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991.
目的探讨完全右半肝-左半肝劈离式肝移植在成人-成人或成人-大体重儿童中的临床应用。方法回顾2019年1月至12月间首都医科大学附属北京友谊医院完成的4例完全右半肝-左半肝劈离式肝移植的供受者临床资料,分析劈离式肝移植的手术方式、冷缺血时间、手术时间、术中输血量,观察患者术后并发症及相关预后。结果4例完全右半肝-左半肝劈离式肝移植的受者包括3例成人和1例大体重儿童(45 kg),年龄范围14~48岁,体重范围45~61 kg,终末期肝病模型评分分别为21、12、41和30分。移植物质量与受者体质量比为0.85%~1.35%。冷缺血时间457~650 min,手术时长460~575 min。4例患者移植术后早期肝功能恢复顺利,均未出现小肝综合征。随访至术后6个月,其中1例出现胆道吻合口漏,经内镜逆行胰胆管造影术治疗后治愈;1例出现胆道狭窄,经皮肝穿刺胆道引流术治疗后反复胆道感染;1例术后6个月死于肺部感染。结论在严格病例选择的情况下,可以开展完全右半肝-左半肝劈离式肝移植。  相似文献   
992.
BackgroundThe surgical treatment of moderate-advanced hallux rigidus is controversial. Cheilectomy is widely used but has recurrence rates of up to 30%. Dorsal oblique metatarsal osteotomy (DOO) has also shown good results, however, there is no study comparing outcomes of the DOO against cheilectomy.MethodsThis was a retrospective propensity score matched study based on registry data from a single tertiary institution. Between 2007 and 2017, all patients who had undergone dorsal cheilectomy or DOO for hallux rigidus were included. Patients with previous foot surgery, revision surgeries, and concomitant surgical procedures were excluded. Clinical outcomes, complication rates, revision rates and patient satisfaction were assessed at 2 years postoperatively.ResultsThere were 44 patients (34 cheilectomy, 10 DOO). After propensity score matching, 17 cheilectomy and all 10 DOO cases were selected for comparison. Patients in both groups had a significant improvement in visual analogue pain scores (VAS) and AOFAS 1st toe scores 2-years post-operatively (P < 0.001) with high levels of post-operative satisfaction (85.1%). Overall there were no statistically significant differences in post-operative scores, improvement in scores, complication rates, revision rates, and levels of patient satisfaction between groups.ConclusionsBoth the DOO and cheilectomy give similarly good outcomes for moderate-advanced hallux rigidus. Further studies are needed to elucidate differences in indications for each procedure.  相似文献   
993.
基于功能MRI(fMRI)的功能连接(FC)分析可用于研究大脑功能异常。全脑FC模式具有高度特异性,可如指纹般视为个体识别标记,进而诊断疾病并指导临床治疗。本文对全脑FC模式及其临床应用进展进行综述。  相似文献   
994.
目的开发公共卫生安全素养量表, 为我国公众的公共卫生安全素养测评提供适宜工具。方法通过理论构想、指标池构建、现场验证、题项缩减等步骤编制中国公共卫生安全素养初始量表, 转为"问卷星"电子问卷, 随机抽取4个省份共2 809名居民进行现场测试。利用经典测试理论(CTT)和项目反应理论(IRT)进行题项缩减。使用SPSS 23.0软件进行探索性因子分析(EFA)和单维性检验。使用R 4.1.1软件ltm和mirt包进行题项的心理测量学指标分析, 并绘制项目特征曲线(ICC)和信息函数曲线(IIC和TIF)。结果选用专家一致性系数最优的初始量表3, 共30个题项(B1~B30), 测试对象完成1个题项平均需9.8 s。根据CTT分析, 删除校正题项-总相关系数(CITC)<0.3及题项-维度相关系数(IDCC)<0.4的B2题项;删除CITC<0.3、IDCC<0.4及难度指数<0.2的B23题项;删除CITC<0.3及难度指数<0.2的B30题项。删除后量表总内部一致性信度(Cronbach’’sα)值为0.923。EFA提示删除14个因子载荷较小...  相似文献   
995.
