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The combined prognostic value of pretreatment neutrophil-to-lymphocyte ratio,lymphocyte-to-monocyte ratio,and platelet-to-lymphocyte ratio in stage IE/IIE extranodal natural killer/T-cell lymphoma 预览
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作者 Xiaoying Quan 《肿瘤学与转化医学:英文版》 2019年第3期137-146,共10页
Objective This study aimed to explore the combined prognostic value of pretreatment neutrophil-tolymphocyte ratio(NLR), lymphocyte-to-monocyte ratio(LMR), and platelet-to-lymphocyte ratio(PLR) in newly diagnosed IE/II... Objective This study aimed to explore the combined prognostic value of pretreatment neutrophil-tolymphocyte ratio(NLR), lymphocyte-to-monocyte ratio(LMR), and platelet-to-lymphocyte ratio(PLR) in newly diagnosed IE/IIE extranodal natural killer/T-cell lymphoma(ENKTL) treated with a P-Gemox regimen combined with radiotherapy or radiotherapy alone.Methods A total of 132 patients from 2009 to 2017 at the Sichuan Cancer Hospital were enrolled in the study. The cutoff values of NLR, LMR, and PLR using overall survival(OS) rate as an endpoint were obtained by the receiver operating curve. Results The cutoff value of NLR was 3.5. Patients with high NLR had significantly shorter progressionfree survival(PFS)(P < 0.001) and OS(P < 0.001) than those with low NLR. Similarly, the cutoff value of LMR was 3.0. The high LMR group had significantly longer PFS(P=0.001) and OS(P < 0.001) than the low LMR group. Similarly, the cutoff value of PLR was 191.7. The high PLR group was significantly associated with poor PFS(P < 0.001) and OS(P < 0.001) than the low PLR group. Furthermore, combining NLR, LMR, and PLR to build a new model to stratify patients into low-, intermediate-, intermediate-high-, and high-risk groups, there were also significant differences in PFS(P < 0.001) and OS(P < 0.001). The univariate analysis showed that presenting B symptoms, stage IIE, local tumor invasion, Eastern Cooperative Oncology Group score ≥ 2, elevated lactate dehydrogenase level, elevated NLR, decreased LMR, and elevated PLR were significantly associated with poor survival. The multivariate analysis demonstrated that PLR was an independent prognostic factor for both PFS(hazard ratio [HR]= 2.073, 95% confidence interval [CI]= 1.080–3.981, P = 0.028) and OS(HR = 2.127, 95% CI = 1.102–4.107, P = 0.025).Conclusion Elevated pretreatment PLR was a novel simple predictor of poor survival in patients with stage IE/IIE ENKTL. Combining NLR, LMR, and PLR could provide additional stratification. 展开更多
关键词 EXTRANODAL natural killer/T-cell neutrophil-to-lymphocyte RATIO lymphocyte-to-monocyte RATIO platelet-to-lymphocyte RATIO prognosis
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A novel kind of multiple steady states characteristics in the dividing wall column
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作者 Erwei Song Zengxi Li Erqiang Wang 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第4期869-876,共8页
In this article, one kind of multiple steady states(MSS) phenomenon was investigated for a dividing wall column(DWC). The four-section model constructed in Aspen Plus was employed to simulate two DWC cases: mixture of... In this article, one kind of multiple steady states(MSS) phenomenon was investigated for a dividing wall column(DWC). The four-section model constructed in Aspen Plus was employed to simulate two DWC cases: mixture of n-hexane, n-heptane and n-octane;system of methanol, ethanol and n-propanol. It can be seen that there is a range of vapor split ratio in which multiple solutions of reflux ratio exist for fixed DWC configuration with the same feed and product streams. The width and the curve shapes of the MSS region, and the number of solutions change with the liquid split ratio. This MSS phenomenon was further explained using the component recovery around the prefractionator and the component recycling flow inside the DWC. This MSS phenomenon is helpful for DWC design by knowing the probable existence of multiple solutions in advance. 展开更多
关键词 Dividing wall COLUMN Multiple STEADY STATES Vapor SPLIT RATIO Liquid SPLIT RATIO RECYCLING flow
