可调弯鞘在回收困难的伞形下腔静脉滤器取出术中的应用

目的探讨可调弯鞘在回收困难的伞形下腔静脉滤器取出术中的应用价值。方法收集2021年7月至2023年2月于南京中医药大学附属无锡医院就诊的24例滤器回收困难患者临床资料,均采用可调弯鞘进行滤器回收,分析所有患者的手术成功率,观察下腔静脉血流通畅情况、管壁情况、造影剂外溢或滞留情况、滤器情况、相关并发症发生情况。结果23例患者手术成功,1例因患有阿尔茨海默病,术中不能配合而放弃手术。回收滤器均结构完整、无折断,无变形,滤器取出后行下腔静脉造影均未发现造影剂滞留或外渗。手术时间25~120 min,平均58 min,未明显增加手术时间及费用,无相关并发症发生。结论应用可调弯鞘可以显著提高回收钩贴壁的下腔静脉滤器回收成功率,安全、有效,具有一定的临床应用价值。

基于自适应模型预测的物伞系统速度跟踪控制

针对空投易碎易爆物品无速度跟踪及速度波动大的问题,提出自适应模型预测控制(model predictive control,MPC)方法对物伞系统速度进行控制跟踪。以线性离散化物伞系统动力学模型为基础,通过迭代法构建速度跟踪预测模型,依据实际需求设计目标函数及约束条件,在自适应MPC控制器内进行优化求解;引入卡尔曼滤波作为状态估计器,让系统具备对自身状态量变化的感知,提供估计状态量给控制器,实现系统整体反馈校正。开展无风条件和有风条件下自适应MPC控制的物伞系统速度跟踪性能研究,结果表明,此控制方法能够实现对期望速度的良好跟踪;在随机扰动下进行物伞系统速度跟踪控制鲁棒性研究,对比分析了自适应MPC方法和PID控制方法的速度跟踪性能,结果表明,自适应MPC控制的物伞系统速度振荡小于PID控制,其具有较强的抗非线性扰动能力,为实现物伞系统速度控制提供了新方法。

超声影像对置入伞形滤器治疗下肢深静脉血栓的疗效评估

目的:探讨超声影像对置入伞形滤器治疗下肢深静脉血栓疗效的评估价值。方法:对2018年10月至2022年10月于北京大学第三医院延庆医院收治的85例下肢深静脉血栓患者的临床资料进行回顾性分析,依据患者的治疗效果和临床症状改善情况将其分为治愈组(38例)、显效组(27例)和有效组(20例),所有患者均接受置入伞形滤器以及患侧腘静脉穿刺,连接溶栓导管与微量泵,将尿激酶泵入。所有患者接受超声造影检查,于术后1、3及5d经溶栓导管注入经过稀释的超声造影剂,分析超声造影的灌注情况,采用超声造影定量分析软件获取时间-强度曲线(TIC)、达峰时间(TTP)、峰值强度(DPI)、曲线上升支斜率(C)等。对比患者术后1、3和5d各项定量参数。结果:治疗后患者的管壁内膜缩小(82例)、血管压缩性较好(58例)以及管腔内回声清晰(61例)相较于治疗前有明显改善,差异均有统计学意义(χ^(2)=52.407、61.917、74.518,P<0.05);治疗总有效率为100%;治愈组、显效组及有效组患者术后5d的TTP、DPI及C分别为治愈组(14.02±5.41)s、(-10.77±3.22)s、(4.91±1.33)dB/s,显效组(17.95±7.41)s、(-13.87±4.01)s、(4.11±1.20)dB/s与术后1d比较差异均有统计学意义(治愈组:t=11.615、-22.122、-16.112,P<0.001;显效组:t=8.820、-13.073、-10.804,P<0.001;有效组:t=6.791、-7.725、t-6.633,P<0.05);术后3d 3组患者DPI、C比术后1d高,而TTP则比术后1d低,差异均有统计学意义(治愈组:t=-18.857、-12.387、-7.254、-7.435,P<0.001;有效组:t=-5.076、-6.919,P<0.05);术后5d治愈组和显效组患者的DPI、C均比有效组高,差异均有统计学意义(t_(DPI)=12.219、7.457,t_(C)=4.826、2.530,P<0.05)。结论:对下肢深静脉血栓可选用置入伞形滤器后置管溶栓治疗的方法,置入的伞形滤器可对血栓进行有效拦截,并可在静脉内长时间留置。还可在下腔静脉造影剂时观察灌注情况及直观反映下肢深静脉患者经置入伞形滤器后置管溶栓治疗后静脉的再通情况。

