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1.
PurposeTo evaluate the feasibility and accuracy of a radiation-free implantation of a thoracic aortic stent graft employing fiberoptic and electromagnetic tracking in an anthropomorphic phantom.Materials and MethodsAn anthropomorphic phantom was manufactured based on computed tomography (CT) angiography data from a patient. An aortic stent graft application system was equipped with a fiber Bragg gratings and 3 electromagnetic sensors. The stent graft was navigated in the phantom by 3 interventionalists using the tracking data generated by both technologies. One implantation procedure was performed. The technical success of the procedure was evaluated using digital subtraction angiography and CT angiography (before and after the intervention). Tracking accuracy was determined at various anatomical landmarks based on separately acquired fluoroscopic images. The mean/maximum errors were measured for the stent graft application system and the tip/end of the stent graft.ResultsThe procedure resulted in technical success with a mean error below 3 mm for the entire application system and <2 mm for the position of the tip of the stent graft. Navigation/implantation and handling of the device were rated sufficiently accurate and on par with comparable, routinely used stent graft application systems.ConclusionsThe study demonstrates successful stent graft implantation during a thoracic endovascular aortic repair procedure employing advanced guidance techniques and avoiding fluoroscopic imaging. This is an essential step in facilitating the implantation of stent grafts and reducing the health risks associated with ionizing radiation during endovascular procedures.  相似文献   
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Background: Rosacea is a chronic disease affecting the patients’ life quality negatively. Although various laser systems are used in the rosacea treatment, studies reporting efficacy and long-term continuity of benefit of laser therapies are scarce.

Objectives: We aimed to evaluate the efficacy, safety, continuity of benefit, and effect on life quality of pulsed dye laser (PDL) in the rosacea patients.

Methods: Fourteen rosacea patients treated with PDL were enrolled in the study. The number of treatment sessions were varied from one to four. The efficacy was evaluated by the physicians’ clinical assessment (PCA), patients’ self-assessment (PSA), and erythema and telengiectasia grading scores. Additionally, the patients were asked about the continuity of the benefit and improvement in their life qualities after the treatment.

Results: Both the erythema and telangiectasia scores were significantly improved after the treatment (p < 0.001). According to PCA, nine patients had a clinical improvement of >50%. According to PSA, 11 patients had good/excellent improvement. Moderate/significant benefit of treatment continued in 12 patients at the follow-up period (mean 21.64 ± 14.25 months). The life quality scores were significantly improved. No serious side effects were observed.

Conclusion: PDL has high and long-term efficacy in the treatment of rosacea with a good safety profile.  相似文献   

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Agri-environmental schemes (AES) aim to restore biodiversity and biodiversity-mediated ecosystem services in landscapes impoverished by modern agriculture. However, a systematic, empirical evaluation of different AES types across multiple taxa and functional groups is missing. Within one orthogonal design, we studied sown flowering AES types with different temporal continuity, size, and landscape context and used calcareous grasslands as seminatural reference habitat. We measured species richness of 12 taxonomic groups (vascular plants, cicadas, orthopterans, bees, butterflies, moths, hoverflies, flower visiting beetles, parasitoid wasps, carabid beetles, staphylinid beetles, and birds) representing 5 trophic levels. A total of 54,955 specimens were identified using traditional taxonomic methods, and bulk arthropod samples were identified through DNA metabarcoding, resulting in a total of 1,077 and 2,110 taxa, respectively. Species richness of most taxonomic groups, as well as multidiversity and richness of pollinators, increased with temporal continuity of AES types. Some groups responded to size and landscape context, but multidiversity and richness of pollinators and natural enemies were not affected. AES flowering fields supported different species assemblages than calcareous grasslands, but assemblages became more similar to those in seminatural grasslands with increasing temporal continuity. Our results indicate that AES flowering fields and seminatural grasslands function synergistically. Flowering fields support biodiversity even when they are relatively small and in landscapes with few remaining seminatural habitats. We therefore recommend a network of smaller, temporally continuous AES flowering fields of different ages, combined with permanent seminatural grasslands, to maximize benefits for biodiversity conservation and ecosystem service delivery in agricultural landscapes.

