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361.
BACKGROUND: Nutcracker esophagus (NE) is a manometric finding defined by peristaltic contractions with a mean distal esophageal amplitude (DEA) >180 mm Hg. This threshold has been selected as it exceeds the average DEA in healthy volunteers by 2 SDs. Since its introduction the clinical significance of this finding has been challenged, as many patients with NE are asymptomatic. AIM: To evaluate whether defining NE based on a different DEA threshold would be clinically more meaningful. METHODS: Retrospective review of prospectively collected manometry data between October 2001 and December 2003. Using previously published normal DEA values (mean and SD) patients with NE were stratified into 3 groups: group A (2 to 3 SD above mean): DEA 180 to 220 mm Hg; group B (3 to 4 SD above mean): DEA 220 to 260 mm Hg; and group C (>4 SD above mean): DEA >260 mm Hg. Symptoms, esophageal acid exposure, bolus transit data, and lower esophageal sphincter data were reviewed. RESULTS: The stratification of 56 NE patients into groups A, B, and C were 31, 16, and 9, respectively. The proportion of patients presenting with chest pain increased from 23% in group A to 69% in group B and 100% in group C. Patients in group C had significantly (P<0.05) higher mean lower esophageal sphincter pressure, shorter bolus transit time, and lower frequency of abnormal reflux. CONCLUSIONS: A revised definition of NE to include patients with a DEA >260 mm Hg, and possibly those with >220 may have greater clinical relevance.  相似文献   
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Although occlusal and interproximal attrition occur because of diverse etiology and present dissimilar features, both progress with age. The objectives of this study were to reveal the rate and pattern of development of interproximal attrition facets (PAF) with age and to compare those with occlusal attrition (OA) changes. Five‐hundred and ninety‐four teeth were collected from 198 skulls (of adults, 20–71 yr of age). Three mandibular teeth [first premolar (P1), second premolar (P2), and first molar (M1)] were examined for PAF size and OA rate. Interproximal attrition and OA followed similar patterns of development until subjects reached 40–45 yr of age, after which they took different paths: PAF did not increase in size and were not as large as in younger groups, regardless of facet location, whereas OA continued to progress. The PAF changes with age differed between premolars and molars, unlike OA, which presented a similar rate for all teeth studied. Although OA scores presented significantly moderate correlations with age, PAF area size demonstrated low correlations with age. Low, but significant, correlations were found between the rate of OA and that of PAF. However, PAF and OA exhibited different patterns of development with age. Premolars and molars presented dissimilar development of PAF, which is probably caused by a unique attrition pattern in the molar teeth, different morphology, and force vectors.  相似文献   
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BackgroundChronic headache is one of the most prominent symptoms among subjects with traumatic head injury (THI). Despite the relatively high prevalence of chronic post-traumatic headache (CPTHA) and its enormous effect on the already poor quality of life of subjects with THI, its mechanisms has not been studied in depth.ObjectiveTo conducted quantitative somatosensory testing in THI subjects with and without chronic post-traumatic headache (CPTHA) in order to shed light on the yet, unknown pathophysiology of CPTHA.MethodsTHI subjects with and without CPTHA and healthy controls underwent thermal and mechanical threshold measurements in painful and pain-free regions in the head and in their hands (a remote pain-free region) and filled out and the post-traumatic stress disorder (PTSD) inventory. In addition, the THI and CPTHA filled out the Mc’Gill pain questionnaire (MPQ).ResultsTHI subjects with CPTHA had significantly higher thermal thresholds in both the head and hand indicating central damage to the pain and temperature system and in addition, a significantly lower pressure-pain threshold in the head as well as more severe PTSD symptomatology than the pain-free THI subjects and healthy controls.ConclusionsThe sensory profile of subjects with CPTHA suggests that CPTHA may be a form of central pain. The cranial mechanical hyperalgesia may originate from peripheral tissue damage accompanying the THI. Psychological factors may contribute to the development, and maintenance of CPTHA in susceptible individuals.  相似文献   
366.
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