Umbrella with Ultraviolet Radiation Protection

Background: Ultraviolet radiation (UVR) causes harm to the eye and skin in human. There are many ways to protect one from UVR. Umbrella is widely used due to its convenience as well as its ability to protect one from rain. However, there are limited numbers of studies on UVR protection of different types of umbrellas. Objective of study: To determine UVR protection efficacy of different umbrella designs. Methods: The experimental study was performed on five sunny days. Six manikins were placed in an open area, five of which were equipped with five different types of black canopy umbrellas. One manikin was placed without an umbrella as a control sample. Polysulfone film badges were attached in six different areas in each manikin for measuring the UVR from 10 am - 3 pm Results: All types of umbrellas provides 64.5% - 92.3% UVR photo protection efficacy. An umbrella with UV-filter coating on the inner surface provides maximum UVR photo protection efficacy. However, UVR proto protection efficacies of an umbrella with UV-filter coating on the inner surface and one with UV-filter coating on the outer surface and one without UV-filter coating are not statistically significant (p-value = 0.37). Umbrellas with a diameter of 122 cm and 152 cm provide comparable UVR photo protection efficacy while an umbrella with a diameter of 112 cm provides the least UVR photo protection efficacy. However, UVR photo protection efficacies of umbrellas with different diameter are not statistically significant (p-value = 0.36). The area of the body that received the most UVR photo protection is the forehead which is statistically significant when compared with other areas of the body (p-value < 0.001). The areas of the body that received the least UVR photo protection are the left ear and the back of the neck, which are statistically significant when compared with other areas of the body (p-value < 0.001). Conclusion: All types of umbrellas provide UVR photo protection efficacy. The study shows that umbrellas with different canvas material including both the UV-filter coating and different diameter of umbrellas could effectively protect the user from UVR without significant group difference in this study.

新型伞状下腔静脉过滤网在骨科复杂创伤中的初步应用

目的:探讨新型伞状下腔静脉滤网在骨科复杂创伤伴有下肢深静脉急性血栓形成患者中的应用价值。方法:对已发现的下肢深静脉血栓形成的骨科复杂创伤患者30例,术前置入新型伞状下腔静脉滤网后再行手术治疗,术后随访评价患者静脉血栓的情况。结果:30例发现下肢深静脉血栓的骨科复杂创伤患者接受了下腔静脉滤网植入术,术中顺利,未见严重并发症,骨科手术时,无一例患者发生肺栓塞,术后患者功能恢复满意。经随访,10例患者静脉血栓缩小,15例消失,5例未见明显变化。滤网周围均未见血栓形成。结论:新型伞状下腔静脉滤网能有效防止下肢深静脉栓塞引起的严重并发症,提高骨科手术的安全性。

对地热井成井工艺技术的探讨与认识

自1998年以来,通过钻凿的40多眼地热井(井深从2000m至4080m不等),在不断的突破创新中,摸索出了一套快速独特的成井工艺,为企业节约了成本,创造了效益,为陕西关中地区地热新能源开发做出了积极贡献。本文是作者十余年来组织和参与地热井施工的经验总结。提出了裸眼滤水管成井、联体伞式止水器止水、泵室段与技术套管穿袖封固连接以及高压空气压缩机负压洗井四大技术,为建立和完善具有本区特色的地热井成井工艺技术系列提供了重要依据,对今后该区及同类地区施工地热井将起到借鉴作用。