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排序方式: 共有5173条查询结果,搜索用时 218 毫秒
1.
Ghabriel Mounir Takezawa Kojiro Townsend Grant 《Odontology / the Society of the Nippon Dental University》2019,107(1):1-9
Odontology - This article, for both researchers and clinicians, presents an overview of the lingual nerve and highlights how new insights into human anatomical variability can be gained by... 相似文献
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Amanda H. Anderson Dawei Xie Xue Wang Robin L. Baudier Paula Orlandi Lawrence J. Appel Laura M. Dember Jiang He John W. Kusek James P. Lash Sankar D. Navaneethan Akinlolu Ojo Mahboob Rahman Jason Roy Julia J. Scialla James H. Sondheimer Susan P. Steigerwalt F. Perry Wilson Raymond R. Townsend 《American journal of kidney diseases》2021,77(1):56-73.e1
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Gian Luca Negri Bruno M Grande Alberto Delaidelli Amal El-Naggar Dawn Cochrane Ching C Lau Timothy J Triche Richard A Moore Steven JM Jones Alexandre Montpetit Marco A Marra David Malkin Ryan D Morin Poul H Sorensen 《The Journal of pathology》2019,249(3):319-331
Despite being the most common childhood bone tumor, the genomic characterization of osteosarcoma remains incomplete. In particular, very few osteosarcoma metastases have been sequenced to date, critical to better understand mechanisms of progression and evolution in this tumor. We performed an integrated whole genome and exome sequencing analysis of paired primary and metastatic pediatric osteosarcoma specimens to identify recurrent genomic alterations. Sequencing of 13 osteosarcoma patients including 13 primary, 10 metastatic, and 3 locally recurring tumors revealed a highly heterogeneous mutational landscape, including cases of hypermutation and microsatellite instability positivity, but with virtually no recurrent alterations except for mutations involving the tumor suppressor genes RB1 and TP53. At the germline level, we detected alterations in multiple cancer related genes in the majority of the cohort, including those potentially disrupting DNA damage response pathways. Metastases retained only a minimal number of short variants from their corresponding primary tumors, while copy number alterations showed higher conservation. One recurrently amplified gene, KDR, was highly expressed in advanced cases and associated with poor prognosis. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
6.
Marilyn S. Townsend Mical K. Shilts Dennis M. Styne Christiana Drake Louise Lanoue Lenna Ontai 《Journal of nutrition education and behavior》2018,50(7):705-717
Objective
Demonstrate validity and reliability for an obesity risk assessment tool for young children targeting families' modifiable home environments.Design
Longitudinal design with data collected over 100 weeks.Setting
Head Start and the Special Supplemental Nutrition Program for Women, Infants, and Children.Participants
Parent–child pairs (n?=?133) provided food behavior assessments; 3 child-modified, 24-hour dietary recalls; 3?≥?36-hour activity logs; and measured heights and weights.Main Outcome Measure
Five measures of validity and 5 of reliability.Results
Validity was excellent for the assessment tool, named Healthy Kids, demonstrating an inverse relationship with child body mass index percentile-for-age (P?=?.02). Scales were significantly related to hypothesized variables (P?≤?.05): fruit or vegetable cup equivalents; folate; vitamins A, C, and D; β-carotene; calcium; fiber; sugar; screen, sleep, and physical activity minutes; and parent behaviors. Measures of reliability were acceptable.Conclusions and Implications
Overall, children with higher Healthy Kids scores had a more healthful profile as well as lower body mass index percentiles-for-age 1.5 years later. Healthy Kids has potential for use by nutrition professionals as a screening tool to identify young children most at risk for excess weight gain, as an evaluation to assess intervention impact, and as a counseling tool to tailor intervention efforts. Future research should include validation in other settings and with other populations. 相似文献7.
