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21.
基于CASS的数字化宗地图自动绘制应用研究 总被引:1,自引:0,他引:1
针对过去传统的宗地图手工制作方法,利用南方CASS软件,探索地籍图形数据处理方法与应用,实现了宗地图的自动绘制,地籍表格及地籍统计信息的自动生成。 相似文献
22.
《Veterinary anaesthesia and analgesia》2022,49(1):118-125
ObjectiveTo describe an ultrasound-guided approach to the dorsal aspect of the quadratus lumborum muscle (D-QL) and to evaluate the spread of methylene blue dye in canine cadavers.Study designProspective, experimental anatomical study.AnimalsA total of 12 canine cadavers.MethodsThe ultrasonographic landmarks and injection technique for the D-QL approach were determined in two cadavers. Correct needle tip position was confirmed by computed tomography. Bilateral ultrasound-guided injections were performed in 10 cadavers between the QL muscle, the vertebral body and the ventrocaudal aspect of the transverse process of the first lumbar vertebra (L1) using two volumes of methylene blue: low volume (LV) 0.3 mL kg–1 or high volume (HV) 0.5 mL kg–1. Staining of the main thoracolumbar trunk, dorsal and ventral branches of the thoracic (T) and lumbar (L) spinal nerves, sympathetic trunk and epidural space were assessed following dissection. Data between groups were compared using Mann–Whitney U test. Data are presented as median (range).ResultsThe ventral branches of spinal nerves T12, T13, L1, L2, L3 and L4 were stained in 10%, 70%, 100%, 90%, 60%, 0% and 30%, 100%, 100%, 100%, 50% and 30% after LV and HV injections, respectively. Multisegmental spread of the sympathetic trunk was found on 3 (3–4) and 5 (3–6) vertebral spinal levels following LV and HV injections, respectively (p = 0.005). The T13 segment of the sympathetic trunk was stained after all HV injections. Epidural spread was found in 20% and 30% of LV and HV injections, respectively.Conclusions and clinical relevanceThe injection of HV versus LV dye using the D-QL approach provided more consistent staining of the thoracolumbar nerve structures which innervate the abdominal wall and viscera. Clinical studies are required to evaluate the analgesic efficacy of the D-QL block for abdominal procedures in dogs in vivo. 相似文献
23.
《Veterinary anaesthesia and analgesia》2022,49(2):203-209
ObjectivesTo describe an ultrasound-guided rectus sheath (RS) block technique in calves with injections of methylene blue and assess the extent of injectate spread and nerve staining in calf cadavers.Study designProspective, experimental, blinded cadaveric study.AnimalsA total of 16 calf cadavers weighing 30.7 ± 7.1 kg.MethodsUsing an ultrasound-guided, in-plane technique, each cadaver was injected with both a low (LV; 0.25 mL kg–1) and high (HV; 0.5 mL kg–1) volume of methylene blue dye. Volumes were randomly assigned to the left or right hemiabdomen. Ultrasound imaging was scored based on landmarks and needle visualization, and duration to perform injections were assessed. Dissections were performed immediately after injections. Staining of ventral branches of spinal nerves and the extent of dye spread were recorded by an anatomist unaware of treatment allocation.ResultsThe number of nerves stained in treatments LV and HV were 2.3 ± 1.7 and 4.4 ± 1.3, respectively (p = 0.0001). Branches of thoracic nerves T7–13 and lumbar nerves L1–2 were completely stained 6.3%, 6.3%, 31.3%, 62.5%, 56.3%, 37.5%, 31.3%, 6.3% and 0%, respectively, in treatment LV and 0%, 12.5%, 50%, 93.8%, 100%, 93.8%, 62.5%, 25% and 6.3%, respectively, in treatment HV. Ultrasound imaging was scored excellent in most cadavers and needle visualization deemed excellent in all injections. The mean duration to perform RS injections in both treatments was 2 (range, 1–6) minutes.Conclusions and clinical relevanceNerve staining results from treatment HV suggest that this RS injection technique could be clinically useful in ventral midline surgical procedures, including umbilical procedures, in calves. This study supports future clinical trials in calves. 相似文献
24.
《Veterinary anaesthesia and analgesia》2022,49(2):197-202
ObjectiveTo develop and describe an acoustic window to access and inject the retrobulbar region in donkey cadavers.Study designProspective cadaveric experimental study.AnimalsA total of 14 donkey cadaver heads.MethodsUltrasound landmarks for retrobulbar injection were identified by dissection of two cadavers. Ultrasound-guided retrobulbar injection of 3, 6 and 9 mL of contrast–lidocaine mixture (1:1) were evaluated using computed tomography (CT) in 12 cadavers for needle position and spread of injectate into the extraocular muscle cone.ResultsReal-time visualization of needle, extraocular muscle cone and optic nerve enabled successful intraconal instillation of injectate, as documented on CT images.Conclusions and clinical relevanceUltrasound-guided retrobulbar injections in cadaver donkeys provided adequate infiltration of the intraconal space. 相似文献
25.
本文介绍矩形区组方"RBS"设计的基本方法,单个"RBS"设计方差分析的数学模型,处理平均数效应,期望均方分解,遗传力及其遗传变异系数估值,并举例介绍"RBS"在树木育种中的应用。 相似文献
26.
EugeneOnyekweOnuorah 《林业研究》2002,13(3):183-190
本文调查了三种耐用木材(Afzelia africana J.E. Smith; Erythrophleum suaveolens (Guill & Perr.) Brenam. Syn. E guinensis G.Don. or Milicia excelsa (Welw) C.C. Berg. Syn. Chlorophora excelsa (Welw) Benth.)的心材提取物(在60%的甲醇中风干提取)和两种专用木材防腐剂(CCA和Penta)在暴露的土壤区组设计条件下,抑制三种木材腐朽菌(Coridopsis Polyzona Klotzch; Lenzites trabea; or Trametes cingulata Fr.)对见血封喉边材的侵袭的相对潜能,并测定其阈值。提取物和防腐剂的剂量分别是8.009、24.778、48.056、96.111、144.167 kg·m-3 ,样品的暴露处理时间与ASTM D1413-72规定的一致分别是14周和18周。结果显示:在阈值范围内,任何一种心材提取物或木材防腐剂在研究中对木材腐朽菌的抑制能力在0.01的显著水平下,差异显著。这些生物杀灭剂的相对功效是取决于真菌的种类。没有任何一种心材提取物或木材防腐剂(除在用最高的存留水平处理被侵袭的非洲毒箭木的条件下)对于被处理的木材能够授予"非常持久"等级。本土树种的心材提取物相对持久力的减少的可能原因是复杂的。在最高的存留量(144.167 kg·m-3)水平下,在0.05显著水平下每种心材提取物和任一种专用木材防腐剂(CCA和Penta)之间的功效差异不显著. 相似文献
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28.
园林道路平曲线的施工放线是一项比较繁难的工作.当园林绿地中的园路紧靠建筑物、水体等特殊环境,园路平曲线的交点和圆心都被遮挡或无法定位时,常规的园路平曲线放线方法有的不适用,有的则太复杂.针对这种特殊园路平曲线的放线工作情况,根据在工作中的探索,介绍了一种新颖的、简便的园路平曲线施工放线方法,并对此方法的操作步骤和适用范围及注意事项进行了详细的说明,旨在利用简单的工具准确高效地完成施工放线工作. 相似文献
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