Analysis of Similarities of Different Species of Boenninghausenia Plants by Common and Variant Peak Ratios Dual Indicator Sequence Method 预览
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作者 Nannan LONG Risha WEIZE +3 位作者 Hairong ZH Xiaoxia CAI Yuan LIU Ying LI 《药用植物研究(英文版)》 2019年第2期73-78,84共7页
[Objectives] To analyze the similarities of Boenninghausenia sessilicarpa Levl. and Boenninghausenia albiflora(Hook.) Meiss by the common and variant peak ratio dual indicator sequence method.[Methods] Four different ... [Objectives] To analyze the similarities of Boenninghausenia sessilicarpa Levl. and Boenninghausenia albiflora(Hook.) Meiss by the common and variant peak ratio dual indicator sequence method.[Methods] Four different solvents(petroleum ether, chloroform, ethyl acetate and methanol) were used to extract the chemical components of different polar regions of B. sessilicarpa and B. albiflora. UV-visible spectrophotometry(second derivative method) was used to collect the fingerprints of different solvent extracts, and common and variant peak peak ratios were analyzed for the absorption peak data.[Results] The common peak ratio and variant peak ratio data of ground parts of B. albiflora and B. sessilicarpa was S2∶S5(46.2(54.2, 62.5)), compared with the data of other groups, the common peak ratio was the largest, thus the components of ground parts of B. albiflora and B. sessilicarpa were closest and had the largest similarities;the common peak ratio and variant peak ratio data of the components extracted by chloroform from B. albiflora and B. sessilicarpa was Y2∶Y6(54.2(38.5, 46.2)), compared with the data of other groups, the variant peak ratio was the smallest, thus, the chemical components near the chloroform polarity of two kinds of medicinal materials had the largest similarities and smallest differences.[Conclusions] This method is simple and easy to operate, and the ultraviolet fingerprint data of four different polar organic solvent extracts are used for comprehensive analysis, and the results have high specificity and high accuracy. Besides, there are certain similarities and also differences between the chemical components of B. sessilicarpa and B. albiflora. It is expected to provide a new evaluation method for the variety quality of B. sessilicarpa and B. albiflora. 展开更多
关键词 Boenninghausenia albiflora (Hook.) Meiss Boenninghausenia sessilicarpa Levl. Ultraviolet FINGERPRINT COMMON PEAK RATIO VARIANT PEAK RATIO
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The relationship of blood cell-associated inflammatory indices and diabetic retinopathy: a Meta-analysis and systematic review
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作者 Wen-Juan Luo Wen-Fang Zhang 《国际眼科杂志:英文版》 SCIE CAS 2019年第2期312-323,共12页
AIM:To explore the correlation between several blood cell-associated inflammatory indices including mean platelet volume(MPV), platelet distribution width(PDW), neutrophil to lymphocyte ratio(NLR) and platelet-lymphoc... AIM:To explore the correlation between several blood cell-associated inflammatory indices including mean platelet volume(MPV), platelet distribution width(PDW), neutrophil to lymphocyte ratio(NLR) and platelet-lymphocyte ratio(PLR), and the presence and severity of diabetic retinopathy(DR). METHODS:We searched for eligible studies from PubMed, EMBASE, Web of Science and CNKI up to December 13, 2017. Standardized mean difference(SMD) calculated with confidence interval(CI) of 95% was used to estimate the values of those indices. RESULTS:A total of 31 studies were included in the present Meta-analysis. As compared with type 2 diabetes mellitus(T2 DM) patients without DR, the values of MPV, PDW, NLR, and PLR were higher in patients with DR(SMD=0.67;95%CI:0.36 to 0.98;SMD=0.51;95%CI:0.27 to 0.75;SMD=0.77;95%CI:0.49 to 1.05 and SMD=1.18;95%CI:0.07 to 2.28). Additionally, it was also observed that MPV was closely correlated with the severity of DR. CONCLUSION:MPV, PDW, NLR, and PLR could be recommended as diagnostic biomarkers for DR, and MPV could be applied to assess the severity of DR. 展开更多
关键词 mean PLATELET volume PLATELET distribution width NEUTROPHIL to LYMPHOCYTE RATIO platelet-lymphocyte RATIO diabetic RETINOPATHY
GNSS多天线基线网单历元模糊度同步解算法 预览
