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951.
S Fang J McLaughlin J Fang J Huang I Autti‐Rämö Å Fagerlund SW Jacobson LK Robinson HE Hoyme SN Mattson E Riley F Zhou R Ward ES Moore T Foroud 《Orthodontics & craniofacial research》2008,11(3):162-171
OBJECTIVES: Use three-dimensional (3D) facial laser scanned images from children with fetal alcohol syndrome (FAS) and controls to develop an automated diagnosis technique that can reliably and accurately identify individuals prenatally exposed to alcohol. METHODS: A detailed dysmorphology evaluation, history of prenatal alcohol exposure, and 3D facial laser scans were obtained from 149 individuals (86 FAS; 63 Control) recruited from two study sites (Cape Town, South Africa and Helsinki, Finland). Computer graphics, machine learning, and pattern recognition techniques were used to automatically identify a set of facial features that best discriminated individuals with FAS from controls in each sample. RESULTS: An automated feature detection and analysis technique was developed and applied to the two study populations. A unique set of facial regions and features were identified for each population that accurately discriminated FAS and control faces without any human intervention. CONCLUSION: Our results demonstrate that computer algorithms can be used to automatically detect facial features that can discriminate FAS and control faces. 相似文献
952.
OBJECTIVE: The aim of this study is to determine whether gingival crevicular fluid (GCF) dipeptidyl peptidase (DPP) II or IV levels, total activity (TA) and concentration (EC), predict progressive attachment loss (AL). SUBJECTS AND METHODS: Seventy five patients with moderate periodontitis were recruited. GCF was first collected from 16 molar and premolar mesiobuccal sites and then probing attachment level (PAL) and probing pocket depth (PPD) were measured with an electronic probe. Finally, gingival index, gingival bleeding and plaque indices were scored. Patients were given basic periodontal treatment prior to baseline after which the above procedures were repeated. Patients were seen 3 monthly for 2 years and the procedures were repeated. Carefully localised radiographs were taken of the test teeth annually. RESULTS: One hundred and twenty AL sites, 88 rapid AL (RAL) and 32 gradual AL (GrAL), in 48 patients were detected. DPP It and IV levels (TA and EC) at RAL sites were significantly higher (P ≤ 0.0001) than paired control sites at the attachment loss time (ALT) and prediction time (PT). Mean levels over the study period of both proteases (TA and EC) at GrAL sites were significantly higher (P≤ 0.0001) than paired control sites. The GCF levels of DPP IV were always slightly higher than those of DPP II. Critical values (CV) of 5 μU per 30 s (TA) and 25 μU μPI-1 (EC) for both proteases showed high sensitivity and specificity values for TA and EC and these were the same at both ALT and PT. The positive predictive values were slightly higher for DPP II. Mean site DPP II and IV levels (TA and EC) in intra-patient comparisons were significantly higher (P ≤ 0.0001) at RAL and GrAL sites than non-attachment loss (NAL) sites in AL patients and mean patient levels were significantly higher (P ≤ 0.0001) in AL patients than NAL patients in inter-patient comparisons. CONCLUSIONS: These results indicate that both GCF DPP II and IV may be predictors of periodontal attachment loss. 相似文献
953.
目的:介绍一种矫正纽扣状畸形方法,认识该术式特点。方法:选择1995-01/2005-12在北华大学第一临床医学院手外科进行指背腱膜中央束重建的患者20例,男15例,女5例;年龄18~46岁。将伤指的外侧腱沿其纵轴分为两部分,其中背侧半(内侧束)在中节以远切断,掌侧半(外侧束)在近指根部水平切断。移位外侧腱的外侧束通过Cleland's韧带及部分屈肌腱鞘在远侧指间关节伸直条件下缝合固定。采用掌长肌腱之一半腱束游离移植。在中节指骨基底偏背侧用克氏针横行钻一骨孔,使掌长肌腱通过,移植腱在背侧交叉后,将移植腱与中央腱及两侧束编织缝合,使侧束、中央束及移植腱三者融为一体重建近侧指间关节的伸指功能。采用Caroli评定标准评估疗效,分3级:优、良、可。采用外侧腱外侧束的腱固定术来维持远侧指间关节关节的伸直位,在中央腱止点利用移植腱与中央腱、侧束近端缝合重建近侧指间关节的伸指功能。结果:本组共20例,按Caroli评定标准,优15例,良4例,可1例,优良率为95%。结论:该术式的最大特点是将伸腱装置复杂的动力结构变得简单化,易于掌握,是肌腱组织移植矫正创伤后钮扣状畸形的一种有效方法。 相似文献
954.
