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51.
ABSTRACT

Domestic chickens (Gallus gallus domesticus) were exposed to imidacloprid by gavage once daily for 7 consecutive days at 0, 0.03, 0.34, 3.42, 10.25, and 15.5 mg/kg/day (n = 20 per group; 5 6-week-old males, 5 6-week-old females, 5 9-week-old males, and 5 9-week-old females). The severity and duration of neurobehavioral abnormalities were recorded. Components of the innate and adaptive immune system were assessed with 7 standard functional assays. Temporary neurobehavioral abnormalities were observed in a dose-dependent manner, including muscle tremors, ataxia, and depressed mentation. Based upon mean clinical severity scores, the no observed adverse effect level (NOAEL) was 3.42 mg/kg/day, and the lowest observed adverse effect level (LOAEL) was 10.25 mg/kg/day. The effective dose value for the presence of any neurobehavioral abnormalities in 50% of the test group (ED50) was 4.62 ± 0.98 mg/kg/day. The ED50 for an adjusted score that included both severity and duration of neurobehavioral abnormalities was 11.24 ± 9.33 mg/kg/day. These ED50 values are equivalent to a 1 kg bird ingesting 29 or 70 imidacloprid treated soybean seeds respectively. Immunotoxicity was not documented, possible causes include the assays were insensitive, relevant immune functions were not examined, or imidacloprid is not immunotoxic at this dosing schedule in this species. Neurobehavioral abnormalities were a more sensitive indicator of the sublethal effects of imidacloprid than immunotoxicity.  相似文献   
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Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019  相似文献   
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罗田  程晓萍  熊燕 《卫生研究》2015,(2):252-256
目的探讨深圳市3家制造企业新招90后产线员工心理弹性、应对方式和心理健康间是否存在某种关系。方法在深圳市3家制造企业选取入职一周的新招90后产线员工,以其入职日期为单位进行整群抽样。应用心理弹性量表CDRISC、简易应对方式问卷SCSQ以及一般健康问卷GHQ-20三个量表分别测量其心理弹性、应对方式以及心理健康,并利用结构方程模型软件Amos 17.0进行路径分析。结果心理弹性与心理健康呈正相关关系(P<0.01);心理弹性和心理健康与积极应对呈正相关关系(P<0.01);心理弹性和心理健康与消极应对呈负相关关系(P<0.01);结构方程模型结果表明:心理弹性既可以直接影响心理健康,又可以通过积极应对和消极应对的中介作用间接影响心理健康。结论深圳市制造企业新招产线员工的心理弹性、应对方式与心理健康间存在线性相关关系,且心理弹性通过积极应对和消极应对对心理健康起着部分间接的作用。  相似文献   
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狼疮抗凝物是发生静脉血栓栓塞症的危险因素之一,在静脉血栓栓塞症患者中检测狼疮抗凝物,对治疗方案抉择和疗效预后判断等方面具有重要意义。目前尚无相关文献对狼疮抗凝物检测在静脉血栓栓塞症中的应用进展进行分析总结,为加深对此类患者的认识,更好地帮助临床医生对此类患者进行合理的诊治和管理,现就有关流行病学、检测注意事项及检测结果在静脉血栓栓塞症中的价值和相关治疗进行综述。  相似文献   
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Thoracic empyema in uremic patients on maintenance hemodialysis is a challenging situation. The clinical characteristics are rarely reported, and the surgical outcomes remain unclear. We report our experience with video-assisted thoracoscopic surgery in these patients during 10-year period of time. Between 2005 and 2015, we retrospectively reviewed the clinical characteristics, bacteriological studies, and thoracoscopic surgical results of 23 empyema patients undergoing maintenance hemodialysis. The mean patient age was 67.1 ± 12.9 years. All patients had additional preexisting systemic diseases. The mean duration of hemodialysis was 34.7 ± 25.8 months. The infections causing empyema were pneumonia in 11 (47.8%), blood stream infection in 8 (34.8%), and uremic pleuritis in 4 (17.4%). Among the 22 identified microorganisms, the most common pathogen was methicillin-resistant Staphylococcus aureus (31.8%). After thoracoscopic surgery, 8 patients (34.8%) required additional procedures for complications, including 2 patients who required repeated thoracoscopy for hemothorax and 6 (26.1%) patients who required open drainage for residual empyema. The mean hospital stay was 62.4 days, and 6 patients (26.1%) died in the hospital. Univariate and multivariate analyses revealed that maintenance hemodialysis longer than 5 years was a significant factor associated with in-hospital mortality (odds ratio: 14.8, 95% confidence interval 1.5–151.6; p < 0.0001). While surgical management of thoracic empyema in uremic patients undergoing maintenance hemodialysis is associated with high rates of complication and mortality, thoracoscopic surgery is feasible, especially for patients undergoing hemodialysis for less than 5 years.  相似文献   
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目的 探讨扶正消瘤颗粒对原发性肝癌血清中血管内皮生长因子(Vascular endothelial growth factor,VEGF)和缺氧诱导因子-1α(Hypoxia inducible factor-1α,HIF-1α)表达的影响及临床意义。方法 选择符合纳入标准的原发性肝癌患者66例,按1∶1随机分试验组和对照组。观察治疗过程中两组VEGF、HIF-1α水平的变化及对患者临床疗效指标的影响。结果 (1)在性别、年龄、合并乙型肝炎、Child-Pugh分级、AFP值、临床分期方面,试验组和对照组差异无统计学意义(P > 0.05)。(2)肝癌患者在治疗各时间节点的VEGF和HIF-1α表达水平呈线性正相关(r = 0.829,P < 0.001)。(3)VEGF浓度在经导管动脉化疗栓塞术(Transcatheter arterial chemoembolization,TACE)后3月降至术前水平(P > 0.05),HIF-1α在TACE后3月仍高于术前(P < 0.05)。(4)扶正消瘤颗粒可降低HIF-1α水平,下调VEGF的表达。(5)扶正消瘤颗粒可减少TACE序贯RFA治疗后的不良反应,提高患者的生活质量(P < 0.05)。(6)血清中VEGF水平与生活质量无明显相关性(P > 0.05,r = 0.251),HIF-1α水平与生活质量存在正相关性(P < 0.05,r = 0.450)。结论 扶正消瘤颗粒可明显改善TACE序贯RFA治疗后患者生活质量,降低HIF-1α水平,下调VEGF的表达,抑制肿瘤血管生成。  相似文献   
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