不同氮效率水稻品种根系生理生态指标的差异

以氮素利用效率差异大的两个水稻品种(氮高效品种南光和氮低效品种Elio)作为试验材料,设计高低两个供氮水平,在温室砂培条件下研究了不同氮效率水稻高效吸收利用氮素的根系生物学特性及生理机制.结果表明,在两个供氮水平下,氮高效水稻南光的产量均显著大于氮低效水稻,增幅在50%以上.随着供氮水平的提高,两个水稻品种植株的总吸氮量和干物质量随之增加,氮高效水稻南光的生育后期吸氮量和地上部及根系的生物量显著高于氮低效水稻Elio;氮高效水稻品种南光根系形态参数对氮素营养的响应度高于氮低效品种Elio,高氮处理下,南光较低氮处理分别增加127%(总根长)和114%(根系表面积),而Elio仅增加92%(总根长)和82%(根系表面积),而且Elio在齐穗期后根系形态参数水平下降显著;南光的根系伤流强度在拔节期较氮低效水稻Elio高出11%(1mmol L-1)和32%(5mmol L-1),灌浆期南光较Elio高出12%(1mmol L-1)和12%(5mmol L-1),差异均显著.由本试验结果可推断根系形态及根系活力的差异是造成水稻氮效率差异的重要原因之一.     

Interactions between glucosinolate- and myrosinase-containing plants and the sawfly Athalia rosae

Several insects have specialised on using Brassicaceae as host plants. Therefore, they evolved metabolic pathways to cope with the defensive glucosinolate–myrosinase system of their diet. Larvae of the turnip sawfly, Athalia rosae L. (Hymenoptera: Tenthredinidae), incorporate various glucosinolates from their hosts into their haemolymph. The ability to sequester these metabolites makes A. rosae a useful model system to study mechanisms of glucosinolate metabolism in this species compared to other specialists, and to study effects of sawfly feeding on levels of glucosinolates and their hydrolysing enzymes in plants. The levels of plant metabolites might in turn directly affect the performance of the insect. On the one hand, costs for glucosinolate uptake and avoidance of myrosinase activity were postulated. On the other hand, sequestration of glucosinolates can be part of the insect’s defence against several predators. Here, the findings on glucosinolate metabolic pathways are compared between different herbivores and the sawfly. The impact of different glucosinolate levels and myrosinase activities on the performance of A. rosae is discussed. Furthermore, effects of feeding by A. rosae larvae on the chemical composition and enzyme activities of various Brassicaceae species are summarised. Induction patterns vary not only between different plant species and cultivars but also due to the inducing agent. Finally, the plant–herbivore interactions are discussed with regard to the sawflies’ defence abilities against different carnivore guilds.     

T cell activation in abnormal perinatal events

The aim of this study was to determine the percentage of CD45RO⁺ T cells in umbilical cord blood from neonates born at less than 37 weeks of gestation. Fifty-nine patients were enrolled in this study, including 49 with preterm and 10 with term deliveries. Preterm deliveries were divided into two categories; spontaneous (Group A, n = 31) and indicated (Group B, n = 18). Perinatal infection was categorized as C-CAM, H-CAM and neonatal infection. The percentage of CD45RO⁺ T cells in the umbilical cord was assessed using flow cytometry. IL-6 was measured using ELISA. In Group A, the percentage of CD45RO⁺ T cells and concentrations of IL-6 in patients with perinatal infection ( n = 18) were significantly higher than in those without perinatal infection ( n = 13). A significant correlation between percentage of CD45RO⁺ T cells and IL-6 concentrations was observed in the cord blood ( r = 0.62, P = 0.001). In Group B, pink–tinged amniotic fluid was observed in seven cases. In these cases, an increase in the percentage of CD45RO⁺ T cells (>10%) was noted. In the cases without perinatal infection, which included all those delivered at term ( n = 32), no correlation was observed between the percentage of CD45RO⁺ T cells and gestational age at delivery ( r =−0.139, P = 0.448). We concluded that a high percentage of CD45RO⁺ cord blood T cells is observed not only in perinatal infection, but also in the presence of abnormal perinatal events such as maternal bleeding in preterm gestation.     

