distinct body and ramal length asymmetries. In severe cases, mandibles were smaller, more retruded, and more asymmetric in length. The mandibular shape asymmetry was highly variable regardless of the Pruzansky–Kaban types, being a determinant in the extent of overall mandibular asymmetry.

Clinical relevance

The 3D morphologic analysis provides better insights into real mandibular asymmetry. Although the Pruzansky–Kaban classification was applied, high individual variability of the mandibular morphology still existed within the types. Therefore, individualized analyses and treatment plans for CFM patients are highly recommended.

  相似文献   
992.
Laboratory-based surveillance of invasive pneumococcal infections in adults in Finland from 1983 to 1992 identified 862 episodes of pneumococcal bacteraemia and 97 episodes of meningitis. The overall incidence of invasive pneumococcal infections was 9.1 per 100,000 for all adults per year, but 27.1, 35.8, and 44.5 per 100,000 in those aged 65 years or over, 75 years or over, and 85 years or over, respectively. Most (99.7%) of the pneumococcal strains were sensitive to penicillin. Ninety-five percent of the strains belonged to serogroups/types present in the 23-valent pneumococcal polysaccharide vaccine. Group/type distribution was different in patients aged 16-64 years compared to those 65 years or over (P < 0.001), in bacteraemia compared to meningitis (P < 0.001), and in the years 1983-7 compared to 1988-92 (P < 0.05).  相似文献   
993.
The purpose of this study was to investigate long-term clinical effectiveness of treating painful cracked teeth with a direct bonded composite resin restoration. The hypothesis tested was that cracked teeth treated with or without cuspal coverage showed the same performance. Forty-one patients attended a dental practice with a painful cracked tooth that was restored with a direct composite resin restoration. Twenty teeth were restored without and 21 with cuspal coverage. After 7 years, 40 teeth could be evaluated. Three teeth without cuspal coverage needed an endodontic treatment, of which 2 failed as a result of fracture. No significant differences were found for tooth or pulp survival. Three more repairable restoration failures were recorded. Mean annual failure rate of restorations without cuspal coverage was 6%; no failures in restorations with cuspal coverage occurred (P = .009). A direct bonded composite resin restoration can be a successful treatment for a cracked tooth.  相似文献   
994.
To treat mixed skin ulcers effectively, it is important to investigate skin microcirculation in greater detail. Therefore, we used laser Doppler perfusion imaging and capillary microscopy for assessing both subpapillary and nutritive microcirculation in four defined regions of the skin in 17 patients with mixed ulcers caused by a combination of peripheral arterial occlusive disease and chronic venous insufficiency. Laser Doppler area flux was significantly higher in the ulcer areas than in the areas without granulation tissue and those in intact skin. The flux in the scars was higher than that in the intact skin or in the ulcer areas without granulation tissue. Capillary density in the intact skin was higher than the densities in nongranulation tissue areas, granulation areas, and scar areas ( p <0.001 for all comparisons). To conclude, the ulcer areas without granulation tissue did not show a healing tendency due to poor subpapillary and nutritive perfusion; the granulation tissue exhibited high subpapillary perfusion as a sign of healing. In the scars, sufficient blood supply could be detected in both layers as a sign of an almost complete healing process. Blood supply in the intact skin is, however, already affected by distorted microcirculation in the ulcers.  相似文献   
995.
996.
Aim: To established population norms for pedometer determined step counts in older Australians. Methods: A representative sample of 684 participants over the age of 55 years wore a pedometer for a week in Newcastle, Australia. Results: Response rate was 32%. Median daily step count was 8605 in those aged 55–59 years declining to 3778 in those over 80 years old. The proportion who reached 8000 steps per day was 62% in those 55–59 years and 12% in those over 80 years. Daily step counts were highest on Thursdays and Fridays and least on Sundays. Weekend days had on average 620 less steps than weekdays. After adjusting for age, there was a negative association of step count with body mass index >30, and with a history of arthritis but no significant association with other demographic variables. Conclusion: Pedometry is feasible in an elderly sample, and research involving pedometers must take days of the week into account.  相似文献   
997.

Objective

Our aim was to assess the effectiveness and reliability of spatiotemporal signal space separation (tSSS) and movement correction (MC) in magnetoencephalography (MEG) recordings disturbed by head movements and magnetized material on the head.

Methods

We recorded MEG from 20 healthy adults in stationary (reference) head position and during controlled head movements. Nearby magnetic interference sources were simulated by attaching magnetized particles on the subject’s head. Auditory and somatosensory stimuli were presented. MC, tSSS and averaging were performed to obtain auditory (AEF) and somatosensory (SEF) evoked fields. Neuronal sources were modeled as equivalent current dipoles. MC was also validated by reconstructing signals generated by current dipoles in a phantom.

Results

After MC, the AEF and SEF responses recorded during intermittent head movements were similar in amplitude to the reference recordings and differed by 5–7 mm in source location. The tSSS method removed artifacts due to the attached magnetized particles but did not affect the reference data.

Conclusions

The methods are able to reliably recover MEG responses contaminated by movements and magnetic artifacts on the head.

Significance

The combination of tSSS and MC methods is especially useful in clinical measurements, where movements and magnetic disturbances are commonly present.  相似文献   
998.
The brains of Alzheimer's disease patients show an increased number of senile plaques compared with normal patients. The major component of the plaques is the β-amyloid peptide, a cleavage product of the amyloid precursor protein (APP). Although the processing of APP has been well-described, the physiological functions of APP and its cleavage products remain unclear. This article reviews the multifunctional roles of an APP orthologue, the C. elegans APL-1. Understanding the function of APL-1 may provide insights into the functions and signaling pathways of human APP. In addition, the physiological effects of introducing human β-amyloid peptide into C. elegans are also reviewed. The C. elegans system provides a powerful genetic model to identify genes regulating the molecular mechanisms underlying intracellular β-amyloid peptide accumulation.  相似文献   
999.
Heart rate variability (HRV) is a measure of autonomic influences on heart rate that has frequently been used as a transsituationally consistent biomarker for cardiovascular health and emotional or cognitive functions. The psychometric properties of HRV however remain unclear. In the present study, we examined the reliability and temporal stability of parasympathetic HRV measures and estimated the portion of variance explained by transsituationally consistent trait variance and by effects of the situation and person-situation interaction with structural equation modeling. The results show good reliability of indices reflecting central parasympathetic control over heart rate and that about 40% of the variance of a single HRV measurement can be explained by effects of the situation and person-situation interaction. An aggregation across at least two measurements may be recommended when using HRV as a transsituationally consistent biomarker or trait.  相似文献   
1000.
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