目的 探索户外时间对小学生近视发生的影响,并评估其在不同年级学生中的差异,为预防近视相关政策制定提供依据。方法 本研究基于队列研究设计,在2019年调查了江苏、上海、福建、山西、河南、湖南、甘肃、重庆、广西9个省(自治区、直辖市)6 046名1~5年级小学生,现场对其近视情况进行检查,并在2020年对该群体再次进行随访,现场检测近视发生情况,并在2020年视力测量后一周内对近视相关行为进行问卷调查。采用χ2检验、Cochran-Armitage趋势检验比较组间差异,采用Cox比例风险回归模型检验户外时间与近视发生的关系。结果 在2020年,基线时为1~5年级的小学生近视发生率为27.5%,其中,1~2年级小学生近视发生率为23.0%,3~5年级小学生近视发生率为31.7%。控制协变量后,在1~2年级小学生中,平均每天户外时间≥1 h学生近视发生风险是平均每天户外时间<1 h学生的0.76倍(95%CI:0.62~0.93,P=0.008);而对于3~5年级小学生,平均每天户外时间≥3 h才对近视发生有显著保护作用,其近视发生风险是平均每天户外时间<3 h学生的0.75倍(95%CI:0.61~0.93,P=0.007)。结论 1~2年级小学生平均每天达到1 h户外时间可以降低近视发生率,而3~5年级小学生平均每天需达到3 h户外时间可能才会有效降低近视发生率。因此,针对不同年级小学生预防近视的户外时间推荐应有差异,年级越高,户外时间相应增加,降低其近视发生率。但同时,还要关注其他因素对近视的作用,采用综合手段防控近视的发生。  相似文献   
996.
ObjectiveTo assess and compare the performance of fluorine‐18‐labeled fluorodeoxyglucose positron emission tomography (18F‐FDG‐PET/ CT) and gallium‐68‐labeled tetraazacyclododecanetetraacetic acid‐DPhe1‐Tyr3‐octreotate (68Ga‐ DOTATATE) PET/CT in the targeted imaging of culprit tumors causing osteomalacia.MethodsThis was a clinical retrospective analysis. We analyzed 13 patients (five men, eight women; mean age, 49 years; range, 19–55 years) with suspicion of tumor‐induced osteomalacia (TIO) between March 2017 and October 2019. All patients underwent two functional imaging methods to locate the culprittumors. Studies were performed on a PET/CT scanner. The injection doses of 18F‐ FDG and 68Ga‐DOTATATE were 0.5mCi/kg and approximately 5.0mCi, respectively. In the two scans, the whole body was captured from head to toe 45 to 60 min after intravenous tracer injection. 68Ga‐DOTATATE PET/CT and 18F‐FDG PET/CT imaging results locate culprit tumors according to the following criteria: (i) abnormal foci uptake concentration was observed locally, and the uptake level was higher than the background level of the right lobe of the liver; (ii) combined CT showed or did not have obvious abnormal density changes; and (iii) non‐specific ingestion lesions due to fracture, arthritis, necrosis of femoral head are excluded. Compared with the results of pathological examination and clinical follow‐up, the sensitivity, specificity and accuracy of 68Ga‐DOTATATE PET/CT imaging and 18F‐FDG PET/CT imaging for TIO were analyzed.ResultsAll patients had symptoms of osteomalacia and hypophosphatemia. The lag time (symptoms to PET diagnosis) ranged from 2 to 12 years. There were eight cases of TIO patients and five cases of non‐TIO patients confirmed by surgery, pathology and follow‐up. Among the eight TIO patients, there were six cases (75.0%) of PMTs, one case (12.5%) of giant cell tumor, one case (12.5%) of hemangiopericutoma. Most (n = 6, 75.0%) of the confirmed tumors in our patient population were in the lower extremities, followed by craniofacial regions (n = 1, 12.5%), and torso (n = 1, 12.5%), respectively. Among the five non‐TIO patients, there were two cases of Fanconi syndrome, one case of rickets, and two cases of sporadic osteomalacia hypophosphorus. The culprit tumors could be located either in the bone (n = 5, 62.5%) or the soft tissue (n = 3, 37.5%). 18F‐FDG PET/CT was able to localize the tumor in six (6/13, 46.1%) patients. 68Ga‐DOTATATE PET/CT detected tumor in 8 (83.3%) of 13 patients. The sensitivity of 68Ga‐DOTATATE PET/CT imaging and 18F‐FDG PET/CT imaging in the evaluation of TIO in our patient population were 100% (8/8) vs 75% (6/8). The specificity of the two different methods was 80% (4/5). The overall accuracy was 92.3% (12/13) vs 76.9% (10/13).Conclusions 68Ga‐DOTATATE PET/CT is very effective in assessing hypophosphatemia patients with TIO typical symptoms compared with 18F‐FDG. Therefore, in clinically suspected cases of hypophosphatemic osteomalacia, 68Ga‐DOTATATE PET/CT should be preferred as an imaging modality investigation to avoid delay in the treatment of this disease.  相似文献   
997.

