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131.
Tooth loss diminishes oral function and quality of life, and national health targets aim to reduce population levels of tooth loss. OBJECTIVES: The purpose of this study was to determine tooth loss incidence and predictors of tooth loss among older adults in South Australia. METHODS: Data were obtained from a cohort study of a stratified random sample of community-dwelling dentate people aged 60+ years. Interviews and oral examinations were conducted among 911 individuals at baseline and among 693 of them (76.1%) 2 years later. Incidence rates and relative risks were calculated for population subgroups and multivariate logistic regression was used to construct risk prediction models. A method was developed to calculate 95% confidence intervals (95% CI) for relative risks (RR) from logistic regression models using a Taylor series approximation. RESULTS: Some 19.5% (95% CI = 15.4-23.6%) of people lost one or more teeth during the 2 years. Men, people with a recent extraction, people who brushed their teeth infrequently, smokers and people born outside Australia had significantly (P < 0.05) greater risk of tooth loss. Baseline clinical predictors of tooth loss included more missing teeth, retained roots, decayed root surfaces, periodontal pockets and periodontal recession. In a multivariate model that controlled for baseline clinical predictors, former smokers (RR = 2.55, 95% CI = 1.48-4.40) and current smokers (RR = 2.06, 95% CI = 0.92-4.62) had similarly elevated risks of tooth loss compared with non-smokers. CONCLUSIONS: The findings from this population suggest that a history of smoking contributes to tooth loss through mechanisms in addition to clinical disease processes alone.  相似文献   
132.
There are many in vivo animal models for studying airway mucus secretion and hypersecretion, each with advantages and disadvantages. Use of a particular test system will depend upon the aspect of secretion to be modelled. Airway hypersecretory diseases exhibit chronic mucus hypersecretion, of which the clinical impact is predominantly in the distal airways. The majority of documented test preparations study acute secretion, invariably using tracheal preparations, but have been invaluable in elucidating the normal physiology of airway mucus secretion. Chronic models of the hypersecretory state in the distal airways have been developed, but are predominantly histologic in nature (for example quantification of increased goblet cell number). There are few investigations of mucus hypersecretion. Examination of the 'antisecretory' potential of pharmaceutical compounds has been investigated predominantly in chronic histologic models with the drug being given 'prophylactically' rather than 'therapeutically'. Refinement of chronic hypersecretory models should lead to elucidation of the connection between airway irritation, inflammation, MUC gene expression, mucous cell hyperplasia/metaplasia, airway hypersecretion and bronchial hypersecretory disease.  相似文献   
133.
Two types of thermomechanical constraint are known to the literature, the first consisting of a relation between the deformation and temperature, the second consisting of a relation between deformation and entropy. The first is known to be unstable in response to small disturbances and the second stable. Insight into these unphysical instabilities is sought by modelling each constraint as the limit of a nearly constrained thermoelastic material. It is found that each deformation-entropy near-constraint is equivalent to a corresponding deformation-temperature near-constraint. But the limit of the deformation-entropy constraint holding exactly is found to correspond to a situation where the limit of the deformation-temperature near-constraint has not been reached. Then this constraint holds only approximately and the need for unphysical instabilities is avoided.  相似文献   
134.
The storing of recorded bits in a perpendicular orientation holds great promise for high linear density recording systems. However, the most common embodiment of perpendicular recording (the probe head/double layer media) has several unresolved issues complicating its integration into commercial disk drives. The major issues include media relaxation, head induced media erasure, resolution limitations due to head-to-underlayer spacing constraints, and extreme sensitivity to stray magnetics fields, which are complex and highly interrelated. It is concluded that the realization of perpendicular recording in commercial disk drives will require new transducer and media designs that solve these problems  相似文献   
135.
136.
Examined publishing practices of the American Psychological Association (APA) in the alcohol and drug area. Although the total number of articles published by APA increased only 7.6% between 1984 and 1990, the number of alcohol and drug articles more than doubled. Despite the disproportionate growth of alcohol and drug articles between 1984 and 1990, only 3.8% of 1,408 APA articles published in 1990 addressed alcohol and drug use issues. An earlier investigation by M. O. Howard and D. A. Howard (1992) reported that 541 articles published in 1984 in 12 alcohol and drug specialty journals received an average of 3.48 citations by the end of 1988. Alcohol and drug articles published by APA in 1984 received more than 4 times as many citations during this period. Also, alcohol and drug articles published by APA received significantly more citations between 1984 and 1988 than those published in specialty journals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
137.
Hereditary motor sensory neuropathies are a heterogeneous group of inherited diseases of the peripheral nerves. In this review the clinical and genetic differences between the sub-groups of this disease will be discussed. Since the discovery of a 1.5 mb duplication on chromosome 17 p11.2-12 in most patients with a hereditary motor sensory neuropathy and a variety of different mutations on chromosomes 1 and X in other patients with a similar disease profile, Dycks' clinical classification needs to be re-evaluated. In this review Dycks' taxonomy of heridihary neuropathies will be compared to a new genetic classification and a relevant diagnostic procedure proposed when a hereditary neuropathy is suspected.  相似文献   
138.
139.
In the design of algorithms for large-scale applications it is essential to consider the problem of minimizing I/O communication. Geographical information systems (GIS) are good examples of such large-scale applications as they frequently handle huge amounts of spatial data. In this paper we develop efficient external-memory algorithms for a number of important problems involving line segments in the plane, including trapezoid decomposition, batched planar point location, triangulation, red--blue line segment intersection reporting, and general line segment intersection reporting. In GIS systems the first three problems are useful for rendering and modeling, and the latter two are frequently used for overlaying maps and extracting information from them.  相似文献   
140.
Polarised attenuated total reflection FTIR spectroscopy has been used for detailed orientation mapping of 2l polyethylene terephthalate bottles subjected to different preform heating times. The results for the bottle with the standard preform heating time reveal significant surface orientation variations along the bottle hoop and length directions, with the inner bottle surface also showing consistently greater chain orientation in the hoop direction than found for the outer surface. Decreasing the preform heating time has less effect on the chain orientation than increasing the heating time, with the latter causing reduced chain orientation in the final bottle. The absorbance of the 1340 cm−1 band provides a quick and reliable indication of these chain orientation trends. In contrast, the extent of benzene ring orientation parallel to the bottle surface showed little variation and remained consistently high at the majority of the surface bottle positions probed.  相似文献   
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