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排序方式: 共有418条查询结果,搜索用时 15 毫秒
1.
JA Burger A Ochs K Wirth DP Berger R Mertelsmann R Engelhardt M Roessle K Haag 《Canadian Metallurgical Quarterly》1997,8(2):200-202
BACKGROUND: The increase in portal vascular resistance is a significant complication of metastatic disease to the liver or locally advanced cancer, e.g., biliary cancer. PATIENTS AND METHODS: This paper describes the successful palliative treatment of two cancer patients with portal hypertension presenting with the symptoms of tense ascites, mesenteric congestion, and severe variceal bleeding. By creating a stenttract between a hepatic vein and a main branch of the portal vein and/or by placing an extendable stent into the portal vein, the transjugular intrahepatic portosystemic stent-shunt (TIPS) technique was used to decompress the portovascular system. RESULTS: The TIPS-technique offers a new, safe and effective palliation for malignant portal hypertension. In both patients, the symptoms of the portal hypertension disappeared after the procedure. This was accompanied by a significant improvement of the patients performance status allowing an early ambulation. CONCLUSION: Our findings demonstrate the feasibility and effectiveness of the TIPS procedure as a minimal invasive treatment for portal vein decompression in selected tumor patients. 相似文献
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INTRODUCTION: In a retrospective study a treatment concept for Perthes' disease dependent on the containment was applied. PATIENTS/METHODS: 49 hips of 41 children (9 female, 32 male) were treated between 01. 01. 1990 and 31. 12. 1995. In our concept of treatment a varus femoral osteotomy was performed in 28 cases with not contained hips or less than 4/5 coverage of the femoral head (X-ray/MRI). The other 21 well contained hips with 4/5 coverage or more were treated conservatively with physiotherapy and in case of joint effusion and pain additionally with the use of crutches (partial weight bearing) and anti-inflammatory medication. The average age in the non-operative group at the time of first investigation was 4 years and 9 months (3 y./1 m. to 7 y./1 m.) and 6 years and 3 months (4 y/2 m. to 10 y/0 m.) at our last examination (mean follow up 17.7 months, range of 6 to 72 months). At the time of indication for a varus femoral osteotomy the patients had an average age 6 years and 1 month (3 y./6 m. to 10 y./2 m.), the mean age at the last postoperative examination was 7 years and 11 months (4 y./8 m. to 12 y./5 m.) with an average follow up of 21.5 months (6 to 77 months). RESULTS: For the conservatively treated children we achieved good results (still well contained hips with 4/5 coverage, no decrease of function, no increase of pain) in 85.7% (18 of 21 cases). In 85.7% (24 of 28 cases) we found good results (well contained hips, increase of coverage, no decrease of function, no increase of pain) in the operation group. CONCLUSIONS: The presented concept of therapy in Perthes' disease was practicable for all patients and included the possibility of decision for operative or non-operative treatment. In both groups we achieved good results in 85.7% of the cases. 相似文献
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Stimulus control of ring swimming was studied with male Siamese fighting fish (Betta splendens) using 2-component multiple schedules in which the components were correlated with the presence or absence of air bubbles in the water. In Experiment 1, either response-independent mirror presentations or extinction was juxtaposed with immediate response-dependent mirror presentations. Rates of ring swimming generally were higher with immediate reinforcement than with either response-independent mirror presentations or extinction. In Experiment 2, different durations of response-dependent mirror presentations were juxtaposed. Generally, higher rates of ring swimming occurred with 15-s than with 0-, 1-, or 3-s durations. Results demonstrate that stimulus control of responding can be established with these fish under several conditions of differential reinforcement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Dorn R. Baumgartner A. Goth A. Gutu-Nelle A. Koppenborg J. Rehm W. Schneider R. Schneider S. von Wirth J. Weber D. 《Lightwave Technology, Journal of》1991,9(6):709-714
Mechanically shaped preforms (MSP) have been demonstrated to combine economic non-CVD (chemical vapor deposition) processing and low loss, with a published value of 0.63 dB/km and a size of 30 fkm/preform. Improved processing is proposed which results in a minimum loss of 0.27 dB/km at 1550 nm. Preforms capable of yielding 150 fkm have been produced. Reboiling during preform stretching and fiber pulling is identified as the last remaining problem of the process 相似文献
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Between June 1983 and March 1992, we performed a capsular reconstruction procedure through an anterior approach in ten patients (ten shoulders) who had multidirectional laxity of the shoulder and symptomatic atraumatic posterior glenohumeral instability. The procedure included closure of the capsule in the rotator interval and imbrication of the anterior, inferior, and posteroinferior aspects of the capsule by a double-breasting technique that decreases the overall capsular volume. The mean duration of follow-up was sixty months (range, twenty-four to 103 months). According to the system of Rowe and Zarins, the result was graded as excellent for five shoulders, good for four, and poor for one. On the basis of our results, we recommend capsular reconstruction through an anterior approach only in patients who have persistent multidirectional laxity and symptomatic atraumatic posterior instability of the shoulder despite participation in an intensive rehabilitation program. 相似文献
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A novel mosquitocidal bacterium, Bacillus thuringiensis subsp. jegathesan, and one of its toxins, Cry11B, in a recombinant B. thuringiensis strain were evaluated for cross-resistance with strains of the mosquito Culex quinquefasciatus that are resistant to single and multiple toxins of Bacillus thuringiensis subsp. israelensis. The levels of cross-resistance (resistance ratios [RR]) at concentrations which caused 95% mortality (LC95) between B. thuringiensis subsp. jegathesan and the different B. thuringiensis subsp. israelensis-resistant mosquito strains were low, ranging from 2.3 to 5.1. However, the levels of cross-resistance to Cry11B were much higher and were directly related to the complexity of the B. thuringiensis subsp. israelensis Cry toxin mixtures used to select the resistant mosquito strains. The LC95 RR obtained with the mosquito strains were as follows: 53.1 against Cq4D, which was resistant to Cry11A; 80.7 against Cq4AB, which was resistant to Cry4A plus Cry4B; and 347 against Cq4ABD, which was resistant to Cry4A plus Cry4B plus Cry11A. Combining Cyt1A with Cry11B at a 1:3 ratio had little effect on suppressing Cry11A resistance in Cq4D but resulted in synergism factors of 4.8 and 11.2 against strains Cq4AB and Cq4ABD, respectively; this procedure eliminated cross-resistance in the former mosquito strain and reduced it markedly in the latter strain. The high levels of activity of B. thuringiensis subsp. jegathesan and B. thuringiensis subsp. israelensis, both of which contain a complex mixture of Cry and Cyt proteins, against Cry4- and Cry11-resistant mosquitoes suggest that novel bacterial strains with multiple Cry and Cyt proteins may be useful in managing resistance to bacterial insecticides in mosquito populations. 相似文献
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The mechanical properties of commercially available SiC-based ceramic fibres were measured in the temperature range from 400–1300°C. The measurements were performed in air and in inert gas atmospheres, respectively. The Nicalon and Tyranno fibres were tested as filament bundles and the decrease in strength occurring at temperatures above 600 °C was found in both atmospheres. To obtain a well-defined gauge length at the testing temperature, a furnace with very steep temperature gradients at both ends was built. To eliminate grip-induced damage in the heating zone the fibre bundles were fixed outside the furnace with cold grip units. These grips guaranteed the uniformity of load distribution imposed on to each of the individual filaments in the fibre bundle. A significant shrinkage of the fibres occurring during the creep test performed under low loads indicates a change in the microstructure of the fibres at high temperatures. 相似文献