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31.
A series of 8 peptides derived from the amino acid sequence accommodating the plasmin cleavage site in vitronectin were synthesized and used to map its binding site for the type I plasminogen activator inhibitor (PAI-1). This mapping assigned the inhibitor binding site to the K348-R370 region with high affinity recognition elements within the K348-R357 sequence. These results account for our previous finding that cleavage of the R361-S362 bond by plasmin significantly reduces the affinity between PAI-1 and vitronectin, since it splits the PAI-1 binding site in two. Furthermore, in the case of the two-chain form of vitronectin, this cleavage detaches the S362-R379 peptide which provides some of the affinity elements for the binding of PAI-1.  相似文献   
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Immunocompromised hosts have defects in their immune system that make them at risk of developing a variety of infections. In addition, these persons may develop a wide variety of noninfectious disease processes that involve the lung. These disorders may be caused by the underlying disease process. This may be seen with the development of metastatic disease from the underlying neoplasm, or it may represent the development of a malignancy secondary to therapy, as is seen with posttransplant lymphoproliferative disease. The abnormalities may be a result of the therapy used to treat the patients, as is seen with radiation injury to the lung and drug toxicity. Pulmonary edema may occur and be from a wide variety of causes. All of these disease processes may simulate an infectious process and must be differentiated from infection to allow proper therapeutic intervention.  相似文献   
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Photo- and charge-carrier-induced ion migration is a major challenge when utilizing metal halide perovskite semiconductors for optoelectronic applications. For mixed iodide/bromide perovskites, the compositional instability due to light- or electrical bias induced phase-segregation restricts the exploitation of the entire bandgap range. Previous experimental and theoretical work suggests that excited states or charge carriers trigger the process, but the exact mechanism is still under debate. To identify the mechanism and cause of light-induced phase-segregation phenomena, the full compositional range of methylammonium lead bromide/iodide samples are investigated, MAPb(BrxI1-x)3 with x = 0…1, by simultaneous in situ X-ray diffraction (XRD) and photoluminescence (PL) spectroscopy during illumination. The quantitative comparison of composition-dependent in situ XRD and PL shows that at excitation densities of 1 sun, only the initial stage of photo-segregation is rationalized with the previously established thermodynamic models. However, a progression of the phase segregation is observed that is rationalized by considering long-lived accumulative photo-induced material alterations. It is suggested that (additional) photo-induced defects, possibly halide vacancies and interstitials, need to be considered to fully rationalize light-induced phase segregation and anticipate the findings to provide crucial insight for the development of more sophisticated models.  相似文献   
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This article is a selective theory-driven review that synthesizes recent neuroscience findings concerning mental workload during complex cognition from the perspective of a functional resource theory called 3CAPS, focusing on the concept of capacity utilization . Capacity utilization refers to the proportion of resources that is being consumed in a given time interval in a given cognitive system. This definition integrates the dynamic effects of (a) the computational demand imposed by a task, and (b) the resource supply in an individual that is available to meet that demand. The analysis reveals that the functional relations between capacity utilization and measures of neural activity are similar across three different cognitive systems (language comprehension, visuospatial processing and executive processing). The measures of neural activity include functional neuroimaging, pupillary dilation and event-related potentials. The construct of capacity utilization provides a mapping between a functional architecture of cognition and aspects of its neural implementation.  相似文献   
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Abstract

Legislation which required open space to be provided at the time of subdivision has failed to regulate the quality and encourage full subsequent use of such reserves. Councils most affected by this legislation are usually located in rapidly developing outer suburbs and seldom possess or allocate sufficient resources to devote to the proper development of these reserves.  相似文献   
39.
Determination of telomere length is traditionally performed by Southern blotting and densitometry, giving a mean telomere restriction fragment (TRF) value for the total cell population studied. Fluorescence in situ hybridization (FISH) of telomere repeats has been used to calculate telomere length, a method called quantitative (Q)-FISH. We here present a quantitative flow cytometric approach, Q-FISHFCM, for evaluation of telomere length distribution in individual cells based on in situ hybridization using a fluorescein-labeled peptide nucleic acid (PNA) (CCCTAA)3probe and DNA staining with propidium iodide. A simple and rapid protocol with results within 30 h was developed giving high reproducibility. One important feature of the protocol was the use of an internal cell line control, giving an automatic compensation for potential differences in the hybridization steps. This protocol was tested successfully on cell lines and clinical samples from bone marrow, blood, lymph nodes and tonsils. A significant correlation was found between Southern blotting and Q-FISHFCMtelomere length values ( P = 0.002). The mean sub-telomeric DNA length of the tested cell lines and clinical samples was estimated to be 3.2 kbp. With the Q-FISHFCMmethod the fluorescence signal could be determined in different cell cycle phases, indicating that in human cells the vast majority of telomeric DNA is replicated early in S phase.  相似文献   
40.
Three experiments investigated the effects of negation during on-line language processing. It was hypothesized that negation of a noun (e.g., no bread) would affect the activation level of the mental representation of that noun. Experiment 1 manipulated the location of the negation in sentences that were followed by a probe recognition task. Subjects were slower to indicate that a probe had been in the sentence when the probe corresponded to a negated noun. Experiment 2 replicated these results with a probe naming task. Experiment 3 replicated the result that reading the phrase no bread inhibits responses to bread in the probe task but found no evidence of inhibition of the response to an associate probe, such as butter. The results of these three studies suggest that negation affects the discourse focus of a noun phrase, and hence the activation level of its representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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