对黏连性肠梗阻患者术后实施综合护理干预后的护理质量评价

目的探讨对黏连性肠梗阻患者术后实施综合护理干预后的护理质量。方法选取2014年1月至2014年12月期间在湖北省团风县人民医院接受治疗的腹部手术患者100例,将患者随机分为观察组与对照组,每组患者50例。其中对照组实施常规护理,观察组实施综合护理干预,比较两组患者的临床护理效果。结果观察组患者黏连性肠梗阻发生率低于对照组,胃肠道功能的恢复时间均短于对照组,组间比较差异具有统计学意义(P0.05)。结论腹部手术患者术后实施综合护理干预可减轻对胃肠道功能的影响,降低黏连性肠梗阻的发生几率。     

Nanomechanics of Poly(catecholamine) Coatings in Aqueous Solutions

Mussel‐inspired self‐polymerized catecholamine coatings have been widely utilized as a versatile coating strategy that can be applied to a variety of substrates. For the first time, nanomechanical measurements and an evaluation of the contribution of primary amine groups to poly(catecholamine) coatings have been conducted using a surface‐forces apparatus. The adhesive strength between the poly(catecholamine) layers is 30‐times higher than that of a poly(catechol) coating. The origin of the strong attraction between the poly(catecholamine) layers is probably due to surface salt displacement by the primary amine, π–π stacking (the quadrupole–quadrupole interaction of indolic crosslinks), and cation–π interactions (the monopole–quadrupole interaction between positively charged amine groups and the indolic crosslinks). The contribution of the primary amine group to the catecholamine coating is vital for the design and development of mussel‐inspired catechol‐based coating materials.     

Development of Non‐Cell Adhesive Vascular Grafts Using Supramolecular Building Blocks

Cell‐free approaches to in situ tissue engineering require materials that are mechanically stable and are able to control cell‐adhesive behavior upon implantation. Here, the development of mechanically stable grafts with non‐cell adhesive properties via a mix‐and‐match approach using ureido‐pyrimidinone (UPy)‐modified supramolecular polymers is reported. Cell adhesion is prevented in vitro through mixing of end‐functionalized or chain‐extended UPy‐polycaprolactone (UPy‐PCL or CE‐UPy‐PCL, respectively) with end‐functionalized UPy‐poly(ethylene glycol) (UPy‐PEG) at a ratio of 90:10. Further characterization reveals intimate mixing behavior of UPy‐PCL with UPy‐PEG, but poor mechanical properties, whereas CE‐UPy‐PCL scaffolds are mechanically stable. As a proof‐of‐concept for the use of non‐cell adhesive supramolecular materials in vivo, electrospun vascular scaffolds are applied in an aortic interposition rat model, showing reduced cell infiltration in the presence of only 10% of UPy‐PEG. Together, these results provide the first steps toward advanced supramolecular biomaterials for in situ vascular tissue engineering with control over selective cell capturing.

     

Application of the Scanning Kelvin Probe for the study of the corrosion resistance of interfacial thin organosilane films at adhesive/metal interfaces

The Scanning Kelvin Probe is introduced as a real time non-destructive in situ technique for the detection of de-adhesion at adhesive/metal oxide interfaces. Iron substrates and an epoxy adhesive served as model systems. Iron surfaces were coated with ultra-thin organosilane plasma polymer films from a microwave discharge and 3-(trimethoxysilyl)-propylamine films from dilute water based solutions. Surface and film characterisation was done by means of atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and infrared reflection absorption spectroscopy (IRRAS). The effect of these interfacial films on the stability of the adhesive/metal joint was studied in corrosive environments. The Scanning Kelvin Probe allows the measurement of electrode potentials at buried polymer/metal interfaces with a spatial resolution of about 100 m. The electrode potential characterises the reactivity of the interface. Moreover, by the variation of the oxygen partial pressure in the measurement chamber, local anodes and cathodes underneath the polymer can be distinguished. The kinetics of electrochemical de-adhesion can be effectively slowed down by thin 3-(trimethoxysilyl)-propylamine films at the interface. The effect of the adhesion promoter can be further improved when a thin SiO_x layer, which inhibits electron transfer reactions, and is deposited on the iron surface prior to coating with the adhesion promoter.This paper is dedicated to Mike Owen on occasion of his winning the DeBruyn medal, the first silicon chemist to do so.     

聚氨酯胶粘剂的热分解动力学研究

采用热分析技术考察了通用型聚氨酯胶粘剂在空气中的热解过程, 并通过TG方法和动力学方法研究了各步反应的活化能E、指前因子A等动力学参数. 通过等失重转化率法校验了两种方法所获得的E和A值. 结果表明, 聚氨酯胶粘剂有三个主要降解阶段, 第一降解阶段的活化能为144.31-148.35 kJ·mol^-1, 第二个降解阶段的活化能为196.96-204.26 kJ·mol^-1, 第三个降解阶段的活化能为202.97-205.27 kJ·mol^-1; 热降解过程为一级反应, 随着失重百分率的增大, 热分解反应活化能增大. 此外, 聚氨酯胶粘剂具有较高的热稳定性, 预测其在35 ℃的空气中失重5%时的热老化寿命为10年.     

