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1.
Vegetation water content (VWC) is the key input parameter for a soil moisture retrieval algorithm based on microwave remote sensing, and VWC uncertainty can limit the estimated accuracy of soil moisture. There has been little research on VWC algorithm development and validation in China, and the uncertainty of the VWC estimation method has not been well evaluated. Therefore, the aim of this study is to evaluate the uncertainty of the VWC estimation method used in the SMAP (Soil Moisture Active Passive) algorithm on three spatial scales (the point-scale, 30 m scale, and 1 km scale) for maize in northeast China. Results from three ground experimental datasets showed that the SMAP VWC estimation method was strongly biased with an average overestimation of 1.16 kg m?2,1.04 kg m?2, and 1.13 kg m?2 for the point-scale, 30 m scale, and 1 km scale respectively, and maximum bias occurred in the mid-stage of maize. Also, a new power relationship between NDVI (Normalized Difference Vegetation Index) and VWC was proposed for the 30 m scale based on Sentinel 2 NDVI and field VWC values from 2017 experiment, with respective R2 (coefficient of determination) and Root Mean Squared Error (RMSE) values of 0.80 and 0.67 kg m?2. The results confirmed that this power relationship was still suitable for VWC estimation at the 1 km scale, and it has smaller bias than the original SMAP VWC method. Future work will be carried out to evaluate the applicability of this VWC estimation method over a lager region. It is expected that it can improve the accuracy of soil moisture by providing high precision VWC input parameters.  相似文献   
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目的观察胆道结石合并糖尿病患者腹腔镜胆囊切除术(LC)后肠屏障功能的变化。方法将择期行LC的126例患者分为糖尿病组41例和非糖尿病组85例。术前及术后第1、3天,采用高效液相色谱法检测尿乳果糖与甘露醇比值(L/M),并采用酶联免疫吸附法(ELISA)检测尿脂肪酸结合蛋白(IFABP)及血清D-乳酸水平。结果2组患者均成功完成手术,无中转开放手术者。糖尿病组术后肛门排气时间长于非糖尿病组,差异有统计学意义(P<0.05)。糖尿病组术后第1、3天尿L/M、血清D-乳酸、尿IFABP均高于术前及非糖尿病组,差异均有统计学意义(P<0.05)。结论合并糖尿病的胆道结石患者行LC后会加重肠屏障功能障碍程度,术前控制好血糖水平或可降低肠道功能损伤的严重程度。  相似文献   
4.
Based on the physical randomization of completely randomized experiments, in a recent article in Statistics in Medicine, Rigdon and Hudgens propose two approaches to obtaining exact confidence intervals for the average causal effect on a binary outcome. They construct the first confidence interval by combining, with the Bonferroni adjustment, the prediction sets for treatment effects among treatment and control groups, and the second one by inverting a series of randomization tests. With sample size n, their second approach requires performing O(n4)randomization tests. We demonstrate that the physical randomization also justifies other ways to constructing exact confidence intervals that are more computationally efficient. By exploiting recent advances in hypergeometric confidence intervals and the stochastic order information of randomization tests, we propose approaches that either do not need to invoke Monte Carlo or require performing at most O(n2)randomization tests. We provide technical details and R code in the Supporting Information . Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
5.
改良超滤(MUF)技术作为心肺转流中节约用血的重要手段之一,具有浓缩血液、清除炎性介质、减轻组织水肿等优点,但随着微小化体外循环技术的应用,MUF在临床应用中的获益性和必要性开始受到各中心的重新审视。本文对近年来MUF的临床使用进展予以综述。  相似文献   
6.
Objective: To evaluate the effectiveness of a modified behavioral activation treatment (MBAT) intervention on reducing depressive symptoms in rural left-behind elderly.

Method: This is a randomized study registered in Chinese Clinical Trial Registry (ChiCTR-IOR-17011289). Eighty rural left-behind elderly people who had a Geriatric Depression Scale (GDS) score between 11 and 25 were randomly assigned to the intervention (n?=?40) and control group (n?=?40). The intervention group received both MBAT and regular treatment for 8 weeks while the control group received regular treatment. Both groups were assessed with the GDS, Beck Anxiety Inventory (BAI), and Oxford Happiness Questionnaire (OHQ) at baseline, immediately post-intervention, and at 3 months post-intervention.

