放射性肠炎的诊疗进展

放射性肠炎(radiation enteritis,RE)是因腹部、盆腔恶性肿瘤放疗引起的肠道并发症。RE呈现长期、间歇性加重的便血、里急后重等症状,严重时可以出现肠道穿孔、梗阻,给患者身体、心理和经济带来巨大负担。随着恶性肿瘤发病率的升高,放射治疗应用越来越广泛,RE发病率也随之逐年升高。放射性肠炎的诊断主要依赖于病史、内镜检查、影像学检查及组织学检查。目前治疗方案包括内科治疗、内镜治疗、外科治疗,但尚无高级别证据支持的治疗方案。为提高对RE的认识,并探讨其诊断和治疗策略,本文对其危险因素、临床表现、诊断与治疗最新研究进展进行综述。

感染新型冠状病毒的2型糖尿病患者的临床特征和结果——一项回顾性研究

据报道,糖尿病及其相关的代谢性疾病是新型冠状病毒肺炎(coronavirus disease 2019,COVID-19)患者的主要合并症。这项临床研究旨在调查有或没有合并糖尿病的COVID-19患者的临床特征、影像学和实验室检查、并发症、治疗方法以及临床结局。这项回顾性研究纳入2020年1月12日至3月25日208例经实验室确认的COVID-19的住院患者(≥45岁)。分析病历信息包括临床特征、影像学和实验室检查、并发症、治疗和临床结果。其中,96名(46.2%)患者患有2型糖尿病。在COVID-19合并2型糖尿病患者中,高血压(58.3%vs.31.2%)、冠心病(17.1%vs.8.0%)和慢性肾脏病(6.2%vs.0%)的共存率明显高于没有2型糖尿病的COVID-19患者。COVID-19合并2型糖尿病患者的CT胸部扫描异常频率和程度显著增加,包括毛玻璃样混浊(85.6%vs.64.9%,P<0.001)和双侧斑片状阴影(76.7%vs.37.8%,P<0.001)。此外,患有糖尿病的COVID-19患者的血糖水平[7.23 mmol·L^-1(IQR:5.80~9.29)vs.5.46 mmol·L^-1(IQR:5.00-6.46)]、血液中低密度脂蛋白胆固醇(low-density lipoprotein cholesterol,LDL-C)[2.21 mmol·L^-1(IQR:1.67~2.76)vs.1.75 mmol·L^-1(IQR:1.27~2.01)]和收缩压[130 mmHg(IQR:120~142)vs.122 mmHg(IQR:110~137),P<0.001]显著高于没有糖尿病的患者(P<0.001)。2型糖尿病和其他代谢性疾病共存于COVID-19患者中,这可能会增加发病率并加重COVID-19的病情。血糖和脂质代谢的最佳管理是确保更好的临床结果的关键。对于患有糖尿病及其他基础和慢性代谢性疾病的COVID-19患者,应提高临床警惕性。

Cytocompatibility of High Nitrogen Nickel-Free Stainless Steel for Orthopedic Implants

Cytocompatibility of high nitrogen nickel-free stainless steel （HNS） with different nitrogen content was evalu- ated and compared with a conventional austenitic stainless steel 317L. The MTT assay （3-（4,5-dimethylthiazol- 2-yl）-2,5-diphenyltetrazolium bromide） was performed on MG63 osteoblasts to assess the cytotoxicity. The expression of selected marker typical of differentiated osteoblasts, such as alkaline phosphatase activity （AKP）, was also monitored in MG63 cells cultured on the tested materials. As a result, HNS had higher cell growth than 317L; meanwhile the cytocompatibility was increased with increasing nitrogen content. Furthermore, HNS enhanced osteoblasts differentiation, as confirmed by AKP activity. Overall these facts indicated that HNS had higher cytocompatibility than 317L and the nitrogen content contributed to the higher cytocompatibility of HNS. The influence of nitrogen on surface energy further explained the cytocompatibility of HNS.

Mathematical model study on the damage of the liquid phase to productivity in the gas reservoir with a bottom water zone

The production process in the gas reservoir with an aquifer is complex.With gas production,aquifer water could possibly flow into the production well and accumulate within the well bore,which leads to a lower production rate and may even block the producer.However,few studies in the literature investigate the damage caused by the liquid phase in this kind of reservoir or predict gas productivity using the relationship between reservoir pressure and water gas ratio(WGR).For this reason,it is important to know the effects of the formation of liquid phase behavior on production when an aquifer is present under a gas reservoir.From the results of published literature reviews,we found that studies focused on the production of a gas reservoir with bottom water.Nevertheless,for gas well damage from the liquid phase behavior,we found that there was no statistical data or mathematical model of the relationship between reservoir pressure and the gas oil ratio(GOR),which affects production.In this research,based on the theory of fluid flow in porous media,a new mathematical model of water and gas production and a new equation on gas well productivity is developed.To verify the model and equation,gas production data collected from the field are applied.By analyzing the typical gas reservoir with bottom water and the collected data,influences from the liquid phase behavior are shown.In this way,mathematical relationships between reservoir pressure and the WGR and between the GOR and production decline were obtained.The new gas productivity model is derived from the gas and water pseudo pressure functions,which can be applied to analyze well damage caused by the liquid phase.In order to verify the mathematical model,production data were collected from a typical gas reservoir with an aquifer located in the Changxing gas reservoir.The results indicate that a semi-logarithmic linear relationship is obtained between the WGR and productivity decrease.When the WGR increases from 0.5 to 15m3/104m3,damage caused by liquid phase decreases to 59%.The tendency of gas productivity in the Changxing gas reservoir was obtained so that it decreases as reservoir pressure decreases and increases as the WGR decreases.The gradient of the gas productivity deduction increases as the WGR increases.By the end of the data analysis,two linear equations indicating the relationship between gas productivity and reservoir pressure and the relationship between gas productivity and the water gas ratio are obtained:QAOF?A1lnWGRB1 and QAOF?A2lnPB2,respectively.

怀山药类原球茎的诱导形成与植株再生

为提高山药离体繁殖的速度,缩短繁殖周期,以铁棍山药(Dioscorea opposita cv.‘Tiegun’)带腋芽茎段为材料,对类原球茎的诱导、增殖、分化与植株再生进行了研究。结果表明,铁棍山药类原球茎诱导的最适培养基为MS+1.0 mg·L^(–1)TDZ+30 g·L^(–1)蔗糖,增殖的最适培养基为MS+9 mg·L^(–1) 6-BA+30 g·L^(–1)蔗糖,分化的最适培养基为MS+2 mg·L^(–1) KT+0.02mg·L^(–1) NAA+30 g·L^(–1)蔗糖,最适生根培养基为1/4MS+0.05 mg·L^(–1) NAA+1.0 mg·L^(–1) PP333+15 g·L^(–1)蔗糖,生根率达80%,移栽成活率可达85%。类原球茎的诱导形成及植株再生体系的建立为怀山药种苗的快速繁殖提供了一条新途径。