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1.
《Health & place》2022
An accumulating body of evidence has associated exposure to greenspace with improved birth outcomes, including higher birth weight and lower risk of low birth weight; however, evidence on such association with in-utero fetal growth is scarce. We explored the influence of maternal exposure to residential greenspace and fetal growth in four INMA (Infancia y Medio Ambiente) Spanish birth cohorts (2003–2008), with 2,465 participants. Residential greenspace was characterised by the Normalised Difference Vegetation Index (NDVI) average across 100 m, 300 m, and 500 m buffers around the residence. Repeated ultrasound measurements of the abdominal circumference (AC), biparietal diameter (BPD), femur length (FL), and estimated fetal weight (EFW) were used. We created customised-generalised least squares models to evaluate associations of residential greenspace exposure on each fetal growth parameter, controlled for the relevant confounders. There were associations between the 500 m buffer and BPD, FL, and AC. We also found associations in the 300 m buffer and FL and AC. The associations in the 100 m buffer were null. Estimates were higher among participants with lower socioeconomic status. Mediation analyses found that air pollution might explain 15–37% of our associations. Mediation by physical activity was not observed. Greenspace exposure may be beneficial for fetal growth. 相似文献
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ObjectiveTo determine various morphometric parameters like transverse and sagittal pedicle width; interpedicular distance; antero-posterior and transverse canal diameter and canal surface area at thoracolumbar junction (T11, T12, L1, L2) in central Indian population and compare results with similar studies available in literature.Material and methodsA prospective, computerized tomography scan based morphometric analysis of thoracolumbar junction was conducted at medical college and tertiary care centre in central India. All asymptomatic cases more than 18 years age with normal lateral radiograph and CT scan of thoracolumbar junction and free from any spinal pathology or trauma were included in the study. Parameters measured were transverse and sagittal pedicle width; interpedicular distance; antero-posterior and transverse canal diameter and canal surface area at thoracolumbar junction (T11, T12, L1, L2).ResultsMean transverse pedicle width was maximum at T11 and minimum at L1 in both males and females, whereas sagittal width was maximum at T11 and minimum at L2 in both the groups. Interpedicular distance was largest at L1 in both the groups. All the measurements were significantly different (P < 0.05) in males and females. Mean antero-posterior and transverse diameter was maximum at T12 and L2 respectively in both male and female study population. Canal surface area was maximum at L1 among males (230.10 mm2) as well as females (209.02 mm2).ConclusionThere is significant variation in morphometric parameters of thoracolumbar junction in different races and population. Thorough knowledge of morphometry of a particular population is essential for dealing with pathology or trauma of thoracolumbar junction. 相似文献
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Functional data analysis, which analyzes data that can be represented by curves or images, has many potential applications in clinical trials. Motivated by a real example, this study constructs a functional mixed effects model for analyzing a clinical outcome that is observed continuously over a long period of time. A penalized spline (P-spline)-based method is applied to obtain the estimators of the mean function and the time-varying coefficients. Simulation studies are conducted to investigate the consistency, efficiency, and robustness of the method. To illustrate the use of the method, a real data analysis is performed and produces interpretable results. 相似文献
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Periodontal tissue reactions to orthodontic extrusion 总被引:2,自引:0,他引:2
T. Berglundh C. P. Marinello J. Lindhe B. Thilander B. Liljenberg 《Journal of clinical periodontology》1991,18(5):330-336
Orthodontic tooth extrusion is used at crown lengthening procedures or in conjunction with periodontal therapy aimed at eliminating or reducing angular bone defects. A technique for orthodontic extrusion combined with resection of the supracrestal attachment fibers (fiberotomy) was recently proposed as an adjunct to certain restorative procedures. The aim of the present investigation was to analyze reactions of the periodontal tissues to orthodontic extrusion when combined with fiberotomy. In 5 beagle dogs, the mesial roots of the 2nd, 3rd and 4th hemisected mandibular premolar were used as target roots while the distal roots served as reference units. After a baseline examination, an orthodontic extrusion device (stent) was installed and reactivated at 2-week intervals during an 8-week period of active tooth movement. Immediately following the installation of the stent and once every 2nd week, the target roots were exposed to fiberotomy. After the active period, the teeth were retained in their new position for a period of 8 weeks. Clinical, radiographical and histological measurements were performed. The results from the investigation demonstrated that orthodontic extrusion combined with supracrestal fiberotomy resulted in a coronal displacement of the tooth and was associated with pronounced recession of the gingival margin and extensive loss of connective tissue attachment. The degree of gingival recession and the amount of loss of connective tissue attachment were, however, less extensive than the amount of tooth extrusion. Thus, repeated fiberotomy obviously failed to entirely prevent coronal migration of the attachment apparatus. It was also observed that undesired attachment loss had occurred at the reference roots. 相似文献
