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111.
2,5‐Dimethylfuran (DMF) is being considered as a potential green transportation biofuel, but there is limited information about its toxicity and safety. We examined DMF toxicity in the bone marrow using a murine in vitro erythropoietic micronucleus assay and found that exposure to DMF (0.1 mM, 1 hr) induced an increase in micronuclei frequency compared with controls. These data suggest that DMF may be genotoxic to hematopoietic cells and that more thorough toxicological studies on DMF should be conducted to ensure public and occupational safety before it is considered a viable biofuel and produced in mass quantities. As well as specific data on DMF, our study further validates an in vitro cell culture system that captures the essential features of the in vivo mammalian micronucleus genotoxicity assay, enabling increased throughput and controlled studies on hematopoietic DNA damage response, while reducing animal sacrifice. In vitro assays, such as the in vitro micronucleus assay, will be essential as international chemical policy is increasingly utilizing green chemistry principles that require more toxicological testing. Environ. Mol. Mutagen. 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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Due to the HIV/AIDS pandemic which has left 12 million children orphaned in Sub-Saharan Africa, children are at increased risk for mental health problems. Currently, no validity data exist for any screening measure of emotional-behavior disorders in pre-adolescent children in Sub-Saharan Africa. The aims of the current study were to evaluate the construct validity of the caregiver-, teacher-, and self-report versions of the one-page Strengths and Difficulties Questionnaire (SDQ) in 466 orphans in South Africa between the ages of 7 and 11 (M age = 9.23 years, SD = 1.33, 51.93 % female) and to provide, for the first time, clinical cut-offs for this population. Findings demonstrated support for the caregiver SDQ, but not the teacher and self-report versions. We provide clinical cut-offs, but caution their use before further research is conducted. There remains a critical need for further psychometric studies of the SDQ in the developing world.  相似文献   
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Offspring of parents with exceptional longevity (OPEL), who are more likely to carry longevity-associated genotypes, may age more successfully than offspring of parents with usual survival (OPUS). Maintenance of physical function is a key attribute of successful aging. While many genetic and non-genetic factors interact to determine physical phenotype in aging, examination of the contribution of exceptional parental longevity to physical function in aging is limited. The LonGenity study recruited a relatively genetically homogenous cohort of Ashkenazi Jewish (AJ) adults age 65 and older, who were defined as either OPEL (having at least one parent who lived to age 95 or older) or OPUS (neither parent survived to age 95). Subjective and objective measures of physical function were compared between the two groups, accounting for potential confounders. Of the 893 LonGenity subjects, 365 were OPEL and 528 were OPUS. OPEL had better objective and subjective measures of physical function than OPUS, especially on unipedal stance (p = 0.009) and gait speed (p = 0.002). Results support the protective role of exceptional parental longevity in preventing decline in physical function, possibly via genetic mechanisms that should be further explored.  相似文献   
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Since its identification as a unique species in 1982, Escherichia hermannii has only recently been implicated as a pathogenic organism in human diseases. Literature search indicates removal of hemodialysis catheter as being essential to the success of treatment for bacteremia with this organism. However, having no alternative access for hemodialysis led to the attempt to salvage the catheter with the use of Antibiotic lock therapy. This case highlights Antibiotic lock therapy as an indication in Escherichia hermanii Catheter related Bloodstream infection.  相似文献   
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The use of social media opens content to the general public and, as a result, places images of cadaveric dissection in an open forum. This raises the question: should the general public have access to such material? A survey was conducted examining whether the general public should have access to gross cadaveric dissection images and videos for educational purposes via social media. Both medical and laypersons were queried. Questions included in the survey considered whether images were too graphic, whether online cadaveric content should be age‐restricted, and whether consent by the deceased was necessary. A link to the survey was accessible to 63,562 followers through the Seattle Science Foundation's Facebookpage for 3 weeks. Among 300 responders, 89% (267/300) agreed that portrayals of cadaveric specimens/dissection on social media should be accessible by the general public for anatomical education, and 84.67% (254/300) stated that cadaveric dissection is not too graphic for untrained eyes. There was agreement by 60.33% (181/300) that an age restriction should be in place for the viewing of cadaveric dissection on social media, and 39.33% (253/300) of responders suggested restriction to 18 years and older. No statistically significant association was noted between a prior or current history of anatomy education and the frequency of positive responses to the survey questions. Social media is an innovative tool for dispensing anatomical education. The use of cadaveric images and videos provides accessibility to the general public who wish to learn more about human anatomy and their own body. Clin. Anat. 32:1033–1041, 2019. © 2019 Wiley Periodicals, Inc.  相似文献   
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Most of the studies of the mandible's anatomical variations have presented the authors' speculations, and only a limited number has provided evidence that demonstrated the actual complications injury to the variant structures caused. To our knowledge, no study has evaluated the risks associated with these variant anatomical structures' injury. We reviewed articles that described clinical cases of the injury to, and anatomical studies of, three anatomical variants of the mandible—the accessory mental, lingual, and retromolar foramina—with which dentists are relatively familiar and that are mentioned often in the context of implant and third molar surgeries, to describe risk assessment methods with which to evaluate potential complications preoperatively. Only a limited number of the clinical reports of injury to the mandible's accessory foramina were available. The potential severe complication of injury of the accessory mental foramen (AMF) is sensory disturbance of the lower lip. Risk of neurosensory disturbance of lower lip can be assessed by AMF/MF ratio and positional relations to the MF. Potential severe complication of injury of the lingual foramen is bleeding and hemorrhage in the oral cavity's floor. Risk of bleeding can be assessed by diameter and positional relation between the mental spine/mylohyoid line. A risk assessment of the retromolar foramen could not be made because of inadequate data. We hope the risk assessments suggested will encourage dentists to predict intraoperative/postoperative complications caused by damaging the mandible's accessory foramina. Clin. Anat. 32:672–677, 2019. © 2019 Wiley Periodicals, Inc.  相似文献   
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