经股动脉导管介入支气管动脉栓塞救治难治性大咯血

目的：1996—3至2005—12期间我科与介入放射科合作,对66例内科方法未能止血的大咯血患者行支气管动脉介入栓塞术止血。观察分析止血效果及并发症。方法：患者在1250数字减影机下,经股动脉插入美国COOK公司生产的3—5FCobra导管。找到支气管动脉,造影后确定出血部位,在明确无栓塞禁忌症后,以明胶海绵粉末或PVA颗粒栓塞支气管动脉,观察止血状况及并发症。结果：总体止血率95．3％（61／64）,半年内9例复发咯血,但咯血量明显减小,复发率14．1％（9／64）。仅1例栓塞后未止血。2例动静脉瘘患者不能实行栓塞。15例出现发热,占23．4％（15／64）,所有患者均不同程度出现气短,吸氧后缓解。结论：支气管动脉栓塞救治难治性大咯血十分有效、可靠且较为安全。     

血清APOC1、LDH及炎性感染指标在难治性支原体肺炎患儿中的表达水平及其与肺通气功能、预后效果的相关性分析

摘要 目的：分析血清载脂蛋白C1（APOC1）、乳酸脱氢酶（LDH）及炎性感染指标在难治性支原体肺炎患儿中的表达水平及其与肺通气功能、预后效果的相关性。方法：选择我院自2019年1月至2022年12月接诊的130例难治性支原体肺炎患儿作为观察组，另选同期在我院体检且结果正常的儿童作为对照组。检测两组入选者血清APOC1、LDH及炎性感染指标[C反应蛋白（CRP）、白细胞介素-6（IL-6）]表达水平、肺通气功能指标[用力肺活量（FVC）、第1秒用力呼气容积（FEV₁）、呼气峰流速（PEF）]；观察组患儿均严格按照《儿童社区获得性肺炎诊疗规范（2019年版）》接受治疗，通过ROC曲线下面积（AUC）评价血清APOC1、LDH及炎性感染指标对难治性支原体肺炎患儿预后不良的预测效能。结果：观察组血清APOC1、LDH、CRP、IL-6表达水平均高于对照组（P＜0.05）；在观察组患儿中，重症组血清APOC1、LDH、CRP、IL-6表达水平均高于轻症组（P＜0.05）；经Pearson相关性分析，难治性支原体肺炎患儿血清APOC1、LDH、CRP、IL-6表达水平均与FVC、FEV1、PEF呈负相关（P＜0.05）；经多因素Logistic回归分析，难治性支原体肺炎患儿血清APOC1、LDH、CRP、IL-6均是其预后不良的独立预测因素（P＜0.05）；经ROC曲线分析，难治性支原体肺炎患儿血清APOC1、LDH、CRP联合IL-6预测其预后不良的AUC为0.930。结论：血清APOC1、LDH及炎性感染指标在难治性支原体肺炎患儿中的表达水平明显升高，与其肺通气功能密切相关，其中APOC1、LDH、CRP联合IL-6预测预后不良的效能较好，值得进一步研究应用。     

Mechano-electric feedback and atrial fibrillation

Atrial fibrillation frequently occurs under conditions associated with atrial dilatation suggesting a role of mechano-electric feedback in atrial arrhythmogenesis. Although atrial arrhythmias may be due both to abnormal focal activity and reentrant mechanisms, the majority of sustained atrial arrhythmias have been ascribed to reentrant activity. Atrial stretch may contribute to focal arrhythmias by inducing afterdepolarizations and to reentrant arrhythmias by increasing the atrial surface, by shortening the refractory period and/or slowing the conduction velocity and by increasing their spatial dispersion. Experimental and clinical studies have demonstrated that changes in mechanical loading conditions may modulate the electrophysiological properties of the atria. These studies have, for the most part, involved the effects of acute stretch on atrial refractoriness. While studies in humans and intact animals yield divergent results due to the variety of loading conditions and neurohumoral influences, experimental studies in isolated preparations clearly show that atrial refractory period and action potential duration at early levels of repolarization shorten by acute atrial dilatation. Both experimental and human studies have shown that acute atrial stretch is arrhythmogenic and may induce triggered premature beats and atrial fibrillation.     