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作者 汤佳明 柴艳菊 +1 位作者 闻德保 欧吉坤 《大地测量与地球动力学》 CSCD 北大核心 2019年第3期262-268,共7页
提出多天线基线网单历元模糊度同步解算法,其具体实现步骤为:1)根据宽巷组合模糊度易于固定的优点,采用附加已知基线长度约束法同步解算各基线的宽巷模糊度,得到dm~cm级精度的近似基线分量;2)将解算得到的各近似基线分量作为约束,同步... 提出多天线基线网单历元模糊度同步解算法,其具体实现步骤为:1)根据宽巷组合模糊度易于固定的优点,采用附加已知基线长度约束法同步解算各基线的宽巷模糊度,得到dm~cm级精度的近似基线分量;2)将解算得到的各近似基线分量作为约束,同步解算各基线的基频模糊度,以获取mm级精度的基线矢量。该方法的关键在于检验各历元宽巷模糊度解算的正确性,以获取可靠的近似基线分量,为解算各基线的基频模糊度提供准确的基线先验信息。由于动态情况下各历元观测信息比较少,单纯依赖ratio检验不可靠,提出结合基线误差、单位权中误差、基线网模糊度闭合环及ratio值等对多组宽巷模糊度进行检验,避免ratio值设置不当导致模糊度检验中发生纳伪和弃真问题。实测数据结果证明,该处理方法使得模糊度解算的成功率提高1%~2%,可以获取移动平台更丰富的导航信息,提高其服务能力。 展开更多
关键词 多天线基线网 宽巷基线分量约束 ratio检验 模糊度闭合环检验
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Characterization of CANON reactor performance and microbial community shifts with elevated COD/N ratios under a continuous aeration mode
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作者 Yao Zhang Yayi Wang +2 位作者 Yuan Yan Haicheng Han Min Wu 《中国环境科学与工程前沿:英文版》 SCIE EI CAS CSCD 2019年第1期73-85,共13页
The effects of increasing COD/N on nitrogen removal performance and microbial structure were investigated in a SBR adopting a completely autotrophic nitrogen removal over nitrite process with a continuous aeration mod... The effects of increasing COD/N on nitrogen removal performance and microbial structure were investigated in a SBR adopting a completely autotrophic nitrogen removal over nitrite process with a continuous aeration mode (DO at approximately 0.15-0.2 mg/L). As the COD/N increased from 0.1 to W0.59, the nitrogen removal efficiency QMRE) increased from 88.7% to 95.5%;while at COD/N ratios of 0.59-0.82, the NRE remained at 90.7%-95.5%. As the COD/N increased from 0.82 to 1.07, the NRE decreased continuously until reaching 60.1%. Nitrosomonas sp.(AOB) and Candidatus Jet tenia (anammox bacteria) were the main functional genera in the SBR. As the COD/N increased from 0.10 to 1.07, the relative abundance of Nitrosomonas decreased from 13.4% to 2.0%, while that of Candidatus Jettenia decreased from 35% to 9.9% with COD/N < 0.82 then increased to 45.4% at a COD/N of 1.07. Aerobic heterotrophic bacteria outcompeted AOB at high COD loadings (650 mg/L) because of oxygen competition, which ultimately led to deteriorated nitrogen removal pertormance. 展开更多
关键词 CANON process COD/N ratio Anammox Ammonia oxidizing BACTERIA Aerobic HETEROTROPHIC BACTERIA
浅谈能力验证活动实例应用 预览
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作者 高吉 《中国质量与标准导报》 2019年第6期49-51,共3页
能力验证活动旨在了解参加检验实验室的整体水平和技术能力,提高该领域检测数据的有效性,能力验证活动也为参加实验室提供了一个评估和证明出具数据可靠性的客观手段,是参加实验室相应技术能力的有效证明。论文结合实例详细介绍能力验... 能力验证活动旨在了解参加检验实验室的整体水平和技术能力,提高该领域检测数据的有效性,能力验证活动也为参加实验室提供了一个评估和证明出具数据可靠性的客观手段,是参加实验室相应技术能力的有效证明。论文结合实例详细介绍能力验证活动的全过程。 展开更多
关键词 车用柴油 能力验证 Z比分数 结果分析
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Design and Experimental Research on Seedling Pick-Up Mechanism of Planetary Gear Train with Combined Non-circular Gear Transmission
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作者 Yaxin Yu Jikun Liu +4 位作者 Bingliang Ye Gaohong Yu Xuejun Jin Liang Sun Junhua Tong 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2019年第3期42-54,共13页
Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent ... Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent transmission, and a concave and convex locking arc device, has a large rigid impact. To solve these problems, according to the design requirements for a dryland plug seedling transplanting mechanism, a rotary seedling pick-up mechanism of a planetary gear train with combined non-circular gear transmission of incomplete eccentric circular and noncircular gears was proposed. This has the characteristics of two-times greater fluctuation of the transmission ratio in a cycle, and can achieve a non-uniform continuous drive. Through analysis of the working principle of the seedling pick-up mechanism, its kinematics model was established. The human–computer interaction optimization method and self-developed computer-aided analysis and optimization software were used to obtain a set of parameters that satisfy the operation requirements of the seedling pick-up mechanism. According to the optimized parameters, the structure of the seedling pick-up mechanism was designed, a virtual prototype of the mechanism was