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211.
Kudo N  Toyama T  Mitsumoto A  Kawashima Y 《Lipids》2003,38(5):531-537
Regulation of palmitoyl-CoA chain elongation (PCE) and its contribution to oleic acid formation were investigated in rat liver in comparison with stearoyl-CoA desaturase (SCD). Hepatic PCE activity was induced by the administration of 20% wt/vol glucose or fructose in the drinking water of normal rats. In streptozotocin-induced diabetic rats, the activities of both PCE and SCD were suppressed, and fructose, but not glucose, feeding caused an increase in the activities of both enzymes. Treatment of normal rats with clofibric acid in combination with carbohydrate further increased PCE, but not SCD, acitivity. FA analysis of hepatic lipids revealed that the proportion of oleic acid (18∶1n−9) increased upon administration of carbohydrate or clofibric acid. The treatment of rats with clofibric acid in combination with carbohydrate greatly increased the proportion of 18∶1n−9. A significant correlation was observed between PCE activity and the hepatic proportion of 18∶1n−9 (r 2=0.874, Po0.01), whereas the relationship between SCD activity and the proportion of 18∶1n−9 was not significant (r 2=0.552, P>0.05). Taken together, these results suggest that carbohydrate induces PCE as well as SCD activity to increase the hepatic 18∶1 content in rat liver, and the increased PCE activity seems to be responsible for the further increase in 18∶1n−9 when carbohydrate is administered in combination with clofibric acid. FA are designated by the number of carbon atoms and double bonds  相似文献   
212.
Regulatory T cells (Tregs) suppress immune responses and maintain immunological self-tolerance and homeostasis. We currently investigated relationships between skin barrier condition and Treg behavior using skin barrier-disrupted mice. Skin barrier disruption was induced by repeated topical application of 4% sodium dodecyl sulfate (SDS) on mice. The number of CD4+ forkhead box protein P3 (Foxp3)+ Tregs was higher in 4% SDS-treated skins than in controls. This increasing was correlated with the degree of acanthosis. The numbers of interleukin (IL)-10+ and transforming growth factor (TGF)-β+ Tregs also increased in 4% SDS-treated skins. Localization of IL-33 in keratinocytes shifted from nucleus to cytoplasm after skin barrier disruption. Notably, IL-33 promoted the migration of Tregs in chemotaxis assay. The skin infiltration of Tregs was cancelled in IL-33 neutralizing antibody-treated mice and IL-33 knockout mice. Thus, keratinocyte-derived IL-33 may induce Treg migration into barrier-disrupted skin to control the phase transition between healthy and inflammatory conditions.  相似文献   
213.
A 100-Msps sampling analog-to-digital converter chip set   总被引:1,自引:0,他引:1  
The authors describe a 100-Msps sampling analog-to-digital converter (ADC) chip set that can be used for a wideband high-resolution digital storage oscilloscope (DSO). A high conversion rate and a 500-MHz sampling bandwidth with an 8-b effective resolution are obtained by a combination of three Si-bipolar chips and two GaAs-diode chips. the ADC uses a pipelined two-step subranging architecture that uses two cascade wideband track-and-hold (T/H) circuits. The design features of the T/H circuits and the residual amplifier are also presented  相似文献   
214.
Electroluminescence (EL) properties of AlN:Tb thin film EL device (TFELD) prepared on a glass substrate by a rf-magnetron sputtering method have been studied. The AlN:Tb emission layer consists of hexagonal (110)-oriented poly-crystals of AlN with a high transparency in visible region. Four emission peaks originating from 5D→ 7F j (j = 6, 5, 4, 3) transitions of Tb3+ were found in both photoluminescence (PL) and EL spectra of the AlN:Tb thin film. The peak emission intensity of the 5D→ 7F6 transitions is almost the same magnitude with that of the 5D→ 7F5 transitions, being largely different from the intensity ratio of Tb3+in other host materials.  相似文献   
215.
We present a reasoning model based on psychological similarity and discuss its application to database interfaces. In our approach, relationships in a relational type of database are translated to similarity relationships between data through a psychological model of similarity. The siimilarity relationships are integrated into a network-type of knowledge base. A function of information propagation in the knowledge base, based on a psychological model of stimulus generalization, is implemented in order to enable a similarity-based search through the database. Using this information propagation function, the computer also determines the generic kind of question it should next pose to the user. The user is allowed to give indefinite answers which reflect lack of knowledge or knowledge imprecision, and also to take control of the dialog when necessary. Through this dialog process, the interface system aids the user in specifying requests for relevant data, as well as in retrieving data from the database.  相似文献   
216.
