人牙龈成纤维细胞原代培养方法的比较研究

目的：建立和评价人牙龈成纤维细胞原代培养方法,并观察其生物学特性。方法：分别用组织块法、2种改良酶消组织块法培养人牙龈成纤维细胞（HGF）,用形态学、免疫荧光鉴定细胞来源。通过活细胞观察,MTT比色实验研究细胞体外生物特性。比较3种培养方法培养HGF的效果。结果：细胞抗波形丝蛋白染色阳性,抗角蛋白染色阴性,符合人牙龈成纤维细胞的形态学特征和生物学特性。组织块法、改良酶消组织块法（翻瓶法）、改良酶消组织块法（盖玻片法）的细胞培养成功率分别为26.7%、54%、60%。组织块法和2种改良酶消组织块法间的成功率差异有显著性（P〈0.01）,2种改良酶消组织块法间的成功率差异无显著性（P〉0.05）。结论：本实验建立的细胞系为人牙龈成纤维细胞。2种改良酶消化组织块法可显著提高人牙龈成纤维细胞原代培养成功率。     

Advances in Bovine Coronavirus Epidemiology

Bovine coronavirus (BCoV) is a causative agent of enteric and respiratory disease in cattle. BCoV has also been reported to cause a variety of animal diseases and is closely related to human coronaviruses, which has attracted extensive attention from both cattle farmers and researchers. However, there are few comprehensive epidemiological reviews, and key information regarding the effect of S-gene differences on tissue tendency and potential cross-species transmission remain unclear. In this review, we summarize BCoV epidemiology, including the transmission, infection-associated factors, co-infection, pathogenicity, genetic evolution, and potential cross-species transmission. Furthermore, the potential two-receptor binding motif system for BCoV entry and the association between BCoV and SARS-CoV-2 are also discussed in this review. Our aim is to provide valuable information for the prevention and treatment of BCoV infection throughout the world.     

前交叉韧带重建术后短期内移植体黏性变化

目的 研究前交叉韧带重建(anterior cruciate ligament reconstruction, ACLR)术后短时间内移植体黏性的变化规律。方法 选择6只雄性新西兰兔,以跟腱为移植体制作单侧膝关节ACLR动物模型。ACLR术后15 d将实验兔安乐死,取出移植体、健康的前交叉韧带(anterior cruciate ligament, ACL)和跟腱。测量移植体的截面积,分别进行0.1、1 MPa平衡条件的蠕变实验,并计算黏性系数,总结移植体的黏性变化规律,与健康ACL进行对比。结果 移植体的截面积在手术后15 d内缓慢上升。ACL与移植体的黏性呈非线性变化。在不同应力下,黏性系数有较大差异。移植体黏性系数随ACLR术后时间呈下降趋势,但在低应力下更明显。结论 本文建议,ACLR术后早期康复过程中,应使用助行器,降低步频,并避免踢、踹等对关节冲击的运动。     

Electrochemical Corrosion Behaviour of X70 Steel under the Action of Capillary Water in Saline Soils

In this paper, the electrochemical corrosion behavior of X70 steel in saline soil under capillary water was simulated by a Geo-experts one-dimensional soil column instrument. A volumetric water content sensor and conductivity test were used to study the migration mechanism of water and salt (sodium chloride) under the capillary water. The electrochemical corrosion behavior of the X70 steel in the corrosion system was analyzed by electrochemical testing as well as the macroscopic and microscopic corrosion morphology of the steel. The test results showed that the corrosion behavior of X70 steel was significantly influenced by the rise of capillary water. In particular, the wetting front during the capillary water rise meant that the X70 steel was located at the three-phase solid/liquid/gas interface at a certain location, which worsened its corrosion behavior. In addition, after the capillary water was stabilized, the salts were transported with the capillary water to the top of the soil column. This resulted in the highest salt content in the soil environment and the most severe corrosion of the X70 steel at this location.     

