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961.
Both regional analgesia and systemic opioid therapy (e.g. PCA) are commonly used for pain relief following thoracic surgery. Many anaesthesiologists are reluctant to use thoracic epidural analgesia on general surgical wards. Therefore, we investigated in a prospective randomised study the efficacy of intercostal blocks (ICB) or interpleural analgesia (IPA) compared to PCA with systemic opioids (PCA). Following ethics committee approval and informed consent, 45 thoracotomy patients were randomised for postoperative pain management: group 1: intravenous PCA with piritramide (PCA-control), group 2: intercostal blocks of the segments concerned with 5 ml bupivacaine 0.5% at the end of surgery and 6 hours thereafter (ICB), group 3: interpleural analgesia with 20 ml bupivacaine 0.25% applied every 4 hours using a catheter placed during surgery near the apex of the pleural space (IPA). Patients in the ICB and IPA groups were able to obtain additional pain relief by PCA with piritramide. Alternative medication for all groups in case of insufficient analgesia was metamizol. Both regional analgesia groups used significantly less piritramide up to the 3rd (IPA) or 7th (ICB) postoperative day than the control group (p < 0.05). The consumption of metamizol was lower as well (n. s.). No significant differences between the study groups were observed with regard to pain scores (visual analogue scale VAS) at rest, during deep inspiration, coughing or mobilisation. Respiratory parameters as forced vital capacity, forced expiratory volume (1 sec) and peak flow (FVC; FEV1; PF) were reduced significantly following thoracotomy and showed a slow restitution in all three study groups without major inter-group differences. Intercostal blocks and interpleural analgesia significantly reduce opioid demand following thoracotomy and are effective means of postoperative pain management. Nevertheless, in contrast to epidural analgesia, both methods have to be supplemented by, or combined with, systemic analgesics in most patients. On the other hand, compared to epidural analgesia, ICB and IPA are less invasive and easier to manage on general surgical wards.  相似文献   
962.
963.
Zusammenfassung Es ist l?ngst eine Selbstverst?ndlichkeit: Durch die Globalisierung und dynamische M?rkte stehen Unternehmen st?ndig vor der Herausforderung, zentrale Gesch?ftsabl?ufe den Marktver?nderungen anzupassen und sich darüber hinaus durch Innovationen Wettbewerbsvorteile zu schaffen. Kosten und Nutzen müssen dabei in einem sinnvollen Verh?ltnis stehen.  相似文献   
964.
In the past few years, there have been significant advances made in the design and engineering of “intelligent” workplaces, buildings that not only accommodate major advances in office technology but provide better physical and environmental settings for the occupants. This paper will briefly present recent approaches to the creation of innovative environments for the advanced workplace. The architectural and engineering advances demonstrated in Japan, Germany, North America, the United Kingdom, and France can be summarized in four major system categories: (1) enclosure innovations including approaches to load balancing, natural ventilation and daylighting; (2) heating, ventilation and air-conditioning (HVAC) system innovations including approaches to local control and improved environmental contact; (3) data/voice/power “connectivity” innovations; and (4) interior system innovations, including approaches to workstation and workgroup design for improved spatial, thermal, acoustic, visual and air quality.

In-depth international field studies of over 20 intelligent office buildings have been carried out by a multidisciplinary expert team of the Advanced Building Systems Integration Consortium (ABSIC) based at Carnegie Mellon University. ABSIC is a university-industry-government partnership focused on the definition and development of the advanced workplace. The ABSIC field team evaluated the component and integrated system innovations for their multidimensional performance qualities, through expert analysis, occupancy assessments and field diagnostics.

Based on the results of the case studies and building on the most recent technological advances, the ABSIC team developed the concepts for the Intelligent Workplace, a 7000 square foot living laboratory of office environments and innovations. This project is now under construction at Carnegie Mellon University and its features are discussed in the second section of this paper.  相似文献   

