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排序方式: 共有214条查询结果,搜索用时 15 毫秒
61.
AM Ramzy M Sattar Y Amin RT Mansour GI Serour MA Aboulghar 《Canadian Metallurgical Quarterly》1998,13(1):198-202
BACKGROUND: Open lung biopsy (OLB) has long been considered the gold standard for the diagnosis of parenchymal lung disease. With recent advances in computed tomographic imaging and diagnostic techniques (eg, bronchoscopy), we thought it necessary to reevaluate the role of OLB in the management of patients with interstitial lung disease. METHODS: We carried out a retrospective analysis of 103 OLBs performed at Hadassah University Hospital, Jerusalem, and Carmel Medical Center, Haifa, between 1980 and 1994. Data gathered included demographic information, underlying condition, indications for biopsy, diagnosis before biopsy, final diagnosis, change in therapy, and mortality. "Benefit" was defined as a change in therapy resulting in survival. RESULTS: There were 45 immunocompetent patients (group 1), 39 immunocompromised patients (group 2), and 26 children (group 3), 7 of whom were included in group 2 for analysis. Overall, a diagnosis was reached after OLB in 85% of patients. An unexpected diagnosis was reached in 52%, and a change in therapy was instituted in 46%. The overall mortality rate was 20%. In group 1, the mortality rate was 13%, and "benefit" from OLB was reached in only 18%. In group 2, the mortality rate was 39%, and "benefit" was achieved in 46%, and in group 3, the mortality rate was 12% and "benefit", 50%. CONCLUSIONS: Open lung biopsy is an excellent diagnostic technique. In immunocompetent patients, the "benefit" is relatively low, as therapy (corticosteroids) is frequently used after biopsy. In immunocompromised patients, therapy changes substantially after OLB, but mortality is high. Therefore, OLB should be reserved for patients in whom the diagnosis is likely to lead to a change in therapy and in patients in whom the underlying condition has a reasonable prognosis according to the clinical impression by the attending physician. 相似文献
62.
63.
Sattar Saira Imran Muhammad Mushtaq Zarina Ahmad Muhammad Haseeb Arshad Muhammad Sajid Holmes Melvin Maycock Joanne Nisar Muhammad Faisal Khan Muhammad Kamran 《Food science and biotechnology》2020,29(10):1381-1388
Food Science and Biotechnology - The peach functional beverages pasteurized for 10 min at 90 °C, microwaved for 1.5 min at 850 W of power and sonicated for... 相似文献
64.
N. Bibi M. A. Chaudry F. Khan Z. Ali A. Sattar 《Molecular nutrition & food research》2001,45(2):82-86
Garden picked mature but unripe fresh persimmon fruits were unipackaged in different thicknesses of polyethylene (PE) and stored at room (18.5–30°C) and refrigerated temperature (6 ± 1°C). Maximum mean methanol extractable sinapine (0.168%( catechin (1.51%( and leucoanthocyanidine (10.94 ΔA550/g) were recorded in the unipackaged samples kept at room temperature during 6 weeks storage, whereas the minimum values for water extractable phenolics (sinapin, catechin and procyanidin) were recorded in unipackaged samples under refrigerated temperature. The mean maximum weight loss of 12.58 and 7.90% was recorded in control samples kept at room temperature and low temperature, respectively. The weight loss for unipackaged in different thicknesses of PE ranged between 0.93–0.96% and 0.43–0.45% for samples kept at room and low temperature, respectively. Changes in texture values were significantly faster in control than unipackaged samples (P < 0.05). Low temperature combined with unipackaging in PE film performed better for the maintenance of overall fruit quality during post‐harvest storage. 相似文献
65.
Siavash Sattar Rahul Jujjavarapu Sergei G. Kravchenko Oleksandr G. Kravchenko 《Journal of the American Ceramic Society》2020,103(11):6543-6553
In this study, a novel computational micromechanical framework is proposed to predict the effective mechanical properties of the ice-templated ceramics under off-axis compressive loading. The mechanical behavior is simulated by a computational micromechanical model and validated against experimental results. Smeared cracking approach was used to describe failure in ice-templated alumina. The representative volume element (RVE) was developed based on the honeycomb analogy of lamellar walls considering the morphology of the material. The periodic boundary conditions were applied in RVE to simulate bulk behavior of the material. The compression testing was conducted on the ice-templated alumina samples to obtain the effective compressive moduli and strength with different loading angles. Digital image correlation method was used to measure strain field during the experiment and quantify the effective misalignment angle corresponding to porous material. The effective stiffness and strength obtained from RVE analysis compared well with experimental results. The proposed micro-mechanical RVE model allows for determining the properties of the ice-templated porous ceramic for various off-axis angles. 相似文献
66.
