Bismuth Sodium Titanate Based Materials for Piezoelectric Actuators

The ban of lead in many electronic products and the expectation that, sooner or later, this ban will include the currently exempt piezoelectric ceramics based on Lead-Zirconate-Titanate has motivated many research groups to look for lead-free substitutes. After a short overview on different classes of lead-free piezoelectric ceramics with large strain, this review will focus on Bismuth-Sodium-Titanate and its solid solutions. These compounds exhibit extraordinarily high strain, due to a field induced phase transition, which makes them attractive for actuator applications. The structural features of these materials and the origin of the field-induced strain will be revised. Technologies for texturing, which increases the useable strain, will be introduced. Finally, the features that are relevant for the application of these materials in a multilayer design will be summarized.     

帕拉米韦注射液治疗儿童流感的临床疗效分析

目的探讨儿童流感应用帕拉米韦注射液治疗的临床疗效以及用药安全性。方法随机选定在2016年1月-2019年1月期间佛山市高明区人民医院儿科住院治疗并确诊流感A或B型患儿200例,通过随机数字法将其分为治疗组和对照组。治疗组100例用帕拉米韦注射液治疗,对照组100例用国产磷酸奥司他韦颗粒治疗,评价两组患儿治疗前后症状评分、治疗效果、治疗指标以及不良反应发生情况。结果两组患儿治疗前流感样症状评分无统计学意义(P>0.05),两组患儿治疗后较治疗前流感样症状评分均下降,差异有统计学意义(P<0.05);治疗组治疗后流感样症状评分略小于对照组,但是无统计学意义(P>0.05);治疗组治疗总有效率高于对照组,治疗组患儿发热症状缓解、全部症状缓解以及住院时间均小于对照组,存在统计学意义(P<0.05)。治疗组与对照组不良反应发生率较低,且无统计学意义(P>0.05)。结论帕拉米韦注射液可用于儿童流感治疗,不仅能够保证临床疗效,而且可加快症状缓解,同时存在较高用药安全性。     

Revisiting the Hydrogen Storage Behavior of the Na-O-H System

Solid-state reactions between sodium hydride and sodium hydroxide are unusual among hydride-hydroxide systems since hydrogen can be stored reversibly. In order to understand the relationship between hydrogen uptake/release properties and phase/structure evolution, the dehydrogenation and hydrogenation behavior of the Na-O-H system has been investigated in detail both ex- and in-situ. Simultaneous thermogravimetric-differential thermal analysis coupled to mass spectrometry (TG-DTA-MS) experiments of NaH-NaOH composites reveal two principal features: Firstly, an H₂ desorption event occurring between 240 and 380 °C and secondly an additional endothermic process at around 170 °C with no associated weight change. In-situ high-resolution synchrotron powder X-ray diffraction showed that NaOH appears to form a solid solution with NaH yielding a new cubic complex hydride phase below 200 °C. The Na-H-OH phase persists up to the maximum temperature of the in-situ diffraction experiment shortly before dehydrogenation occurs. The present work suggests that not only is the inter-phase synergic interaction of protic hydrogen (in NaOH) and hydridic hydrogen (in NaH) important in the dehydrogenation mechanism, but that also an intra-phase H^δ+… H^δ– interaction may be a crucial step in the desorption process.     

A facile synthesis of [14C]pyrithiobac‐sodium

Condensation of thiourea 1 with diethyl malonate 2 in the presence of sodium methoxide furnished 4,6‐dihydroxy‐2‐mercaptopyrimidine 3 . Compound 3 on methylation with diazomethane followed by oxidation with H₅IO₆/CrO₃ in ethyl acetate gave 4,6‐dimethoxy‐2‐methylsulphonylpyrimidine 5 . Compound 5 on condensation with 2‐mercapto‐6‐chlorobenzoic acid in the presence of a phase transfer catalyst, tetrabutylammonium bromide and sodium carbonate gave the title compound – pyrithiobac‐sodium 6 with an overall yield of > 35% starting from thiourea. Following the above standardized procedure, using [¹⁴C]‐thiourea in lieu of thiourea, ¹⁴C labelled product 6 , was synthesized with an overall radiochemical yield > 30% (with respect to [¹⁴C]‐thiourea) for further evaluations of environmental fate of 6 , in soils and plants. Copyright © 2006 John Wiley & Sons, Ltd.     

