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31.
Oesophago-respiratory fistula in most instances in a complication of advanced malignant tumours of the oesophagus or the lung. In our patient group eleven oesophago-respiratory and one gastro-respiratory fistulas were encountered. Three patients were operated upon. In one of them with achalasia, early oesophageal carcinoma was discovered in the background of the fistula. Two patients had fistulas without of oesophageal narrowing, therefore, stent implantation into the trachea and bronchus was performed. One of them was previously managed endoscopically with lyodura plug and fibrin glue, but only temporary occlusion of the fistula was obtained. In five patients, seven conventional oesophageal prosthesis (6 Cook, 1 Rüsch) were used to close the fistulas. In one of these patients, three oesophago-respiratory fistulas developed one after the other at the level of the prosthesis funnel. They were closed with three prostheses connected with short silicone tubes. In the last two patients, Gianturco-Z stent was employed. Its advantages over the plastic prostheses include small basic and lager final luminal diameter, lesser predilatation, easier implantation, lower complication and mortality rate. The silicone coated and double funnel stent with expansile force is effective in fistulas closure. On implantation, stent shortening in minimal, allowing precise placement of the stent even in proximal malignant oesophageal stenosis with oesophago-bronchial fistula. The high price of the stent is compensated for by the lower complication rate, shorter hospitalization and subsequent reduction is hospital expenses. Therefore these metal stents should be financed by the National Health Service, at least in specialized centers for managing patients with dysphagia.  相似文献   
32.
Arterial hemodynamics and wall mechanics are important considerations for the vascular clinician for a number of reasons. Hemodynamics and wall mechanics both have been shown to be affecters of disease formation. It is important for the practicing vascular surgeon to know how disease affects both blood flow and wall mechanics and to understand the consequence of hemodynamics on arterial reconstructions. In this article, we summarize the basic concepts of arterial hemodynamics and wall mechanics as they relate to the development of arterial pathology. A few practical mathematical relationships and examples are provided for both illustration and utilization. We also discuss the use of computer models for the estimation of wall stresses in individual abdominal aortic aneurysms.  相似文献   
33.
We have performed a series of experiments to study the effects of a newly developed antisense homology box-derived endothelin (ET) antagonist peptide (ETR-P1/fl) on the early hemodynamic changes in a hyperdynamic endotoxemic dog model. Mean arterial pressure (MAP), cardiac output (CO) and myocardial contractility (MC) were measured in closed-chest animals. Plasma levels of ET-1,2 were determined by radioimmunassay. A hyperdynamic circulatory response was elicited with a 2-hour infusion of 5.3 micrograms/kg of E. coli endotoxin (ETX). Control and ETX-treated animals received an infusion of ETR-P1/fl (0.1 mg/kg) i.v. ETX treatment decreased MAP and MC, increased initially CO, and a long lasting elevation in the plasma ET level was observed. In ETX-treated animals the administration of ETR-P1/fl significantly prolonged the increase in CO and inhibited the depression of MC. Our results suggest that treatment with the ET antagonist ETR-P1/fl may be advantageous in the early phase of endotoxemia.  相似文献   
34.
Regeneration of body parts and their interaction with the immune response is a poorly understood aspect of earthworm biology. Consequently, we aimed to study the mechanisms of innate immunity during regeneration in Eisenia andrei earthworms. In the course of anterior and posterior regeneration, we documented the kinetical aspects of segment restoration by histochemistry. Cell proliferation peaked at two weeks and remitted by four weeks in regenerating earthworms. Apoptotic cells were present throughout the cell renewal period. Distinct immune cell (e.g., coelomocyte) subsets were accumulated in the newly-formed blastema in the close proximity of the apoptotic area. Regenerating earthworms have decreased pattern recognition receptors (PRRs) (e.g., TLR, except for scavenger receptor) and antimicrobial peptides (AMPs) (e.g., lysenin) mRNA patterns compared to intact earthworms. In contrast, at the protein level, mirroring regulation of lysenins became evident. Experimental coelomocyte depletion caused significantly impaired cell divisions and blastema formation during anterior and posterior regeneration. These obtained novel data allow us to gain insight into the intricate interactions of regeneration and invertebrate innate immunity.  相似文献   
35.
The OECD-IAEA Paks Fuel Project was developed to support the understanding of fuel behaviour in accident conditions on the basis of analyses of the Paks-2 incident. Numerical simulation of the most relevant aspects of the event and comparison of the calculation results with the available data from the incident was carried out between 2006 and 2007. A database was compiled to provide input for the code calculations. The activities covered the following three areas: (a) Thermal hydraulic calculations described the cooling conditions possibly established during the incident. (b) Simulation of fuel behaviour described the oxidation and degradation mechanisms of the fuel assemblies. (c) The release of fission products from the failed fuel rods was estimated and compared to available measured data.The applied used codes captured the most important events of the Paks-2 incident and the calculated results improved the understanding of the causes and mechanisms of fuel failure. The numerical analyses showed that the by-pass flow leading to insufficient cooling amounted to 75-90% of the inlet flow rate, the maximum temperature in the tank was between 1200 and 1400 °C, the degree of zirconium oxidation reached 4-12% and the mass of produced hydrogen was between 3 and 13 kg.  相似文献   
36.
