注射用华蟾素对大鼠心率及心电图的影响

目的观察注射用华蟾素对大鼠心率及心电图的影响,为该药在临床应用时监控心脏的不良反应提供实验依据。 方法大鼠经颈外静脉插管后恒速蠕动泵给药,标准肢体Ⅱ导联监测大鼠的心率及心电图;比较给药前后心率及心电图的变化。 结果静脉注射华蟾素注射液与注射用华蟾素中、大剂量30 min后均可使大鼠心率加快,分别为:(469±40),(466±29) 和(484±40)次·min-1,与空白对照组[(411±17)次·min-1]比较,差异有统计学意义(P＜0.05),但随后恢复正常。少数大鼠可偶致心律失常(期前收缩、传导阻滞等),且相比于空白对照组[P-R间期:(46.90±3.90) ms,Q-T间期:(61.29±9.46) ms],给药后能明显缩短心电图的P-R间期[华蟾素注射液组(39.70±2.54) ms,注射用华蟾素中剂量组(37.70±3.77) ms,注射用华蟾素大剂量组(39.30±7.12) ms]和Q-T间期[注射用华蟾素中剂量组(55.13±4.67) ms,注射用华蟾素大剂量组(51.75±11.53) ms](P＜0.05),而对QRS与S-T段无明显改变。 结论注射用华蟾素对大鼠心脏有一定的毒副作用,可引起心率加快,偶发心律失常。     

蔡光先教授运用五味异功散合过敏煎治疗小儿过敏性疾病验案举隅

蔡光先系国家级名中医,第五批全国名老中医药专家学术经验继承工作指导老师,博士研究生导师,国家有突出贡献专家,从事中医药教学、科研及临床工作40余载,擅长内科疑难杂症的诊治,临床经验丰富,学术造诣颇深,笔者有幸跟师临证学习,受益匪浅.现择其运用五味异功散合过敏煎治疗小儿过敏性疾病验案3则报道如下,以飨同道.     

双歧三联活菌联合蒙脱石散治疗小儿急性腹泻疗效观察

目的：探讨双歧三联活菌联合蒙脱石散治疗急性腹泻对患儿排便次数及症状改善的影响。方法选择2012年8月至2013年8月在我院接受治疗的急性腹泻患儿132例作为研究对象。根据随机数表法将患儿分成观察组和对照组各66例。对照组患儿给予蒙脱石散治疗,观察组在此基础上采用双歧三联活菌进行治疗。比较两组患儿治疗前后的腹泻排便次数、疗效以及症状改善情况。结果观察组患儿治疗后5d的腹泻排便次数明显少于对照组,差异有统计学意义(P<0.05);观察组患儿的显效率和总有效率分别为65.15%,98.48%,均明显高于对照组的45.45%,86.36%,差异均有统计学意义(P<0.05);观察组患儿的腹痛消失时间、呕吐消失时间、退热时间及大便常规的正常时间均少于对照组,差异均有显著统计学意义(P<0.01)。结论双歧三联活菌与蒙脱石散联合治疗小儿急性腹泻可明显减少患儿排便次数,改善其临床症状,疗效明显,值得临床上推广应用。     

Fundamental Improvement of Creep Resistance of New-Generation Nano-Oxide Strengthened Alloys via Hot Rotary Swaging Consolidation

New-generation oxide dispersion-strengthened (ODS) alloys with a high volume fraction of nano-oxides of 5% are intended to become the leading creep- and oxidation-resistant alloys for applications at 1100–1300 °C. Hot consolidation of mechanically alloyed powders by intensive plastic deformation followed by heat treatment of the alloys are the key aspects for achieving top creep properties, typically ensured by a coarse-grained microstructure strengthened with homogeneously dispersed, very stable yttrium nano-oxides. The rotary swaging method proves to be favourable for hot consolidation of the new-generation ODS alloy presented. Compared to specimens consolidated by hot rolling, consolidation by hot rotary swaging predetermines the formation of coarse grains with a very high aspect ratio during subsequent secondary recrystallization. Such a grain morphology increases the creep strength of the new-generation ODS alloy considerably.     

Resistance to Ultraviolet Aging of Nano-SiO2 and Rubber Powder Compound Modified Asphalt

Ultraviolet (UV) aging degrades the life span of asphalt pavement, nanomaterials used as modifiers exhibit good shielding function on UV light, but generally degrade the low-temperature property of asphalt, a compound modification was found to be a solution. In this study, nano-SiO₂ and rubber powder were blended together with base asphalt to prepare compound modified asphalt. Compound modified asphalt with different blending dosages were subjected to UV light via a self-made UV aging simulation chamber. Basic performance tests and rheological tests were conducted including the UV aging influence. An optimum compound ratio was finally recommended based on the goal to remove the adverse effect of nano-SiO₂ on the thermal cracking. Results show that the anti-UV aging property of asphalt is improved obviously due to the blocking function of nano-SiO₂ and carbon black in rubber powder, and the enhancing effect of nano-SiO₂ is found to be the most significant.     

