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排序方式: 共有600条查询结果,搜索用时 15 毫秒
61.
K Junker W Werner C Mueller W Ebert J Schubert U Claussen 《Canadian Metallurgical Quarterly》1999,14(2):309-313
In order to determine the value of fluorescence in situ hybridization (FISH) in the diagnosis and follow-up of bladder cancer interphase cytogenetics was performed on cells from urine and bladder washings. 50 ml of urine or bladder washings were collected. FISH was carried out using centromere probes for chromosomes 7, 8, 9 and 12 according to standard protocols. In each case 100 cell nuclei were analysed. Fifty-four samples from urine and 67 samples from bladder washing were analysed by FISH in comparison with results obtained by conventional cytology. Sensitivity of detection of tumor cells by FISH was 68.5% in urine and 63% in bladder washings regardless of tumor stage and grade. Sensitivity obtained by conventional cytology was 50% in urine and 77.3% in bladder washings. FISH on cells from urine samples is an effective complement to the standard urine cytology. Using centromere probes this approach is characterized by high specificity and sensitivity in tumors with T-category higher than pTa and grade higher than G1. 相似文献
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63.
L Schuchardt H Steinmetz J Ehret A Ebert T G Schmitt 《Water science and technology》2004,50(11):199-206
In order to support the operation of wastewater systems and the workflow of sewage systems an application for demonstration has been developed to show exemplarily how a mobile information system can be transferred into practice and used by the staff. The paper presents a scalable information visualisation system, which can be used with mobile devices. The regarded information data does not only include process data, but also general information about buildings and units, work directions, occupational safety regulations as well as instructions of first aid in case of a work accident. This is particularly appropriate for the use in remote facilities. The implementation is based on but not limited to SQL, JSP and HTML. 相似文献
64.
Bernstein A Shouakar-Stash O Ebert K Laskov C Hunkeler D Jeannottat S Sakaguchi-Söder K Laaks J Jochmann MA Cretnik S Jager J Haderlein SB Schmidt TC Aravena R Elsner M 《Analytical chemistry》2011,83(20):7624-7634
Chlorine isotope analysis of chlorinated hydrocarbons like trichloroethylene (TCE) is of emerging demand because these species are important environmental pollutants. Continuous flow analysis of noncombusted TCE molecules, either by gas chromatography/isotope ratio mass spectrometry (GC/IRMS) or by GC/quadrupole mass spectrometry (GC/qMS), was recently brought forward as innovative analytical solution. Despite early implementations, a benchmark for routine applications has been missing. This study systematically compared the performance of GC/qMS versus GC/IRMS in six laboratories involving eight different instruments (GC/IRMS, Isoprime and Thermo MAT-253; GC/qMS, Agilent 5973N, two Agilent 5975C, two Thermo DSQII, and one Thermo DSQI). Calibrations of (37)Cl/(35)Cl instrument data against the international SMOC scale (Standard Mean Ocean Chloride) deviated between instruments and over time. Therefore, at least two calibration standards are required to obtain true differences between samples. Amount dependency of δ(37)Cl was pronounced for some instruments, but could be eliminated by corrections, or by adjusting amplitudes of standards and samples. Precision decreased in the order GC/IRMS (1σ ≈ 0.1‰), to GC/qMS (1σ ≈ 0.2-0.5‰ for Agilent GC/qMS and 1σ ≈ 0.2-0.9‰ for Thermo GC/qMS). Nonetheless, δ(37)Cl values between laboratories showed good agreement when the same external standards were used. These results lend confidence to the methods and may serve as a benchmark for future applications. 相似文献
65.
Maik Scheller 《Journal of Infrared, Millimeter and Terahertz Waves》2014,35(8):638-648
The potential of terahertz (THz) time domain spectroscopy to simultaneously determine the complex dielectric parameters of materials and their geometrical thickness is of high interest for scientific spectroscopy and for general metrology. This paper provides an overview of the background of the data extraction from THz measurements and discusses the accuracy and ambiguity of this extraction process. It is shown that the signal to noise ratio of the measurement as well as the bandwidth of the accessible THz spectrum define the limitation of the achievable accuracy in the data extraction. 相似文献
66.
Monika Ku
nia Beata Zygmunt-Kowalska Artur Szajding Anna Magiera Rafa Stanik Maik Gude 《International journal of molecular sciences》2022,23(17)
The aim of the article is to compare two types of fly ash (from the fluidized and pulverized coal combustion process) as a filler for rigid polyurethane foam. Pulverized fly ash (PFA) is widely used in building materials, while fluidized fly ash (FFA) is not currently recycled, but landfilled. The produced rigid polyurethane foams were reinforced with 5 and 10% by weight addition of fly ash from two different types of boilers. The foaming process, physical properties, morphologies and thermal degradation were subject to comparative analysis. The research indicated that fly ash intensifies the reactions of foam synthesis, most commonly, polyurethane (PU) foam with an addition of 10% PFA. What is interesting is that both ashes can be used in PU foam technology as they do not cause deterioration of the physical parameters. As shown, the addition of filler affects the morphology and impairs the brittleness. Additionally, the use of fly ash from coal combustion in the technology of polyurethane materials complies with the guidelines of the circular economy stated in the European Union legislation. Partial replacement of petrochemical components with waste filler also reduces the total energy consumption in the production of PU composites. 相似文献
67.
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69.
TJ Ebert BJ Robinson TD Uhrich A Mackenthun PJ Pichotta 《Canadian Metallurgical Quarterly》1998,89(6):1524-1531
BACKGROUND: Sevoflurane has a lower blood:gas partition coefficient than isoflurane, which may cause a more rapid recovery from anesthesia; it also might cause faster emergence times than for propofol-based anesthesia. We evaluated a database that included recovery endpoints from controlled, randomized, prospective studies sponsored by Abbott Laboratories that compared sevoflurane to isoflurane or propofol when extubation was planned immediately after completion of elective surgery in adult patients. METHODS: Sevoflurane was compared to isoflurane in eight studies (N=2,008) and to propofol in three studies (N=436). Analysis of variance was applied using least squares method mean values to calculate the pooled mean difference in recovery endpoints between primary anesthetics. The effects of patient age and case duration also were determined. RESULTS: Sevoflurane resulted in statistically significant shorter times to emergence (-3.3 min), response to command (-3.1 min), orientation (-4.0 min) and first analgesic (-8.9 min) but not time to eligibility for discharge (-1.7 min) compared to isoflurane (mean difference). Times to recovery endpoints increased with increasing case duration with isoflurane but not with sevoflurane (patients receiving isoflurane took 4-5 min more to emerge and respond to commands and 8.6 min more to achieve orientation during cases longer than 3 hr in duration than those receiving sevoflurane). Patients older than 65 yr had longer times to orientation, but within any age group, orientation was always faster after sevoflurane. There were no differences in recovery times between sevoflurane and propofol. CONCLUSIONS: Recovery from sevoflurane was 3-4 min faster than with isoflurane in all age groups, and the difference was magnified in longer-duration surgical cases (> 3 hr). 相似文献
70.