Based on a typical residential area, this paper studies the characteristics of pollutant concentration changes in two rainfall runoffs and the first flush effect of rainfall. In rainfall runoff, the concentrations of seven pollutants (CODMn, TN, DTN, NH3-N, TP, DTP, and PO43−) increased during the initial rainfall period and decreased in the later period. Rainfall causes the erosion of pollutants on the underlying surface so that water pollution begins when rainfall runoff occurs, and the pollution level drops over time. The seven pollutants all experience this first flush effect, of which, rainfall has the strongest scouring effect on NH3-N produced by domestic sewage. The significant excess of pollutants in rainfall runoff should be considered by management departments. In addition, the existence of the first flush effect makes it possible in theory to partially intercept rainfall runoff to control water pollution, thereby reducing the cost of pollution control.

  相似文献   
998.

Antibiotics, which can be used as veterinary drugs, are widely used in the prevention and treatment of infectious diseases for animals. However, overuse of antibiotics had caused serious problems on food contamination and human harm. For control such public issues, several of techniques have been in recent years. Ratiometric fluorescent (RF) technique, as one of the most promising strategies for quantitatively evaluated analytes, had been extensively developed for the readily measurements on the two different fluorescent emission intensities. In this review, the construction strategies for recent RF sensors will be mainly focused on. Meanwhile, the recent advances and new tendencies for detection of antibiotics based on RF technique shall be introduced. Finally, outlooks on the opportunities and challenges for quantitative fluorescence sensing on antibiotics will be summarized.

  相似文献   
999.
Bulletin of Environmental Contamination and Toxicology - For the immense requirement on agriculture and animal husbandry, application of pesticides and veterinary drugs had become a normal state in...  相似文献   
1000.
目的探讨我国长寿地区65岁及以上老年人氧化应激水平与高甘油三酯血症的关系。方法研究对象来源于2017-2018年“老年健康生物标志物队列研究”,最终将我国9个长寿地区2393名65岁及以上老年人群纳入研究。通过问卷调查和体格检测,收集调查对象的人口学特征、生活方式及健康状况等信息,同时采集调查对象的静脉血以检测丙二醛(MDA)、超氧化物歧化酶(SOD)及甘油三酯水平。采用限制性立方样条拟合多重线性回归模型分析MDA、SOD与甘油三酯的关联,采用广义线性混合效应模型分析氧化应激与高甘油三酯血症的关联。结果2393例调查对象年龄为(84.6±11.3)岁,最小65岁,最大112岁;男性1145名(47.9%);甘油三酯水平为(1.4±0.8)mmol/L,高甘油三酯血症检出率为9.99%(239名)。限制性立方样条拟合多重线性回归模型分析结果显示,MDA水平与甘油三酯水平呈线性关联;SOD水平与与甘油三酯水平呈非线性关联。广义线性混合效应模型分析结果显示,调整相关混杂因素后,MDA每升高1 nmol/ml,高甘油三酯血症检出风险增加[OR(95%CI)值为1.063(1.046,1.081)];SOD每升高1 U/ml,高甘油三酯血症检出风险降低[OR(95%CI)值分别为0.986(0.983,0.989)]。结论我国9个长寿地区65岁及以上老年人MDA和SOD水平与高甘油三酯血症发生风险有关联。  相似文献   
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