Hot Deformation Behavior and Workability of In-Situ TiB2/7050Al Composites Fabricated by Powder Metallurgy

Isothermal compression tests of in-situ TiB₂/7050Al composites fabricated by powder metallurgy were performed at 300–460 °C with the strain rate varying from 0.001 s⁻¹ to 1 s⁻¹. The Arrhenius constitutive equation and hot processing map of composites were established, presenting excellent hot workability with low activation energies and broad processing windows. Dramatic discontinuous/continuous dynamic recrystallization (DDRX/CDRX) and grain boundary sliding (GBS) take place in composites during deformation, depending on the Zener-Hollomon parameter (Z) values. It is found that initially uniform TiB₂ particles and fine grain structures are beneficial to the DDRX, which is the major softening mechanism in composites at high Z values. With the Z value decreasing, dynamic recovery and CDRX around particles are enhanced, preventing the occurrence of DDRX. In addition, fine grain structures in composites are stable at elevated temperature thanks to the pinning of dense nanoparticles, which triggers the occurrence of GBS and ensures good workability at low Z values.     

Fabrication of Metallic Biomedical Scaffolds with the Space Holder Method: A Review

Bone tissue engineering has been increasingly studied as an alternative approach to bone defect reconstruction. In this approach, new bone cells are stimulated to grow and heal the defect with the aid of a scaffold that serves as a medium for bone cell formation and growth. Scaffolds made of metallic materials have preferably been chosen for bone tissue engineering applications where load-bearing capacities are required, considering the superior mechanical properties possessed by this type of materials to those of polymeric and ceramic materials. The space holder method has been recognized as one of the viable methods for the fabrication of metallic biomedical scaffolds. In this method, temporary powder particles, namely space holder, are devised as a pore former for scaffolds. In general, the whole scaffold fabrication process with the space holder method can be divided into four main steps: (i) mixing of metal matrix powder and space-holding particles; (ii) compaction of granular materials; (iii) removal of space-holding particles; (iv) sintering of porous scaffold preform. In this review, detailed procedures in each of these steps are presented. Technical challenges encountered during scaffold fabrication with this specific method are addressed. In conclusion, strategies are yet to be developed to address problematic issues raised, such as powder segregation, pore inhomogeneity, distortion of pore sizes and shape, uncontrolled shrinkage and contamination.     

延胡索、乌药、金铃子散、小活络丹对神经病理性疼痛镇痛作用的比较

目的：比较延胡索、乌药、金铃子散、小活络丹对坐骨神经缩窄性损伤（chronic constriction injury,CCI）模型大鼠神经病理性疼痛（neuropathic pain,NP）的镇痛效果。方法：将SD 雄性大鼠随机分为假手术组（n=13）、生理盐水组（n=13）、延胡索组（n=16）、乌药组（n=10）、金铃子散组（n=20）、小活络丹组（n=7）,共6 组。采用坐骨神经结扎法造模,于造模后第4 天各组给予相应的药物（延胡索组、乌药组、金铃子散组、小活络丹组大鼠均按剂量12 g·kg-1 给药,假手术组、生理盐水组给予等量生理盐水）灌胃,连续14 天。从开始给药起,每隔1 天测定其热痛阈值。结果：与生理盐水组比较,延胡索、乌药、金铃子散、小活络丹各组大鼠给药后热痛阈值均升高,金铃子散的效果稍微优于延胡索,乌药、小活络丹效果较差。结论：延胡索、乌药、金铃子散、小活络丹对神经病理性疼痛均具有一定的镇痛作用,其中金铃子散的镇痛作用较强且起效快,其次为延胡索,乌药和小活络丹对该种神经病理性疼痛的镇痛效果较不稳定。     

天麻指纹图谱的研究进展

天麻是我国名贵的中草药,随着近年来其商品的多样化,掺伪、假冒品不断增多,对其进行更全面、系统的质量控制尤为重要。目前,指纹图谱已成为国际公认的控制中药质量的有效手段之一,主要的研究方法有液相色谱法、薄层色谱法、毛细管电泳色谱、红外光谱、核磁共振、X射线粉末衍射、分子生物学指纹图谱和电化学指纹图谱等,本文对近年来天麻指纹图谱的研究情况进行了归纳总结,为进一步建立该药的质量控制提供了方法和依据。