created, and a physical prototype was manufactured. A virtual motion simulation of the mechanism was performed, high-speed photographic kinematics tests were conducted, and the kinematic properties of the physical prototype were investigated, whereby the correctness of the theoretical model and the optimized design of the mechanism were verified. Further, laboratory seedling pick-up tests were conducted. The success ratio of seedling pick-up was 93.8% when the seedling pick-up efficiency of the mechanism was 60 plants per minute per row, indicating that the mechanism has a high efficiency and success ratio for seedling pick-up and can be applied to a dryland plug seedling transplanter. 展开更多
关键词 Dryland plug SEEDLING transplanter Rotary SEEDLING PICK-UP MECHANISM TRANSMISSION ratio Non-uniform continuous TRANSMISSION COMBINED NON-CIRCULAR gear TRANSMISSION Optimization design
Albumin-to-alkaline phosphatase ratio: A novel prognostic index of overall survival in cholangiocarcinoma patients after surgery 预览
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作者 Jian-Ping Xiong Jun-Yu Long +6 位作者 Wei-Yu Xu Jin Bian Han-Chun Huang Yi Bai Yi-Yao Xu Hai-Tao Zhao Xin Lu 《世界胃肠肿瘤学杂志:英文版(电子版)》 CAS 2019年第1期39-47,共9页
AIM To clarify the prognostic significance of preoperative albumin-to-alkaline phosphatase ratio (AAPR) in cholangiocarcinoma (CCA) subjects receiving surgery. METHODS In this retrospective study, we included 303 CCA ... AIM To clarify the prognostic significance of preoperative albumin-to-alkaline phosphatase ratio (AAPR) in cholangiocarcinoma (CCA) subjects receiving surgery. METHODS In this retrospective study, we included 303 CCA patients receiving surgery without preoperative therapy between 2002 and 2014. Clinicopathological characteristics (including AAPR) were analyzed to determine predictors of postoperative overall survival and recurrence-free survival (RFS). In addition, univariate and multivariate Cox proportional hazards models were conducted, followed by application of time-dependent receiver operating curves to identify the optimal cut-off. RESULTS Univariate and multivariate analyses revealed both decreased overall survival [hazard ratio (HR): 2.88, 95%CI: 1.19-5.78] and recurrence-free survival (HR: 2.31, 95%CI: 1.40–3.29) in patients with AAPR < 0.41 compared to those with AAPR ≥ 0.41. The optimal cut-off of AAPR was 0.41. Of the 303 subjects, 253 (83.5%) had an AAPR over 0.41. The overall 1-, 3- and 5-year survival rates were 70.2%, 38.0% and 16.5%, respectively in the low (< 0.41) AAPR group, which were significantly lower than those in the high (≥ 0.41) AAPR group (81.7%, 53.9%, and 33.4%, respectively)(P < 0.0001). Large tumor size, multiple tumors, and advanced clinical stage were also identified as significant predictors of poor prognosis. CONCLUSION Our outcomes showed that AAPR was a potential valuable prognostic indicator in CCA patients undergoing surgery, which should be further confirmed by prospective studies. Moreover, it is necessary to investigate the mechanisms concerning the correlation of low AAPR with poor post-operative survival in CCA patients. 展开更多
关键词 Albumin-to-alkaline PHOSPHATASE RATIO CHOLANGIOCARCINOMA Prognosis SURGERY Survival
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Sperm limitation affects sex allocation in a parasitoid wasp Nasonia vitripennis
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作者 Marlene Chirault Christophe Bressac +1 位作者 Marlene Goubault Charlotte Lecureuil 《昆虫科学:英文版》 SCIE CAS CSCD 2019年第5期853-862,共10页
Insect reproduction is influenced by various external factors including temperature, a well-studied constraint. We investigated to what extent different levels of sperm limitation of males exposed to different heat st... Insect reproduction is influenced by various external factors including temperature, a well-studied constraint. We investigated to what extent different levels of sperm limitation of males exposed to different heat stresses (34 and 36℃) afFect fem ales' offspring production and sex allocation in Nasonia vitripennis. In this haplodiploid parasitoid wasp attacking different species of pest flies, we investigated the effect of the quantity of sperm females received