中美婴儿运动表现测试常模差异分析

目的比较中美婴儿运动表现测试(TIMP)常模,明确本地化研究和修正的重要性,为指导TIMP在国内的推广提供依据。方法经TIMP手册正反译,评估人员培训、信度考核后,分别在华东、华北、华南、华中、西南、西北、东北区域11家医疗机构采样,建立中国TIMP常模,并就样本情况、得分情况及亚组分类与美国常模进行对比。结果中国TIMP常模共13个周龄组,样本总数为1 035例,其中男性占56%,女性占44%,汉族占比95%,少数民族5%,早产儿和足月儿分别占比31%、69%;美国常模共12个周龄组,样本总数为990例,其中男性占52%,女性48%,白种人占58%,黑种人25%,高危、中危、低危婴儿分别占比35%、30%、35%。中国TIMP常模各周龄组得分均值低于同周龄组的美国常模(P<0.01);中国常模第10、50、90百分位数曲线低于美国常模。中国常模足月儿与早产儿亚组对比,大多数周龄组得分无显著差异;美国常模中高危儿亚组得分显著低于低危组(P<0.001)。结论基于两国人口特征和儿童保健发展现状的不同,中美TIMP常模取样人群存在差异。中国常模各周龄组的得分均值低于美国常模同周...     

Resistance of Xanthomonas oryzae pv. oryzae to Lytic Phage X2 by Spontaneous Mutation of Lipopolysaccharide Synthesis-Related Glycosyltransferase

Phage therapy is a promising biocontrol management on plant diseases caused by bacterial pathogens due to its specificity, efficiency and environmental friendliness. The emergence of natural phage-resistant bacteria hinders the application of phage therapy. Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of the devastating bacterial leaf blight disease of rice. Here, we obtained a spontaneous mutant C2R of an Xoo strain C2 showing strong resistance to the lytic phage X2. Analysis of the C2R genome found that the CDS2289 gene encoding glycosyltransferase acquired a frameshift mutation at the 180th nucleotide site, which also leads to a premature stop mutation at the 142nd amino acid. This mutation confers the inhibition of phage adsorption through the changes in lipopolysaccharide production and structure and bacterial surface morphology. Interestingly, glycosyltransferase-deficient C2R and an insertional mutant k2289 also showed reduced virulence, suggesting the trade-off costs of phage resistance. In summary, this study highlights the role of glycosyltransferase in interactions among pathogenic bacteria, phages and plant hosts, which provide insights into balanced coevolution from environmental perspectives.     

水凝胶的生物力学研究进展

水凝胶是生物医用领域的重要生物材料,也是近年来的研究热点。但人体内的细胞与组织的微环境和调控机制非常复杂,水凝胶应用于再生修复领域仍存在一些待解决的科学问题。随着生物力学的发展,越来越多的研究者发现除了关注水凝胶的材料学及生物学特性以外,其生物力学特性也是调控细胞功能、影响组织再生修复的关键因素之一。因此,本文总结了水凝胶材料的生物力学研究进展,并对未来的研究工作进行了展望。     

降纤酶联合抗凝药预防老年肺癌术后深静脉血栓形成

目的 探讨降纤酶联合抗凝药预防老年肺癌术后深静脉血栓形成.方法 选取2019年4月～2020年4月我院收治的72例老年肺癌术后患者为研究对象,应用随机数字法分为两组,对照组单独进行抗凝药的药物治疗,研究组则进行降纤酶联合抗凝药的药物治疗.观察分析两组患者的深静脉血栓、下肢肿胀、各项指标及股静脉血流峰值和平均流速情况.结...     

HBx通过Notch信号通路在正常免疫小鼠体内导致肝癌的作用机制

目的 构建长期携带乙型肝炎病毒X(hepatitis B virus X,HBx)的正常免疫小鼠模型,以探讨HBx在体内导致肝癌发生的机制.方法 将转染HBx的肝前体细胞经肝门静脉注射入昆明小鼠体内构建动物模型,分别于术后30、90、180、360 d收取肝脏组织,Western blot和RT-qPCR检测HBx的表...     

钬激光对复杂输尿管结石的诊疗价值 (附56例报告)

目的:探讨钬激光治疗复杂性输尿管结石有效性及安全性。方法:回顾性分析2003年12月～2005年12月收治的经输尿管镜钬激光治疗复杂性输尿管结石56例患者的临床资料。56例患者均有不同程度肾积水。12例并发结石远端输尿管狭窄,27例并发单纯息肉,9例并发息肉形成并包裹结石,8例并发结石嵌顿、与输尿管壁紧密粘连,24例有接受ESWL治疗史,5例曾行输尿管切开取石术。双侧输尿管结石伴肾功能减退6例。结果:56例中,53例单次手术碎石成功,单次手术结石粉碎率达94.6%(53/56),1例在钬激光碎石过程中结石移位于肾盏,术后再行ESWL治疗,1例进镜时输尿管穿孔,1例巨大结石行钬激光碎石失败改为开放手术。结论:输尿管镜钬激光碎石术治疗复杂性输尿管结石安全、有效、微创,可作为治疗复杂性输尿管的首选方法。