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61.
The mechanism of gastrointestinal dysmotility in inflammatory bowel disease has not been clarified. In this study, we examined the mechanism involved in the inflamed distal colon isolated from a mouse model of dextran sodium sulphate-induced ulcerative colitis (DSS-treated mouse). Although substance P-induced contraction was not changed, carbachol-induced contraction was reduced in the DSS-treated mouse colon. Pre-incubation with the NO synthase inhibitor N(G)-monomethyl-L-arginine (L-NMMA) or the cyclooxygenase inhibitor indomethacin did not reverse the carbachol-induced contraction in the DSS-treated mouse colon. In semi-quantitative reverse transcription-polymerase chain reaction experiments and Western blot analysis, muscarinic M3 receptor expressions were not changed. The Ca2+ -sensitization of contractile elements induced by carbachol with GTP or GTPgammaS was reduced in the beta-escin-permeabilized DSS-treated mouse colon. Although the expression of proteins such as rhoA, ROCK1, ROCK2 or MYPT1 in smooth muscles was not changed, the expression of CPI-17, the functional protein involved in smooth muscle Ca2+ -sensitization, was significantly decreased in the DSS-treated mouse colon. These results suggest that the suppression of carbachol-induced contraction in mice with colitis is attributable at least partially to the increased activity of myosin phosphatase following the downregulation of CPI-17.  相似文献   
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Hypoxia is related to poor prognosis because it is associated to chemo-and radioresistance. During recent years the evolution of imaging methods like PET/CT and MRI has meant the appearance of new perspectives with direct implications in radiation therapy. We discuss previous experiences in staging, planning and in the follow-up process with these techniques for measuring tumour hypoxia.  相似文献   
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Background&nbsp;&nbsp;Coccygodynia can cause severe pain and disability in patients. There are contradictions in the literature regarding the final results of coccygectomy for coccygodynia. We evaluated the long-term effects of coccygectomy on the intensity, characteristics, and manifestation of pain caused by coccygodynia to determine the adequacy of operation among treatment modalities. Materials and methods&nbsp;&nbsp;Thirty-four patients with coccygodynia were treated by coccygectomy. In 22 cases, trauma, and in one case childbirth was the cause. 11 cases were regarded as idiopathic. The intensity, characteristics of pain, and the most painful activities were evaluated at an average of 7.6 (3–18) years of follow-up time. Results&nbsp;&nbsp;Before the operation, all 34 patients had pain while sitting, moreover, 26 of them had pain during standing, walking, at night or a combination of these. 21 patients had intolerable or very intensive, mainly acute, sharp or burning pain. 11 patients had dyschesia, 2 had dysuria and 6 had dyspareunia. At follow-up, 7 patients were completely free of pain, 15 others had moderate, 11 medium, and only one patient had severe, but none had intolerable pain. Only seven patients had acute, sharp or burning pain postoperatively. The decrease of average pain score from 8.0 to 3.2 was significant (P&nbsp;<&nbsp;10<sup>−12sup>). The number of the patients with dyschesia and dyspareunia decreased from 11 to 7 and from 6 to 3, respectively. Two patients had dysuria, but their complaints did not change after the operation. One of the two patients who needed reoperation had an excellent final result, while the other remained unchanged. 12 and 16 patients (together 82%) regarded the final result of the operation excellent and good, respectively. The condition of five others did not change, while one became worse. The patients with younger age, smaller body mass index, and less co-morbidities had better final result. There were no serious complications. Conclusion&nbsp;&nbsp;Coccygectomy for coccygodynia is a safe method to decrease the intensity of pain and other complaints of the patients. The operation can be the choice of treatment if conservative measures fail.  相似文献   
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OBJECTIVES: To compare the sensitivity of rotational chair (ROTO) versus electronystagmography (ENG) in peripheral vestibular pathology. METHODS: Retrospective chart review. RESULTS: One thousand consecutive patients undergoing evaluation for dizziness and imbalance at a tertiary care referral balance center were reviewed. ROTO was the primary vestibular study used in all patients with ENG used as a confirmatory test at the discretion of the treating physician. A subgroup of 478 patients underwent both ROTO and ENG. Among the patients diagnosed with peripheral vestibulopathy, sensitivity for peripheral vestibulopathy was 71% for ROTO and 31% for ENG. However, specificity was 54% for ROTO and 86% for ENG. CONCLUSIONS: We conclude that in this retrospective cohort with the authors' clinical diagnoses, ROTO is a more sensitive diagnostic study of peripheral vestibular pathology. The higher sensitivity of ROTO and the higher specificity of ENG may support the use of ROTO as the primary vestibular study and ENG as a supplemental vestibular study. Prospective analysis with distinct diagnostic criteria and defined inclusion criteria are necessary before these results can be widely extrapolated.  相似文献   
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