and stored in their spermatheca on their sperm use decisions, hence sex allocation, over successive ovipositions. In particular, we compared the sex allocation of females presenting three levels of sperm limitation (i.e.,mated with control, 34 ℃ heat-stressed or 36℃heat-stressed males) on each host they parasitized. To disentangle the potential reduction of sperm quality after a heat stress exposure from that of sperm quantity, we also explored the clutch size and sex ratio produced by fem ales that were partially sperm limited after copulating with multiply mated males. Independently of their sperm numbers, all types of fem ales produced a similar total number of offspring, but the more limited ones had fewer daughters. Sperm limitation further affected the distribution of daughters' production across time.In addition to constraints acting on female physiology, male fertility should therefore be considered in studies measuring reproductive outputs of insects submitted to heat stresses. 展开更多
关键词 heat stress multiple MATING OFFSPRING production dynamic SEX ratio SPERM STOCK SPERM use
超声造影技术对不同回声颈动脉斑块的应用研究 预览
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作者 高瑞奇 姚俊东 +1 位作者 王绍欣 张周龙 《医学研究杂志》 2019年第1期114-117,共4页
目的分析超声造影技术(contrast-enhanced ultrasound,CEUS)对不同回声的颈动脉粥样斑块(carotid plaque,CP)的易损性的应用价值。方法将纳入研究的119例患者依次进行常规颈动脉超声及超声造影检查,测量并比较分析不同回声组以及有症状... 目的分析超声造影技术(contrast-enhanced ultrasound,CEUS)对不同回声的颈动脉粥样斑块(carotid plaque,CP)的易损性的应用价值。方法将纳入研究的119例患者依次进行常规颈动脉超声及超声造影检查,测量并比较分析不同回声组以及有症状、无症状组CP的大小、增强强度(EI)及增强比率(Ratio)。结果不同回声斑块组间的增强强度比较差异有统计学意义(H=64.671,P<0.001);不同回声斑块组间的增强比率比较差异有统计学意义(H=61.754,P<0.001);有症状组的EI高于无症状组,差异有统计学意义(t=4.114,P<0.001);有症状组的Ratio高于无症状组,差异有统计学意义(t=4.275,P<0.001);有症状组与无症状组之间斑块直径的比较差异无统计学意义(P>0.05)。结论超声造影技术可以对CP的易损性进行量化分析,CP的增强强度、增强比率越高其稳定性越低。 展开更多
关键词 超声造影 颈动脉斑块 增强强度 增强比率
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Using of an Auxetic Structure as Reinforcement of a Bending Reinforced Concrete Beam 预览
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作者 Tarik Baran 《机械工程与自动化:英文版》 2019年第1期1-16,共16页
Materials which have negative Poisson’s ratio are entitled as auxetics.Auxetics can be designed as micro-to macro-sized structures.The use of auxetics in civil engineering structures has been studied only to a limite... Materials which have negative Poisson’s ratio are entitled as auxetics.Auxetics can be designed as micro-to macro-sized structures.The use of auxetics in civil engineering structures has been studied only to a limited extent.In this study,a re-entrant medium-size auxetic structure is employed as reinforcement of a reinforced concrete beam.The beam is subjected to static and dynamic loading conditions and then investigated by means of maximum vertical displacements of the beam.Besides,normal stresses and shear stresses of the concrete are also assessed.To interpret the performance of the auxetic reinforcement,obtained results are compared with the results of another beam which has non-auxetic reinforcement.The results show that these structures behave with bending compatibility as expected and due to the negative Poisson’s ratio,they led to shear strength increase.Auxetic structures can be employed as reinforcement in a beam.Besides,they can be employed without concrete to increase the shear strength in the case of high shear and impact strength if it is needed. 展开更多
关键词 AUXETIC RE-ENTRANT cell STRUCTURE NEGATIVE Poisson’s ratio AUXETIC REINFORCEMENT INDENTATION resistance
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Outcomes of adult patients adopting small-for-size grafts in living donor liver transplantation: A systematic review and meta-analysis 预览
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作者 Yue Yan Dao-Feng Zheng +1 位作者 Jun-Liang Pu Zhong-Jun Wu 《国际肝胆胰疾病杂志:英文版》 SCIE CAS CSCD 2019年第3期206-213,共8页