Human societies are facing a worldwide loss of biodiversity with alarming declines of insect diversity in temperate agricultural landscapes (1, 2). This loss of biodiversity is jeopardizing agricultural production as important ecosystem services ensuring crop yields are directly driven by biodiversity (3). Biodiversity, however, requires suitable habitats for species to persist, forage, nest, reproduce, and hibernate (4, 5). This challenge has been recognized and agri-environmental schemes (AES) have been introduced in the European Union and other regions to reverse biodiversity declines, to restore functional diversity, and to harness the benefits of ecosystem services, like pollination and pest control, in agricultural landscapes (68).An important component of AES to fulfill these goals is the establishing of habitats that provide limiting resources, such as food and shelter for a broad range of organisms. Typically, farmers are financially compensated on a per area basis, but the effectiveness of schemes is often unclear. Thus, compensations might not direct farmers’ decisions among different AES to the ecologically most meaningful ones (7). A variety of different habitats are created as AES, ranging from hedgerows to sown flower strips or flowering fields, with the latter being widely used due to their flexible applicability and public appreciation (4). Recent assessments, however, found that overall, European AES are not fulfilling their goals (6, 9). Particularly, the value of AES for securing biodiversity is under debate (10, 11). Beneficial effects previously reported focused on single taxonomic or trophic levels or ecosystem services and varied among study designs, taxa, or services assessed (1214). Conclusive multitaxa approaches assessing potential services and disservices in one design are missing (8). Furthermore, it is unclear how different properties of AES habitats (e.g., their temporal continuity or size) and varying landscape context affect biodiversity across multiple taxonomic groups.Temporal continuity is an important factor affecting biodiversity. Higher temporal continuity increases heterogeneity within a habitat and creates niches for more species (15, 16). Temporal continuity also enables weak dispersers and higher tropic levels to colonize a habitat, with the latter being dependent on established populations of lower trophic levels (15). In AES habitats, the influence and the effects of temporal continuity have so far been neglected. Newly established flowering fields were found to be more attractive to pollinators than older flowering fields, but pollination services in adjacent fields peak 2 y after initial sowing (14, 17). Older AES habitats could potentially also benefit rare and endangered species with specific habitat requirements, if species assemblages in AES habitats change toward those in permanent species-rich seminatural grasslands with time or increased temporal continuity (18).Apart from temporal continuity, size might be an important predictor for the conservation value of AES habitats. Increasing habitat size leads to an increased species richness as it is accompanied with the establishment of larger, more stable populations and allows higher trophic levels to persist (1921). It is unclear whether biodiversity in a landscape benefits more from few large habitats or a network of many small habitats (22, 23). Relationships between size and species richness might therefore be essential for the planning and strategic placement of AES habitats.Source habitats for biodiversity are needed in agricultural landscapes to build up local populations in newly established AES habitats from regional species pools (24). Seminatural habitats embedded in agricultural landscapes have been shown to support farmland diversity (25, 26), and thus AES habitats in complex landscapes with high proportions of seminatural habitats potentially host the highest diversity.Here, we investigate the effects of AES differing in temporal continuity, size, and surrounding landscape context over several years on multiple taxonomic groups within one study design. Different types of flowering fields are commonly established by farmers as part of AES to provide additional flower resources. These fields are sown with seed mixtures adapted to local soil properties and taken from regional species pools. After a certain timespan, often varying from 1 to 10 y, flowering fields are returned to crop production. The studied flowering fields differed in temporal continuity from: 1) Newly sown on arable land, over 2) refreshed (i.e., flower fields resown after 5 y) to 3) continuous, 6-y-old flowering fields. Species-rich calcareous grasslands were used as permanent control (Fig. 1 and Table 1). Calcareous grasslands are seminatural