Synthesis of unsaturated 7,8- and 7,9-di(hydroxymethyl)decahydro-7,8- and-7,9-dicarba-nido-undecaborate(1−) diethers

Dicarba-nido-undecaborate(1–) anions were obtained by treatment of 1,2-di(hydroxymethyl)-1,2-dicarba-closo-dodecaborane(12) diallyl ether, 1,2-di(hydroxymethyl)-1,2-dicarba-closo-dodecaborane (12), and 1,7-di(hydroxymethyl)-1,7-dicarba-closo-dodecaborane(12) with ethanolic solutions of KOH and subsequent reaction of the products with cesium and tetramethylammonium chlorides.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1821–1823, September, 1995.     

Asymptotic behavior of correlation functions for electric potential and field fluctuations in a classical one- component plasma

The correlations of the electric potential fluctuations in a classical one-component plasma are studied for large distances between the observation points. The two-point correlation function for these fluctuations is known to decay slowly for large distances, even if exponential clustering holds for the charge correlation functions. In this paper the asymptotic behavior of the generalk-point electric potential correlation functions is analyzed. Each of these correlation functions can be split into a reducible part, which is given by a sum of products of lower-order correlation functions, and a remaining irreducible part. It is shown, on the basis of an exponential clustering hypothesis for the charge correlation functions, that for allk3 the irreducible parts of the electric potential correlation functions decay faster than any inverse power of the distance, if one or more of the observation points move far away from the others. Hence, the two-point electric potential correlation function is the only one with a slow algebraic decay. The same statement holds for the correlation functions of the electric field fluctuations.     

Deposition of Ethylene-Hexafluoropropene Gradient Plasma-Copolymer Using Dielectric Barrier Discharge Reactor at Atmospheric Pressure: Application to Release Coatings on Pressure-Sensitive Tape

Plasma-polymerized hexafluoropropene (PPHFP) film deposited using a dielectric barrier discharge reactor at atmospheric pressure had low enough adhesive strength, 22.2 Nm^–1, for use as a release coating of pressure-sensitive adhesive tapes, but the bond strength between PPHFP film and a poly (ethylene terephthalate) (PET) substrate film was slightly weak: some part of the PPHFP deposits could be peeled from the PET substrate. Since the XPS results indicated that the bond strength between plasma-polymerized ethylene (PPE) film and PET substrate was strong enough, we tried to deposit PPE and plasma-polymerized ethylene - hexafluoropropene gradient plasma-copolymer between the PET substrate and the PPHFP film. This multi-layer film (MLF) had low enough adhesive strength, 36.6 Nm^–1, for use as the release coating; this value was near that of a control sample, Teflon sheet, 21.6 Nm^–1. Moreover, the bond strength between MLF and PET substrate became stronger than that between PPHFP and PET films.     

Static Yield Stress of an Electro-Rheological Fluid

The static yield stress of an electro-rheological fluid (starch/gas-oil and mesophase-carbon/gas-oil, abbreviated as ERF), congealed by an electric field, has been examined by means of a tensile tester with parallel electrodes. Static yield stress showed different behavior from dynamic yield stress reported by many investigators: thus static yield stress is proportional to applied field strength, but not to the square of it, as is dynamic yield stress. The adhesive force between the particles was not Coulomb's force but Maxwell's force. The theory of McLean and Ikazakiet al.using the Johnsen–Rahbeck effect on the adhesive force of the dust pile on an electrode of the electro-static precipitator was applied and the deduced equation actually explained the phenomena. It was clarified experimentally and theoretically that the physical properties of the ERF particles had no effect on the adhesive force of the pearl chains of a congealed ERF; on the contrary, the volumetric concentration did affect it.     

Influence of Sodium Periodate and Tyrosinase on Binding of Alginate to Adlayers of Mytilus edulis Foot Protein 1

Mytilus edulis foot protein 1 (Mefp-1) is the most well-characterized component of this sea mussel's adhesive plaque. The plaque is a condensed, heterogeneous mixture consisting of a large proportion of cross-linked biopolymers that bonds the mussel to a chosen mooring. Mefp-1 is densely populated with lysine and -3,4-dihyroxyphenylalanine ( -dopa) residues incorporated into a repeating amino acid sequence motif. It has been proposed that one plaque cross-linking reaction is the nucleophilic addition of the ε-amino groups of the lysine residues into the oxidized catechol (o-diphenol) functionality (quinone) of the -dopa residues. In order to determine if this reaction occurs in adlayers of Mefp-1, a previously developed assay for ε-amino groups was applied. Adlayers of Mefp-1 were exposed to an oxidant, either the enzyme, mushroom tyrosinase, or sodium periodate. Binding of alginate to adlayers was used to probe for accessibility of ε-amino groups. It was found that lysine residues lose the ability to bind alginate after exposure to sodium periodate, but that this loss is not clearly due to a reaction with -dopa residues. There is a slight decrease of binding of alginate to adlayers of Mefp-1 exposed to either active or thermally deactivated mushroom tyrosinase, probably due to the obstruction of binding sites by bound enzyme. Adsorption kinetics of mushroom tyrosinase onto adlayers of Mefp-1 for active and thermally inactivated enzyme were nearly identical. Attenuated total reflection Fourier transform infrared spectroscopy was used to characterize these interactions at a germanium (Ge) interface.