Background: Small-for-size graft(SFSG) has emerged as one of the very contentions in adult-to-adult living donor liver transplantation(LDLT) as a certain graft size is related to recipients’ prognosis. Graftto-recipi... Background: Small-for-size graft(SFSG) has emerged as one of the very contentions in adult-to-adult living donor liver transplantation(LDLT) as a certain graft size is related to recipients’ prognosis. Graftto-recipient weight ratio(GRWR)≥0.8% was considered as a threshold to conduct LDLT. However, this also has been challenged over decades as a result of technique refinements. For a better understanding of SFSG in practice, we conducted this meta-analysis to compare the perioperative outcomes and long-term outcomes between patients adopting the grafts with a lower volume(GRWR < 0.8%, SFSG group) and sufficient volume(GRWR ≥ 0.8%, non-SFSG group) in adult-to-adult LDLT. Data sources: The studies comparing recipients adopting graft with a GRWR < 0.8% and ≥ 0.8% were searched by three authors independently in Pub Med, Web of Science, Embase, the Cochrane Library, MEDLINE and Google Scholar databases until September 2018 and data were analyzed by RevMan 5.3.5. Results: Sixteen studies with a total of 3272 subjects were included in this meta-analysis. In terms of small-for-size syndrome(SFSS), no significant difference was found in subjects enrolled after year 2010(before 2010, OR = 3.00, 95% CI: 1.69–5.35, P = 0.0002;after 2010, OR = 1.23, 95% CI: 0.79–1.90, P = 0.36;P for interaction: 0.02). There was no significant difference in operative duration, blood loss, cold ischemia time, biliary complications, acute rejection, postoperative bleeding, hospitalization time, perioperative mortality, and 1-, 3-and 5-year overall survival rates between two groups. Conclusions: This meta-analysis suggested that adopting SFSG in adult LDLT has comparable outcomes to those with non-SFSG counterparts since 2010. 展开更多
关键词 LIVING DONOR liver transplantation Graft-to-recipient WEIGHT ratio Small-for-size GRAFT
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不同配比补肾活血方HPLC-UV-ELSD指纹图谱研究
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作者 刘思妍 王芯 +4 位作者 李艳玲 潘奕璇 李杨 谢学军 张梅 《辽宁中医杂志》 CAS 2019年第2期362-365,447共5页
目的:建立不同配比补肾活血方HPLC-UV-ELSD指纹图谱,并对各峰来源进行归属。方法:采用HPLC法,色谱柱为Inertsil OSD-SP C18(250 mm×4.6 mm,5μm);流动相为乙腈-0.05%甲酸水溶液(梯度洗脱),紫外检测器:检测波长为250 nm,蒸发光散射... 目的:建立不同配比补肾活血方HPLC-UV-ELSD指纹图谱,并对各峰来源进行归属。方法:采用HPLC法,色谱柱为Inertsil OSD-SP C18(250 mm×4.6 mm,5μm);流动相为乙腈-0.05%甲酸水溶液(梯度洗脱),紫外检测器:检测波长为250 nm,蒸发光散射检测器:漂移管温度为105℃,空气体积流量为3.2 L/min;进样量20μL;流速为1 mL/min。运用《中药色谱指纹图谱相似度评价系统(2008版)》对12批不同配比补肾活血方指纹图谱进行相似度计算,并对各共有峰进行药材来源归属及成分指认。结果:建立了不同配比补肾活血方指纹图谱;在其HPLC-UV指纹图谱中标定了23个共有峰,其中1~15、17、21号峰来源于葛根,18~20、22、23号峰来源于丹参,16号峰为丹参和葛根共有。在其HPLC-ELSD指纹图谱中标定了7个共有峰,其中1’~4’号峰来源于葛根,5’号峰来源于丹参,6’、7’号峰来源于人参。通过与对照品对照指认出复方中4个成分,分别是6/3’号峰为葛根素,22/5’号峰为丹酚酸B,10号峰为大豆苷,6’号峰为人参皂苷Rb1。结论:建立了不同配比补肾活血方HPLC-UV-ELSD指纹图谱,为筛选补肾活血方最佳配比、确定其防治DR药效物质奠定基础。 展开更多
关键词 补肾活血方 配比 HPLC-UV-ELSD 指纹图谱 均匀设计法
Effect of high Na2O addition on distribution of phosphorus in lowbasicity converter slag
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作者 Chang Su Ning-ning Lv +3 位作者 Jin-xing Yang Liu-shun Wu Hai-chuan Wang Yuan-chi Dong 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第1期42-51,共10页
In order to improve the dephosphorization efficiency of low-basicity converter slag and decrease the consumption of solid CaO,the effect of high Na2O addition(0-15 mass%)on the distribution of P2O5 between solid solut... In order to improve the dephosphorization efficiency of low-basicity converter slag and decrease the consumption of solid CaO,the effect of high Na2O addition(0-15 mass%)on the distribution of P2O5 between solid solution and matrix phase was investigated.The thermodynamic properties of slag samples were calculated by FactSage 7.0 software.Then,the dissolution behavior of phosphorus element from slag was studied.The results show that the mass fraction of 2CaO*SiO2-2CaO*Na2O*P2O5 solid solution increases when the Na2O content is increased in slag.However,the amount of formed solid solution changes little when the Na2O addition is more than 10 mass%.Moreover,the content of Na2O in solid solution would reach saturation when adding 15 mass%Na2O into the slag.With the increase in Na2O content in slag,the distribution ratio of P2O5 between solid solution and matrix phase increases.The values are evidently higher than the results reported in the literature.Meanwhile,the activity of P2O5 in matrix phase and the activity coefficient of P2O5 in solid solution are decreased with increasing the Na2O content in slag.Furthermore,the dissolution ratio of phosphorus in citric acid solution could be improved by adding Na2O into slag,but the increment of dissolution ratio would decrease when the Na2O content exceeds 10 mass%in slag. 展开更多
