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921.
C Ertekin S Yamaner R Güloglu K Günay S Belgerden 《Canadian Metallurgical Quarterly》1997,122(7):535-537
Penetrating injuries of the lower thoracic wall and anterior abdominal wall cause difficulties in the decision for laparotomy. For gunshot wounds laparotomy without further investigations is in most cases justified, but in other penetrating traumata one should use every diagnostic modality to prevent unacceptably high negative laparotomy rates. We performed diagnostic laparoscopy (DL) on 39 patients with penetrating injuries of the anterior abdominal wall and/or lower thoracic wall. Of these 39 patients, 25 had negative and 14 positive results. We had only one false-negative finding. No false-positive result occurred. We think that DL is a very reliable diagnostic tool which requires a relatively high technology. 相似文献
922.
This case report describes an accessory hepatic duct (AHD) identified by intraoperative cholangiography during excisional surgery of a choledochal cyst (CC). The accessory duct was divided and reconstructed successfully to the Roux-en-Y jejunal loop. The postoperative course was uneventful, and follow-up abdominal sonography revealed neither evidence of biliary tract obstruction nor atrophic changes of the liver. It is advocated that an AHD should be meticulously reconstructed if it is divided during excisional surgery of a CC. 相似文献
923.
OBJECTIVE: To investigate if unexpected behaviour of neonatal and paediatric patients connected to syringe pumps could be explained by transient elevation of these devices. DESIGN: Five different commercially available syringe-pumps were set at an infusion rate of 1 ml/h and then subjected to a vertical displacement manoeuvre (height 1 m). The actual delivered infusion volumes in association with the displacement manoeuvre were measured by a high precision weight scale connected to a computer. SETTING: A medical technology laboratory in a university hospital. MEASUREMENTS AND RESULTS: Elevation of the devices resulted in a rapid bolus injection of 0.19-2.28 ml. Returning the devices to their original positions resulted in an aspiration into the system of 0.06-0.34 ml. The times both for bolus injection and for aspiration into the system were less than 1 min in all cases. The updown manoeuvre was followed by a period with zero infusion ranging from 8 to 105 min. CONCLUSIONS: Design flaws in the construction of syringe pumps can expose patients to substantial danger following vertical displacement if potent drugs are being infused. If potent drugs are infused, care should be taken not to change the vertical position of the syringe pump even for short periods of time. Before buying new equipment, the authors recommend that the delivery characteristics of these devices should not only be tested during ordinary bench testing but should also include the reaction to a vertical displacement manoeuvre. 相似文献
924.
A receiver employing frequency discriminator demodulation and maximum likelihood sequence estimator detection is proposed for the GSM mobile telephone system. Computer simulated bit error rates based on two ray and GSM propagation models are presented. The proposed scheme is more tolerant to carrier frequency offset than a coherent system 相似文献
925.
Martonchik J.V. Diner D.J. Pinty B. Verstraete M.M. Myneni R.B. Knyazikhin Y. Gordon H.R. 《Geoscience and Remote Sensing, IEEE Transactions on》1998,36(4):1266-1281
Knowledge of the directional and hemispherical reflectance properties of natural surfaces, such as soils and vegetation canopies, is essential for classification studies and canopy model inversion. The Multi-angle Imaging SpectroRadiometer (MISR), an instrument to be launched in 1998 onboard the EOS-AM1 platform, will make global observations of the Earth's surface at 1.1-km spatial resolution, with the objective of determining the atmospherically corrected reflectance properties of most of the land surface and the tropical ocean. The algorithms to retrieve surface directional reflectances, albedos, and selected biophysical parameters using MISR data are described. Since part of the MISR data analyses includes an aerosol retrieval, it is assumed that the optical properties of the atmosphere (i.e. aerosol characteristics) have been determined well enough to accurately model the radiative transfer process. The core surface retrieval algorithms are tested on simulated MISR data, computed using realistic surface reflectance and aerosol models, and the sensitivity of the retrieved directional and hemispherical reflectances to aerosol type and column amount is illustrated. Included is a summary list of the MISR surface products 相似文献
926.