携载rhBMP-2微球的新型可注射自凝固复合人工骨的制备及特性研究

[目的]制备一种具有良好降解性和成骨活性、可注射的自凝固新型骨修复材料。[方法]制备携载rhBMP-2的聚乳酸与聚乙醇酸共聚物（PLGA）微球，并将其与rhBMP-2／磷酸钙骨水泥（CPC）复合，制备出rhBMP-2／PLGA微球／CPC复合人工骨。探讨了材料的特性，包括形貌、固化时间、抗压强度及反映材料体外降解速度的指标一体外降解液Ca、P浓度变化，测定复合材料rhBMP乏的释药速度及体外诱导MSCs细胞成骨分化的能力。[结果]与单纯CPC-rhBMP-2相比，复合材料的固化时间少量增加，抗压强度下降明显。体外降解速度及体外释药明显提高，释放的rhBMP-2具有骨诱导活性。[结论]rhBMP-2／PLGA微球／磷酸钙骨水泥新型复合人工骨是具有良好应用前景的骨修复材料。     

Ligustrazine inhibits high voltage-gated Ca~(2+) and TTX-resistant Na~+ channels of primary sensory neuron and thermal nociception in the rat:a study on peripheral mechanism

Objective Ligustrazine, also named as tetramethylpyrazine, is a compound purified from Ligusticum chuanxiong hort and has ever been testified to be a calcium antagonist. The present investigation was to determine the antinoci-ceptive effect of ligustrazine and, if any, the peripheral ionic mechanism involved. Methods Paw withdrawal Latency ( PWL) to noxious heating was measured in vivo and whole-cell patch recording was performed on small dorsal root ganglion (DRG) neurons. Results Intraplantar injection of ligustrazine (0.5 mg in 25μl) significantly prolonged the withdrawal latency of ipsilateral hindpaw to noxious heating in the rat. Ligustrazine not only reversibly inhibited high-voltage gated calcium current of dorsal root ganglion (DRG) neuron in dose-dependent manner with IC50 of 1.89 mmol/L, but also decreased tetrodotoxin (TTX) -resistant sodium current in relatively selective and dose-dependent manner with IC50 of 2.49 mmol/L. Conclusion The results suggested that ligustrazine could elevate the threshold of thermal nociception through inhibiting the high-voltage gated calcium current and TTX-resistant sodium current of DRG neuron in the rat.     

重度苯妥英钠中毒的药学监护

目的首先确定中毒药物,然后通过测定血药浓度以了解中毒程度,为重度苯妥英钠中毒患者临床抢救治疗提供依据。方法间隔一定时间采集患者静脉血,萃取血中药物,在211 nm处以反相高效液相色谱法定性,明确中毒药物并测定血药浓度。结果在苯妥英中毒患者中最高血药浓度为68.94 mg.L-1,接近治疗浓度上限的3.5倍。结论患者为重度中毒,危及生命,需临床药师与临床医师积极配合,施行全程药学监护。     

Blunted renal dopaminergic system activity in puromycin aminonucleoside-induced nephrotic syndrome.

BACKGROUND: A primary tubular sodium handling abnormality has been implicated in the edema formation of nephrotic syndrome. Dopamine synthesized by renal proximal tubules behaves as an endogenous natriuretic hormone by activating D(1)-like receptors as a paracrine/autocrine substance. METHODS: We examined the time courses of the urinary excretion of sodium, protein and dopamine in puromycin aminonucleoside (PAN)-treated and control rats. The rats were sacrificed during greatest sodium retention (day 7) as well as during negative sodium balance (day 14) for the evaluation of renal aromatic l-amino acid decarboxylase (AADC) activity, the enzyme responsible for the synthesis of renal dopamine. Also, the influence of volume expansion (VE) and the effects of the D(1)-like agonist fenoldopam (10 microg/kg bw/min) on natriuresis and on proximal tubular Na(+),K(+)-ATPase activity were examined on day 7. RESULTS: The daily urinary excretion of dopamine was decreased in PAN-treated rats, from day 5 and beyond. This was accompanied by a marked decrease in the renal AADC activity, on days 7 and 14. During VE, the fenoldopam-induced decrease in proximal tubular Na(+),K(+)-ATPase activity was more pronounced in PAN-treated rats than in controls. However, the urinary sodium excretion during fenoldopam infusion was markedly increased in control rats but was not altered in PAN-treated animals. CONCLUSION: PAN nephrosis is associated with a blunted renal dopaminergic system activity which may contribute to enhance the proximal tubular Na(+),K(+)-ATPase activity. However, the lack of renal dopamine appears not to be related with the overall renal sodium retention in a state of proteinuria.