关键词 NA2O addition-Low-basicity converter slag PHOSPHORUS DISTRIBUTION ratio Thermodynamic property PHOSPHORUS DISSOLUTION behavior
Optimizing the Aspect Ratio of Cephalexin in Reactive Crystallization by Controlling Supersaturation and Seeding Policy 预览
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作者 Mingchen Li Zeren Shang Baohong Hou 《天津大学学报:英文版》 EI CAS 2019年第4期348-356,共9页
Batch crystallization in acidic aqueous solution of cephalexin was conducted by reactive crystallization with or without seeding. Supersaturation was generated by mixing ammonia and acidic aqueous solution of cephalex... Batch crystallization in acidic aqueous solution of cephalexin was conducted by reactive crystallization with or without seeding. Supersaturation was generated by mixing ammonia and acidic aqueous solution of cephalexin and controlled by solution feeding rate and seeding conditions. UV and Morphologi G3 were used to measure supersaturation and aspect ratio. Experimental results demonstrated that burst nucleation occurred and the products were needle-like at high supersaturation;meanwhile, the products were plate-like and had high aspect ratio at low supersaturation. Analysis of the measured supersaturation profi les and corresponding aspect ratio explained the mechanisms governing the aspect ratio. The optimized operating parameters were also proposed (seeding supersaturation is equal to 1.3, seed mass ratio 8% and feeding rate 368 μL/min). 展开更多
关键词 REACTIVE crystallization SUPERSATURATION control ASPECT ratio Crystal HABIT
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Spherical cavity-expansion model for penetration of reinforced-concrete targets 预览
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作者 Y.J.Deng W.J.Song X.W.Chen 《力学学报:英文版》 SCIE EI CAS CSCD 2019年第3期535-551,共17页
The feature of reinforcing bars is introduced into dynamic cavity-expansion theory. Based on the elastic-plastic response penetration model of plain (i.e., unreinforced) concrete (Forrestal and Tzou, 1997), a dynamic ... The feature of reinforcing bars is introduced into dynamic cavity-expansion theory. Based on the elastic-plastic response penetration model of plain (i.e., unreinforced) concrete (Forrestal and Tzou, 1997), a dynamic spherical cavity-expansion penetration model for reinforced-concrete targets is developed with consideration of the circumferential restriction effect derived from reinforcing bars in the crushed region. The theoretical solution and simplified calculation formula for the cavity radial stress in incompressible and compressible reinforced concrete are obtained by introducing a reinforcement ratio as the volume fraction of rebars in the concrete target. A damping function is presented to describe the restriction effect of a single layer of reinforcing bars on the surrounding concrete, thus establishing a model to calculate the penetration resistance of multilayer reinforced-concrete targets. Compared with test data for the penetration depth, this model considering the circumferential restriction effect produces better results compared with the existing theory. 展开更多
关键词 Dynamic cavity-expansion theory REINFORCED concrete PENETRATION resistance REINFORCEMENT RATIO
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Mechanism of formed-reinforcement in last roadway for pillar in the fully-mechanized gob-side entry 预览
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作者 Zhang Hongwei Wan Zhijun Zhang Yuan 《探索-地质与矿业研究》 2019年第1期8-14,共7页
In order to study the mechanism of the stability control of pillar by growing in the lastRoadway, methods involved the in-situ test and numerical simulation are employed. the ease of growth and the impact of filling r... In order to study the mechanism of the stability control of pillar by growing in the lastRoadway, methods involved the in-situ test and numerical simulation are employed. the ease of growth and the impact of filling ratio to formation of pillar are analyzed. results show that the Ru-in roadway besides pillar is filled with crushed rocks, which is relaxing for growing. further, under varied fill rates, the pillar experiences three formation stages, namely, 0-10%(marked increase), 20%-20%(slightly increase) and 25%-10%(stable ). the reasonable filling ratio locator in 20%. 展开更多