We report here a patient with acute myeloid leukemia (AML) expressing both T- and B-lymphoid-associated antigens. The leukemia cells in this case had rearrangements of not only immunoglobulin heavy-chain but also T-cell-receptor beta- and delta-chain genes. Although a relatively large number of AML patients with lymphoid markers have been reported, only about a dozen AML patients expressing both T- and B-lymphoid markers have been reported so far.  相似文献   
217.
Public spending on computer centers in rural Indian public schools raise questions about the value of expensive modern technology in extremely resource-strapped environments. Arguments for or against providing computers in low-income schools have appeared in policy circles, academia, teacher conferences, and philanthropic discussions, with passionate rhetoric from all sides. We present the results of a qualitative study of computer-aided learning centers in schools catering primarily to Below Poverty Line (BPL) families in four districts of rural Karnataka, South India. Here, we held a series of open-and close-ended discussions with parents of children from these schools on issues such as aspirations, quality of schooling, and the perception of computers more generally. The research reveals a range of voices on hopes for the next generation, perceived value of computer courses and higher education, and the perceived changes in villages after the arrival of computers in their local schools. It emerges that for many parents, the computer has an immense symbolic value—separate from its functional value—that is tied to social and economic ascendancy. We find that this symbolic value derives from associations that parents imbibe from their various interactions with people using computers in a range of situations. We find in our interviews a heightened sense of mystique over the technology and its potential, across people with varying levels of first-hand experience and understanding of computers. We find that notions of change and hope are situated within an environment of great fear about the future of agriculture. We argue here that this, alongside a widespread existing discourse about computers in media and public life in India, mostly emerging from urban middle-classes ideas around technology, help spur a strong sense of expectation that the computers can dramatically change social prospects even among the poorest and most excluded. From competing with English as the gateway to power, to impacting dowry costs for female youth, interviews show a myriad of expectations from technology, creating what we see as a strong case for a nuanced look at the discourse and mythology of computers and technology in developing regions.
Kentaro ToyamaEmail:

Joyojeet Pal   is a Research Associate at the Center for Information and Society at the University of Washington. His recent research is primarily in the aspirational environment around technology projects in the developing world. He can be reached at joyojeet@gmail.com. Meera Lakshmanan   is an independent consultant on technology and education issues in Bangalore. She can be reached at meeragargi@gmail.com. Kentaro Toyama   is the Assistant Managing Director of Microsoft Research India, Bangalore. He can be reached at kentaro.toyama@microsoft.com.  相似文献   
218.
In order to develop a proof procedure of multi-agent autoepistemic Logic (MAEL), a natural framework to formalize belief and reasoning including inheritance, persistence, and causality, we introduce a method that translates a MAEL theory into a logic program with integrity constraints. It is proved that there exists one-to-one correspondence between extensions of a MAEL theory and stable models of a logic program translated from it. Our approach has the following advantages: (1) We can obtain all extensions of a MAEL theory if we compute all stable models of the translated logic program. (2) We can fully use efficient techniques or systems for computing stable models of a logic program. We also investigate the properties of reasoning in MAEL through this translation. The fact that the extension computing problem can be reduced to the stable model computing problem implies that there are close relationships between MAEL and other formalizations of nonmonotonic reasoning.  相似文献   
219.
220.
The aim of this study was to assess the usefulness of 99Tcm-tetrofosmin for detecting tumours of the lungs and adjacent structures and to compare the results with those for 201Tl. In the 18 patients studied, there were 30 lesions in total. Dual-isotope SPET acquisitions were performed 10 min and 3 h after the administration of 99Tcm-tetrofosmin and 201Tl. Image quality and semi-quantitative parameters were evaluated for both tracers. All lesions were detected by the two radiopharmaceuticals on both the early and delayed images. In seven patients, the image quality of 99Tcm-tetrofosmin was better than that of 201Tl. For the detection of metastatic lymph nodes, the delayed 201Tl and the early 99Tcm-tetrofosmin images were superior. No significant difference was observed between the uptake ratios of the two tracers. 99Tcm-tetrofosmin showed significantly (P < 0.001) higher washout than 201Tl from both the lesions and normal lungs, although washout of 201Tl from normal lungs was significantly higher than that from the lesions. In conclusion, 99Tcm-tetrofosmin may be helpful for detecting tumours of the lungs and adjacent structures, but has limited applicability in differentiating between malignant and benign tumours and may not be used instead of 201Tl to detect malignant tumours of the lungs.  相似文献   
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