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Central giant cell lesion of the jaws (CGCLJ) is a destructive condition that shows a varied and unpredictable biological behaviour. In the present study, we aimed to evaluate factors associated with the recurrence of CGCLJ. Based on the data of a previous systematic review of 2270 cases of CGCLJ, we used the multiple imputation to deal with the missing data. The dependent variable was the recurrence after the first treatment (yes/no). The dichotomic covariates were sex, upper or lower jaw location, size (up to or larger than 4 cm), pain, cortical bone perforation (yes/no), locularity (uni‐/multilocular), tooth displacement (yes/no), treatment type (curettage or enucleation) and root resorption (yes/no). The final logistic model indicated that the tumours associated with tooth displacement, root resorption and treated with curettage had a more significant chance of recurrence. In conclusion, our study suggests that tooth displacement, root resorption and the type of treatment are potentially useful in the future construction of an algorithm for patient's treatment.  相似文献   
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Objectives.— We investigated (1) a possible relationship between the functional activity of the endocannabinoid system and the facilitation of pain processing in migraineurs with medication‐overuse headache, and (2) the effect of withdrawal treatment on both. Background.— The endocannabinoid system antinociception effect includes prevention of nociceptive pathways sensitization. The sensitization of the pain pathways has been demonstrated to be pivotal in the development and maintenance of chronic form of migraine, including medication‐overuse headache. Methods.— We used the temporal summation threshold of the nociceptive withdrawal reflex to explore the spinal cord pain processing, and the platelet activity of the enzyme fatty acid amide hydrolase to detect the functional state of the endocannabinoid system in 27 medication‐overuse headache subjects before and 10 and 60 days after a standard withdrawal treatment and compared results with those of 14 controls. Results.— A significantly reduced temporal summation threshold and increased related pain sensation was found in subjects before withdrawal treatment when compared with controls. A significant fatty acid amide hydrolase activity reduction coupled with a significant improvement (reduction) in facilitation of spinal cord pain processing (increase in temporal summation threshold and reduction in related pain sensation) was found in medication‐overuse headache subjects at both 10 and 60 days after withdrawal treatment when compared with medication‐overuse headache subjects before withdrawal treatment. Conclusions.— We demonstrated a marked facilitation in spinal cord pain processing in medication‐overuse headache before withdrawal treatment when compared with controls. Furthermore, the acute reduction of the fatty acid amide hydrolase activity coupled with a reduction of the facilitation in pain processing immediately (10 days) after withdrawal treatment and its persistence 60 days after withdrawal treatment could represent the consequence of a mechanism devoted to acutely reduce the degradation of endocannabinoids and aimed to increase the activity of the endocannabinoid system that results in an antinociceptive effect.  相似文献   
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There is evidence suggesting that exposure to an abnormal magnetic environment may produce psychophysiological effects related to abnormalities in responses to stress. This may be of relevance for space medicine where astronauts are exposed to a magnetic field different from that exerted by the Earth. Aim of this study was to assess how the exposure of the head to a magnetic field simulating the one encountered by the International Space Station (ISS) during a single orbit (90 min) around the Earth affects the cardiovascular and psychophysiological parameters. Twenty-four human volunteers were studied double blindly in random order under sham and magnetic exposure. During exposure, the persons were shown a set of pictures of different emotional content while subjective self-rating, skin conductance (SC), blood pressure (BP), and heart rate (HR) were measured. In addition, BP, HR, and tooth pain threshold were assessed before and after exposure. While subjects were under magnetic exposure, skin conductance was strongly differentiated (F2,36 = 22.927; p = 0.0001), being high during emotionally involving (positive and negative) pictures and low during neutral pictures. Conversely, when subjects were under sham exposure, no significant differences were observed. There was, however, a trend for higher heart rate during picture viewing under magnetic exposure as compared to sham exposure. No effects were found for the other variables. These results suggest that an abnormal magnetic field that simulates the one encountered by ISS orbiting around the Earth may enhance autonomic response to emotional stimuli.  相似文献   
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