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991.
P Anderlini D Przepiorka D Seong P Miller J Sundberg B Lichtiger F Norfleet KW Chan R Champlin M K?rbling 《Canadian Metallurgical Quarterly》1996,36(7):590-595
BACKGROUND: Apheresis of granulocyte-colony-stimulating factor (filgrastim)-mobilized blood stem cells from normal donors is now being used in place of a marrow harvest in transplantation. How the adverse effects of and charges for this procedure compare with those of the standard marrow harvest is not known. STUDY DESIGN AND METHODS: Forty consecutive normal subjects who received filgrastim 96 micrograms/kg) subcutaneously twice daily for 4 to 6 days in preparation for apheresis were monitored prospectively by clinical and laboratory evaluation. RESULTS: Sixty-two percent of the subjects required oral analgesics. None discontinued filgrastim prematurely. Bone pain (82%), headache (70%), fatigue (20%), and nausea (10%) were reported. Filgrastim caused a mean eightfold increase in neutrophil counts, a mean twofold increase in lymphocyte counts, a mean twofold rise in alkaline phosphatase and lactate dehydrogenase levels, and minor changes in serum potassium, magnesium, and uric acid. Adverse events and laboratory effects resolved within 7 days after apheresis. No apheresis stem cell donor required transfusion or hospitalization, and only one required an additional clinic visit after completion of apheresis. By comparison, a retrospective analysis of 33 normal marrow donors demonstrated that all received transfusion(s), 3 were hospitalized, 3 required additional clinic visits after the marrow harvest. The median total charges related to the two procedures were comparable (p = 0.43), although the charges were significantly lower for donors requiring only one apheresis procedure (p = 0.002). CONCLUSION: Filgrastim mobilization and apheresis of blood stem cells constitute a safe, well-tolerated, and comparable or less expensive alternative to the traditional marrow harvest. 相似文献
992.
Eddy current test (ECT) data collected from the in-service inspection (ISI) of pulled steam generator (SG) tubes were evaluated in terms of the primary water stress corrosion crack (PWSCC) length and depth evolution. After shot peening, the evaluated crack length and the number of cracks did not increase, but the Eddy current voltages that were related to the crack depth increased continuously. In the analysis of all the tubes of the plant, the evaluated crack lengths saturated at around 6 mm, while the voltage of the defects increased with time. As a result, shot peening was considered effective for suppressing crack length increase, but not so successful from the point of preventing crack deepening. It was also found that tube bundles that were susceptible to PWSCC were located in a special area depending on the steam generators of the analyzed plant. 相似文献
993.
Kwanjae Seong 《Journal of Mechanical Science and Technology》2002,16(7):959-965
Effective hydraulic conductivity of a statistically anisotropic heterogeneous medium is obtained for steady two-dimensional
flows employing stochastic analysis. Flow equations are solved up to second order and the effective conductivity is obtained
in a semi-analytic form depending only on the spatial correlation function and the anisotropy ratio of the hydraulic conductivity
field, hence becoming a true intrinsic property independent of the flow field. Results are obtained using a statistically
anisotropic Gaussian correlation function where the anisotropy is defined as the ratio of integral scales normal and parallel
to the mean flow direction. Second order results indicate that the effective conductivity of an anisotropic medium is greater
than that of an isotropic one when the anisotropy ratio is less than one and vice versa. It is also found that the effective
conductivity has upper and lower bounds of the arithmetic and the harmonic mean conductivities. 相似文献
994.
Seongwook Song Jun-Seok Lim Seong Joon Baek Koeng-Mo Sung 《Vehicular Technology, IEEE Transactions on》2002,51(3):613-616
In this article, the variable forgetting factor linear least squares algorithm is presented to improve the tracking capability of channel estimation. A linear channel model with respect to time change describes a time-varying channel more accurately than a conventional stationary channel model. To reduce the estimation error due to model mismatch, we incorporate the modified variable forgetting factor into the proposed algorithm. Compared to the existing algorithms-exponentially windowed recursive least squares algorithm with the optimal forgetting factor and linear least squares algorithm-the proposed method makes a remarkable improvement in a fast fading environment. The effects of channel parameters such as signal-to-noise ratio and fading rate are investigated by computer simulations 相似文献
995.