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Three commercial agar impression materials, two for clinical uses and one for dental laboratory, were examined for their thermal properties by differential thermogravimetric (DTG) thermal analyses and viscosity measurements. On DTG profiles, an endothermic peak along with weight loss at around 100 degrees C was observed on all three agar impression materials as a result of water evaporation. Two clinical agar impression materials were more susceptible to this trend than the remaining one dental laboratory agar impression material. The viscosity of three agar impression materials could be expressed in the exponential function of temperature. Viscosity at 46 degrees C of one dental laboratory agar impression material far exceeded those of two clinical agar impression materials. Monitoring the viscosity could facilitate the detailed analysis of setting process of agar impression materials upon cooling, and might be useful for future development of agar-based dental impression materials. 相似文献
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OBJECTIVES: The objective of this study was to develop and test the feasibility and validity of a willingness to pay (WTP) tool in a dental setting. METHODS: A questionnaire measured individuals' preferences among alternative treatments for periodontal disease and the maximum they would be willing to pay for their treatment of choice in terms of dental insurance premiums. The questionnaire provides detailed information, in probabilistic terms, of the risks and benefits of treatment choices for moderate to advanced adult periodontitis. It was pilot tested on 23 periodontal patients and 18 dental school faculty and staff. RESULTS: The majority (92.6%) felt the questionnaire was an accurate representation of treatments and outcomes, establishing face and content validity. In terms of construct validity, four hypotheses were tested: (1) manipulation of the outcomes of the preferred treatment led to a predictable shift in preferences for 38 subjects (92.7%); (2) although periodontal patients were not more likely to choose periodontal surgery than nonpatients (P = .14), those with a history of surgery were more likely to choose surgery again (P = .06); (3) WTP was positively related to income level (P = .05); and (4) subjects were willing to pay more for coverage for themselves than for others. Periodontal surgery was the preferred treatment for moderate to advanced periodontal disease, and was more strongly preferred than other choices (i.e., a higher WTP) for all income groups. The intraclass correlation coefficient for treatment preferences was 0.95 (P < .001) and the kappa for WTP was 0.78 (P < .001). CONCLUSION: This pilot study supports some of the criteria concerning validity of the WTP questionnaire to measure preferences for alternative periodontal therapies. Further testing on larger samples is required to confirm these results. 相似文献
10.
Shunji Yoshida 《Odontology / the Society of the Nippon Dental University》1999,86(4):915-931
Anthropological surveys of the Pukapuka Atoll, the Northern Cook Islands, discovered several intements dated around 1500 B.P,
from which twenty-five interred human remains were retrieved. This study describes several features revealed from analyses
on the skulls of 6 males.
1) | The craniometrical comparison of the skulls with the heads of modern Pukapukan males revealed a feature, that the prehistoric specimens were mesocranic, whereas the modern people showed brachycephalic. |
2) | The craniometrical comparison with prehistoric specimens from other islands in Oceania populations demonstrated that the prehistoric Pukapukan exhibited typical features of prehistoric Polynesians, that they are larger than the specimen from other regions in sagittal frontal arc, sagittal chord, bimaxillary breadth and mandibular ramus breadth. |
3) | The craniometrical comparisons with Japanese specimens in Jomon, Yayoi, Kamakura, Edo and modern periods revealed that prehistoric Pukapukan specimens were larger in sagittal frontal arc, sagittal frontal chord, bimaxillary breadth and mandibular ramus breadth than Japanese ones in any periods. |
4) | The odservation of teeth in excavated Pukapukan skulls revealed that their percent of carious teeth reached 7.4% in average. |
5) | The pricipal coordinate analysis of craniometrical features from thirteen groups including five islands in Polynesia, three islands in Micronesia, and Japanese groups from Jomon, Yayoi, Kamakura, Edo and Modern periods demonstrated that there were no homogeneity between prehistoric Polynesian and Japanese in the Jomon period. |
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