Chaudhry Haider Ali Abdul Hannan Asif Tanveer Iqbal Abdul Sattar Qureshi Mohsin Ali Kazmi Saima Yasin 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(9):1076-1083
In this study, potassium hydroxide-treated animal bones were employed? as a solid heterogeneous catalyst in transesterification of waste cooking oil. This catalyst was characterized by the Fourier-transform infrared spectroscopy (FTIR), and it displayed high-catalytic activity for biodiesel production. Optimum conditions for biodiesel production were catalyst loading 6.0% (w/w) of oil, methanol/oil molar ratio 9:1, calcination temperature 800°C, reaction temperature 65°C, and reaction time of 5 h, which gave maximum biodiesel yield of 84%. Reusability of the catalyst was also confirmed by repeated use of the same catalyst three times without losing much of its activity. Hence, calcined goat bones were found to be a potentially applicable catalyst for biodiesel production at industrial scale. 相似文献
67.
M. A. Sattar 《Holz als Roh- und Werkstoff》1993,51(6):409-416
Available literature of the technology of solar timber drying during the last three decases is reveiwed. Various designs ranging from the simple tents to the automated solar kilns are reported. In almost all the cases, the performances of the driers are satisfactory in respect of the final moisture content, drying time and quality of timber. The solar drying is found technically viable, and except for the sophisticated solar kilns it is also economically feasible. 相似文献
68.
Bela Stantic Abdul Sattar Paolo Terenziani 《Journal of Intelligent Information Systems》2009,32(3):297-323
Most modern database applications involve a significant amount of time dependent data and a significant portion of this data
is now-relative. Now-relative data are a natural and meaningful part of every temporal database as well as being the focus of most queries. Previous studies
indicate that the choice of the representation of now significantly influences the efficiency of accessing bitemporal data. In this paper we propose and experimentally evaluate
a novel approach to represent now that we termed the POINT approach, in which now-relative facts are represented as points on the transaction-time and/or valid-time line. Furthermore, in the POINT approach we propose a logical query transformation that relies on the above representation and on the geometry features of
spatial access methods. Such a logical query transformation enables off-the-shelf spatial indexes to be used. We empirically
prove that the POINT approach is efficient on now-relative bitemporal data, outperforming the maximum timestamp approach that has been proven to the best approach to now-relative data
in the literature, independently of the indexing methodology (B
+ - tree vs R
*- tree) being used. Specifically, if spatial indexing is used, the POINT approach outperforms the maximum timestamp approach to the extent of factor more than 10, both in number of disk accesses
and CPU usage. 相似文献
69.
Ahmed M. Abdel Sattar John R. Dickerson M. Hanif Chaudhry 《Canadian Metallurgical Quarterly》2009,135(4):283-295
In this paper, a wavelet-Galerkin method is utilized to solve the hyperbolic partial differential equations describing transient flow in a simple pipeline. Two wavelets (Haar and Daubechies) are utilized as bases for the Galerkin scheme. The governing equations are solved for the expansion coefficients, which are then used to reconstruct the signal at the downstream end of the pipeline; the computed results are in an excellent agreement with those calculated by using the method of characteristics including laminar or linearized turbulent friction terms. Most importantly, the wavelet-Galerkin approach allows the transient flow equations to be solved directly for the expansion coefficients at a certain level of resolution. This can be used to form the wavelet multiresolution framework that can be utilized for further analysis, such as feature extraction and signal identification. 相似文献
70.
An Adaptive Hybrid ARQ Scheme 总被引:1,自引:0,他引:1
A hybrid ARQ in which the transmitter adaptively selects an FEC code according to the channel condition is presented and analyzed. The code is selected according to the past transmissions and acknowledgements by an algorithm which is a generalization of that in [1]. The throughput is obtained as a function of the frame error rate for a general system employing the adaptive hybrid ARQ with acknowledgements that arrive instantly on an error-free return channel. The throughput is obtained as a function of the signal-to-noise ratio for an example quad rate system employing convolutional codes with non-coherent frequency shift keying over the uncorrelated Rayleigh fading channel. This allows the best choice for the parameters of the algorithm to be made. In the case that the channel bit errors are independent, the generalization offers performance improvement of less than 10% over that in [1]. But when the channel errors are bursty, as in the case of Rayleigh fading with finite bit interleaving, the generalization offers throughput improvement as high as 24%. We go on to consider incorporating code combining with the adaptive scheme to form an adaptive memory hybrid ARQ. Simulation of a system using complementary punctured convolutional codes with 4 code rates shows that 2-level code combining can extend the adaptive scheme's useful throughput into the low SNR region by approximately 4 dB. 相似文献