In the past two decades, the need for economic restructuring has served as a rationale for dismantling social programs in Canada. As it has been enacted, such social restructuring has disproportionately affected marginalized people, particularly women. In this article we explore the schism between the principles that underlie the development of healthy public policy and those that are driving current social policy development. Through this analysis we discuss the implications of policy development that is based upon principles of inequity, and we suggest that implementation of healthy public policy requires transformational change in the underlying principles of the social system. A policy shift based upon principles of equity and social justice has been espoused throughout the health promotion literature. We suggest that such a shift will be facilitated by strengthening collaborative relations among points of conflict within society and among policy makers and women's organizations. 相似文献
955.
956.
David F Schaeffer Daniel R Owen Howard J Lim Andrew K Buczkowski Stephen W Chung Charles H Scudamore David G Huntsman Sylvia SW Ng David A Owen 《BMC cancer》2010,10(1):59
Background
Pancreatic ductal adenocarcinoma is a lethal disease with a 5-year survival rate of 4% and typically presents in an advanced stage. In this setting, prognostic markers identifying the more agrressive tumors could aid in managment decisions. Insulin-like growth factor 2 mRNA binding protein 3 (IGF2BP3, also known as IMP3 or KOC) is an oncofetal RNA-binding protein that regulates targets such as insulin-like growth factor-2 (IGF-2) and ACTB (beta-actin). 相似文献957.
Strain JJ Davidson PW Bonham MP Duffy EM Stokes-Riner A Thurston SW Wallace JM Robson PJ Shamlaye CF Georger LA Sloane-Reeves J Cernichiari E Canfield RL Cox C Huang LS Janciuras J Myers GJ Clarkson TW 《Neurotoxicology》2008,29(5):776-782
Fish consumption during gestation can provide the fetus with long-chain polyunsaturated fatty acids (LCPUFA) and other nutrients essential for growth and development of the brain. However, fish consumption also exposes the fetus to the neurotoxicant, methyl mercury (MeHg). We studied the association between these fetal exposures and early child development in the Seychelles Child Development Nutrition Study (SCDNS). Specifically, we examined a priori models of Omega-3 and Omega-6 LCPUFA measures in maternal serum to test the hypothesis that these LCPUFA families before or after adjusting for prenatal MeHg exposure would reveal associations with child development assessed by the BSID-II at ages 9 and 30 months. There were 229 children with complete outcome and covariate data available for analysis. At 9 months, the PDI was positively associated with total Omega-3 LCPUFA and negatively associated with the ratio of Omega-6/Omega-3 LCPUFA. These associations were stronger in models adjusted for prenatal MeHg exposure. Secondary models suggested that the MeHg effect at 9 months varied by the ratio of Omega-6/Omega-3 LCPUFA. There were no significant associations between LCPUFA measures and the PDI at 30 months. There were significant adverse associations, however, between prenatal MeHg and the 30-month PDI when the LCPUFA measures were included in the regression analysis. The BSID-II mental developmental index (MDI) was not associated with any exposure variable. These data support the potential importance to child development of prenatal availability of Omega-3 LCPUFA present in fish and of LCPUFA in the overall diet. Furthermore, they indicate that the beneficial effects of LCPUFA can obscure the determination of adverse effects of prenatal MeHg exposure in longitudinal observational studies. 相似文献
958.
