Thermal Properties of Illite-Zeolite Mixtures up to 1100 °C

Illitic clays are the commonly used material in building ceramics. Zeolites are microporous, hydrated crystalline aluminosilicates, they are widely used due to their structure and absorption properties. In this study, illitic clay (Füzérradvány, Hungary) was mixed with natural zeolite (Nižný Hrabovec, Slovakia) with up to 50 wt.% of zeolite content. The samples were submitted to thermal analyses, such as differential thermal analysis, differential scanning calorimetry, thermogravimetry, and dilatometry. In addition, the evolution of thermal diffusivity, thermal conductivity, and specific heat capacity in the heating stage of firing were measured and discussed. The amount of the physically bound water in the samples increased along with the amount of zeolite. The temperature of the illite dehydroxylation (peak temperature) was slightly shifted to lower temperatures, from 609 °C to 575 °C (for sample IZ50). On the other hand, the mass loss and the shrinkage of the samples significantly increased with the zeolite content in the samples. Sample IZ50 reached 10.8% shrinkage, while the sample prepared only from the illitic clay contracted by 5.8%. Nevertheless, the temperature of the beginning of the sintering (taken from the dilatometric curves) decreased from 1021 °C (for illitic clay) to 1005 °C (for IZ50). The thermal diffusivity and thermal conductivity values decreased as the amount of zeolite increased in the samples, thus showing promising thermal insulating properties.     

二次经皮穿刺球囊压迫治疗初次球囊术后复发性三叉神经痛

目的探讨二次经皮穿刺球囊压迫(percutaneous balloon compression,PBC)治疗初次PBC术后复发性三叉神经痛的临床疗效。方法回顾性分析了64例采用二次PBC治疗初次PBC术后复发性三叉神经痛患者的临床资料及疗效。结果术后疼痛即刻缓58例(90.6%),偶有疼痛但不需服药者3例(4.7%),疼痛未消失但服药可控制者2例(3.1%),较术前有所缓解但服药不能控制者1例(1.6%),整体有效率为95.3%。随访至今(2~63个月,平均随访时间2年以上),6例轻度复发,2例重度复发,2年复发率12.5%。术后患侧面部麻木60例(93.8%),咀嚼肌乏力36例(56.3%),口角疱疹29例(45.3%),无角膜溃疡、蛛网膜出血及其他严重并发症。结论二次PBC治疗初次PBC术后复发的三叉神经痛具有风险小、疗效好、复发率低的优点,是其较理想手术方案选择。     

高血压脑出血早期控制血压对血肿扩大的影响?

目的：研究早期控制血压对高血压性脑出血患者血肿扩大的影响。方法对96例急性期高血压脑出血患者随机分为强化降压组(48例)和标准降压组(48例),分别予以强化降压及标准降压。两组入院时及入院24 h 查头颅 CT 及神经功能评分,然后对两组头颅 CT 血肿体积大小及神经缺损功能评分进行对比分析。结果入院后24 h 强化降压组较标准降压组神经功能评分明显降低(P <0.05),入院后24 h 复查头部 CT 发现,强化降压组和标准降压组入院24 h 血肿体积及血肿扩大发生率比较,差异有统计学意义(P <0.05)。结论高血压脑出血早期控制血压可降低血肿扩大,减少神经功能缺损症状。     

被动自锁托槽在固定正畸治疗中的应用

目的 通过比较被动自锁托槽与传统结扎托槽在非拔牙固定矫治的差异,来评估被动自锁托槽在固定正畸治疗中应用价值.方法 从已有病例中选取患者40例,其中Damon Q自锁托槽组20例,传统托槽组20例.比较两组患者治疗过程中及治疗前后牙周相关指数的变化、治疗前后扩弓效果,以及两组患者每组平均矫治疗程、平均就诊次数、每次复诊医...     

