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1.
Tympanic membranes (TM) that have healed spontaneously after perforation present abnormalities in their structural and mechanical properties; i.e., they are thickened and abnormally dense. These changes result in a deterioration of middle ear (ME) sound transmission, which is clinically presented as a conductive hearing loss (CHL). To fully understand the ME sound transmission under TM pathological conditions, we created a gerbil model with a controlled 50% pars tensa perforation, which was left to heal spontaneously for up to 4 weeks (TM perforations had fully sealed after 2 weeks). After the recovery period, the ME sound transmission, both in the forward and reverse directions, was directly measured with two-tone stimulation. Measurements were performed at the input, the ossicular chain, and output of the ME system, i.e., at the TM, umbo, and scala vestibuli (SV) next to the stapes. We found that variations in ME transmission in forward and reverse directions were not symmetric. In the forward direction, the ME pressure gain decreased in a frequency-dependent manner, with smaller loss (within 10 dB) at low frequencies and more dramatic loss at high frequency regions. The loss pattern was mainly from the less efficient acoustical to mechanical coupling between the TM and umbo, with little changes along the ossicular chain. In the reverse direction, the variations in these ears are relatively smaller. Our results provide detailed functional observations that explain CHL seen in clinical patients with abnormal TM, e.g., caused by otitis media, that have healed spontaneously after perforation or post-tympanoplasty, especially at high frequencies. In addition, our data demonstrate that changes in distortion product otoacoustic emissions (DPOAEs) result from altered ME transmission in both the forward and reverse direction by a reduction of the effective stimulus levels and less efficient transfer of DPs from the ME into the ear canal. This confirms that DPOAEs can be used to assess both the health of the cochlea and the middle ear.  相似文献   
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Post-induction hypotension is common and associated with postoperative complications. We hypothesised that pneumatic leg compression reduces post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy. In this double-blind randomised study, patients were allocated randomly to the pneumatic leg compression group (n = 50) or control (n = 50). In the intervention group, pneumatic leg compression was initiated before induction of anaesthesia. In the control group, pneumatic leg compression was initiated 20 min after anaesthesia induction. The primary outcome was the incidence of post-induction hypotension in these groups. Post-induction hypotension was defined as systolic blood pressure < 90 mmHg during the first 20 min after induction. Haemodynamic variables and area under the curve of post-induction systolic blood pressure over time were assessed. Complications associated with pneumatic leg compression were recorded, including: peripheral neuropathy; compartment syndrome; extensive bullae beneath the leg sleeves; and pulmonary thromboembolism. The incidence of post-induction hypotension decreased in the pneumatic leg compression group compared with that in the control group; 5 (10%) vs. 29 (58%), respectively, p < 0.001. In the pneumatic leg compression group, the lowest systolic, diastolic and mean blood pressures 20 min after induction of anaesthesia were significantly greater than the control group. Pneumatic leg compression resulted in an increased area under the curve of systolic blood pressure in the first 20 min after induction, p = 0.001. There were no pneumatic leg compression-related complications. Pneumatic leg compression reduced post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy, suggesting that it is an effective and safe intervention to prevent post-induction hypotension among elderly patients undergoing general anaesthesia.  相似文献   
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郑茂  邹玉  王洁莹  况南珍  傅颖媛 《安徽医药》2022,26(11):2198-2202
目的探讨瑞香素(DAP)通过含半胱氨酸的天冬氨酸蛋白水解酶(caspase)通路对胶原诱导性关节炎(CIA)大鼠成纤维样滑膜细胞(FLS)增殖与凋亡的影响。方法体外培养 CIA-FLS,选取对数生长期细胞以不同浓度 DAP(0、5、10、20、40、80 mg/  相似文献   
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<正>克兰费尔特综合征(Klinefelter’s syndrome,KS)简称克氏综合征,属于先天性疾病。由于额外增加至少1条X染色体导致睾丸曲细精管发育异常,KS表现为青春发育不完全和精子生成障碍。迄今为止,对于KS合并中枢性性早熟(central precocious puberty,CPP)或青春早发育快进展,国内外鲜有报道。本文报道1例47,XXY KS合并青春早发育快进展患者,并通过文献复习探讨其可能的发病机制和治疗措施,以提高对该病的认识。  相似文献   
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目的 开展养老机构志愿者预立医疗照护计划培训并评价其效果。方法 应用基于Bloom目标教学理论构建的养老机构志愿者预立医疗照护计划培训内容,结合《预立医疗照护计划》知识教育手册、《我的五个愿望》手册、案例视频等教具,通过角色扮演、案例讨论等方式对53名养老机构志愿者进行培训。培训前后使用养老机构志愿者预立医疗照护计划知信行及自我效能问卷对志愿者进行调查,根据志愿者角色扮演表现评价其预立医疗照护计划沟通技能。结果 培训前后志愿者预立医疗照护计划认知、态度、行为意愿及自我效能差异有统计学意义(P<0.05,P<0.01),培训后75.47%志愿者预立医疗照护计划沟通技能达合格及以上水平。结论 预立医疗照护计划培训能改善养老机构志愿者的预立医疗照护计划知信行及自我效能感,培养其预立医疗照护计划沟通能力。  相似文献   
9.
目的 降低神经外科术中获得性压力性损伤发生率。 方法 将2019年10~12月的1 378例神经外科择期手术患者作为对照组,采取常规护理措施预防术中获得性压力性损伤。将2020年10~12月的1 551例患者作为观察组,成立护理专案小组,开展多学科协作,实施护理专案改善。 结果 观察组术中获得性压力性损伤发生率为0.90%,对照组为2.18%,两组比较,差异有统计学意义(P<0.05);两组术中获得性压力性损伤治愈率比较,差异无统计学意义(P>0.05)。观察组预防术中获得性压力性损伤关键监测指标落实率较好,除术后规范交接班落实875例(61.40%)外,其他指标均>88.00%。 结论 多学科协作护理专案能够有效降低术中获得性压力性损伤发生率,提高术中获得性压力性损伤预防和管理质量。  相似文献   
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Gastrointestinal cancer (GIC) is the most common cancer with a poor prognosis. Currently, surgery is the main treatment for GIC. However, the high rate of postoperative recurrence leads to a low five-year survival rate. In recent years, immunotherapy has received much attention. As the only immunotherapy drugs approved by the Food and Drug Administration (FDA), immune checkpoint blockade (ICB) drugs have great potential in cancer therapy. Nevertheless, the efficacy of ICB treatment is greatly limited by the low immunogenicity and immunosuppressive microenvironment of GIC. Therefore, the targets of immunotherapy have expanded from ICB to increasing tumor immunogenicity, increasing the recruitment and maturation of immune cells and reducing the proportion of inhibitory immune cells, such as M2-like macrophages, regulatory T cells and myeloid-derived suppressor cells. Moreover, with the development of nanotechnology, a variety of nanoparticles have been approved by the FDA for clinical therapy, so novel nanodrug delivery systems have become a research focus for anticancer therapy. In this review, we summarize recent advances in the application of immunotherapy-based nanoparticles in GICs, such as gastric cancer, hepatocellular carcinoma, colorectal cancer and pancreatic cancer, and described the existing challenges and future trends.  相似文献   
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