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51.
52.
Compared to 21 operated and 14 nonoperated controls, 36 male Sprague-Dawley albino rats with small bilateral lesions in the anteroventral caudate nucleus or the rostral substantia nigra were significantly impaired in the acquisition of 1-way active avoidance, passive avoidance requiring the inhibition of the previously acquired 1-way response, and shuttle-box avoidance. Ss with nigral lesions took significantly more trials to criterion than Ss with caudate lesions on 1-way avoidance. Results are considered in terms of the intimate anatomical and neurochemical relationships between these structures, and a circuit of structures involved in avoidance learning is suggested. (34 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
53.
To reconcile past research based on reactance theory that found convergence of evaluations of alternatives prior to a choice, and research based on choice certainty theory that found divergence, it was proposed that convergence occurs in private evaluations. According to this interpretation, the freedom to choose a nonpreferred alternative is threatened by the overt expression of a preference that involves commitment but is not threatened by the private holding of a preference. Two experiments were conducted with 180 female undergraduates to test this interpretation. The studies used the procedure in which D. E. Linder and K. A. Crane (see record 1970-15980-001) and Linder et al (see record 1972-02217-001) found convergence of overtly expressed evaluations. The present experiments found divergence when evaluations were made privately; that is, supposedly without the experimenter being aware of the nature of the evaluations. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
Interpersonal attraction in exchange and communal relationships.   总被引:1,自引:0,他引:1  
Communal relationships, in which the giving of a benefit in response to a need for the benefit is appropriate, are distinguished from exchange relationships, in which the giving of a benefit in response to the receipt of a benefit is appropriate. Based on this distinction, it was hypothesized that the receipt of a benefit after the person has been benefited leads to greater attraction when an exchange relationship is preferred and decreases attraction when a communal relationship is desired. These hypotheses were supported in Exp I, which used 96 male undergraduates. Exp II, which used a different manipulation of exchange vs communal relationships with 80 female undergraduates, supported the hypotheses that (a) a request for a benefit after the S is aided by the other leads to greater attraction when an exchange relationship is expected and decreases attraction when a communal relationship is expected, and (b) a request for a benefit in the absence of prior aid from the other decreases attraction when an exchange relationship is expected. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
55.
The development of affordable, effective, and environmentally friendly barrier fabrics is a current goal in antimicrobial textile development. The discovery of new routes to achieve non-toxic naturally occurring molecules with antimicrobial activity is of interest in the development of materials that promote wound healing, improve hygiene, and offer protection against nosocomial infection. Highly cleaned and sterile unbleached cotton has constituents that produce hydrogen peroxide at levels commensurate with those that favor cell signaling in wound healing. Here, we show the antimicrobial and antiviral properties of spunlaced griege cotton-containing nonwovens treated with ascorbic acid formulations. The mechanism of action occurs through the promotion of enhanced hydrogen peroxide activity. The levels of hydrogen peroxide activity afford antimicrobial activity against Gram-negative and Gram-positive bacteria and antiviral activity against MS2 bacteriophages. Spun-bond nonwoven unbleached cotton was treated with ascorbic acid using traditional pad-dry-cure methods. An assessment of antibacterial and antiviral activity against Staphylococcus aureus, Klebsiella pneumoniae, and MS2 bacteriophages with the AATCC 100 test method showed a 99.99% inhibitory activity. An approach to the covalent attachment of ascorbic to cellulose through citric acid crosslinking chemistry is also discussed. Thus, a simple, low-cost approach to antimicrobial and antiviral cotton-based nonwovens applicable to dressings, nosocomial barrier fabrics, and face masks can be adopted by combining ascorbic acid with spunlace greige cotton nonwoven fabrics.  相似文献   
56.
Wireless Personal Communications - In this article, the computational complexity reduction of zero forcing (ZF) and minimum mean square error (MMSE) detection is presented for the uplink multiple...  相似文献   
57.
