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101.
The goal of these studies was to investigate the potential anticancer properties of two naturally occurring plant sources and two manufactured synthetic forms of vitamin E, i. e., RRR-alpha-tocopherol (alphaT), RRR-gamma-tocopherol (gammaT), all-rac-alpha-tocopherol (all-rac-alphaT), and all-rac-alpha-tocopheryl acetate (all-rac-alphaTAc) in breast cancer models. Vitamin E compounds were evaluated in vitro for inhibition of colony formation and induction of apoptosis in human MDA-MB-435 and MCF-7 breast cancer cells and murine 66cl-4 mammary cancer cells and in vivo for ability to reduce tumor growth and lung and lymph node metastases using the transplantable syngeneic BALB/c mouse 66cl-4-GFP mammary cancer model. gammaT inhibited colony formation and induced apoptosis in all three cancer cell lines. alphaT and all-rac-alphaT were less effective and all-rac-alphaTAc was ineffective. gammaT-induced apoptosis was correlated with activation of caspases-8 and -9 and down-regulation of protein expression of c-FLIP and survivin. In vivo study 1 analyses showed that all-rac-alphaT and all-rac-alphaTAc significantly inhibited tumor growth and inhibited both visible and microscopic size lung metastases. In vivo study 2 analyses showed that alphaT and gammaT reduced tumor growth, but only gammaT reduced tumor growth significantly in comparison to control. In conclusion, synthetic, but not natural, vitamin E exhibits promising anti-cancer properties in vivo.  相似文献   
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103.
Objective: To directly compare estimates of potential depressive disorders and clinically significant depressive symptoms using the Patient Health Questionnaire-9 (PHQ-9) and Older Adult Health and Mood Questionnaire (OAHMQ) among participants with spinal cord injury (SCI). Research Design: 727 participants from a hospital in the Southeastern United States were administered the PHQ-9 and OAHMQ during a follow-up survey. We compared the rates of depressive disorders using cutoff scores and diagnostic criteria for each instrument. No independent psychiatric diagnostic interviews were conducted. Results: The PHQ-9 and OAHMQ were significantly correlated (r = .78), and both were correlated with satisfaction with life (r = ?.48, ?.54). Using recommended diagnostic scoring procedures, 10.7% of participants met the diagnostic criteria for major depressive disorder with the PHQ-9; 9.3% met the criteria for major depression based on PHQ-9 ≥ 10; and 19.7% based on PHQ-9 ≥ 15. Using the OAHMQ, 19.7% reported probable major depression and 44.5% clinically significant symptomatology. Conclusions: The measures were highly correlated overall. However, the estimated prevalence of depressive disorders varied substantially between the 2 instruments. These estimates were comparable to those previously reported for each instrument (i.e., higher rates with the OAHMQ). Therefore, differing estimates of depressive disorders reported in the literature using these instruments were largely attributable to the instruments themselves. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
104.
The brain must deal with a massive flow of sensory information without receiving any prior information. Therefore, when creating cognitive models, it is important to acquire as much information as possible from the data itself. Moreover, the brain has to deal with an unknown number of components (concepts) contained in a dataset without any prior knowledge. Most of the algorithms in use today are not able to effectively copy this strategy. We propose a novel approach based on neural modelling fields theory (NMF) to overcome this problem. The algorithm combines NMF and greedy Gaussian mixture models. The novelty lies in the combination of information criterion with the merging algorithm. The performance of the algorithm was compared with other well-known algorithms and tested both on artificial and real-world datasets.  相似文献   
105.
106.
PARALLEL-MACHINE SCHEDULING WITH FRACTIONAL OPERATOR REQUIREMENTS   总被引:1,自引:0,他引:1  
This paper discusses the fractional operator problem, which involves the production of many parts on several parallel machines. In this problem, operators can monitor more than one adjacent machine subject to the operator requirements of the parts being produced on those machines. Thus, the combination of parts being produced determines the number of operators required. We consider minimizing the average setup and holding costs subject to a constraint on the number of operators available. We describe planning- and control-level versions of the problem and give formulations that provide a basis for future work.  相似文献   
107.
30 high-speech-anxious and 30 low-speech-anxious Ss participated in an experiment to test the hypothesis that misattribution would reduce the anxiety of speech-anxious Ss. The present study crosscut misattribution vs no misattribution (control) and high vs low speech anxiety and assessed the impact on Ss' nervous behavior and subsequent speech making. The misattribution concerning bodily preparation for Ss' speech-making events was delivered verbally to 15 speech-anxious and 15 nonanxious Ss prior to their speeches. Results show that misattribution did not significantly affect the behavior of Ss making speeches. Implications for misattribution when personality traits are involved are discussed. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
108.
This study presents situational risk scenarios to predict the potential implications of predicted and perceived thermal configurations on the health and well-being of health care professionals in intensive care units (ICUs). Nine ICUs were selected, and thermal variables were collected; simultaneously, 128 health care professionals were interviewed to assess their perceptions, satisfaction, and health conditions related to their workplace environment. In scenarios with thermal comfort (either predicted or perceived), the risk of exposure to physical and psychological symptoms was reduced. This effect also extends to predictions and perceptions tending toward slightly cooler temperatures. In situations with a predicted mean vote below −1.5 and above 0.5, symptom complaints increased, even when the health care professionals perceived their environment as thermally comfortable, with the most extreme cases generating an increase of up to 27% in the baseline probability. Adjusting the workplace environment to be thermally comfortable can reduce symptom complaints.  相似文献   
109.
This paper proposes a saturated nonlinear PID regulator for industrial robot manipulators. Our controller considers the natural saturation problem given by the output of the control computer, the saturation phenomena of the internal PI velocity controller in the servo driver, and the actuator torque constraints of the robot manipulator. An approach based on the singular perturbations method is used to analyze the exponential stability of the closed-loop system. Experimental essays show the feasibility of the proposed controller. Furthermore, the theoretical results justify why the classical PID used in industrial robots preserves its exponential stability despite the saturation effects of the electronic control devices and the actuator torque constraints.  相似文献   
110.
The cover image, by Marco Rito‐Palomares et al., is based on the Perspective Monolithic chromatography: insights and practical perspectives, DOI: 10.1002/jctb.5040 .

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