对胃蛋白酶合剂处方组成与质控指标的研讨

本文介绍了胃蛋白酶合剂处方组成与质量标准控制项目的相互关系与影响，对《中国医院制剂规范》西药制剂第二版收载的胃蛋白酶合剂质量标准提出了合理化的建议。     

IFNγ防治大鼠胆总管结扎所致肝纤维化的实验研究

目的：了解IFNγ对持续肝外性淤胆所致肝纤维化的作用。方法：制作大鼠持续肝外性淤胆模型,用药组于胆管结扎同时每日肌注IFNγ 5×104 U,用药2周;对照组则仅行胆管结扎而不用药。2周后分别测定血清生化指标、肝纤维化指标及肝能量代谢有关指标。结果：IFNγ可改善血清生化指标(P＜0.01或P＜0.05)。在组织学表现上,用药组肝纤维化程度显著低于单纯结扎组(P＜0.01)。用药组大鼠淤胆后肝羟脯氨酸及血清透明质酸水平升高明显受抑(P＜0.01)。肝ATP及CP测定显示淤胆合并用药时两者均保持于较高水平。结论：IFNγ可有效抑制大鼠持续肝外性淤胆所致肝纤维化     

Synthesis,electronic structures,and photoluminescence properties of an efficient and thermally stable red-emitting phosphor Ca3ZrSi2O9:Eu3+,Bi3+ for deep UV-LEDs

A series of red-emitting Ca₃ZrSi₂O₉:Eu³⁺,xBi³⁺ phosphors was synthesized using a conventional high temperature solid-state reaction method, for the purpose of promoting the emission efficiency of Eu³⁺ in a Ca₃ZrSi₂O₉ host. The site preference of Bi³⁺ and Eu³⁺ in the Ca₃ZrSi₂O₉ host was evaluated by formation energy. The effects of Bi³⁺ on electronic structure, luminescent properties, and related mechanisms were investigated. The inner quantum yield of the optimized sample increased to 72.9% (x = 0.08) from 34.6% (x = 0) at 300 nm ultraviolet light excitation. The optimized sample (x = 0.08) also showed excellent thermal stability, and typically, 84.2% of the initial emission intensity was maintained when the temperature increased to 150 °C from 25 °C, which is much higher than that without Bi³⁺ doping (70.1%). The mechanisms of emission properties and thermal stability enhancement, as well as the redshift of the charge transfer band (CTB) induced by Bi³⁺ doping in the Ca₃ZrSi₂O₉:Eu³⁺ phosphor, were discussed. This study elucidates the photoluminescence properties of Bi³⁺-doped Ca₃ZrSi₂O₉:Eu³⁺ phosphor, and indicates that it is a promising luminescent material that can be used in ultraviolet light-emitting diodes.

A red-emitting phosphor Ca₃ZrSi₂O₉:Eu³⁺,Bi³⁺ with high quantum yield and thermal stability was developed by introducing Bi³⁺ as an efficient sensitizer.     

Synthesis of dimethyl carbonate from CO2 and methanol over a hydrophobic Ce/SBA-15 catalyst

A series of Ce/SBA-15 catalysts with different degrees of hydrophobicities were prepared via a post-grafting method and used for the direct synthesis of dimethyl carbonate (DMC) from CO₂ and methanol. The Ce/SBA-15-6 catalyst exhibited the highest DMC yield of 0.2%, which was close to the equilibrium value under the reaction conditions of 130 °C, 12 h and 12 MPa. The catalysts were characterized via XRD, BET, FT-IR, solid-state ²⁹Si MAS NMR, CA, TEM, XPS and NH₃/CO₂-TPD; the results indicated that the hydrophobicity of the catalysts facilitated the creation of oxygen vacancies, which could act as Lewis acids to activate methanol. Higher amounts of moderate acid sites led to higher yields of DMC. In addition, the hydrophobicity of the catalysts could also reduce the adsorbed water on their surface and increase the DMC yield while shortening the reaction time.

A series of Ce/SBA-15 catalysts with different degrees of hydrophobicities were prepared via a post-grafting method and used for the direct synthesis of dimethyl carbonate (DMC) from CO₂ and methanol.     

Geometric classification of the carotid siphon: association between geometry and stenoses

Purpose

The development of intracranial internal carotid artery (ICA) stenoses may be associated with the morphology of the siphon. The aim is to quantitatively characterize the geometry of ICA, and develop a classifier of the ICA shape in relation to the location and incidence of stenoses.

Methods

The ICA geometry from 74 subjects was analyzed by means of image-based computational techniques. The siphon was split into two bends, and was described in terms of curvature radius, radius of vessel, angle of bending, and length. Differences of geometry between ICA classes were assessed in control group, consisted of 30 subjects without stenoses. In stenosed group, the association between the ICA classes and the incidence of stenoses were investigated and validated by hemodynamic simulation.

Results

The curvature radius and angle of the posterior bend were significantly different between ICA classes, as well as the angle between the two bends. An innovative classifier was developed with the three geometric parameters. The ICA classification was found associated with the incidence of stenoses at the siphon.

Conclusions

Geometric factors relative to the ICA were correlated with the location and incidence of stenoses at the siphon. The present work has potential implications in the quest for hemodynamic factors contributing to the initiation and progression of intracranial ICA stenoses.     

Molecular characteristics and evolutionary analysis of field Marek’s disease virus prevalent in vaccinated chicken flocks in recent years in China

Marek’s disease is a highly contagious, oncogenic, and immunosuppressive avian viral disease. Surveillance of newly registered Marek’s disease virus (MDV) isolates is meaningful for revealing the potential factors involved in increased virulence. Presently, we have focused on the molecular characteristics of all available MDVs from China, including 17 new Henan isolates. Based on Meq, gE, and gI genes, we found that most Chinese isolates contain conserved amino acid point mutations in Meq, such as E⁷⁷, A¹¹⁵, A¹³⁹, R¹⁷⁶, and A²¹⁷, compared to USA virulent MDVs. However, the 59-aa or 60-aa insertions are only found in a few mild MDVs rather than virulent MDVs in China. Further phylogenetic analysis has demonstrated that a different genotype of MDV has been prevalent in China, and for virulent MDVs, their recent evolution has possibly been geographically restricted. Our study has provided more detailed information regarding the field MDVs circulating in China.     

Keggin‐Type Polyoxometalate ([PMo12O40]3−) in Radical Initiating Systems: Application to Radical and Cationic Photopolymerization Reactions

New photoinitiating systems based on a polyoxometalate (POM) are proposed: phosphomolybdic acid in combination with silane, germane, or iodonium salt can be used to generate silyl, germyl, or phenyl radicals as well as silylium cations. The photochemical mechanisms are studied by steady‐state photolysis and electron spin resonance. The phosphomolybdic acid/silane/iodonium salt system can initiate either the radical photopolymerization of acrylates or the cationic photopolymerization of epoxides. The synthesis of interpenetrated polymer networks can also be carried out. The mechanical properties of the synthesized polymers are affected by the presence of POM in the matrix, as shown by their dynamic mechanical analysis (DMA).