关键词 UNSTABLE overselling STRATA Narrow Coal PILLAR Working Face ends CAVING characteristics Growing information INFILL Ratio
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Depressed female cynomolgus mon keys(Macaca fascicularis)display a higher second-to-fourth(2D:4D)digit ratio
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作者 Wei Li Ling-Yun Luo +6 位作者 Xun Yang Yong He Bin Lian Chao-Hua Qu Qing-Yuan Wu Jian-Guo Zhang Peng Xie 《动物学研究》 CAS CSCD 2019年第3期219-225,共7页
This research aimed to provide evidenee of a relationship between digit ratio and depression status in the cynomolgus monkey(Macaca fascicularis).In stable cyno molgus mon key social groups,we selected 15 depressed mo... This research aimed to provide evidenee of a relationship between digit ratio and depression status in the cynomolgus monkey(Macaca fascicularis).In stable cyno molgus mon key social groups,we selected 15 depressed monkeys based on depressive-like behavioral criteria and 16 normal control mon keys.All animals were video recorded for two weeks,with the duration and frequency of the core depressive behaviors and 58 other behaviors in 12 behavioral categories then evaluated via behavioral analysis.Fin ger len gths from the right and left forelimb hands of both groups were measured by X-ray imagi ng.Fin ger length and digit ratio comparisons between the two groups were con ducted using Stude nt's Mest.In terms of the durati on of each behavior,signifies nt differences emerged in“Huddling”and five other behavioral categories,including Ingestive,Amicable,Parental,Locomotive,and Resting.In addition to the above five behavioral categories,we found that depressed mon keys spent less time in parental and rubbing back and forth behaviors than the control group.Furthermore,the 4th fin gers were significantly Ion ger in the left and right hands in the control group relative to the depressed mon keys.The sec ond?to?fourth(2D:4D)digit ratio in the left and right forelimb hands was significantly lower in the control group tha n that in the depressed group.Our fin dings revealed significant differences in finger lengths and digit ratios between depressed mon keys and healthy controls,which concords with our view that relatively high fetal testosterone exposure may be a protective factor against developing depressive symptoms(or that low fetal testosterone exposure is a risk factor). 展开更多
关键词 Fin ger length DIGIT ratio Major DEPRESSIVE disorder CYNOMOLGUS MON key
Experimental Study on Conversion Efficiency of A Floating OWC Pentagonal Backward Bent Duct Buoy Wave Energy Converter 预览
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作者 LI Meng WU Ru-kang +1 位作者 WU Bi-jun ZHANG Yun-qiu 《中国海洋工程:英文版》 SCIE EI CSCD 2019年第3期297-308,共12页
Wave tank tests were carried out to evaluate the total efficiency of a floating OWC Pentagonal Backward Bent Duct Buoy (PBBDB). Two kinds of turbine generators were used in tests. The incident wave power, pneumatic po... Wave tank tests were carried out to evaluate the total efficiency of a floating OWC Pentagonal Backward Bent Duct Buoy (PBBDB). Two kinds of turbine generators were used in tests. The incident wave power, pneumatic power and electricity were measured. The test results show that the primary efficiency can reach up to 185.98% in regular waves and 85.86% in irregular waves. The total efficiency from wave to wire with Wells turbine-generator set is 33.43% in regular waves and 15.82% in irregular waves. The peak total efficiency of the PBBDB with check valves equipped with the impulse turbine-generator set is 41.68% in regular waves and 27.10% in irregular waves. The efficiency of the turbine-generator set is about 30% in the tests. Obviously, the total efficiency can be further improved with the increasing of turbine efficiency. 展开更多
关键词 wave energy OSCILLATING Water Column (OWC) PBBDB CAPTURE Width Ratio (CWR) total efficiency
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