KC Chang SY Chung WS Chong JS Suh SH Kim HK Noh BW Seong HJ Ko KW Chun 《Canadian Metallurgical Quarterly》1993,266(2):992-1000
We investigated the possible involvement of the superoxide (.O2-) radical in alterations of vascular reactivity and phosphoinositide (PI) turnover in aortas from streptozotocin (STZ)-induced diabetic (4 week) rats. STZ treatment increased the maximal contractile response of the aorta to norepinephrine (NE), phenylephrine (PE) and high K+, whereas the sensitivity remained unaltered. Ca(++)-induced contractions in the presence of maximally effective concentrations of PE and K+ were also augmented after STZ treatment. The increased maximal response was associated with both decreased endothelium-dependent relaxation and increased NE-induced PI turnover. Pyrogallol (PYR), a potent .O2- generating agent, did not affect basal tone or PI turnover but, depending on concentrations, it significantly increased or decreased both the contractile response to PE and NE-induced PI turnover in control aorta. In contrast, PYR decreased NE-induced PI turnover in diabetic aorta. The malondialdehyde content of liver, serum and aorta, and of .O2- from aorta of diabetic rats, were increased significantly. Copper catalyzed oxidation of ascorbic acid resulted in contraction followed by relaxation, depending upon the ascorbic acid concentration in both control and diabetic aorta. Pretreatment with superoxide dismutase (300 U/ml) prevented the PYR-induced potentiation of the PE contraction, but not of NE+PYR-induced PI turnover in control aorta and decreased further NE+PYR-induced PI turnover in diabetic aorta. The present findings indicate that .O2- may be responsible, at least in part, for the impaired endothelial integrity, enhanced alpha adrenergic receptor-mediated PI turnover and augmented contractility, possibly through modification of calcium channels in STZ-induced short-term (4 week) diabetic rat aorta. 相似文献
996.
Sungjoo Suh Seong Soo Chun Myung-Hee Lee Sanghoon Sull 《Electronics letters》2003,39(6):514-515
An efficient image downconversion algorithm in the compressed domain for mixed field/frame-mode macroblocks is proposed. A 16 /spl times/ 16 field/frame-mode macroblock is converted into an 8 /spl times/ 8 reduced block in the discrete cosine transform (DCT) domain using a modified inverse DCT (IDCT) kernel. Experimental results show that the proposed algorithm provides the downconverted image quality similar to an existing method with significantly lower computational cost. 相似文献
997.
Soo Young Shin Hong Seong Park Sunghyun Choi Wook Hyun Kwon 《Wireless Communications, IEEE Transactions on》2007,6(8):2825-2830
In this paper, the performance of IEEE 802.15.4 ZigBee under the interference of IEEE 802.11b wireless local area network (WLAN) and/or Bluetooth is evaluated using an analytic model for the coexistence among ZigBee, WLAN, and Bluetooth. The packet error rate (PER) is evaluated, where the PER is obtained from the bit error rate (BER) and the collision time. The BER is obtained from the signal-to-interference-plus-noise ratio (SINR). Finally, the analytic results are validated by simulations. 相似文献
998.
999.
Measurements of thermal diffusivity of foil-shaped materials have been carried out using a photoirradiation-type AC calorimeter at room temperature. In this method the frequency effect, which is caused by heat loss from the sample to the environment, is readily detected in measurements of both amplitude and phase components of the AC temperature signal, Even though the chopping frequency is appropriate, the two diffusivities calculated from these two components differ from each other, Moreover, the difference between the two values increases when the chopping frequency increases. Simple vectorial calculation with the two components one from the amplitude and the other from the phase- permits the frequency ellect to be determined. The calculated result is the geometric average of the two diffusivities. This analytic method was tested with diamond film and SUS-304 foil. From these we confirmed that the vectorial analytic method gives similar diffusivity values for different frequencies indicating its reliability.Paper presented at the Twelfth Symposium on TherrmophysicaI Properties, June 19–24, 1994, Boulder, Colorado, U.S.A. 相似文献
1000.
An otoscope is traditionally used to examine the eardrum and ear canal. A diagnosis of otitis media (OM) relies on the experience of clinicians. If an examiner lacks experience, the examination may be difficult and time-consuming. This paper presents an ear disease classification method using middle ear images based on a convolutional neural network (CNN). Especially the segmentation and classification networks are used to classify an otoscopic image into six classes: normal, acute otitis media (AOM), otitis media with effusion (OME), chronic otitis media (COM), congenital cholesteatoma (CC) and traumatic perforations (TMPs). The Mask R-CNN is utilized for the segmentation network to extract the region of interest (ROI) from otoscopic images. The extracted ROIs are used as guiding features for the classification. The classification is based on transfer learning with an ensemble of two CNN classifiers: EfficientNetB0 and Inception-V3. The proposed model was trained with a 5-fold cross-validation technique. The proposed method was evaluated and achieved a classification accuracy of 97.29%. 相似文献