K Kamigiri T Tokunaga T Sugawara K Nagai M Shibazaki B Setiawan RM Rantiatmodjo M Morioka K Suzuki 《Canadian Metallurgical Quarterly》1997,50(7):556-561
Two new types of macrolide antibiotics, YM-32890 A and B, have been isolated from the fermentation broth of cytophaga sp. YL-02905S. In this paper, the taxonomy of the producing strain, fermentation, isolation, structure elucidation, and biological activity of the antibiotics are reported. YM-32890 A inhibits the growth of staphylococci including a macrolide-resistant strain, but shows no antimicrobial activity against other Gram-positive, Gram-negative bacteria and yeast. 相似文献
927.
Ö. Jonsson T. Larsson M. Rönnqvist 《Structural and Multidisciplinary Optimization》1994,7(1-2):103-111
An efficient and commonly used approach to structural optimization is to solve a sequence of approximate design problems that are constructed iteratively. As is well-known, a major part of the computational burden of this scheme lies in the sensitivity analysis needed to state the approximate problems. We propose a possibility for reducing this burden by streamlining the calculations in a combined approximation and duality scheme for structural optimization. The difference between this scheme and the traditional one is that, instead of calculating all the constraint gradients to state an approximate design problem explicitly, linear combinations of these gradients are generated as they are needed during the solution of the approximate problem by the dual method. We show, by analysing some typical scenarios of problem characteristics, that this rearrangement of the calculations may be a computationally viable alternative to the traditional scheme. An advantage of streamlining the calculations is that there is no need to incorporate an active set strategy in the scheme, as is usually done, since all the design constraints may be taken into consideration without any loss of computational efficiency. This may, clearly, enhance the practical rate of convergence of the overall approximation scheme. Moreover, the proposed rearrangement of the calculations may make it computationally viable to apply iterative equation solvers to the structural analysis problem. Numerical results with direct as well as iterative equation solvers show that the streamlined scheme is a feasible and promising approach to structural optimization. 相似文献
928.
The optimality criteria and numerical algorithms for DCOC are specialized in this part of the two-part paper to multispan structures each span of which is assumed to have a uniform section along its entire length. The steel ratio is allowed to vary freely along the length. Selfweight of the spans is also included in the equilibrium equation of the real system and in the optimality criteria.Section, equation, figure and table numbers continue from Part I. 相似文献
929.
AR Thomassen E Kj?ller B Sigurd I G?thgen G Johannsen T Pedersen JE Nielsen-Kudsk PE Thomsen 《Canadian Metallurgical Quarterly》1994,156(1):31-38
We report herein the phenotypic and functional analysis of human bone marrow and thymus derived early T cells. Commitment to T cell lineage is acquired during CD7 antigen expression by CD34+ precursors in human bone marrow and before thymus colonization. Early thymocytes show similar phenotypic characteristics as bone marrow T cells. They rapidly acquire CD4 before the dual expression of CD4 and CD8. Their expansion and differentiation is regulated by two major factors: thymic stroma and cytokines produced by these stroma cells or by thymocytes themselves. Among cytokines, IL1 and sCD23 produced by thymic epithelial cells support in vitro early T cell development. 相似文献
930.
KK Lyngberg M Harreby H Bentzen B Frost B Danneskiold-Sams?e 《Canadian Metallurgical Quarterly》1994,75(11):1189-1195
The effects of physical training on elderly, fragile patients with rheumatoid arthritis (RA) who are on low-dose steroids were investigated. The controlled study included 24 patients who had been treated with low-dose steroids for 2 years. Each patient was assigned either to a treatment group receiving training or to an untrained control group. The training took place over a 3-month period and was based on a protocol using progressive interval training consisting of bicycle exercises, heel lifts, and step-climbing. The exercises were performed twice weekly for 45 minutes. Comparison of the two groups showed that disease activity did not increase in the trained group and that fewer, but not significantly fewer, swollen joints were observed in this group (p = 0.06). No significant changes were noticed in erythrocyte sedimentation rate, tender joints, or morning stiffness. The work capacity of the trained patients were doubled and the numbers of repetitions increased 76%. Individually adapted exercise programs can therefore be recommended for elderly rheumatoid arthritis patients on steroid treatment. 相似文献