Rubber band ligation of hemorrhoids: relapse as a function of time

Rubber band ligation is a well established treatment of internal second-degree hemorrhoids. Up to now, the long-term results (> 5 years) of this method have not been assessed. The aim of this study was to determine the long-term success rate of rubber band ligation in patients with a first episode of second-degree hemorrhoids not responding to medical treatment (local cream with laxative). A total of 92 patients who were treated between 1979 and 1997 for second-degree hemorrhoids responded to a questionnaire. The need for complementary conservative (sclerotherapy, cryotherapy or rubber band ligation) or surgical treatment was considered indicative of relapse. The collected data were analyzed according to the Kaplan-Meier method. The average follow-up time was 5.6 years. There were 21 patients who suffered a relapse. The probability of successful treatment was 0.77 (range: 0.67-0.88) after 5 years and 0.68 (range: 0.5-0.86) after 10.6 years. We conclude that rubber band ligation represent an efficient long-term treatment for second-degree hemorrhoids. Approximately two thirds of the patients are cured after 5 years and more than a half after 10 years.     

Electron microscopy study of mesophase pitch-based graphite fibres

A comprehensive electron microscopic investigation of the structure of the graphitic sheet in mesophase pitch-based fibres is presented.In situ brightfield and (00l) darkfield observation of the sheets in sub micrometre fibres reveals a finely striated structure, associated with three-dimensional order. (hkl) darkfield imaging of the sheets in their edge-on and face-on orientations indicates that the striations correspond to the edge view of a mosaic of graphite grains. The grains have lateral dimensions of 100 to 200 nm on average but are only a few atomic layers thick.In situ lattice imaging of the fibre edges indicates a very high level of lattice perfection of the (00l) domains below the fibre surface, quite in line with the outstanding mechanical and thermal properties of this type of fibres. A variety of surface defects are revealed. Preferential orientation effects of the sheet texture on the fibre electron diffraction pattern are described.     

Digital Switching in France

This paper intends firstly to present how digital switching was introduced into the French network nearly ten years ago and what are the main advantages brought by digital switching systems. Various cases in the network such as trunk or local exchanges are examined; general as well as particular advantages are shown. Secondly, the technical requirements for these exchanges are described; an emphasis is put on the specific aspects of digital switching. Digital switching systems already in operation or on the verge of being commissioned are outlined. Finally, different tables give information concerning mainly the number of subscriber lines connected to class 3 and 4 digital exchanges by the end of 1978.     

Problems in the application of structural equation modeling: Comment on Randhawa, Beamer, and Lundberg (1993).

Critique methodological aspects of B. S. Randhawa's et al (see record 1993-23567-001) structural equation modeling (SEM) of relations between self-efficacy, attitudes, and achievement in mathematics. Major findings of their study were that self-efficacy mediated the effects of attitudes on achievement and that self-efficacy and attitudes were more strongly related to achievement for boys than for girls. The authors' reanalysis of their data does not substantiate these conclusions. Rather, it identifies inappropriate applications of SEM and the consequent misinterpretations of results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Influence of C60 Powders On Cultured Human Leukocytes

In order to check its possible acute toxicity, C₆₀ was incorporated into living human phagocytes. It was observed that C₆₀ has no influence on the survival of human leukocytes.     

Regulation of NMDA receptor phosphorylation by alternative splicing of the C-terminal domain

The NMDA (N-methyl D-aspartate) receptors in the brain play a critical role in synaptic plasticity, synaptogenesis and excitotoxicity. Molecular cloning has demonstrated that NMDA receptors consist of several homologous subunits (NMDAR1, 2A-2D). A variety of studies have suggested that protein phosphorylation of NMDA receptors may regulate their function and play a role in many forms of synaptic plasticity such as long-term potentiation. We have examined the phosphorylation of the NMDA receptor subunit NMDAR1 (NR1) by protein kinase C (PKC) in cells transiently expressing recombinant NR1 and in primary cultures of cortical neurons. PKC phosphorylation occurs on several distinct sites on the NR1 subunit. Most of these sites are contained within a single alternatively spliced exon in the C-terminal domain, which has previously been proposed to be on the extracellular side of the membrane. These results demonstrate that alternative splicing of the NR1 messenger RNA regulates its phosphorylation by PKC, and that mRNA splicing is a novel mechanism for regulating the sensitivity of glutamate receptors to protein phosphorylation. These results also provide evidence that the C-terminal domain of the NR1 protein is located intracellularly, suggesting that the proposed transmembrane topology model for glutamate receptors may be incorrect.     

A study of the thermal degradation of polystyrene by thermal volatilization analysis

A TVA study of several anionic polystyrene samples, having number average molecular weights in the range of 4.6 × 10³ to 2 × 10⁶, reveals a hitherto unobserved molecular weight dependence of the overall apparent Arrhenius preexponential factor as determined by the method of Roche.² The latter effect is discussed in terms of a model in which the zip length and chainscission rate constants are both functions of molecular weight. It is suggested that the functional dependence of the kinetic parameters on molecular weight is a reflection of their hydrodynamic coupling to the viscosity of the molten polymer.