Hersh EV Giannakopoulos H Levin LM Secreto S Moore PA Peterson C Hutcheson M Bouhajib M Mosenkis A Townsend RR 《Journal of the American Dental Association (1939)》2006,137(11):1562-1571
OBJECTIVES: The authors conducted a randomized, double-blind, two-way crossover clinical trial to compare the pharmacokinetics and cardiovascular effects of 11.9 milliliters of 4 percent articaine hydrochloride (HCl) plus 1:100,000 epinephrine (A100) with those of 11.9 mL of 4 percent articaine HCl plus 1:200,000 epinephrine (A200). METHODS: During two testing sessions, the authors administered injections of A100 and A200 over a seven-minute period (in one-cartridge doses unless otherwise noted): maxillary right first molar infiltration, maxillary left first molar infiltration, maxillary right first premolar infiltration, maxillary left first premolar infiltration, right inferior alveolar injection, left inferior alveolar injection, right long buccal infiltration (one-half cartridge) and left long buccal infiltration (one-half cartridge). They analyzed venous blood samples for articaine levels. They used noninvasive acoustic tonometry to measure a variety of cardiovascular parameters over a two-hour period. RESULTS: Plasma concentration curves of articaine over time were similar for both solutions, with peak concentrations and times to maximum concentration being 2,037 nanograms per milliliter and 22 minutes for A100 and 2,145 ng/mL and 22 minutes for A200. At the 10-minute point, the mean systolic blood pressure and heart rate were significantly elevated (P < .05) with A100 versus A200. CONCLUSIONS: Maximum dose recommendations for the A100 solution also can be applied to the A200 solution. A200 produces less cardiovascular stimulation than does A100. CLINICAL IMPLICATIONS: A200 is as safe as A100, and may be preferable to A100 in patients with cardiovascular disease and in those taking drugs that reportedly enhance the systemic effects of epinephrine. 相似文献
8.
Zainul A Rajion Grant C Townsend David J Netherway Peter J Anderson Toby Hughes Ibrahim L Shuaib Ahmad Sukari Halim Abdul Rani Samsudin Neil R McLean David J David 《The Cleft palate-craniofacial journal》2006,43(5):532-538
OBJECTIVE: To compare morphological and positional variations of the hyoid bone in unoperated infants with cleft lip and palate (CL/P) with those in noncleft infants. DESIGN: Retrospective, cross sectional. PATIENTS AND METHODS: Three-dimensional computed tomography scans were obtained from 29 unoperated CL/P infants of Malay origin aged between 0 and 12 months and from 12 noncleft infants in the same age range. Observations were made and measurements were obtained with a software package developed at the Australian Craniofacial Unit. The sizes of the hyoid bones and the position of the hyoid body and epiglottis in relation to the cervical spine were measured. Anatomical anomalies of the hyoid and prevalence of aspiration pneumonia were also documented. RESULTS: The hyoid bones and epiglottis were found to be located more inferiorly in CL/P infants compared with the noncleft infants. Also, 17% (5/29) of the CL/P infants had nonossified hyoid bodies. CONCLUSION: The results suggest that there are differences in the location and genesis of the hyoid bone in infants with CL/P that warrant further investigation. 相似文献
9.
Emma Jane Bell John Kaidonis Grant Townsend Lindsay Richards 《Australian dental journal》1998,43(5):362-366
The aim of this study was to compare the shape of exposed dentinal surfaces caused by abrasion and erosion with a view to developing a diagnostic clinical test. The study material consisted of 80 natural teeth and 129 dental models obtained from Australian Aborigines known to display considerable dental abrasion due to their diet, and dental models of 37 Caucasians diagnosed with dental erosion through detailed history and dietary analysis. Polyvinyl siloxane impressions were obtained of all occlusal surfaces with dentinal scooping in both the ‘abrasion’ and ‘erosion’ groups. All impressions were sectioned buccolingually through the deepest point of the scooped dentine, and then the profiles were photocopied at X 2 magnification. The breadth and depth of dentinal profiles were measured to an accuracy of 0.1 mm, enabling ratios of depth:breadth to be determined, and the position of the deepest part of each scooped surface was recorded. The mean depth:breadth ratio of scooped dentine was significantly greater in the Aboriginal natural teeth (0. 19±60.06, mean±SE) than in the Aboriginal dental models (0.15±0.04). Both Aboriginal natural teeth and models with abrasion showed significantly smaller ratios (p<0.05) than the Caucasian models showing erosion (0.33±.07). Furthermore, in the abrasion samples, the deepest region of the scooped dentine tended to be lingually placed more often in maxillary teeth but buccally placed more often in mandibular teeth (p<0.05). These results indicate that scooped dentine on abraded occlusal surfaces of teeth displays significant differences in shape compared with that caused mainly by erosion. 相似文献
10.
Grant Townsend BDS BScDent PhD Lindsay Richards BDS BScDent PhD 《Australian dental journal》1990,35(4):317-327
Comparisons of physical features within identical (monozygous) and non-identical (dizygous) twin pairs have provided valuable insights into the relative contributions of genetic and environmental influences to observed variability. The special nature of the twinning process itself also provides an opportunity to learn more about early human development, including how body symmetry is determined. The mechanisms of twinning, mortality and morbidity in twins, determination of body symmetry including the phenomenon of mirror-imaging, postnatal growth and development of twins, and zygosity determination are discussed. Twin studies with direct relevance to clinical dentistry are reviewed and illustrated by examples from an ongoing investigation of dentofacial morphology in South Australian twins. 相似文献