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61.
塔里木哈得油田多采用双台阶水平井钻井,主要难题为常规钻井技术井眼轨迹控制难,储层钻遇率低,钻井周期长。1m厚薄砂层油藏未能实现有效开发,东河砂岩水窜严重,油水分布混乱,影响后期开发效果。针对以上难题,在哈得油田钻井中引进旋转地质导向技术,与常规技术相比应用效果良好,平均储层钻遇率由55.43%提高至87.84%,平均单井日产量提高1倍,单井水平段节约钻井工期15d,成功地解决了薄油层钻井储层钻遇率低、钻井施工进度慢等难题。  相似文献   
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目的:观察数字化导向模板技术和3D软组织打印制作的个体化经皮穿刺中上胸椎椎弓根入路椎体成形术数字化导向模板的可行性。方法:回顾性选择20例中上胸椎骨折患者CT扫描数据。将数据输入3D打印机打印1∶1带软组织胸椎模型,并应用Mimics 15.0软件中3-matic模块设计中上胸椎体表椎弓根钉道及相应导向模板,3D打印机打印导向模板并固定带软组织胸椎模型后置入2.0 mm克氏针,CT扫描观察穿刺针的准确性,通过穿刺管注入骨水泥并用影像学进行验证,记录带软组织中上胸椎模型的打印时间、钉道设计及体表导向模板制作时间以及费用。结果:3D打印的一体化胸椎模型及数字化经皮穿刺中上胸椎椎弓根入路数字化导向模板能够满足中上胸椎经皮穿刺椎体成形术穿刺的要求,导板与皮肤表面贴合良好,骨水泥充盈良好。中上胸椎模型的打印时间及钉道设计、手术导向模板制作时间分别为(719.00±3.03) min,(12.30±1.01) min和(55.50±10.30) min,平均费用约为3 150元。结论:基于3D软组织打印技术的个性化经皮穿刺中上胸椎椎弓根导向模板可实现经皮穿刺的精确置入。  相似文献   
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《Clinical microbiology and infection》2022,28(8):1151.e9-1151.e16
ObjectivesTo evaluate whether simplification of antiretroviral treatment to dual therapy (DT) negatively impacts immune recovery (IR), immune activation and inflammation (IA/I), and HIV reservoir.MethodsAn open-label, single-centre, randomized controlled trial conducted in adult virologically suppressed HIV-infected patients on triple therapy (TT) with elvitegravir-cobicistat, emtricitabine and tenofovir alafenamide or dolutegravir (DTG), abacavir, and lamivudine (3TC). Participants were randomized to continue TT or switch to DTG, or darunavir/cobicistat (DRVc) plus 3TC. IR was assessed by CD4+/CD8+ ratio at 48 and 96 weeks. Changes in immune activation, proliferation, exhaustion, senescence, and apoptosis in CD4+ and CD8+ T cells, plasma sCD14, hsCRP, D-dimers, β2-microglobulin, IL-6, TNF-α and IP-10 levels, cell-associated HIV-DNA (CA-DNA), and unspliced HIV-RNA (usRNA) were also analysed.ResultsOne hundred and fifty-one participants were enrolled. Fourteen patients did not complete the follow up. In the ITT and PP analysis, the IR was similar between the treatment arms. In the ITT analysis, the median increase in CD4+/CD8+ ratio was 0.10, 0.04, and 0.07 at week 48, and 0.09, 0.05, and 0.08 at week 96 for TT, DTG/3TC, and DRVc/3TC, respectively. After adjusting for confounding factors, the slopes of changes in CD4+/CD8+ ratio over time were independent of treatment (F = 1.699; p = 0.436) and related only to baseline values (F = 756.871; p = 0.000). There were no differences in IA/I, CA-DNA, or usRNA between treatment arms.DiscussionBoth IR and IA/I, CA-DNA, and usRNA were similar in the three treatment groups, regardless of maintaining TT or simplifying to DTG/3TC or DRVc/3TC in virologically suppressed HIV-infected patients.  相似文献   
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BackgroundBeyond the detection of resistant HIV strains found in plasma samples, archival HIV-DNA in peripheral blood mononuclear cells (PBMCs) might represent a reservoir of additional resistance.ObjectiveTo characterize the HIV-1 resistance in PBMCs from patients with suppressed or low-level viremia (50–1000 copies/mL) and evaluate its added value compared to the resistance detected in previous plasma genotypic resistance tests (GRTs).Study designHIV-1 infected patients selected for treatment change despite low/undetectable viremia were tested. Number and type of primary resistance mutations (PRMs) detected in PBMCs were compared to those detected in previous plasma GRTs. Logistic regression assessed factors associated with presence of at least one PRM in PBMCs.Result468 patients with a PBMC GRT were analyzed; 149 of them had at least 2 plasma GRTs performed before PBMC genotyping. 