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991.
992.
L. L. Jacoby and K. Whitehouse (1989) observed that false recognition of new test words was biased by the nature and duration of preceding context words. With very brief exposures to context words, participants were more likely to call a test item "old" when the prior context word was identical than when there was a mismatch. At longer durations, the reverse pattern was obtained. In the present experiment, test items were preceded by the rapid visual presentation of 7 supraliminal context items, 1 of which might or might not match the test item. Participants either looked for matches (high salience) or tried to remember the context items (low salience). The results closely resemble those for long and short exposure durations, suggesting that the crucial variable is the salience of matches rather than perceptual subliminality of context items. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
MK Jeffcoat MS Reddy S Haigh W Buchanan MJ Doyle MP Meredith SL Nelson MB Goodale KR Wehmeyer 《Canadian Metallurgical Quarterly》1995,66(5):329-338
Systemic non-steroidal anti-inflammatory drugs (NSAIDs) have been shown to reduce alveolar bone loss in periodontitis. This study assesses the efficacy of a topical NSAID rinse, containing ketorolac tromethamine as the active agent. Adult periodontitis patients (n = 55) were studied in this 6-month randomized, double blind, parallel, placebo and positive-controlled study. Each patient had a least 3 sites at high risk for bone loss as assessed by low dose bone scan. Groups, balanced for gender, were assigned to one of three regimens: bid ketorolac rinse (0.1%) with placebo capsule; 50 mg bid flurbiprofen capsule (positive control) with placebo rinse; or bid placebo rinse and capsule. Prophylaxes were provided every 3 months. Monthly examinations assessed safety, gingival condition, and gingival crevicular fluid PGE2. Standardized radiographs were taken at baseline and at 3 and 6 months for digital subtraction radiography. A significant loss in bone height was observed during the study period in the placebo group (-0.63 +/- 0.11; P < 0.001), but not in the flurbiprofen (-0.10 +/- 0.12; P = 0.40) or ketorolac rinse (+0.20 +/- 0.11 mm; P = 0.07) groups. Nested ANOVA revealed that ketorolac and flurbiprofen groups had less bone loss (P < 0.01) and reduced gingival crevicular fluid PGE2 levels (P < 0.03) compared to placebo. ANOVA suggests (P = 0.06) that ketorolac rinse preserved more alveolar bone than systemic flurbiprofen at the dose regimens utilized. These data indicate that ketorolac rinse may be beneficial in the treatment of adult periodontitis. 相似文献
994.
AC Carvalho JF Lima AC Soares SL Lopes CM Silva J Bocanegra 《Canadian Metallurgical Quarterly》1994,63(2):117-119
A two-year-old male child presenting anomalous origin of the left coronary artery diagnosed by Doppler echocardiography and confirmed by angiography developed an ischemic stroke, which is a rare event in this situation. He [correction of She] had good recovery of the neurological deficit and his anomalous artery was successfully reimplanted. 相似文献
995.
KR Kralovich L Li TA Hembrough DJ Webb LR Karns SL Gonias 《Canadian Metallurgical Quarterly》1998,17(8):845-854
Cytokeratin 8 (CK8) is an intermediate filament protein that penetrates to the external surfaces of breast cancer cells and is released from cells in the form of soluble heteropolymers. CK8 binds plasminogen and tissue-type plasminogen activator (t-PA) and accelerates plasminogen activation on cancer cell surfaces. The plasminogen-binding site is located at the C-terminus of CK8. In this study, we prepared GST-fusion proteins which contained either 174 amino acids from the C-terminus of CK8 (CK8f) or 134 amino acids from the C-terminus of CK18 (CK18f). A third GST-CK fusion protein was identical to CK8fexcept that the C-terminal lysine was mutated to glutamine (CK8fK483Q). CK8f bound plasminogen; the K(D) was 0.5 microM. Binding was completely inhibited by epsilonACA. CK8fK483Q also bound plasminogen, albeit with decreased affinity (K(D) approximately 1.5 microM). CK18f did not bind plasminogen at all. All three fusion proteins bound t-PA equivalently, providing the first evidence that CK18 may function as a t-PA receptor, t-PA and plasminogen cross-competed for binding to CK8f. Thus, t-PA and plasminogen cannot bind to the same CK8f monomer simultaneously. Nevertheless, CK8f still promoted plasminogen activation, probably reflecting the fact that CK8f was purified in dimeric or tetrameric form. These studies demonstrate that CK8 may promote plasminogen activation by t-PA only when present in an oligomerized state. CK18 may participate in the oligomer, together with CK8, based on its ability to bind t-PA. 相似文献
996.
997.