biodiversity hotspots in Europe and are preserved by low intensive mowing or grazing (27). We investigated species richness in these 4 AES types across 12 taxonomic groups belonging to 5 trophic levels, including pollinators (bees, butterflies, moths, flower visiting beetles, and hoverflies) and natural enemies (parasitoid wasps, carabid beetles, staphylinid beetles, and birds) as providers of important ecosystem services (3). Species were identified by classic taxonomic techniques (vascular plants, orthopterans, bees, butterflies, moths, flower visiting beetles, carabid beetles, staphylinid beetles, and birds) and DNA metabarcoding (cicadas, hoverflies, and parasitoid wasps). Repeated recordings of a subset of four taxonomic groups (plants, orthopterans, bees, and carabid beetles) within 2 y were performed to clarify whether short-term succession changed assemblages in newly established flowering fields toward those in seminatural calcareous grasslands. Apart from analyses for each taxonomic group, we performed a multidiversity analysis by calculating a diversity index across all taxa, pollinators, and natural enemies (28). Our study aims to judge which types of AES fulfill the goal of restoring biodiversity and ecosystem services in agricultural landscapes best, and should therefore be fostered. Such data are urgently needed to build the scientific basis for a successful transition of European Union and global policies to biodiversity-friendly and sustainable crop production.Open in a separate windowFig. 1.Study design on the landscape and site level. Biodiversity across 12 different taxonomic levels (from top to bottom: Vascular plants, orthopterans, cicadas, bees, butterflies, moths, flower visiting beetles, hoverflies, parasitoid wasps, carabid beetles, staphylinid beetles, birds) was recorded using a variety of classic methods (pan traps, pitfall traps, transect walks, light traps combined with taxonomic identification) as well as metabarcoding analyses (using samples collected with Malaise traps). The different types of flowering fields and calcareous grasslands were located along a gradient of temporal continuity (Table 1). All AES types covered independent gradients of seminatural habitat in the surrounding landscape and habitat size (purple, AES; yellow, arable land; light green, seminatural habitat; dark green, forest; gray, urban). Repeated recordings over 2 y were performed for vascular plants, orthopterans, bees, and carabid beetles to assess whether succession shifted assemblages in flowering fields toward those in seminatural calcareous grasslands.Table 1.Differences in temporal continuity
Habitat age, yLast soil disturbance, yTemporal continuityPrevious land useManagementVegetation
New sown flowering field11LowArable landNoneCustomary flower seed mixture; sown in the previous year
Refreshed sown flowering field>61Low–intermediateSown flowering field (5 y)NoneCustomary flower seed mixture; sown in the previous year
Continuous sown flowering field>6>6Intermediate–highSown flowering field (5 y)Mulching above ground once per year after JuneCustomary flower seed mixture sown >6 y ago; strongly shaped by succession
Calcareous grassland>>20>>20HighNAGrazing or mowing once per year after JuneSeminatural xerothermic grassland vegetation
Open in a separate windowDifferences in temporal continuity—resulting from habitat age and management—of the studied AES types in 2016 (first year of the study).We expected that: 1) Benefits of temporal habitat continuity differ among taxonomic groups, pollinators, and natural enemies; 2) temporal continuity and short-term succession alter species assemblages of sown flowering fields toward those in seminatural grasslands; and 3) multidiversity in sown flowering fields benefits most from the combination of temporal continuity, large habitat size, and high proportion of seminatural habitats in the landscape.  相似文献   
6.
目的探讨全身振动训练联合正弦交变电磁场对去卵巢骨质疏松大鼠骨密度、骨代谢、骨生物力学性能的影响。方法将100只大鼠随机分为切除卵巢组和对照组,分别进行卵巢切除术和假手术,大鼠进行6周恢复,恢复后将造模成功的切除卵巢大鼠随机分为模型组(MO组)、全身振动训练组(W组)、正弦交变电磁场组(S组)、全身振动训练+正弦交变电磁场组(WS组),对照组列为假手术组(SO组),进行为期16周干预,干预结束后对大鼠进行骨密度、骨代谢、骨生物力学性质的检测。结果16周干预完成后,MO组、S组大鼠体质量显著高于SO组、W组、WS组大鼠(P0. 05); W组、WS组、SO组大鼠骨密度指标、血清雌二醇浓度指标明显高于大鼠MO组(P0. 05); SO组大鼠血清雌二醇浓度指标明显高于S组、W组、WS组(P0. 05); M组大鼠血清OC、ALP浓度明显高于SO组、W组、S组、WS组大鼠(P0. 05);尿液DPD/Cre、Ca/Cre、P/Cre浓度方面,M组大鼠明显高于SO组、W组、S组、WS组大鼠(P0. 05)。SO组、W组、S组、WS组大鼠股骨最大载荷和弹性模型明显高于MO组大鼠(P0. 05)。SO组、W组、S组、WS组大鼠股骨断裂载荷组间无明显差异(P0. 05); SO组、W组、S组、WS组大鼠股骨弹性模量明显高于MO组大鼠(P0. 05)。SO组大鼠股骨弹性模量明显高于S组大鼠(P0. 05),但与W组、WS组大鼠没有明显差异(P0. 05)。L4椎体压缩试验,SO组、W组、S组、WS组大鼠股骨最大载荷和弹性模型明显高于MO组大鼠(P0. 05)。SO组大鼠高于S组、W组,差异有统计学意义(P0. 05),但与WS组大鼠没有明显差异(P0. 05)。结论全身振动训练、正弦交变电磁场、全身振动训练联合正弦交变电磁场3种干预方式施用于去卵巢骨质疏松大鼠均能提升骨密度、抑制骨吸收、平衡骨代谢、改善骨骼结构力学和材料力学性能。而全身振动训练联合正弦交变电磁场能的治疗效果优于单纯使用全身振动训练或正弦交变电磁场,在临床应用中有一定推广价值。  相似文献   
7.
