种植牙用钛合金Ti-30Nb-8Zr-2Mo硬度及弹性模量

背景：目前广泛应用于临床的纯钛和Ti-6Al-4V种植体材料中存在着铝和钒的潜在毒性及弹性模量太大易造成界面应力屏障等问题。目的：对自行研制的新型钛合金Ti-30Nb-8Zr-2Mo进行硬度及弹性模量性能测试。设计、时间及地点：观察实验,于2003-03/2006-02在河北工业大学材料学实验室完成。材料：钛合金制备用原材料海绵钛纯度≥99%、钼粉纯度≥ 99%、铌条≥ 99.9%、海绵锆≥ 99.4%。方法：在均匀化退火、热煅、固溶后对试样显微硬度进行测量,对时效后的样品进行压缩试验。主要观察指标：硬度值和应力应变曲线。结果：研究显示800 ℃ 0.5 h固溶后得到最大程度的强化合金,固熔合金硬度变化不大,时效后硬度显著增强,试样的抗压强度为 1 054 MPa,压缩弹性模量达到16.5 GPa。结论：自行研制的新型钛合金Ti-30Nb-8Zr-2Mo硬度和弹性模量均达到种植体材料的性能要求。     

湿法混合制粒法制备碳酸氢钠片

目的研究以湿法混合制粒法制备碳酸氢钠片的工艺。方法采用淀粉、糊精、蔗糖粉为辅料,以不同配比、不同工艺制备碳酸氢钠片,并用正交设计筛选出了最佳制备工艺参数。结果经过片剂硬度测试证明,淀粉-糊精-蔗糖粉的配比为7∶1∶1,在制粒时加入5%的淀粉浆,压片时厚度控制为4.30mm时所压的片剂硬度最好。讨论A1B2C1配方及工艺得到的片剂硬度较好,适于生产,但没有考虑崩解时限、溶出度等指标。     

Influence of Plasticizer Type and Coat Level on Surelease® Film Properties

Two commercially available formulations of aqueous ethylcellulose dispersion differing in their plasticizer, i.e., Surelease/E-7-7050 containing dibutyl sebacate (DBS) and Surelease/E-7-7060 containing glyceryl tricaprylate/caprate (GTC), were evaluated and compared for their film properties as a function of polymeric coat level. Ibuprofen tablets were coated at 1, 2, 3, and 5% w/w levels using each Surelease formulation, and the coated tablets were evaluated for their drug release characteristics, coat reflectivity (gloss), surface texture, Brinell hardness, and elastic modulus. The drug release was dependent on the coat level and followed Hixson–Crowell cube-root model at 1% coat level. However, at ≥2% coat levels, the release from tablets coated with GTC plasticized formulation appeared to be best described by non-Fickian release mechanism and that from tablets coated with DBS plasticized formulation appeared to follow apparent zero-order release mechanism. At equal coat levels, tablets coated with GTC plasticized Surelease yielded lower drug release rates, higher reflectivity (gloss), lower surface roughness, higher Brinell hardness, and lower elastic modulus than those coated with DBS plasticized formulation. A good correlation was observed between the drug release rates and the reflectivity and surface texture of the coated tablets. The film-coats of GTC plasticized formulation were harder and more elastic than those of DBS plasticized formulation indicating better mechanical integrity.     

七种光固化复合树脂冷热循环后机械性能评价(英文)

目的研究7种不同的光复合树脂热循环试验后的机械性能,探讨各性能之间的关系。方法将每种树脂(A110:AH、ESTELITE∑:ET、AELITE:AT、Z250:ZS、CharmFil plus:CP、Z350:ZH、Grandio:GD,其中AH、ET为微充填复合树脂,AT、ZS、CP为混合型复合树脂,ZH、GD为纳米型复合树脂)制成直径为12 mm,厚度为1.0 mm的实验样本。所得样本在37℃的蒸馏水中浸泡24 h,然后在5℃和55℃下间隔15 s冷热循环1 000次。应用尖端速率为0.5 mm/min的双轴挠曲强度试验测量材料的强度值(ISO4049),所得数据采用Weibull和ANOVA统计学分析。样本断面经扫描电镜观察,剩余样本碎片经Knoop硬度试验测试(负载50 g,时间10 s)。结果最高和最低的Weibull系数值分别出现在AH(18.752)和AT(5.290)组,最高和最低的双轴挠曲强度值分别出现在ZS(158.2MPa)和ET(54.0 MPa)组。不同填料的强度值大小依次为混合型复合树脂>纳米型复合树脂>微充填复合树脂,具有相同类型填料的复合树脂之间的强度值差异没有统计学意义(P>0.05),且强度试验所得碎片的数量与材料强度大小成正相关。GD组的硬度值最大(110.81±14.77)kg/mm2,AH组平均硬度值最小(42.81±1.91)kg/mm2,复合树脂的强度值与硬度值成正相关。扫描电镜观察显示树脂基质和填料之间是裂痕形成的薄弱部位。结论纳米型复合树脂比混合型复合树脂更适于临床应用。Knoop硬度实验是否适用于复合树脂材料的硬度测量还需要进一步证实。     