This paper investigates the complexity of a general inference problem: given a propositional formula in conjunctive normal form, find all prime implications of the formula. Here, a prime implication means a minimal clause whose validity is implied by the validity of the formula. We show that, under some reasonable assumptions, this problem can be solved in time polynomially bounded in the size of the input and in the number of prime implications. In the case of Horn formulae, the result specializes to yield an algorithm whose complexity grows only linearly with the number of prime implications. The result also applies to a class of formulae generalizing both Horn and quadratic formulae.To the memory of Robert G. Jeroslow  相似文献   
37.
A recently cloned major Schistosoma mansoni egg Ag p38 induced and elicited strong Th1-type responsiveness in mice of H-2k haplotype. Now, we have identified the immunodominant T cell epitope of p38 and analyzed the dynamics of epitope-specific Th responsiveness during murine schistosomiasis mansoni. Overlapping recombinant and synthetic peptides that encompassed the full-length 354 amino acid of p38 were tested for proliferation and cytokine production in peptide- or p38-sensitized mice. The immunodominant T cell epitope of p38 that elicited pulmonary granuloma formation was localized within peptide P4 (amino acids 235-249). The P4-specific cytokine response of splenocytes that had been sensitized s.c. with p38, P4 or soluble egg Ags in IFA, or i.p. with 3000 eggs was predominantly as the Th1 type, with strong IL-2 and IFN-gamma, but trace amounts of IL-4 and IL-5 secretion. At 6.5 wk of infection, splenocytes and mesenteric lymph node cells responded to p38/P4 peptides with predominantly Th1-type responsiveness. This response did not switch to a Th2-type pattern from 8 wk onwards; rather, it underwent down-modulation. Moreover, the hepatic granuloma lymphocytes at 6.5 wk responded to p38/P4 predominantly with Th1-type cytokine production, indicating that they participate in early granuloma formation. From 8 wk onwards an immune deviation to the p38-specific response was observed that was manifested by rising IgG1, IgE, and IgG2a Ab production as opposed to declining Th1- and Th2-type cytokine secretion.  相似文献   
38.
Background: The importance of immune checkpoint molecules is well known in tumor and transplantation immunology; however, much less information is available regarding human pregnancy. Despite the significant amount of information about the TIGIT and CD226 immune checkpoint receptors in immune therapies, very little research has been conducted to study the possible role of these surface molecules and their ligands (CD112 and CD155) during the three trimesters of pregnancy. Methods: From peripheral blood, immune cell subpopulations were studied, and the surface expression of immune checkpoint molecules was analyzed by flow cytometry. Soluble immune checkpoint molecule levels were measured by ELISA. Results: Notable changes were observed regarding the percentage of monocyte subpopulation and the expression of CD226 receptor by CD4+ T and NKT cells. Elevated granzyme B content by the intermediate and non-classical monocytes was assessed as pregnancy proceeded. Furthermore, we revealed an important relationship between the CD226 surface expression by NKT cells and the serum CD226 level in the third trimester of pregnancy. Conclusions: Our results confirm the importance of immune checkpoint molecules in immunoregulation during pregnancy. CD226 seems to be a significant regulator, especially in the case of CD4+ T and NKT cells, contributing to the maternal immune tolerance in the late phase of pregnancy.  相似文献   
39.
The cloud point is an important property of biodiesel, controlling its low temperature behaviour, especially the fluidity of the fuel. Although biodiesel is an interesting renewable energy source, data for the melting/cloud point of biodiesel or simple binary or ternary mixtures of fatty acid ethyl esters (FAEE) are still scarce in the literature, particularly for those involving ethyl esters. The phase diagrams of six binary mixtures of ethyl palmitate with saturated and unsaturated fatty acid ethyl esters were determined by Differential Scanning Calorimetry (DSC). The determined systems were successfully described employing the UNIQUAC model. The experimental data indicates that the cloud point is controlled by the fatty acid ethyl ester in the mixture with higher melting temperature.  相似文献   
40.
Alcalase® (Subtilisin A) was immobilized by simple hydrophobic adsorption onto various surface‐grafted macroporous silica gels resulting in easy‐to‐prepare and stable biocatalysts enabling the efficient kinetic resolution (KR) and dynamic kinetic resolution (DKR) of racemic N‐Boc‐phenylalanine ethyl thioester with benzylamine. The immobilized Alcalase biocatalysts, which retained their activity and selectivity when stored at 4 °C for more than a year, were tested in enzymatic aminolysis in batch and continuous‐flow KRs resulting in (S)‐N‐Boc‐phenylalanine benzylamide in high enantiomeric purity. In KR of the racemic thioester by Alcalase‐catalyzed aminolysis in a continuous‐flow reactor, the productivity (specific reaction rate, rflow) and enantiomeric ratio (E) were studied in the 0–100 °C range. The effect of the temperature on base‐catalyzed racemization of the non‐transformed (R)‐thioester in a continuous‐flow reactor was also investigated in the 0–150 °C range. The continuous‐mode DKR of the racemic thioester in a serial cascade system of six biocatalyst‐filled columns at 50 °C for KR and five grafted silica gel‐filled columns at 150 °C for racemization resulted in the formation of the (S)‐benzylamide in 79% conversion, 8.17 g L −1 h−1 volumetric productivity and 98% ee. This is the first example of a dynamic kinetic resolution of an amino acid derivative in continuous‐flow mode using an alternating cascade of packed‐bed enzyme reactors and racemization reactors kept at different temperatures.

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