Evaluation of process variables in bench-scale bio-oxidation of the Olympias concentrate

Abstract: A statistically designed set of eight bio-oxidation tests on the Olympias concentrate was conducted in bench-scale equipment to evaluate the effects of important variables on pyrite/arsenopyrite oxidation and gold extraction. The variables studied were total retention time, feed solid concentration and particle size. High degrees of arsenopyrite oxidation were observed in all tests, as the arsenopyrite oxidation was very fast and therefore not dependent on the variables within the studied range. Statistical analysis of the experimental data reveals that the pyrite oxidation and gold extraction are dependent mainly on the retention time and to a lesser extent on the particle size. The feed solid concentration had a small influence only on the gold extraction. Regressed equations of the experimental data can be used to predict proper operating conditions.     

AIMS65评分联合血清GAS、PGE2、BAR对急性非静脉曲张性上消化道出血患者预后的评估价值

摘要 目的：探讨AIMS65评分联合血清胃泌素（GAS）、前列腺素E₂（PGE₂）、血尿素氮/白蛋白比值（BAR）对急性非静脉曲张性上消化道出血（ANVUGIB）患者内镜下止血治疗后预后的评估价值。方法：选取2020年5月～2022年5月北京市和平里医院消化内科收治的108例的ANVUGIB患者,根据患者住院28 d内的预后分为预后不良组和预后良好组。收集患者临床资料,检测血清GAS、PGE₂水平和计算AIMS65评分、BAR。采用单因素和多因素Logistic回归分析ANVUGIB患者内镜下止血治疗后预后不良的影响因素,受试者工作特征（ROC）曲线分析AIMS65评分、GAS、PGE₂和BAR对ANVUGIB患者内镜下止血治疗后预后不良的评估价值。结果：108例ANVUGIB患者预后不良发生率为37.96％（41/108）。单因素分析显示,预后不良组年龄大于预后良好组,心率、休克指数、AIMS65评分、GAS、BAR高于预后良好组,PGE₂水平低于预后良好组（P均＜0.05）。多因素Logistic回归分析显示,年龄增加和休克指数、AIMS65评分、GAS、BAR升高为ANVUGIB患者内镜下止血治疗后预后不良的独立危险因素,PGE₂升高为其独立保护因素（P均＜0.05）。ROC曲线分析显示,AIMS65评分联合GAS、PGE₂和BAR评估ANVUGIB患者内镜下止血治疗后预后不良的曲线下面积大于AIMS65评分、GAS、PGE₂和BAR单独评估。结论：预后不良的ANVUGIB患者AIMS65评分、GAS、BAR均高于预后良好的患者,AIMS65评分联合GAS、PGE₂和BAR评估ANVUGIB患者内镜下止血治疗后预后的价值较高。     

Refractory petrochemical wastewater treatment by K2S2O8 assisted photocatalysis

The K₂S₂O₈ assisted photocatalytic system was applied for treating refractory petrochemical wastewater. Co-TiO₂/zeolite catalyst synthesized by sol-gel method was demonstrated to possess a good activity towards mineralization of the refractory petrochemical wastewater in the K₂S₂O₈ assisted photocatalytic system. Orthogonal design was employed to optimize the reaction parameters, according to the results, K₂S₂O₈ dosage was the most prominent impact factor. More experiments were conducted to further enhance the COD removal efficiency. In consideration of both efficiency and costs, the petrochemical wastewater was treated in the K₂S₂O₈ assisted photocatalytic system at pH 4, K₂S₂O₈ dosage 2.03 g/L, catalyst amount 250 g/L with irradiation by 1 lamp and aeration. The COD removal efficiency reached up to 93.4% with a rate constant of 1.14 × 10⁻² per min, and Co-TiO₂/zeolite showed a good stability towards the K₂S₂O₈ assisted photocatalytic degradation of petrochemical wastewater.     

立止血对家兔止血效果的研究

目的 观察立止血对家兔的止血效果,为该药的临床应用及研究类似产品提供可借鉴的资料。方法 测定家兔静注立止血前、后的因时间和凝血时间值,经统计学分析。结果 静沪立止血后所测不同时估（测至２４ｈ）的出血时间、凝血时间均经注药前自身空白对照缩短,具阶段性。结论 初步证实立止血具有高效、速效、长效、安全的作用特性,同时揭示立止血的止血功能具阶段性的特点。