DB Short KW Trotter D Reczek SM Kreda A Bretscher RC Boucher MJ Stutts SL Milgram 《Canadian Metallurgical Quarterly》1998,273(31):19797-19801
The function of the cystic fibrosis transmembrane conductance regulator (CFTR) as a Cl- channel in the apical membrane of epithelial cells is extensively documented. However, less is known about the molecular determinants of CFTR residence in the apical membrane, basal regulation of its Cl- channel activity, and its reported effects on the function of other transporters. These aspects of CFTR function likely require specific interactions between CFTR and unknown proteins in the apical compartment of epithelial cells. Here we report that CFTR interacts with the recently discovered protein, EBP50 (ERM-binding phosphoprotein 50). EBP50 is concentrated at the apical membrane in human airway epithelial cells, in vivo, and CFTR and EBP50 associate in in vitro binding assays. The CFTR-EBP50 interaction requires the COOH-terminal DTRL sequence of CFTR and utilizes either PDZ1 or PDZ2 of EBP50, although binding to PDZ1 is of greater affinity. Through formation of a complex, the interaction between CFTR and EBP50 may influence the stability and/or regulation of CFTR Cl- channel function in the cell membrane and provides a potential mechanism through which CFTR can affect the activity of other apical membrane proteins. 相似文献
998.
The activities of six new fluoroquinolones (moxifloxacin, grepafloxacin, gatifloxacin, trovafloxacin, clinafloxacin, and levofloxacin) compared with those of sparfloxacin and ciprofloxacin with or without reserpine (20 microg/ml) were determined for 19 Streptococcus pneumoniae isolates, 5 Haemophilus sp. isolates, and 10 Pseudomonas aeruginosa isolates with decreased susceptibility to ciprofloxacin from patients with clinically confirmed lower respiratory tract infections. Based upon the MICs at which 50% of isolates were inhibited (MIC50s) and MIC90s, the most active agent was clinafloxacin, followed by (in order of decreasing activity) trovafloxacin, moxifloxacin, gatifloxacin, sparfloxacin, and grepafloxacin. Except for clinafloxacin (and gatifloxacin and trovafloxacin for H. influenzae), none of the new agents had improved activities compared with that of ciprofloxacin for P. aeruginosa and H. influenzae. A variable reserpine effect was observed for ciprofloxacin and S. pneumoniae; however, for 9 of 19 (47%) isolates the MIC of ciprofloxacin was decreased by at least fourfold, suggesting the presence of an efflux pump contributing to the resistance phenotype. The laboratory parC (Ser79) mutant strain of S. pneumoniae required eightfold more ciprofloxacin for inhibition than the wild-type strain, but there was no change in the MIC of sparfloxacin and only a 1-dilution increase in the MICs of the other agents. For efflux pump mutant S. pneumoniae the activities of all the newer agents, except for levofloxacin, were reduced. Except for clinafloxacin, all second-step laboratory mutants required at least 2 microg of all fluoroquinolones per ml for inhibition. 相似文献
999.
James W. Davis Alexander M. Morison David D. Woods 《Machine Vision and Applications》2007,18(1):41-64
In current video surveillance systems, commercial pan/tilt/zoom (PTZ) cameras typically provide naive (or no) automatic scanning
functionality to move a camera across its complete viewable field. However, the lack of scene-specific information inherently
handicaps these scanning algorithms. We address this issue by automatically building an adaptive, focus-of-attention, scene-specific
model using standard PTZ camera hardware. The adaptive model is constructed by first detecting local human activity (i.e.,
any translating object with a specific temporal signature) at discrete locations across a PTZ camera’s entire viewable field.
The temporal signature of translating objects is extracted using motion history images (MHIs) and an original, efficient algorithm
based on an iterative candidacy-classification-reduction process to separate the target motion from noise. The target motion
at each location is then quantified and employed in the construction of a global activity map for the camera. We additionally
present four new camera scanning algorithms which exploit this activity map to maximize a PTZ camera’s opportunity of observing
human activity within the camera’s overall field of view. We expect that these efficient and effective algorithms are implementable
within current commercial camera systems. 相似文献
1000.
Balsis Steve; Gleason Marci E. J.; Woods Carol M.; Oltmanns Thomas F. 《Canadian Metallurgical Quarterly》2007,22(1):171
Many of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV; American Psychiatric Association, 1994) personality disorder (PD) diagnostic criteria focus on a younger social and occupational context. The absence of age-appropriate criteria for older adults forces researchers and clinicians to draw conclusions based on existing criteria, which are likely inadequate. To explore which DSM-IV PD criteria contain age group measurement bias, the authors report 2 analyses of data on nearly 37,000 participants, ages 18-98 years, taken from a public data set that includes 7 of the 10 PDs (antisocial, avoidant, dependent, histrionic, obsessive-compulsive, paranoid, and schizoid). The 1st analysis revealed that older age groups tend to endorse fewer PD criteria than younger age groups. The 2nd analysis revealed that 29% of the criteria contain measurement bias. Although the latent variable structure for each PD was quite similar across younger and older age groups, some individual criteria were differentially endorsed by younger and older adults with equivalent PD pathology. The presence of measurement bias for these criteria raises questions concerning the assessment of PDs in older adults and the interpretation of existing data. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献