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991.
目的 分析山西营养与慢性病家庭队列人群BMI与总死亡率的关系。方法 以"2002年中国居民营养与健康状况调查"山西省调查人群为基线建立队列,于2015年12月至2016年3月对研究对象进行随访调查,对逝者进行死因回顾调查。2002年基线信息完整的≥ 18岁研究对象7 007人,随访到5 360人,随访率为76.5%。将研究对象按BMI分为8组,计算死亡率,以死亡率最低组作为参照,采用Cox比例风险回归模型估计全人群、分性别、年龄(≥ 60岁、<60岁)的各组死亡风险比(HR)及95% CI,模型调整基线年龄、性别、吸烟、饮酒、文化程度等因素,并进行敏感性分析。结果 共随访67 129人年,平均随访12.5年,死亡615人,队列总死亡率为916/10万人年。BMI为26.0~27.9 kg/m2组死亡率最低,以该组为参照组,多因素调整后,BMI<18.5、18.5~19.9、22.0~23.9和≥ 30.0 kg/m2组的死亡风险明显升高,调整HR值(95% CI)分别为1.90(1.26~2.86)、1.68(1.15~2.45)、1.49(1.08~2.06)和1.72(1.07~2.76)。对于≥ 60岁老年人,BMI<18.5 kg/m2组的死亡风险明显升高,调整HR值(95% CI)为1.94(1.20~3.15)。结论 BMI ≤ 19.9、22.0~23.9及≥ 30.0 kg/m2均会增加全因死亡风险。除关注肥胖外,低体重营养不良造成的老年人高死亡风险应特别引起重视。  相似文献   
992.
孔圣枕中丹对痴呆动物模型抗凋亡作用及机制的研究   总被引:1,自引:0,他引:1  
目的:研究孔圣枕中丹抗痴呆动物模型海马神经元细胞凋亡的作用及机制。方法:将50只Wister大鼠随机分为正常组、模型组、脑复康组、孔圣枕中丹低剂量组、高剂量组,每组10只。除正常组外,将其余大鼠制成血管性痴呆大鼠模型。给大鼠灌胃后,采用流式细胞技术检测神经元凋亡率及bcl-2的表达,采用免疫组织化学法观察p53的表达。结果:孔圣枕中丹、脑复康均能降低血管性痴呆大鼠脑海马神经元凋亡率和bcl-2表达,提高p53表达,两组比较无显著性差异。结论:孔圣枕中丹能抑制神经元细胞凋亡,其机制可能与增强p53表达、降低bcl-2表达有关。  相似文献   
993.
Vascular air embolism (VAE) is a rare complication of percutaneous nephrolithotomy. Paradoxical air embolization resulting from VAE may be more likely to occur in patients with an atrial-septal defect, such as patent foramen ovale. Here, the case of a female patient with VAE that occurred during percutaneous nephrolithotomy is presented. Although the patient was diagnosed with patent foramen ovale, she recovered well without any severe paradoxical air embolization symptoms. To our knowledge, this is the first report of VAE with paradoxical air embolization that occurred in a patient with patent foramen ovale during percutaneous nephrolithotomy that was conducted without pneumopyelography.  相似文献   
994.
明代晚期,悠闲思隐与激昂抗愤,两种颇为极端的人生态度,同时流行于江南士人群体之中。究其深层原因,可以发现,实际上这是江南士人为应对日益严重的生存困境而作出的特殊选择。他们彷徨于理想和现实之间,既坚持固有的自尊、自傲,不愿舍弃兼济天下的志向,又不得不顺从环境,萌生独善其身的强烈愿望,期盼以一种清幽高雅、富有文化内涵、艺术化的生活方式来满足自己的文化优越感,抚慰内心的创痛。明清以来,随着政治环境和社会关系的急剧变动,知识分子群体的人格塑成更趋于多重性和复杂化,这或许可在晚明江南士人身上获得某些启示。  相似文献   
995.