Pepsin refluxate is considered a risk factor for laryngopharyngeal carcinogenesis. Non-acidic pepsin was previously linked to an inflammatory and tumorigenic effect on laryngopharyngeal cells in vitro. Yet there is no clear evidence of the pepsin-effect on a specific oncogenic pathway and the importance of pH in this process. We hypothesized that less acidic pepsin triggers the activation of a specific oncogenic factor and related-signalling pathway. To explore the pepsin-effect in vitro, we performed intermittent exposure of 15 min, once per day, for a 5-day period, of human hypopharyngeal primary cells (HCs) to pepsin (1 mg/mL), at a weakly acidic pH of 5.0, a slightly acidic pH of 6.0, and a neutral pH of 7.0. We have documented that the extracellular environment at pH 6.0, and particularly pH 7.0, vs. pH 5.0, promotes the pepsin-effect on HCs, causing increased internalized pepsin and cell viability, a pronounced activation of EGFR accompanied by NF-κB and STAT3 activation, and a significant upregulation of EGFR, AKT1, mTOR, IL1β, TNF-α, RELA(p65), BCL-2, IL6 and STAT3. We herein provide new evidence of the pepsin-effect on oncogenic EGFR activation and its related-signaling pathway at neutral and slightly acidic pH in HCs, opening a window to further explore the prevention and therapeutic approach of laryngopharyngeal reflux disease.  相似文献   
58.
Patients with end-stage sarcoidosis have now undergone lung transplantation successfully with good short-term and intermediate-term results. Lung transplantation for sarcoidosis requires several considerations unique to this disease. Selection of pulmonary sarcoidosis patients for transplantation requires that medical therapy has been exhausted. This may involve the use of corticosteriods and alternative medications. Causes of pulmonary dysfunction other than pulmonary sarcoidosis, such as bronchiectasis and myocardial sarcoidosis, must be excluded before candidates are considered for transplantation. The extent and severity of extrapulmonary disease must also be assessed and may preclude lung transplantation. The presence of mycetomas is considered a relative contra-indication by some transplant centres and an absolute contra-indication by others. Relatively few patients with pulmonary sarcoidosis have undergone transplantation and, therefore, there are few data on outcome. Sarcoidosis frequently recurs in the allograft, but rarely causes symptoms or pulmonary dysfunction. More severe acute rejection episodes may occur in sarcoidosis transplant recipients, although at present there is no evidence of an increased risk of obliterative bronchiolitis or increased mortality.  相似文献   
59.
Alcohol use may increase HIV sexual risk behavior, although findings have varied across study populations and methods. Using event-level data from 1,712 seronegative men who have sex with men, the authors tested the hypothesis that social context would moderate the effect of alcohol consumption on unprotected anal sex (UAS). For encounters involving a primary partner, rates of UAS did not vary as a function of alcohol use. However, consumption of 4 or more drinks tripled the likelihood of UAS for episodes involving a nonprimary partner. Thus, the effects of alcohol vary according to the context in which it is used. Interventions to reduce substance-related risk should be tailored to the demands of maintaining sexual safety with nonprimary partners. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
60.
C. Judson King 《Drying Technology》2013,31(5-7):1221-1240
ABSTRACT

Retention or loss of trace volatile compounds during spray drying can be vital for product quality. Examples of cases where loss or retentions of volatile substances are important include retention of balanced flavor and aroma in food products, removal of odiferous substances, and control of the release of volatile organic compounds to the atmosphere. Factors and mechanisms determining losses of these substances are reviewed. Losses can occur during atomization, from undisturbed drops and as a result of morphological development. On the basis of this insight, several avenues for controlling the retention of volatile substances are identified and analyzed. These include control of atomizer pressure or rotation speed, choice of spray angle, configuration of air input, lteration of the air temperature profile, feed concentration, the presence of an oil phase and/or suspended solids, foaming of the feed, feed composition, and steam blanketing of the atomizer.

The quality of a spray-dried product can be strongly affected by the presence or absence of volatile compounds that were present in the feed to the spray dryer. For example, spray-dried coffee and tea have suffered from a air and thereby avoid bubble formation, expansion and bursting for deaerated feeds (20). This approach produces a product with high bulk density. If that result is cceptable, then it should also be a way of precluding volatiles loss due to morphological development.  相似文献   
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