Studies on percutaneous transvenous mitral commissurotomy using a modified transseptal approach

Summary A modified version of Brockenbrough's trans-septal catheterization technique was carried out in 11 patients indicated for percutaneous transvenous mitral commissurotomy (PTMC). In 8/11 (72.7%), a coiled guide-wire was successfully inserted through theforamen ovale without atrial septal puncture. The Brockenbrough needle was used merely to maintain stiffness and the orientation of the dilator. PTMC was performed with an Inoue single balloon without incident.Patent foramen ovale was found by transesophageal echocardiography prior to the operation in only 1/11 patients (9.0%); nonetheless, it proved not to be a critical factor for the success of the procedure. This procedure seems to have much potential to enable the treatment of mitral stenosis with a lowered risk to the patient, as long as it is performed with precision and caution.     

On the evolution of chaperones and cochaperones and the expansion of proteomes across the Tree of Life

Across the Tree of Life (ToL), the complexity of proteomes varies widely. Our systematic analysis depicts that from the simplest archaea to mammals, the total number of proteins per proteome expanded ∼200-fold. Individual proteins also became larger, and multidomain proteins expanded ∼50-fold. Apart from duplication and divergence of existing proteins, completely new proteins were born. Along the ToL, the number of different folds expanded ∼5-fold and fold combinations ∼20-fold. Proteins prone to misfolding and aggregation, such as repeat and beta-rich proteins, proliferated ∼600-fold and, accordingly, proteins predicted as aggregation-prone became 6-fold more frequent in mammalian compared with bacterial proteomes. To control the quality of these expanding proteomes, core chaperones, ranging from heat shock proteins 20 (HSP20s) that prevent aggregation to HSP60, HSP70, HSP90, and HSP100 acting as adenosine triphosphate (ATP)-fueled unfolding and refolding machines, also evolved. However, these core chaperones were already available in prokaryotes, and they comprise ∼0.3% of all genes from archaea to mammals. This challenge—roughly the same number of core chaperones supporting a massive expansion of proteomes—was met by 1) elevation of messenger RNA (mRNA) and protein abundances of the ancient generalist core chaperones in the cell, and 2) continuous emergence of new substrate-binding and nucleotide-exchange factor cochaperones that function cooperatively with core chaperones as a network.

All cellular life is thought to have stemmed from the last universal common ancestor (LUCA) (1, 2), that emerged more than 3.6 billion y ago. Two major kingdoms of life diverged from LUCA: bacteria and archaea, which about 2 billion y later merged into the eukaryotes (3). Since the beginning of biological evolution, life’s volume has increased on a grand scale: The average size of individual cells has increased ∼100-fold from prokaryotes to eukaryotes (4), the number of cell types has increased ∼200-fold from unicellular eukaryotes to humans (5), and average body size has increased ∼5,000-fold from the simplest sponges to blue whales (6).This expansion in organismal complexity and variability was accompanied by an expansion in life’s molecular workforce, proteomes in particular, which in turn presented a challenge of reaching and maintaining properly folded and functional proteomes. Most proteins must fold to their native structure in order to function, and their folding is largely imprinted in their primary amino acid sequence (7–9). However, many proteins, and especially large multidomain polypeptides, or certain protein types such as all-beta or repeat proteins, tend to misfold and aggregate into inactive species that may also be toxic (10). Life met this challenge by evolving molecular chaperones that can minimize protein misfolding and aggregation, even under stressful out-of-equilibrium conditions favoring aggregation (11, 12). Chaperones can be broadly divided into core and cochaperones. Core chaperones can function on their own, and include ATPases heat shock protein 60 (HSP60), HSP70, HSP100, and HSP90 and the adenosine triphosphate (ATP)-independent HSP20. The basal protein holding, unfolding, and refolding activities of the core chaperones are facilitated and modulated by a range of cochaperones such as J-domain proteins (13–15).Starting from LUCA, as proteomes expanded, so did the core chaperones and their respective cochaperones. Indeed, chaperones have been shown to facilitate the acquisition of destabilizing mutations and thereby accelerate protein evolution (16–18). However, the coexpansion of proteomes and of chaperones, underscoring a critical balance between evolutionary innovation and foldability, remains largely unexplored. We thus embarked on a systematic bioinformatics analysis that explores the evolution of both proteomes and chaperones, and of both core and their auxiliary cochaperones, along the Tree of Life.     

