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肠运动存在昼夜节律,表现为白天活跃,夜间减弱或消失,这是一种内生性的、由时钟基因控制的生物节律。肠运动节律既可与中央节律保持高度一致,也可独立于中央节律而对外周环境刺激做出反馈。外科手术会破坏肠运动的昼夜节律,而围手术期合理使用褪黑素、五羟色胺(5-HT)受体激动剂和非甾体类解热镇痛药等药物则有助于促进此节律的恢复。外科医生了解肠运动节律的机制,有助于加深术后肠麻痹(POI)的认识,再基于时辰药理学,在合适的时机以适宜的剂量给药,或许能进一步缩短POI时间,促进肠运动功能尽早恢复。 相似文献
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目的 探讨基于正交试验的肾造瘘管不同固定方案的比较效果。方法 将14Fr硅胶肾造瘘管固定在聚乙烯展板和拉力显示器上,以固定材料、固定方法、面积为3个影响因素,每个因素3个水平,每组进行3次试验再求平均值作为最后拉力值F,共进行9个固定方案共27次试验。利用L9(33)正交试验矩阵研究不同材料(医用橡皮膏、医用透气胶带、医用无纺布胶带)、固定方法(交叉固定法、“工”字固定法和改良“工”字固定法)及面积(16 cm2、24 cm2、32 cm2)对肾造瘘管固定强度的影响。结果 正交试验所选的3种影响因素中,对拉力值影响显著性排序为:材料>方法>面积;3种固定材料中,医用橡皮膏固定强度最大。结论 肾造瘘管固定方案中,最佳固定组合为以医用橡皮膏结合改良“工”字法固定,可为临床管道固定方案的选择提供参考。 相似文献
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《Clínica e investigación en ginecología y obstetricia》2022,49(2):100738
We report a rare case of uterine carcinosarcoma involving a 74-year-old woman. The patient complained of posmenopausal bleeding. The disease was eventually diagnosed as simultaneous uterine carcinosarcoma and high-grade serous tubal carcinoma.Clinical examination found a cervical tumour and transvaginal ultrasound showed a heterogeneous intrauterine image. The histological result of both findings was carcinosarcoma.The computed tomography scan and magnetic resonance imaging reported similar findings for intrauterine and cervical tumour, with the same features as a possible myoma or mass with sarcomatous degeneration.Given the suspicion of a high-risk variant of endometrial adenocarcinoma, the primary management of carcinosarcoma is surgery. Complete surgical staging included total hysterectomy, bilateral salpingo-oophorectomy, omentectomy, pelvic and para-aortic lymph node dissection.The pathological findings revealed a uterine carcinosarcoma tumour, invading less than half the myometrium and the stromal connective tissue of the cervix but not extending beyond the uterus. The histopathological studies of bilateral adnexectomy and the peritoneal biopsy demonstrated the presence of high-grade serous tubal carcinoma. The lymph study was negative for malignancy.We concluded a synchronous diagnosis of uterine carcinosarcoma stage II and high-grade serous tubal carcinoma stage IIIB.A detailed literature search and management of this entity are discussed. 相似文献
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Tobias Hüppe Sascha Kreuer Hinnerk Wulf Dennik Freitag Martin Seidel Tobias Teucke Felix Maurer Andreas Kirschbaum Tilo Koch Frank Langer Thomas Volk Carsten Feldmann 《Acta anaesthesiologica Scandinavica》2023,67(4):455-461
Background
Volatile propofol can be measured in exhaled air and correlates to plasma concentrations with a time delay. However, the effect of single-lung ventilation on exhaled propofol is unclear. Therefore, our goal was to evaluate exhaled propofol concentrations during single-lung compared to double-lung ventilation using double-lumen tubes.Methods
In a first step, we quantified adhesion of volatile propofol to the inner surface of double-lumen tubes during double- and single-lumen ventilation in vitro. In a second step, we enrolled 30 patients scheduled for lung surgery in two study centers. Anesthesia was provided with propofol and remifentanil. We utilized left-sided double-lumen tubes to separately ventilate each lung. Exhaled propofol concentrations were measured at 1-min intervals and plasma for propofol analyses was sampled every 20 min. To eliminate the influence of dosing on volatile propofol concentration, exhalation rate was normalized to plasma concentration.Results
In-vitro ventilation of double-lumen tubes resulted in increasing propofol concentrations at the distal end of the tube over time. In vitro clamping the bronchial lumen led to an even more pronounced increase (Δ AUC +62%) in propofol gas concentration over time. Normalized propofol exhalation during lung surgery was 31% higher during single-lung compared to double-lung ventilation.Conclusion
During single-lung ventilation, propofol concentration in exhaled air, in contrast to our expectations, increased by approximately one third. However, this observation might not be affected by change in perfusion-ventilation during single-lung ventilation but rather arises from reduced propofol absorption on the inner surface area of the double-lumen tube. Thus, it is only possible to utilize exhaled propofol concentration to a limited extent during single-lung ventilation.Registration of Clinical Trial
DRKS-ID DRKS00014788 ( www.drks.de ). 相似文献8.
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Dan-Dan Shan Qiu-Xian Zheng Jing Wang Zhi Chen 《World journal of gastroenterology : WJG》2022,28(16):1641-1655
Cancer has become the most life-threatening disease in the world. Mutations in and aberrant expression of genes encoding proteins and mutations in noncoding RNAs, especially long noncoding RNAs (lncRNAs), have significant effects in human cancers. LncRNAs have no protein-coding ability but function extensively in numerous physiological and pathological processes. Small nucleolar RNA host gene 3 (SNHG3) is a novel lncRNA and has been reported to be differentially expressed in various tumors, such as liver cancer, gastric cancer, and glioma. However, the interaction mechanisms for the regulation between SNHG3 and tumor progression are poorly understood. In this review, we summarize the results of SNHG3 studies in humans, animal models, and cells to underline the expression and role of SNHG3 in cancer. SNHG3 expression is upregulated in most tumors and is detrimental to patient prognosis. SNHG3 expression in lung adenocarcinoma remains controversial. Concurrently, SNHG3 affects oncogenes and tumor suppressor genes through various mechanisms, including competing endogenous RNA effects. A deeper understanding of the contribution of SNHG3 in clinical applications and tumor development may provide a new target for cancer diagnosis and treatment. 相似文献