目的介绍手术动力设备的电磁兼容测试方法,为多功能手术动力设备测试提供指引。方法通过对常见手术动力设备的不同功能逐一测试得出的结果进行比对,分析不同功能在同一检测项目中的差异。结果传导发射(Conduction Emission,CE)与负载引起的功率变化有关,辐射发射(Radiation Ernission,RE)与负载引起的功率变化无必然联系。静电放电(Electrostatic Discharge,ESD)与负载刀头到设备输入插口的插入损耗有关。结论可选择输入功率较大的负载进行CD和RE测试;电路原理不明确时,还可通过频谱仪预测判断后,选择出现最大幅值的负载进行RE测试;ESD测试选择插入损耗最小的负载测试;其余抗扰度项目可选取任一负载测试。  相似文献   
8.
BackgroundBone growth stimulators have been used as an adjunct to spinal fusion surgery in efforts to increase fusion rates.MethodsThe authors retrospectively reviewed the medical records of patients who underwent thoracolumbar fusion surgeries by a single surgeon. Patients were then separated into three groups; pulsed electromagnetic field stimulation (PEMF), combined magnetic field stimulation (CMF) or no stimulation (NS), and computed tomography radiographic results at least 1 year after surgery were compared (solid fusion, stable nonunion, and pseudarthrosis).ResultsA total of 60 patients were included; 16 (26.7%) used PEMF, 24 (40.0%) used CMF, and 20 (33.3%) had NS. There were no significant differences in patient demographics. There was no difference in the mean fusion levels (p = 0. 477). Solid fusion was achieved in 11/16 (68.8%) PEMF, 21/24 (87.5%) CMF, and 20/20 (100.0%) NS patients. Stable nonunion was displayed in 2/24 (8.3%) CMF, and zero PEMF and NS patients. There were 5/16 (31.3%) PEMF, 1/24 (4.2%) CMF, and zero NS patients demonstrating radiologic pseudarthrosis. There was a statistically significant difference between PEMF and CMF (p = 0.017) and between PEMF and NS (p = 0.006) groups. No statistical difference was found between CMF and NS (p = 1.000).ConclusionThis is the first study to compare PEMF and CMF bone growth stimulators in patients with degenerative pathologies who underwent thoracolumbar spinal fusions. Overall, the addition of these bone growth stimulators does not improve fusion outcomes, although CMF appears superior to PEMF.  相似文献   
9.
目的 了解某设备实验条件下不同位置脉冲X射线电离辐射水平,提出适当的防护建议。方法 采用热释光测量方法,分别在设备舱周围不同方向不同距离布放热释光剂量计,累积一定数量脉冲辐射后进行测量;采用电离室型X、γ剂量率仪(FJ-347A)实时测量工作状态下不同距离处电离辐射剂量率水平。依据《电离辐射防护与辐射源安全基本标准》(GB18871—2002)规定的职业照射人员和公众个人剂量限值提出不同工作位辐射防护建议。结果 热释光剂量计累计接收3 000个脉冲辐射,设备舱外壁0.01~8.98 mGy,顶部0.01~15.67 mGy,距外壁1~12 m之间0.01~2.18 mGy,工作位0 mGy。工作状态下,X射线剂量率仪测得距设备舱外侧壁1~20 m之间空气比释动能率范围0.26~16 mGy/h。结论 热释光剂量计、电离室型剂量率仪测量结果基本一致,说明两种方法均可用于脉冲X射线测量;工作状态下设备舱外近距离处辐射剂量率较高,可通过采取防护措施或者限制人员工作量以满足辐射防护要求。  相似文献   
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