影响中晚期肝细胞肝癌手术切除预后的多因素分析

探讨影响中晚期肝细胞肝癌手术切除预后的因素。方法对130例中晚期大肝癌随访1～7年,采用单因素、多因素分析统计不同预后因素对患者生存率的影响。结果手术后1,3 ,5年生存率分别81.7%,24.3%,18.4%。单因素分析提示影响预后的因素为肝癌大小、是否早期复发、肝硬化情况、输血量;多因素分析提示肝癌大小、肿瘤早期复发是影响肝癌术后的预后因素。结论：中晚期肝癌手术切除预后仍不理想,重视围手术期处理,预防术后早期复发有望提高手术疗效 [英文摘要]Objective To study the prognostic factors in patients who received hepatectomy for large hepatocellular carcinoma(HCC). Methods 130 patients operated for large HCC were followed up for 1～7 years. Twenty possible factors were analyzed by Kaplan-Meier Log rank estimate. A multivariative survival analysis of these individal variable was undertaken using the cumulative survival rate by the computers COX proportional hazard. Result The overall cumulative survival rate at 1,3,5 years was 81.7%,24.3%,18.4% re..

干旱区绿洲棉田土壤CO2/N2O排放特征及减排潜力研究

农田生态系统作为温室气体排放源之一在全球碳氮循环中起到了重要作用。新疆绿洲农田是干旱区典型的灌溉农田生态系统，受人类活动的强烈影响，农田土壤CO2/N2O排放强度远高于同区域的其他生态系统，研究绿洲农田土壤CO2/N2O排放特征及调控措施具有重要的理论及实践意义。论文以干旱区绿洲棉田为研究对象，采用静态箱-气相色谱法阐明了绿洲棉田土壤CO2/N2O排放特征及主要影响因素，假设覆膜增加了土壤CO2排放、减少了土壤N2O排放，施肥促进了土壤CO2/N2O排放；大田和培育试验相结合探明了不同管理方式下棉田土壤CO2/N2O减排潜力，假设分期施肥降低了土壤CO2/N2O排放；基于DNDC模型提出了实现绿洲棉田土壤CO2/N2O减排的优化管理模式，预测了未来气候变化对棉田土壤CO2/N2O排放的影响，为干旱区绿洲农业生产管理和温室气体减排提供科学依据。主要结论如下：（1）绿洲棉田土壤CO2排放高峰期发生在棉花生长的花铃期（7-8月）。土壤CO2排放速率随温度升高呈指数增加，过高或过低的土壤含水量下土壤CO2排放速率均较低。全生育期内，58-77%的土壤N2O排放发生在滴灌施肥期（7-8月），土壤温度、湿度和矿质氮含量增加均利于土壤N2O产出与排放。较高的土壤温度和滴灌施肥措施可增加土壤硝化和反硝化细菌活性，利于土壤硝化和反硝化过程产出和排放N2O。（2）覆膜对土壤CO2和N2O排放的影响机制不同。覆膜保温保湿促进棉花生长，利于自养呼吸产出的CO2通过膜间土壤排放到大气中，土壤CO2排放量可增加7-9%。覆膜既能提高植物氮素利用效率减少土壤N2O产出，也可抑制土壤N2O传输利于N2O还原，全生育期土壤N2O排放量可减少19-28%。（3）施肥显著促进土壤CO2/N2O排放。土壤CO2排放量随施氮量增加呈线性增加，可能是施肥促进了棉花生长，增强了土壤微生物活性，利于土壤自养呼吸和异养呼吸产出和排放CO2。施氮肥为土壤微生物的硝化和反硝化过程提供底物，土壤N2O排放量随施氮量增加呈线性增加。观测期内，土壤N2O排放系数范围为0.28-0.70%，表明采用IPCC推荐的N2O排放系数（1%）会高估新疆干旱区绿洲膜下滴灌棉田土壤N2O排放量约一倍左右。 （4）培育试验中，分期施肥和施用硝化抑制剂均有效减少了土壤CO2/N2O排放，但分期施肥方式降低了施用硝化抑制剂下土壤N2O减排效率。田间试验中，施用硝化抑制剂没有显著影响滴灌施肥棉田土壤CO2排放，但抑制土壤铵态氮转化为硝态氮的硝化过程，土壤N2O排放量可减少23-42%。施用硝化抑制剂对棉花产量没有显著影响，降低土壤N2O排放产生的碳交易收益（6-11 RMB ha-1）远低于硝化抑制剂的成本投入（150 RMB ha-1），该方法不适用于减少新疆绿洲棉田土壤CO2/N2O排放。（5）DNDC有效模拟了覆膜对棉花生长和土壤CO2/N2O排放的影响。优化管理模式下模型模拟的结果表明，覆膜使棉田灌溉量和施氮量分别减少120 mm和10 kg N ha-1，使棉花产量、土壤CO2排放量和土壤有机碳增量分别增加了9%、10%和4%，使土壤N2O排放量减少了4%。不同气候变化情景下的模拟结果表明，未来气候变化使膜下滴灌棉田的棉花产量、土壤CO2排放量和作物经济收益分别增加了5-6%、7-9%和9-10%，土壤N2O排放量和棉田土壤有机碳增量分别减少了9-15%和21-29%。总之，未来气候变化利于新疆绿洲棉花增产，对土壤CO2/N2O排放产生的增温效应影响不大

Design and Synthesis of Oleanolic Acid Rings A and C Lactone Derivatives

齐墩果酸是一个五环三萜类天然产物, 具有多种生物活性和药理活性. 以齐墩果酸为起始原料, 采用间氯过氧苯甲酸以及过氧化脲等试剂进行其A环和C环内酯化修饰, 以较高收率获得了系列齐墩果酸A/C环内酯化衍生物. 所有产物均经~1H NMR、~(13)C NMR和高分辨质谱数据分析进行了结构确定, 其中有12个化合物为新化合物.Oleanolic acid (OA), a naturally occurring triterpene, was found to have a variety of biological and pharmacological properties. To expand its structural diversity, a series of oleanolic acid derivatives, including ring A and/or ring C expansion, were performed via Baeyer-Villiger reaction using m-CPBA and urea-hydrogen peroxide. The structures of all products were characterized by H-1 NMR, C-13 NMR and HRMS.天然药物及仿生药物国家重点实验室开放基金,昆明理工大学人才引进SCI(E)中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)中国科学引文数据库(CSCD)[email protected]; [email protected]

覆膜对绿洲棉田土壤CO2通量和CO2浓度的影响/Effects of plastic film mulching on soil CO2 effiux and CO2 concentration in an oasis cotton field[J]

基于静态箱法和气井法分别测定新疆棉田覆膜位置的土壤CO2通量和CO2浓度.结果表明:土壤CO2通量和CO2浓度时间变化特征与土壤温度变化趋势一致,均表现为7月较高,10月最低.观测期内,棉田土壤CO2累积排放量非覆膜处理为2032.81 kg C·hm-2,覆膜处理为1871.95 kg C·hm-2;而1 m深度内土壤CO2浓度非覆膜处理为2165～23986 μL·L-1,覆膜处理为5137～25945 μL·L-1,即覆膜减少了棉田土壤排放CO2的同时增加了土壤CO2积累量.覆膜和非覆膜处理下不同深度土壤CO2浓度和CO2通量的相关系数分别为0.60～0.73和0.57～0.75,表明地表释放的CO2强烈依赖于土壤剖面储存的CO2.覆膜和非覆膜处理下Q10值分别为2.77和2.48,表明覆膜处理下的土壤CO2通量对土壤温度变化的响应更敏感

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies