Liquid Guayule Natural Rubber,a Sustainable Processing Aid,Enhances the Processability,Durability and Dynamic Mechanical Properties of Rubber Composites

Petroleum-based oils are widely used as processing aids in rubber composites to improve processability but can adversely affect rubber composite performance and increase carbon footprint. In this research, liquid guayule natural rubber (LGNR), produced from guayule natural rubber, was used as a renewable processing aid to replace naphthenic oil (NO) in Hevea natural rubber, styrene-butadiene rubber (SBR) and guayule natural rubber (GNR) composites. The rheological properties, thermal stability, glass transition temperature, dynamic mechanical properties, aging, and ozone resistance of rubber composites with and without NO or LGNR were compared. Natural and synthetic rubber composites made with LGNR had similar processability to those made with NO, but had improved thermal stability, mechanical properties after aging, and ozone resistance. This was due to the strong LGNR–filler interaction and additional crosslinks formed between LGNR and the rubber matrices. The glass transition temperature of SBR composites was reduced by LGNR because of its increased molecular mobility. Thus, unlike NO, LGNR processing aid can simultaneously improve rubber composite durability, dynamic performance and renewability. The commercialization of LGNR has the potential to open a new sustainable processing-aid market.     

不同模式新辅助治疗食管癌的疗效分析

目的 探讨食管癌不同模式新辅助治疗的疗效分析。方法 回顾性分析2015年1月至2022年5月于安阳市肿瘤医院行新辅助治疗的食管鳞癌(ESCC)患者的资料,共纳入542例患者,其中放化疗(NCRT)组137例,化疗(NCT)组241例,免疫加化疗(NICT)组164例;女性198例,男性344例;≤65岁289例,＞65岁253例。首要研究终点包括主要病理缓解(MPR)率、病理完全缓解(pCR) 率,次要研究终点包括总生存(OS)、无进展生存(PFS)和安全性。生存分析采用Kaplan-Meier方法,并采用Log-rank检验进行组间比较。采用Cox比例风险回归模型进行预后因素分析。结果 NCRT组的MPR率和pCR率分别为66.4%(91/137)和35.8%(49/137),NCT组分别为35.3%(85/241)和6.6%(16/241),NICT组分别为63.4%(104/164)和31.1%(51/164)(χ²=1.67, P＜0.001)。NCRT组的1、2、3年的OS分别为89.8%、82.3%、72.3%,NCT组分别为85.9%、71.4%、61.4%,NICT组分别为91.9%、81.5%、77.8%,差异有统计学意义(χ²=9.20,P＜0.01);NCRT组的1、2、3年的PFS分别为81.5%、67.9%、66.6%,NCT组分别75.9%、61.0%、53.5%,NICT组分别为80.1%、65.5%、65.3%,差异有统计学意义(χ²=4.62,P＜0.05)。多因素分析显示,治疗方式、T分期、N分期是OS的独立影响因素(P＜0.05)。3组不良反应及术后并发症差异无统计学意义(P＞0.05)。结论 与NCT对比,NICT与NCRT有更高的pCR、MPR和生存获益,因此新辅助免疫可作为食管癌术前治疗手段之一,但仍需大型的随机对照研究进一步证实。     

超声诊断颌下腺炎的临床应用

目的探讨超声诊断颌下腺炎的临床应用价值。方法选取101例经手术证实的颌下腺炎的超声图像,分析颌下腺的大小、形态、内部回声及彩色血流情况。结果101例颌下腺炎中,急性炎症2例,慢性炎症99例,超声与手术病理结果符合率为98%。结论超声对颌下腺炎的诊断准确率较高,并能与颌下区占位性病变相鉴别。     

利妥昔单抗治疗难治性激素耐药型肾病综合征的疗效和安全性

目的:探讨利妥昔单抗(RTX)治疗儿童难治性激素耐药型肾病综合征(SRNS)的疗效和安全性。方法:回顾性分析2013年9月至2018年3月东部战区总医院儿科收治并接受RTX治疗的10例难治性SRNS患儿的临床资料。结果:10例患儿发病年龄(4.47±2.75)岁,男女各5例;5例(50%)肾活检为局灶节段性肾小球肾炎,...     

Study on the Material Properties of Microconcrete by Dynamic Model Test

As an important water conveying structure, the seismic safety of the hydraulic aqueduct has attracted considerable interest. Different from the general bridge structure, the seismic analysis of the aqueduct structure needs to consider its fluid–structure interaction. The existing numerical simulation methods cannot truly reflect the fluid–solid coupling mechanism. Therefore, scholars began to use shaking table tests to study the fluid–structure interaction mechanism. However, the research is immature, and it is mostly focused on the seismic response analysis, and there are few studies on the model test similarity ratio and model material properties. Based on this, in this paper, according to the requirements of the test similarity ratio, the orthogonal experiment was used to explore the influence of barite sand content, water–cement ratio, fine sand ratio, and lime ratio on the mechanical properties of microconcrete. The performance indicators of microconcrete under different mix ratios vary widely, with a minimum variation of 19% and a maximum of 102%. Barite sand has the most significant control effect on the density, and the water–cement ratio has the most significant control effect on the compressive strength and elastic modulus. The density variation range is 2.37–2.81 g/cm³, the cube compressive strength variation range is 18.37–36.94 MPa, and the elastic modulus variation range is 2.11 × 10⁴–3.28 × 10⁴ MPa. This study will provide certain evidence for the similarity ratio design and material selection of the scaled model test of the fluid–solid coupling structure.     

EXPERIMENTAL SPINAL CORD TRAUMATIC INJURY OF THE CAT TREATED WITH ELECTRO-ACUPUNCTURE

44 cats were used in this experiment. The spinal cords of 40 animals were injuredat about L_1 level by using Allen's method (400g/cm) and randomly divided into 2 groups: A)electro-acupuncture treatment group (n=20) and B) control group(n=20). 2 weeks after spinalcord injury, 80% of animals in the treatment group were survival and 45% of animals in the con-trol group were survival. There was significant difference between these two groups (p<0. 05).The motor evoked potential was recorded two weeks after spinal cord injury. The latency of theshort latency peak was 15. 61±4. 98 mS and the amplitude was 10. 61 0. 59 mV in the treatmentgroup; and 21. 7±5. 02 mS and 0. 56±0. 32 mV in the control group. Both latency and amplitudewere significant different between the two groups (P<0. 05, P<0. 05). The Anti-NF-H (neuro-filament) was determined at 2 and 4 weeks respectively after spinal cord injury. The more NF-Hpositive labeling fibers were found in the treatment group than in the control group (P<0. 01 ).The     

麝香酮对氰化钠加缺糖致PC12细胞缺血损伤的保护作用

目的:研究麝香酮对PC12细胞缺血损伤的影响。方法:在离体培养的PC12细胞,用NaCN加缺糖造成拟缺血损伤模型,通过细胞形态学观察、MTT微量比色、培养介质LDH活力测定,研究了麝香酮对该模型的保护作用。结果:10-7~510-5mol/L范围内,麝香酮呈浓度依赖性地降低NaCN加缺糖造成拟缺血损伤模型培养介质内LDH的释放,其IC50为:43.33μmol/L。在10-7~510-5mol/L范围内,麝香酮呈浓度依赖性地增加NaCN加缺糖造成拟缺血损伤模型培养介质的MTT比色值,其IC50为30.62μmol/L。结论:麝香酮对PC12细胞缺血损伤具有保护作用。     

Hepatitis D: advances and challenges

Hepatitis D virus (HDV) infection causes the most severe form of viral hepatitis with rapid progression to cirrhosis, hepatic decompensation, and hepatocellular carcinoma. Although discovered > 40 years ago, little attention has been paid to this pathogen from both scientific and public communities. However, effectively combating hepatitis D requires advanced scientific knowledge and joint efforts from multi-stakeholders. In this review, we emphasized the recent advances in HDV virology, epid...     

氟尿嘧啶类联合奥沙利铂方案治疗晚期转移性小肠癌的临床效果

目的 评估临床采用氟尿嘧啶类药物联合奥沙利铂治疗晚期转移性小肠癌的临床效果及安全性.方法 回顾性分析近6年来于本院接受化学治疗的89例晚期小肠癌患者的一般资料,按照治疗方法的不同进行等均分组,其中45例患者采取FOLFOX(奥沙利铂、亚叶酸钙、氟尿嘧啶)治疗方案,纳入对照组,另外44名患者采取XELOX(奥沙利铂联合卡培他滨)方案,作为观察组.观察两组临床效果以及用药不良反应,并在随访过程中观察两组中位疾病进展时间.结果 观察组总有效率优于对照组(61.36％比55.55％),但组间差异无统计学意义(P＞0.05);观察组毒副反应发生率高于对照组(36.3％比31.1％),但差异无统计学意义(P＞0.05).结论 采用氟尿嘧啶类药物联合奥沙利铂治疗晚期转移性小肠癌安全有效,毒副反应可耐受,可作为不可手术切除或转移性小肠癌的一线化疗选择,但仍需要大量数据样本做进一步研究证实.     

建立中药材盲样检验机制 有效预防以权谋私

从建立管理制度、完善工作程序、编制作业文件、加强运行监督等方面介绍了药品检验机构新近运行的中药材盲样检验机制,详细介绍了中药材盲样检验工作流程,对中药材盲样检验机制在药品检验机构廉政建设中有效预防以权谋私的作用进行了简要论述。