42.3% of patients showed at least one PRM in PBMCs. The highest proportion of PRMs in PBMCs was observed for NRTI class (30.6%), followed by NNRTI (22.2%), PI (14.1%) and INI (4.9%). In 20.1% of patients, PRMs were detected only in PBMCs and not in any of the plasma GRT previously performed. By using multivariable analysis, a higher number of previous regimens, injecting drug-use route and a lower nadir CD4 were associated with significantly higher risk of detecting PRMs in PBMCs.ConclusionOur findings support the usage of PBMC GRT in addition to the current recommended plasma RNA test, especially when therapeutic and/or resistance information is not available.  相似文献   
67.
岗位评价又称职位评价,是指在岗位分析的基础上,按照一定的标准,对各个岗位的工作性质、责任要素、复杂因素、任职要素、工作环境等方面进行综合性的评价,确定岗位相对价值的过程[1].岗位评价方案通过对一系列报酬要素的排序或评分,衡量工作的相对价值,明确各个岗位的分类、级别的高低,保证对每个岗位的工作人员进行考核、晋升、奖罚等管理时,具有统一的标准,是现代人力资源管理理论中的重要内容.本文对国内外岗位评价方法及应用现状综述如下.  相似文献   
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《Radiography》2022,28(3):746-750
IntroductionIn response to advice from The National Institute for Health and Care Excellence (1) to reduce hospital visits during COVID-19, standard headrests were introduced for head and neck radiotherapy within Northern Centre for Cancer Care (NCCC). The standard headrest requires one mould room appointment compared to 3 appointments with customised headrests.MethodsTwo groups of 10 patients treated between December 2019 and June 2020 were retrospectively analysed by 1 observer. Groups were stratified according to age, sex and tumour site. One group had customised headrest and the other had standard headrest. Five hundred and forty seven cone beam computed tomography images were reviewed. A 6 Degree of Freedom match was performed then chin, shoulder and spine position were assessed using dosimetrist drawn structures. Structures out of the tolerance were recorded. A chi-squared test was used for statistical analysis.ResultsThe out of tolerance chin position count recorded was 21 for customised headrest and 36 for standard headrest, p-value 0.046. The shoulder position count was 13 for customised headrest and 77 for standard headrest p-value <0.001. The spine position count was 3 for CHR and 21 for standard headrest, p-value <0.001. This means the headrests compared are not equivalent in terms of set up reproducibility. Overall the standard headrest group had 10 set-up re-scans and no set up re-scans were recorded in the customised headrest group.ConclusionFewer hospital visits with SHR reduce patient exposure to COVID-19. However, CHR provided a more reliable level of immobilisation in this study.Implications for practiceThe radiotherapy service will be reviewed in line with these findings.  相似文献   
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We studied the role of European rabbits (Oryctolagus cuniculus) as a reservoir for Coxiella burnetii in the Iberian region. High individual and population seroprevalences observed in wild and farmed rabbits, evidence of systemic infections, and vaginal shedding support the reservoir role of the European rabbit for C. burnetii.  相似文献   
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