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21.
As an alternative to surgical splenectomy, partial splenic embolization was performed in seven children for hypersplenism manifested by splenomegaly, thrombocytopenia, leukopenia, and erythrocyte hemolysis. Within a few days, platelet and leukocyte counts rose significantly in all patients and were maintained in six of seven patients during a follow-up period of 9 to 69 months. Spleen size and abdominal distention also decreased significantly in all children. There were no infectious complications. 相似文献
22.
N Mamiya JR Goldenring Y Tsunoda IM Modlin K Yasui N Usuda T Ishikawa A Natsume H Hidaka 《Canadian Metallurgical Quarterly》1993,195(2):608-615
A novel Ca2+/calmodulin-dependent protein kinase II (CaM Kinase II) inhibitor, KN-93 potently inhibits gastric acid secretion from parietal cells. As previously reported (1), treatment of parietal cells with a selective inhibitor of CaM kinase II, KN-62 resulted in the inhibition of cholinergic-stimulated rabbit parietal cell secretion, whereas it failed to inhibit the histamine and forskolin response. In contrast effects of carbachol, histamine and forskolin were significantly inhibited by KN-93 with an IC50 of 0.15, 0.3 and 1 microM, respectively; these effects occurred without any changes in intracellular cyclic AMP and Ca2+ levels. In the present study we investigated the mechanism by which KN-93 acts upon the acid-secreting machinery of gastric parietal cells. Neither redistribution of the proton pump activity nor the morphological transformation were affected by KN-93. The drug only weakly inhibited the H+, K(+)-ATPase activity but strongly dissipated the proton gradient formed in the gastric membrane vesicles and reduced the volume of luminal space. Thus KN-93 acts at pH gradient formation whereas KN-62 acts only at CaM Kinase II. 相似文献
23.
This article is the second of two papers that review the field of spatially sensitive social scientific research into the links between social status and transport disadvantage. The first paper undertook a comprehensive review of the social scientific and transport planning literature to mark the level of development in the field and identify conceptual and methodological issues and constraints in this field of inquiry. The present article supports the advancement of socially and geographically sensitive transport research by opportunities for the development of more sophisticated spatial analytical methodologies. The approach we present is able to account for factors not previously addressed in either social or transport planning research, in particular the temporal dimensions of transport service accessibility. The article articulates the methodology through an empirical case study of socio-spatial transport disadvantage within the Gold Coast City. The article demonstrates that there are important theoretical and practical lessons to be gained for researchers and policy makers in addressing the social dimensions of transport and infrastructure provision. Further, the article argues that an attentiveness to new ways of combining and representing social and transport data-sets can promote policy relevant empirical social inquiry. The article also contributes in a productive way to the empirical knowledge of Australia's sixth-largest metropolitan area, which is often overlooked by urban scholars. 相似文献
24.
Enhanced Image Detection on an ARM based Embedded System 总被引:2,自引:0,他引:2
This paper presents a new technique for thedetection of Integrated Circuits within images of Printed Circuit Boards autonomouslyand without the need to be assisted by CAD data. The technique is a key partof a suite of algorithms targeted for an embedded System On Chip architecturebased on the ARM7 platform for real time detection of PCB images for diagnosticpurposes. The technique has a significant reduction in complexity when comparedto conventional approaches such as the Hough Transform. The reduction in complexitymakes the approach ideal for an embedded vision application suchas the one described in this paper. This paper presents the technique, thetarget embedded architecture and results showing the reduction in complexitywhen compared to a Hough Transform. 相似文献
25.
H.A.V. Evans 《Food microbiology》1985,2(1):19-22
The growth in beer of 15 brewery strains of Lactobacillus was detected using the automatic conductance measuring technique afforded by the Malthus 8 Growth Analyser. 0·15% ammonium chloride was added to the beer as an electrolyte and sodium acetate was used to raise the pH from ca 4·0 to 4·2 or above. No measurable responses were obtained using unmodified beer. The value of the method for development in routine brewery microbiological control is briefly discussed. 相似文献
26.
In this letter, we conduct analysis on the optimum design for RF-to-optical up-converter in coherent optical OFDM systems using an optical I/Q modulator. We first derive closed-form expressions for the nonlinearity in the optical I/Q modulator, represented by two-tone intermodulation products as a function of the bias point and modulation index. Additionally, we perform a numerical simulation to identify Q-penalty and the excess modulation insertion loss under various transmitter conditions. We find that in contrast to the direct-detected system, the optimal modulator bias point for the coherent system is pi, where the Q-penalty and excess loss are minimized 相似文献
27.
