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971.
Facial size reduction and facial retraction are key features that distinguish modern humans from archaic Homo. In order to more fully understand the emergence of modern human craniofacial form, it is necessary to understand the underlying evolutionary basis for these defining characteristics. Although it is well established that the cranial base exerts considerable influence on the evolutionary and ontogenetic development of facial form, less emphasis has been placed on developmental factors intrinsic to the facial skeleton proper. The present analysis was designed to assess anteroposterior facial reduction in a pig model and to examine the potential role that this dynamic has played in the evolution of modern human facial form. Ten female sibship cohorts, each consisting of three individuals, were allocated to one of three groups. In the experimental group (n = 10), microplates were affixed bilaterally across the zygomaticomaxillary and frontonasomaxillary sutures at 2 months of age. The sham group (n = 10) received only screw implantation and the controls (n = 10) underwent no surgery. Following 4 months of post‐surgical growth, we assessed variation in facial form using linear measurements and principal components analysis of Procrustes scaled landmarks. There were no differences between the control and sham groups; however, the experimental group exhibited a highly significant reduction in facial projection and overall size. These changes were associated with significant differences in the infraorbital region of the experimental group including the presence of an infraorbital depression and an inferiorly and coronally oriented infraorbital plane in contrast to a flat, superiorly and sagittally infraorbital plane in the control and sham groups. These altered configurations are markedly similar to important additional facial features that differentiate modern humans from archaic Homo, and suggest that facial length restriction via rigid plate fixation is a potentially useful model to assess the developmental factors that underlie changing patterns in craniofacial form associated with the emergence of modern humans.  相似文献   
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Fatigue is a common, disabling symptom for individuals with rheumatoid arthritis (RA). This study 1) examined sex differences in the relations between daily changes in positive and negative interpersonal events and same-day and next-day fatigue and 2) tested positive affect and negative affect as mediators of the associations between changes in interpersonal events and fatigue. Reports of fatigue, number of positive and negative interpersonal events, and positive and negative affect were assessed daily for 30 days via diaries in 228 men and women diagnosed with RA. Days of higher than average daily positive events were associated with both decreased same-day fatigue and increased next-day fatigue, but only among women. Sex differences in same-day relations between positive events and fatigue were mediated by increases in positive affect. For both sexes, days of higher than average daily negative events related to increased same-day and next-day fatigue, and the same-day relations between negative events and fatigue were mediated by increases in negative affect. A more nuanced understanding of similarities and differences between men and women in the associations between changes in interpersonal events and fatigue may inform future interventions for RA fatigue.  相似文献   
978.
Background and Aim:  Various methods have been used to remove self expandable stents (SES) because of either malposition or migration. The main difficulties encountered in such situations are the anatomic obstacle of the lower and upper esophageal sphincters as well as risk of mucosal injury during removal.
Methods:  We describe a modified approach using an esophagogastroduodenoscope (EGD) in combination with a foreign body hood protector, rat tooth forceps and snare allowing for successful SES removal from the upper gastrointestinal tract in four cases.
Results:  In all cases, the SES were successfully removed from upper gastrointestinal tract using this technique. No complications were noted after extraction.
Conclusion:  The foreign body hood protector combined with rat tooth forceps/snare technique is a safe and effective alternative to previously described methods for extraction of SES from the upper gastrointestinal tract. This method may be applicable for the removal of other such objects within the endoscope's reach.  相似文献   
979.

Background  

Lyme neuroborreliosis (LNB) may present as meningitis, cranial neuropathy, acute radiculoneuropathy or, rarely, as encephalomyelitis. We hypothesized that glia, upon exposure to Borrelia burgdorferi, the Lyme disease agent, produce inflammatory mediators that promote the acute cellular infiltration of early LNB. This inflammatory context could potentiate glial and neuronal apoptosis.  相似文献   
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