965.
The by far leading technology for manufacturing MEMS devices is Si-micromachining with its various derivatives. However, many applications of microsystems have requirements on materials basis, geometry, aspect ratio, dimensions, shape, accuracy of microstructures, and number of parts that cannot be fulfilled easily by mainstream silicon-based micromachining technologies. LIGA, an alternative microfabrication process combining deep X-ray lithography, plating-through-mask and molding, enables the highly precise manufacture of high-aspect-ratio microstructures with large structural height ranging from hundreds to thousands of micrometers thick. These tall microstructures can be produced in a variety of materials with well-defined geometry and dimensions, very straight and smooth sidewalls, and tight tolerances. LIGA technology is also well suited for mass fabrication of parts, particularly in polymer.Many microsystems benefit from unique characteristics and advantages of the LIGA process in terms of product performance. The LIGA technology is briefly reviewed. The strengths of the manufacturing method and its main fields of application are emphasized with examples taken from various groups worldwide, especially in micromechanics and microoptics.  相似文献   
966.
Starting from 2,4,6-triiodophenol, 2,3,5-triiodobenzoic acid and 3,5-bis(acetylamino)-2,4,6-triiodobenzoic acid, polymerizable methacrylates were synthesized and characterized by elemental analyses, IR, 1H-NMR and 13C-NMR spectroscopy. The iodine-containing methacrylates show a different radical polymerization behaviour. 2,4,6-Triiodophenyl methacrylate gives only oligomeric products in the presence of azoisobutyronitrile (AIBN), whereas 2-methacryloyloxyethyl 2,3,5-triiodobenzoate yields polymers. On the basis of mixtures of isomeric 1,3-dimethacryloyloxy-2- and 1,2-dimethacryloyloxy-3-(2,3,5-triiodobenzoyloxy)propane with usual crosslinking monomers, radiopaque materials were prepared.  相似文献   
967.
The reactivity and adsorption properties of cellulose fibres are critical for successful treatment because behavior during the finishing process is determined by both structure and surface properties. The fine structure of natural cellulose fibres i.e. cotton, is different from the regular viscose, modal and new types of regenerated cellulose fibres i.e. lyocell, which are clarified by different hydrophilic/hydrophobic character of fibres and different adsorption properties. Tensiometry, seldom used in fibre characterization was used to obtain the differences in the adsorption properties of different cellulose fibres. The surface tension, contact angle and adsorption were measured, and then compared with various methods for determining water adsorption. Currently some additional methods especially sensitive to surface properties (electrokinetic properties of fibres) are being applied in order to characterize the adsorption character and reactivity of the fibre surfaces. The streaming potential was measured due to the fact that the interaction properties are strongly influenced by electric charges on the surface, and from these values the zeta potential (ζ) was calculated as a function of the pH and the surfactant concentration in the liquid phase. As with the results of fibre reactivity and adsorption properties obtained by conventional methods, the electrokinetic character of the materials and their adsorption ability determined using the tensiometry also show the same phenomena. The natural fibres have the smaller hydrophilic character and they are less reactive than the regenerated ones, so the ζmax of cotton is the highest and the contact angle ϕ the greatest [1, 2, 3] Electronic Publication  相似文献   
968.
Wholesale ribs (n = 40) were dissected to determine composition from anterior to posterior end. There were much greater differences in tissue amounts from different anatomical locations within the wholesale rib than between wholesale ribs from carcasses of different USDA yield grades. Kernel fat (seam fat between the longissimus and spinalis dorsi muscles) was found in considerably higher amounts in the 7th, 8th, and 9th rib bone sections. Removal of the lip from IMPS 112A decreased the separable fat content of ribeyes by approximately 46%. This large decrease in fat could make the ribeye more appealing to today's consumer.  相似文献   
969.
The purpose of satellite-to-satellite tracking (SST) and/or satellite gravity gradiometry (SGG) is to determine the gravitational field on and outside the Earth's surface from given gradients of the gravitational potential and/or the gravitational field at satellite altitude. In this paper both satellite techniques are analysed and characterized from a mathematical point of view. Uniqueness results are formulated. The justification is given for approximating the external gravitational field by finite linear combination of certain gradient fields (for example, gradient fields of single-poles or multi-poles) consistent to a given set of SGG and/or SST data. A strategy of modelling the gravitational field from satellite data within a multiscale concept is described; illustrations based on the EGM96 model are given.  相似文献   
970.
Due to their ability to form self-assembled structures, block copolymers offer various possibilities for material separation. Flat and hollow filament membranes with regularly arranged pores of the same diameter and high pore number density can be produced from self-assembling block copolymers. The pore sizes and functionalities of these membranes and thus their application possibilities in the material separation can be adjusted in different ways, whereby the setting of these parameters on finished membrane structures is particularly interesting. Furthermore, tailor-made amphiphilic block copolymers can be used for the specific extraction of substances from aqueous (hydrophilic) solutions to organic (hydrophobic) solutions.  相似文献   
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