Moore J.R. Collings N. Crossland W.A. Davey A.B. Evans M. Jeziorska A.M. Komarcevic M. Parker R.J. Wilkinson T.D. Xu H. 《Photonics Technology Letters, IEEE》2008,20(1):60-62
Polarization-insensitivity is achieved in a reflective spatial light modulator by laying a quarter-wave plate (QWP) at the incident wavelength directly over the mirror pixels of a silicon backplane, and forming a nematic Freedrickcz cell over the QWP to modulate the reflected phase. To achieve the highest drive voltage from the available silicon process, a switched voltage common front electrode design is described, with variable amplitude square wave drive to the pixels to maintain constant root-mean-square drive and minimize phase fluctuations during the dc balance refresh cycle. The silicon has been fabricated and liquid-crystal-on-silicon cells both with and without the QWP assembled; applications include optically transparent switches for optical networks, beam steering for add-drop multiplexers for wavelength-division-multiplexing telecommunications, television multicast, and holographic projection. 相似文献
28.
Handley Simon J.; Evans Jonathan St. B. T.; Thompson Valerie A. 《Canadian Metallurgical Quarterly》2006,32(3):559
Under the suppositional account of conditionals, when people think about a conditional assertion, "if p then q," they engage in a mental simulation in which they imagine p holds and evaluate the probability that q holds under this supposition. One implication of this account is that belief in a conditional equates to conditional probability [P(q/p)]. In this paper, the authors examine a further implication of this analysis with respect to the wide-scope negation of conditional assertions, "it is not the case that if p then q." Under the suppositional account, nothing categorically follows from the negation of a conditional, other than a second conditional, "if p then not-q." In contrast, according to the mental model theory, a negated conditional is consistent only with the determinate state of affairs, p and not-q. In 4 experiments, the authors compare the contrasting predictions that arise from each of these accounts. The findings are consistent with the suppositional theory but are incongruent with the mental model theory of conditionals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
30.
The chondro-osseous junction has been the subject of considerable scrutiny, especially in terms of the fate and role of the terminally differentiated chondrocyte. Although it has been proposed that these cells change their phenotype and survive in the epiphysis, possibly as osteoblasts, evidence from a number of other studies suggests that chondrocytes may undergo apoptosis or programmed cell death. A useful test for programmed cell death is to end label DNA in cryosections using the commercial reagent ApopTag and detect antibody binding to fragmented DNA by epifluorescence; more direct assessments include examination of the nucleus for condensation of chromatin evaluating fragmentation through alkaline and pulsed field agarose gel electrophoresis of DNA, and measuring apoptosis by flow cytometry. We found that we could label cells in the proliferative and the hypertrophic region of the proximal tibial growth plate of the chick with ApopTag. Most of the chondrocytes in the hypertrophic region were labeled by the reagent; in contrast, few proliferative chondrocytes were stained by the end-labeling procedure. Both agarose and pulsed field electrophoresis were used to confirm that there was fragmentation of chondrocyte DNA. Alkaline gel electrophoresis indicated that there was more fragmentation of DNA from hypertrophic cells than from proliferative chondrocytes. Further evidence in support of apoptosis was provided by electron microscopic observation of cells in the hypertrophic region of the growth plate. We noted that many of the cells in this region of the growth plate appeared to be undergoing programmed cell death since their nuclei contained condensed chromatin. Finally, we used flow cytometry to analyze chondrocytes isolated from the proliferating and hypertrophic regions of the growth plate for apoptosis. Dual parameteric flow cytometric contour plots of Hoechst and 7-amino-actinomycin D fluorescence showed that abut 8% of cells in the plate were apoptotic. Most of these cells were in hypertrophic cartilage. In summary, the results of this investigation indicate that chondrocytes terminate their life history by apoptosis. While it is possible that the terminal labeling studies may overestimate the number of cells undergoing this event, the data lend credence to the view that cells are removed from the epiphysis through apoptosis. If this is the case, then chondrocytes probably enter the terminal phase of their life as fully functioning cells and genomic, and/or local environmental conditions provide termination signals that initiate events that lead to programmed cell death. 相似文献