Davidson PW Jean-Sloane-Reeves Myers GJ Hansen ON Huang LS Georger LA Cox C Thurston SW Shamlaye CF Clarkson TW 《Neurotoxicology》2008,29(3):453-459
The Seychelles Child Development Study was designed to test the hypothesis that prenatal exposure to MeHg from maternal consumption of a diet high in fish is detrimental to child neurodevelopment. To date, no consistent pattern of adverse associations between prenatal exposure and children's development has appeared. In a comprehensive review of developmental studies involving MeHg, a panel of experts recommended a more consistent use of the same endpoints across studies to facilitate comparisons. Both the SCDS and the Faeroe Islands studies administered the Bender Visual Motor Gestalt Test. However, the method of test administration and scoring used was different. We repeated the test on the SCDS Main Study children (mean age 10.7 years) using the same testing and scoring procedure reported by the Faeroe studies to obtain Copying Task and Reproduction Task scores. We found no association between prenatal MeHg exposure and Copying Task scores which was reported from the Faeroese study. However, our analysis did show a significant adverse association between MeHg and Reproduction Task scores with all the data (p=0.04), but not when the single outlier was removed (p=0.07). In a population whose exposure to MeHg is from fish consumption, we continue to find no consistent adverse association between MeHg and visual motor coordination. 相似文献
959.
CD133 expression is not restricted to stem cells, and both CD133+ and CD133- metastatic colon cancer cells initiate tumors 下载免费PDF全文
Shmelkov SV Butler JM Hooper AT Hormigo A Kushner J Milde T St Clair R Baljevic M White I Jin DK Chadburn A Murphy AJ Valenzuela DM Gale NW Thurston G Yancopoulos GD D'Angelica M Kemeny N Lyden D Rafii S 《The Journal of clinical investigation》2008,118(6):2111-2120
Colon cancer stem cells are believed to originate from a rare population of putative CD133+ intestinal stem cells. Recent publications suggest that a small subset of colon cancer cells expresses CD133, and that only these CD133+ cancer cells are capable of tumor initiation. However, the precise contribution of CD133+ tumor-initiating cells in mediating colon cancer metastasis remains unknown. Therefore, to temporally and spatially track the expression of CD133 in adult mice and during tumorigenesis, we generated a knockin lacZ reporter mouse (CD133lacZ/+), in which the expression of lacZ is driven by the endogenous CD133 promoters. Using this model and immunostaining, we discovered that CD133 expression in colon is not restricted to stem cells; on the contrary, CD133 is ubiquitously expressed on differentiated colonic epithelium in both adult mice and humans. Using Il10-/-CD133lacZ mice, in which chronic inflammation in colon leads to adenocarcinomas, we demonstrated that CD133 is expressed on a full gamut of colonic tumor cells, which express epithelial cell adhesion molecule (EpCAM). Similarly, CD133 is widely expressed by human primary colon cancer epithelial cells, whereas the CD133- population is composed mostly of stromal and inflammatory cells. Conversely, CD133 expression does not identify the entire population of epithelial and tumor-initiating cells in human metastatic colon cancer. Indeed, both CD133+ and CD133- metastatic tumor subpopulations formed colonospheres in in vitro cultures and were capable of long-term tumorigenesis in a NOD/SCID serial xenotransplantation model. Moreover, metastatic CD133- cells form more aggressive tumors and express typical phenotypic markers of cancer-initiating cells, including CD44 (CD44+CD24-), whereas the CD133+ fraction is composed of CD44lowCD24+ cells. Collectively, our data suggest that CD133 expression is not restricted to intestinal stem or cancer-initiating cells, and during the metastatic transition, CD133+ tumor cells might give rise to the more aggressive CD133(- )subset, which is also capable of tumor initiation in NOD/SCID mice. 相似文献
960.
Rebecca C. Thurston Karen A. Matthews Javier Hernandez and Fernando De La Torre 《Psychophysiology》2009,46(2):285-292
Hot flashes are experienced by over 70% of menopausal women. Criteria to classify hot flashes from physiologic signals show variable performance. The primary aim was to compare conventional criteria to Support Vector Machines (SVMs), an advanced machine learning method, to classify hot flashes from sternal skin conductance. Thirty women with ≥4 hot flashes/day underwent laboratory hot flash testing with skin conductance measurement. Hot flashes were quantified with conventional (≥2 μmho, 30 s) and SVM methods. Conventional methods had poor sensitivity (sensitivity=0.41, specificity=1, positive predictive value (PPV)=0.94, negative predictive value (NPV)=0.85) in classifying hot flashes, with poorest performance among women with high body mass index or anxiety. SVM models showed improved performance (sensitivity=0.89, specificity=0.96, PPV=0.85, NPV=0.96). SVM may improve the performance of skin conductance measures of hot flashes. 相似文献