Results: There were a total of 73 participants that completed the intervention. The scores of GDS and BAI decreased significantly, but the scores of OHQ increased significantly in the intervention group after 8 sessions of MBAT (P?<?.01). The reduction in depression symptoms after the intervention was maintained at the 3-month follow-up. Significant differences in GDS, BAI, and OHQ scores were observed between the intervention group and the control group (P?<?.01).

Conclusion: MBAT produced a significantly greater reduction in depressive symptoms than regular care in rural left-behind elderly.

Clinical or methodological significance of this article: A modified behavioral activation (BA) psychotherapy can significantly reduce the recurrence and seriousness of depression symptoms in the left-behind elderly with mild to moderate depression. This study also suggests that further study of the MBAT as an intervention will provide a direction for the management of mental health in rural left-behind elders.  相似文献   

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背景与目的:结直肠癌(colorectal cancer,CRC)为世界第三常见恶性肿瘤,近年来研究者认为白细胞介素(interleukin,IL)-35和(或)IL-37与CRC的发展有关,但其作用机制尚未阐明。探究IL-35和IL-37在CRC发展中的作用及其可能的机制,分析IL-35和IL-37与CRC患者预后的相关性。方法:收集2013年—2017年在上海交通大学医学院附属同仁医院接受治疗的191例CRC患者手术病理蜡块的肿瘤组织,与其匹配的非癌组织是来源于同一患者的肠癌手术切缘蜡块组织。应用免疫组织化学(immunohistochemistry,IHC)染色法将CRC患者的癌组织与非癌组织染色,并运用Image-Pro Plus将IHC染色阳性部分定量分析,结合随访结果,探讨癌组织与非癌组织中IL-35和IL-37的表达水平与CRC临床病理学特征及预后的相关性。结果:与非癌组织相比,CRC组织中IL-35的表达量减少了50%(P<0.000 1)。CRC组织中IL-37的表达量与非癌组织相比增加了40%(P=0.012)。多因素生存分析显示,癌组织中IL-35(HR=0.39;95% CI:0.16~0.97;P=0.04)的表达水平是CRC患者术后生存的独立预测指标。结论:IL-35和IL-37蛋白的表达水平可能与CRC的发展有关,IL-35的表达水平可能是CRC患者术后生存的独立预测指标。  相似文献   
9.
In a biological microenvironment, free fatty acids (FFA) as ubiquitous biological molecules might interact with nanoparticles (NPs) and consequently change the toxicological responses. However, whether the chemical structures of FFA could influence their interactions with NPs remain unknown. This study investigated the interactions between ZnO NPs and saturated or unsaturated FFA (complexed to BSA), namely stearic acid (SA, C18:0), oleic acid (OA, C18:1), and α-linolenic acid (ALA, C18:3). It was shown that BSA, SA, OA, and ALA increased the atomic force microscope (AFM) heights as well the polydispersity index (PDI) of ZnO NPs. BSA modestly protected THP-1 macrophages from ZnO NP exposure, whereas OA and ALA led to relatively less cyto-protective effects of BSA. Moreover, only co-exposure to ZnO NPs and SA significantly promoted the release of interleukin-8. BSA, SA, OA, and ALA equally changed intracellular ROS and Zn ions associated with ZnO exposure, but co-exposure to ZnO NPs and OA/ALA particularly activated the expression of endoplasmic reticulum stress-apoptosis genes. In combination, these results showed that FFA could influence the colloidal aspects and toxicological signaling pathway of ZnO NPs, which is dependent on the number of unsaturated bonds of FFA.  相似文献   
10.
目的 探讨接受新辅助放化疗的局部晚期食管鳞癌患者新辅助放疗剂量与病理完全缓解(pCR)的关系。方法 收集2017-2019年间在四川大学华西医院肿瘤中心经病理确诊为食管鳞癌并接受新辅助放化疗和手术的 116例局部晚期患者临床资料。116例患者中 40~45Gy组 80例,≥45Gy组 36例,分析两组术后pCR率。结果 全组患者的pCR率为38.8%(45/116),40~45Gy组与≥45Gy组的pCR率分别为44%(35/80)和28%(10/36)(P=0.105)。结论 术前新辅助采用较高的放疗剂量不增加局部晚期食管鳞癌的pCR率,有必要进行前瞻性的临床研究确定合适的新辅助放疗剂量。  相似文献   
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