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1.
The authors report on their experience about urinary cytology in 1991. They studied 100 patients with cytology and histology, carried by cystoscopy and cold-mapping biopsy, trying to have notice about cytological value and proficiency. 相似文献
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The objective of this study was to investigate how color stability of beef is affected by vacuum skin packaging (VSP) compared with vacuum packaging (VP) and high-oxygen modified atmosphere packaging (MAP; 80% O(2) and 20% CO(2)). Longissimus lumborum muscles were aged in vacuum for 7days and then cut into 2-cm-thick slices and repacked using VSP, VP and MAP for another 7days. Color stability was measured during the next 5days in air and samples for α-tocopherol and NADH analyses were obtained at the beginning and end of aerobic storage. Color stability, α-tocopherol and NADH of steaks were affected by packaging methods and storage time in air (P<0.05). Higher a* value was obtained in VSP on day 5 compared with VP. Steaks packed in VSP had better color stability than in VP and their color was similar to MAP at the end (day 5) of storage. 相似文献
4.
In this paper, we analyze the problem of throughput-efficient distributed coalition formation (CF) of selfish/altruistic nodes in ad hoc radio networks. We formulate the problem as a hedonic CF game with non-transferable utility and propose different preference relations (CF rules) based on individual/group rate improvement of distributed nodes. We develop a hedonic CF algorithm, through which distributed nodes may self-organize into stable throughput-efficient disjoint coalitions. We apply the concept of frequency reuse over different coalitions, such that the members of each coalition will transmit over orthogonal sub-bands with the available spectrum being optimally allocated among them. We study the computational complexity and convergence properties of the proposed hedonic CF algorithm under selfish and altruistic preferences, and present means to guarantee Nash-stability. In addition, we identify the scenarios in which a CF process might lead to instability (CF cycle), and we propose methods to avoid cycles and define different exit procedures if a CF cycle is inevitable. Performance analysis shows that the proposed algorithm with optimal bandwidth allocation provides a substantial gain, in terms of average payoff per link, over existing coalition formation algorithms for a wide SNR range. 相似文献
5.
Mokhtar Benhanifia Wessam M. Mohamed Yuva Bellik Hama Benbarek 《International Journal of Food Science & Technology》2013,48(12):2521-2527
The aim of this study was the investigation of antimicrobial and antioxidant activities of different ethanolic extracts of propolis (EEP) collected from north‐western Algeria. Total polyphenols and flavonoids contents of extracts were measured. The UV absorption spectrum showed and confirmed their polyphenols constituents. All EEPs exerted antibacterial activity against Gram‐positive bacteria, but no effect on Gram‐negative bacteria. The minimum inhibitory concentration (MIC) of EEPs ranged from 0.01% to 2.6% v/v. The antioxidant activity was measured using ferric‐reducing power (FRAP), 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) free radical‐scavenging and ESR methods. Propolis TIA‐2 and MOH‐MAS samples showed the highest antioxidative capacity, after 35 min, while TIA‐1, NED‐TL and SFS‐SBA samples showed the highest antioxidative potential of measured EEPs, after 3 min. TIA‐2 sample showed the highest antibacterial, antioxidant activity and highest DPPH free radical‐scavenging activity as well as the highest polyphenols and flavonoids content, compared with other propolis samples. 相似文献
6.
Acknowledgment Procedures at Radio Link Control Level in GPRS 总被引:1,自引:0,他引:1
7.
Wessam S. Inas A. Ahmed M. 《AEUE-International Journal of Electronics and Communications》2005,59(7):384-391
In this paper, a new CMOS CCII+ is proposed. The circuit is characterized by high precision in voltage tracking and exhibits very low input resistance. An adaptive voltage offset cancellation methodology is introduced and then applied to the proposed circuit. As a result, a higher accuracy CCII+ is presented. For both circuits, the voltage offset cancellation is independent of the input current and voltage. To demonstrate the strength of the proposed architectures, fair comparisons with Liu and Yodprasit CCII realizations are held. 相似文献
8.
Layali Rashid Wessam M. Hassanein Moustafa A. Hammad 《The Journal of supercomputing》2010,53(2):293-312
The sort operation is a core part of many critical applications (e.g., database management systems). Despite the large efforts
to parallelize it, the fact that it suffers from high data-dependencies vastly limits its performance. Multithreaded architectures
are emerging as the most demanding technology in leading-edge processors. These architectures include simultaneous multithreading,
chip multiprocessors, and machines combining different multithreading technologies. In this paper, we analyze the memory behavior
and improve the performance of the most recent parallel radix and quick integer sort algorithms on modern multithreaded architectures.
We achieve speedups up to 4.69× for radix sort and up to 4.17× for quicksort on a machine with 4 multithreaded processors
compared to single threaded versions, respectively. We find that since radix sort is CPU-intensive, it exhibits better results
on chip multiprocessors where multiple CPUs are available. While quicksort is accomplishing speedups on all types of multithreading
processers due to its ability to overlap memory miss latencies with other useful processing. 相似文献
9.
Galia Lavi Charles A. Dinarello Ron N. Apte Smadar Cohen 《Israel journal of chemistry》2005,45(4):457-464
A sustained delivery system for interleukin-1 receptor antagonist (IL-1Ra) may have great therapeutic and industrial potential due to the cytokine activity as an IL-1 inhibitor. Here, we investigated the capability of biodegradable polymeric microspheres to sustain the release and prolong the therapeutic efficacy of IL-1Ra. IL-1Ra was encapsulated within rapidly degrading poly(lactic/glycolic acid) PLGA RG502H microspheres, which showed a desirable release profile of IL-1Ra in vitro. Pharmacokinetic study in mice revealed elevated serum levels of the recombinant IL-1Ra (rIL-1Ra) for up to 8 days following subcutaneous injection of IL-1Ra microspheres. In comparison, the serum levels of rIL-1Ra following subcutaneous or intravenous bolus injection of the soluble cytokine decreased very rapidly; within 48 h no recombinant cytokine was detected in mice sera. The sustained delivery of rIL-1Ra for over two weeks was efficient in inhibiting IL-1ß-stimulated induction of serum IL-6. These results suggest that the present therapeutic protocol of daily bolus injections of the IL-1Ra may be replaced by a weekly injection of IL-1Ra within PLGA RG502H microspheres. 相似文献
10.
Proteolytic and acidifying properties of Streptococcus thermophilus strains isolated from yoghurt or cheeses were evaluated. Among 30 strains tested, 12 exhibited cell envelope-associated proteinase activity (PrtS+), three displayed a slight PrtS activity (PrtS+/?) and 15 were PrtS?, despite the presence of the corresponding gene (prtS) in eight of them. Sequencing of the prtS gene in four PrtS? and one PrtS+ strains revealed that the absence of PrtS activity in the PrtS? strain probably results from an alteration of the prtS regulation. The strains displaying the highest acidifying capacities were all PrtS+. All but one PrtS+ strains were phylogenetically close, as shown by the sequencing of their rDNA internal transcribed spacer (ITS) 16S-23S. More specifically, the high proteolytic and acidifying capacities are associated with the presence of a type II-ITS. 相似文献