复方鳖甲软肝片联合苯扎贝特治疗胆汁性肝硬化的临床研究

目的探讨复方鳖甲软肝片联合苯扎贝特片治疗胆汁性肝硬化的临床疗效。方法选取2019年7月—2021年1月郑州人民医院收治的92例胆汁性肝硬化患者作为研究对象,按照随机数字表法将所有患者分为对照组和治疗组,各46例。对照组口服苯扎贝特片,200 mg/次,2次/d。治疗组在对照组治疗的基础上口服复方鳖甲软肝片,2.0 g/次,3次/d。两组患者连续治疗6个月。观察两组患者临床疗效,比较两组肝脏弹力硬度值、肝功能指标、肝纤维化指标。结果治疗后,治疗组的总有效率为93.48%,对照组的总有效率为78.26%,组间有明显差异(P0.05)。治疗后,两组患者肝脏弹力硬度值明显降低(P0.05),治疗组肝脏弹力硬度值比对照组降低更明显(P0.05)。治疗后,两组的谷氨酰转肽酶(GGT)、碱性磷酸酶(ALP)、总胆红素(TBIL)水平显著降低,差异有统计学意义(P0.05);治疗组GGT、ALP、TBIL水平降低更明显,差异有统计学意义(P0.05)。治疗后,两组的转化生长因子-β1(TGF-β1)、层黏连蛋白(LN)、Ⅲ型前胶原(PCⅢ)水平明显降低(P0.05);治疗组的TGF-β1、LN、PCⅢ水平低于对照组,差异有统计学意义(P0.05)。结论复方鳖甲软肝片联合苯扎贝特片治疗胆汁性肝硬化的疗效确切,能延缓肝纤维化进程,改善肝功能,减轻肝硬化程度,安全性较好。     

肝硬化的超声相关分析

利用M型超声技术检测肝脏在大血管搏动的激励下所产生的运动;这种运动的信息可以反映肝脏硬化的程度。本文先计算M型超声图像两列波形间的相关系数;然后对一个心动周期内的相关系数进行傅里叶分析,从中提取特性参数。在对正常肝脏和肝硬化情况进行分析后,得出了区分这两种肝脏状况的敏感参数及其范围。     

ICON渗透树脂修复人工釉质龋白斑的效果研究

目的：评价ICON渗透树脂修复人工釉质龋白斑的效果。方法：选取因正畸而拔除的前磨牙28颗,制备人工釉质龋后,随机分为实验组和对照组,实验组采用ICON渗透树脂修复人工釉质龋白斑,对照组采用涂氟处理,测量并比较釉质龋白斑修复后的表面微硬度和龋白斑面积减少百分比,最后采用SPSS17．0软件进行统计分析。结果：治疗修复后实验组釉质龋的表面微硬度值显著高于对照组,差异具有统计学意义（P＜0．05）;修复后实验组龋白斑所占面积百分比低于对照组,差异具有统计学意义（P＜0．05）。结论：ICON渗透树脂能提高人工釉质龋白斑表面的微硬度,并能大大降低龋白斑的面积百分比,推荐临床使用。     

First report on the association of drinking water hardness and endothelial function in children and adolescents

Introduction

This study aims to investigate the relationship of water hardness and its calcium and magnesium content with endothelial function in a population-based sample of healthy children and adolescents.

Material and methods

This case-control study was conducted in 2012 among 90 individuals living in two areas with moderate and high water hardness in Isfahan County, Iran. The flow-mediated dilatation (FMD) of the brachial artery and the serum levels of soluble adhesion molecules (sICAM-1, sVCAM-1) were measured as surrogate markers of endothelial function, and high-sensitivity C-reactive protein (hs-CRP), as a marker of inflammation.

Results

Data of 89 participants (51% boys, mean age 14.75 (2.9) years) were complete. Those participants living in the area with high water hardness had higher FMD, hs-CRP, and soluble adhesion molecules (sICAM-1, sVCAM-1) than their counterparts living in the area with moderate water hardness. Multiple linear regression analysis showed that after adjustment for confounding factors of age, gender, body mass index, healthy eating index and physical activity level, total water hardness, as well as water content of calcium and magnesium, had a significant positive relationship with FMD. The corresponding associations were inverse and significant with soluble adhesion molecules (p < 0.05).

Conclusions

This study, which to the best of our knowledge is the first of its kind in the pediatric age group, suggests that water hardness, as well as its calcium and magnesium content, may have a protective role against early stages of atherosclerosis in children and adolescents.     

Development of multiple-unit pellet system tablets by employing the SeDeM expert diagram system II: pellets containing different active pharmaceutical ingredients

The SeDeM Expert Diagram System (SeDeM EDS) was originally developed to provide information about the suitability of powders to produce direct compressible tablets. Multiple-unit pellet systems (MUPS) are dosage forms consisting of pellets compressed into tablets or loaded into hard gelatin capsules. The aim of this study was to apply the SeDeM EDS to different size pellets (i.e. 0.5, 1.0, 1.5, 2.0, and 2.5?mm) containing different APIs (i.e. doxylamine, ibuprofen or paracetamol) to determine which properties should be corrected to yield MUPS tablet formulations. The SeDeM parameter tests were conducted on the pellets, selected excipients, intermediate blends, and final blends. The study showed that the properties of the pellets depended on the active ingredient and pellet size. The SeDeM compressibility indices indicated that the final pellet blends should be suitable for compression into MUPS tablets. MUPS tablets were prepared from the final blends and evaluated in terms of physico-chemical properties and dissolution profiles. Only three of the MUPS tablet formulations containing ibuprofen and one MUPS tablet formulation containing paracetamol failed content uniformity. The water solubility of the APIs as well as the pellet size (surface area exposed to the dissolution medium) attributed to the difference in drug dissolution rate.