Glioblastoma multiform (GBM) is a highly aggressive primary brain tumor. Exosomes derived from glioma cells under a hypoxic microenvironment play an important role in tumor biology including metastasis, angiogenesis and chemoresistance. However, the underlying mechanisms remain to be elucidated. In this study, we aimed to explore the role of connexin 43 on exosomal uptake and angiogenesis in glioma under hypoxia. U251 cells were exposed to 3% oxygen to achieve hypoxia, and the expression levels of HIF-1α and Cx43, involved in the colony formation and proliferation of cells were assessed. Exosomes were isolated by differential velocity centrifugation from U251 cells under normoxia and hypoxia (Nor-Exos and Hypo-Exos), respectively. Immunofluorescence staining, along with assays for CCK-8, tube formation and wound healing along with a transwell assay were conducted to profile exosomal uptake, proliferation, tube formation, migration and invasion of HUVECs, respectively. Our results revealed that Hypoxia significantly up-regulated the expression of HIF-1α in U251 cells as well as promoting proliferation and colony number. Hypoxia also increased the level of Cx43 in U251 cells and in the exosomes secreted. The uptake of Dio-stained Hypo-Exos by HUVECs was greater than that of Nor-Exos, and inhibition of Cx43 by 37,43gap27 or lenti-Cx43-shRNA efficiently prevented the uptake of Hypo-Exos by recipient endothelial cells. In addition, the proliferation and total loops of HUVECs were remarkably increased at 24 h, 48 h, and 10 h after Hypo-Exos, respectively. Notably, 37,43gap27, a specific Cx-mimetic peptide blocker of Cx37 and Cx43, efficiently alleviated Hypo-Exos-induced proliferation and tube formation by HUVECs. Finally, 37,43gap27 also significantly attenuated Hypo-Exos-induced migration and invasion of HUVECs. These findings demonstrate that exosomal Cx43 contributes to glioma angiogenesis mediated by Hypo-Exos, and suggests that exosomal Cx43 might serve as a potential therapeutic target for glioblastoma.  相似文献   
996.
手术治疗骶尾部藏毛窦的研究   总被引:2,自引:0,他引:2  
外科手术是骶尾部藏毛窦的主要治疗方法,手术方法可有多种。现就其国内当前常用手术的方法、优缺点、适应证和禁忌证及存在的问题作一探讨。  相似文献   
997.
Rationale:IgG4-related respiratory disease (IgG4-RRD) is a chronic autoimmune disease that affects the respiratory system and organs outside the respiratory system. This study explored the diagnosis and treatment of a case of IgG4-RRD with unilateral pleural effusion diagnosed using medical thoracoscopy, and provides an associated literature review. This report summarizes the clinical characteristics of IgG4-RRD involving the pleura to improve the diagnosis of this disease.Patient concerns:A 39-year-old man presented with a 2-week history of cough and chest tightness. Both physical examination and imaging supported the presence of left pleural effusion.Diagnosis:Medical electronic thoracoscopy was performed to obtain a pleural biopsy, which showed lymphoplasmacytic infiltration, 40 IgG4+ plasma cells per High Power Field (HPF) on microscopy, IgG4/IgG ratio >50%, phlebitis obliterans, and storiform fibrosis. The final diagnosis was IgG4-RRD.Interventions and outcomes:The patient was treated with methylprednisolone, after which his symptoms improved, and he was discharged. Oral hormone therapy was continued outside the hospital. After 4 months, the patient returned to the hospital and his condition had improved significantly.Lessons:Pleural involvement in IgG4-RRD is rare, and its diagnosis depends on pleural biopsy. Thoracoscopy usually reveals pleural thickening, pleural nodules, and milky white plaques.  相似文献   
998.