Prolonged ex vivo culture of cord blood CD34(+) cells facilitates myeloid and megakaryocytic engraftment in the non-obese diabetic severe combined immunodeficient mouse model

A clinical goal for ex vivo expansion of cord blood (CB) CD34(+) cells is to shorten the period of neutropenia and thrombocytopenia following myeloablative therapy and transplantation. Prolongation of cytokine expansion leads to the production of greater numbers of cells, and should have an impact on neutrophil and platelet recovery. Furthermore, expansion of CD34(+) cells should support the continued production of neutrophils and platelets in the 6-week period following transplantation. We tested these hypotheses by characterization of the kinetics (human CD45(+) cells in the blood) and phenotype (CD45, CD34, CD61, CD33, CD19 and CD3) of human engraftment in the non-obese diabetic severe combined immunodeficient mouse (NOD-SCID) following 7 or 14 d of ex vivo expansion of CB CD34(+) cells. Mice transplanted with 14 d cells showed greater percentages of human CD45(+) cells in the blood, bone marrow and spleen than mice transplanted with unexpanded cells or 7 d cells. Prolonging cytokine exposure of CD34(+) cells and transplantation with increasing numbers of input cells facilitated the production of absolute numbers of CD34(+), CD33(+), CD61(+) and CD19(+) cells in vivo. Furthermore, analysis of SCID engrafting potential showed that prolongation of culture duration facilitates in vivo expansion of CD45(+), CD34(+) and CD19(+) cells after transplantation. It is anticipated that prolonged (2 weeks) ex vivo culture of CB will have a beneficial clinical effect.     

“支柱块”置入与球囊扩张椎体后凸成形术治疗老年胸腰椎压缩骨折的疗效观察

目的分析"支柱块"置入与球囊扩张椎体后凸成形方法在老年胸腰椎压缩骨折患者治疗中的效果。方法将2012年1月~2013年6月期间150例老年胸腰椎压缩骨折患者依据随机数字表法分为两组,实验组使用"支柱块"置入治疗,对照组采用球囊扩张椎体后凸成形术治疗,观察两组效果。结果实验组与对照组手术时间、失血量之间比较差异有统计学意义(P<0.05)。实验组24 h疼痛目测类评分高于对照组,差异有统计学意义(P<0.05)。结论 "支柱块"置入与球囊扩张椎体后凸成形方法均对老年胸腰椎压缩骨折患者的影响小,且二者各具优点,依据患者具体状况进行选择。     

Percutaneous Papillary Large Balloon Dilation during Percutaneous Cholangioscopic Lithotripsy for the Treatment of Large Bile-Duct Stones: A Feasibility Study

When access to a major duodenal papilla or endoscopic retrograde cholangiopancreatography has failed, percutaneous transhepatic cholangioscopic lithotripsy (PTCS-L) may be useful for removing common bile duct (CBD) stones. However, the feasibility and usefulness of percutaneous transhepatic papillary large-balloon dilation (PPLBD) during PTCS-L for the removal of large CBD stones has not been established. We aimed to determine the safety and efficacy of PPLBD for the treatment of large CBD stones. Eleven patients with large CBD stones in whom the access to the major papilla or bile duct had failed were enrolled prospectively. Papillary dilation was performed using a large (12-20 mm) dilation balloon catheter via the percutaneous transhepatic route. Post-procedure adverse events and efficacy of the stone retrieval were measured. The initial success rate of PPLBD was 100%. No patient required a basket to remove a stone after PPLBD. Electrohydraulic lithotripsy was required in 2 (18.2%) patients. The median time to complete stone removal after PPLBD was 17.8 min and no adverse events occurred after PPLBD. Asymptomatic hyperamylasemia was not encountered in any patients. This study indicates that PPLBD is safe and effective for removal of large CBD stones.

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