Rationale:This study describes an 8-year-old boy with a C2 fracture and dislocation with a left C2–C3 articular process interlocking and spinal cord injury who underwent open reduction and internal fixation using the posterior cervical approach and achieved satisfactory results.Patient concerns:An 8-year-old boy underwent an emergency transfer from a previous hospital after a car accident.Diagnoses:Axial fracture and dislocation with spinal cord injury (American Spinal Injury Association grade C), traumatic shock, brain contusion, intracranial hemorrhage, mandibular fracture, pulmonary contusion and hemorrhage, left vertebral artery stenosis, and multiple fractures throughout the body. Radiological examination revealed a fracture of the lower edge of the C2 vertebral body, fourth-degree anterior spondylolisthesis of the C2 vertebral body, interlocking of the left C2–C3 articular processes, widening of the C2–C3 vertebral space, and occlusion of the V1 and 2 segments of the left vertebral artery.Interventions:The boy was immediately intubated and transferred to the pediatric intensive care unit for rescue treatment. However, the reduction was unsuccessful with 2 weeks of cranial traction. Thus, an open reduction was performed under general anesthesia. One month after the surgery, the boy was discharged from the hospital on foot after rehabilitation treatment.Outcomes:The boy was discharged from the hospital 1 month after surgery. At the 8-month follow-up, a radiological examination showed that the corrected C2 vertebral body fracture and dislocation were satisfactorily reduced, and the spinal cord was adequately decompressed. The internal fixation position was also good, and the spinal sequence had recovered well. In summary, except for the muscle strength of the right upper limb, which was slightly worse, the other clinical symptoms were significantly improved.Lessons:In treating cervical fracture and dislocation with unilateral facet lock, the posterior open reduction of pedicle screw and lateral mass screw internal fixation achieved satisfactory results. Consequently, treating complex cervical spine injuries in children requires an accurate diagnosis and careful treatment strategy.  相似文献   
999.
The railway wheel is the key component of high-speed railway train. To assure the safety in service, higher requirements are put forward in this study for the composition, microstructure uniformity, and comprehensive properties of wheel materials. In this paper, the high throughput quantitative distribution characterization methods of composition, microstructure, inclusions and Vickers hardness of high-speed railway wheel materials based on the spark source original position analysis technique, high throughput scanning electron microscope (SEM) combined with image batch processing technology, and automatic two-dimensional quantitative distribution analysis technique of inclusions and micro hardness have been studied. The distribution trend of the content of nine elements, size and quantity of sulfides and oxides, ferrite area fraction, and Vickers hardness from the wheel tread surface to the radial depth of about 50 mm below the surface has been discussed. The influence of inclusions distribution on the element segregation and the effect of rim-chilling process with different water spraying angle on the distribution of microstructure and micro hardness have been investigated. It was found that unsynchronized cooling on both sides of the rim altered the phase behavior of ferrite and pearlite and obvious inhomogeneity distribution of ferrite appeared, which led to the asymmetrical Vickers hardness in areas near or away from the flange. Based on the quantitative characterization of area fraction and micro hardness on the same location of wheel rim, a statistical mapping relationship between ferrite area fraction and Vickers hardness was established.  相似文献   
1000.
目的 分析血药浓度监测(TDM)优化美罗培南治疗老年脓毒血症的临床疗效。方法 选择2021年1月至2022年2月我院收治的脓毒血症老年患者64例,随机分为对照组31例,观察组33例。对照组接受常规美罗培南治疗,观察组接受TDM优化美罗培南,对比治疗1周后两组病情变化、生化指标、肺功能、实验室指标与不良反应等。结果 治疗1周后,观察组APACHEⅡ评分/SOFA评分低于对照组(P<0.05),观察组肌酐、胆红素、AST、ALT、EVLW、PVPI下降(P<0.05),观察组白细胞、降钙素原、C-反应蛋白水平低于对照组(P<0.05),观察组美罗培南药物谷浓度与峰浓度高于对照组(P<0.05),观察组PK/PD参数最低抑菌浓度(MIC)为1、2、4时血清药物浓度高于MIC的时间(%T>MIC)优于对照组(P<0.05)。结论 65岁以上老年脓毒血症患者,实施TDM优化美罗培南治疗,可降低病情严重水平,调控机体生化指标、炎症指标,提高药物抗菌活性、药物有效浓度,改善患者肺功能,减少药物不良反应,具有临床意义。  相似文献   
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