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41.
Raquel Alves dos Santos Teresinha Rosa Cabral Isabel Rosa Cabral Lusania Maria Greggi Antunes Cristiane Pontes Andrade Plínio Cerqueira dos Santos Cardoso Marcelo de Oliveira Bahia Claudia Pessoa José Luis Martins do Nascimento Rommel Rodríguez Burbano Catarina Satie Takahashi 《Biocell》2008,32(2):195-200
Physalis angulata L (Solanaceae) is a medicinal plant from North of Brazil, whose different extracts and infusions are commonly used in the popular medicine for the treatment of malaria, asthma, hepatitis, dermatitis and rheumatism. However, the genotoxic effects of P. angulata on human cells is not well known. The main purpose of the present study was to evaluate the in vitro genotoxic effects of aqueous extract of P. angulata using the comet assay and the micronucleus assay in human lymphocytes provided from 6 healthy donors. Treatments with P. angulata extracts were performed in vitro in order to access the extent of DNA damage. The comet assay has shown that treatments with P. angulata at 0.5, 1.0, 2.0, 3.0 and 6.0 microg/mL in culture medium were genotoxic. Lymphocytes treated with P. angulata at the concentrations of 3.0 and 6.0 microg/mL in culture medium showed a statistically significant increase in the frequency of micronucleus (p<0.05), however, the cytokinesis blocked proliferation index (CBPI) was not decreased after P. angulata treatment. In conclusion, the present work demonstrated the genotoxic effects of P. angulata extract on human lymphocytes in vitro. 相似文献
42.
People have knowledge about relationships (i.e., relational schemas) that is based on their experiences. Because most people have experience with complementary behavior (interaction partners behaving similarly in terms of affiliation but oppositely in terms of control), they expect complementary behavior in their relationships. Like other beliefs about relationships, expectations of complementarity affect self-construal. The authors provide evidence for complementary self-construal; people assimilate to relevant relationship partners on the affiliation dimension and contrast on the control dimension. Consistent with the proposed role of relationship knowledge in these effects, complementary self-construal was moderated by the familiarity of the target, whether people focused on their relationship with or the appearance of the target, and whether the context was relevant for the interpersonal dimension. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
44.
Camelia Betianu Florentina A Caliman Maria Gavrilescu Igor Cretescu Corneliu Cojocaru Ioannis Poulios 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(11):1454-1465
BACKGROUND: Heterogeneous photocatalysis is influenced by a number of parameters involving synergistic effects; hence, an experimental strategy design that considers interactions between the main variables is needed. The response surface methodology was applied for the investigation of photodegradation of 20 mg L?1 Orange II in aqueous solutions and for optimization of color removal efficiency. Preliminary studies were performed to identify the parameters to be selected for optimization. RESULTS: The input variables considered for experimental design were: solution initial pH, oxidizing agent (H2O2) initial concentration and UV‐A irradiation time. The multivariate experimental design allowed the development of a quadratic response surface model to be used for the prediction of color removal efficiency over the full range of the experimental region. Under the optimum conditions established in the region of experimentation (pH = 6.9, [H2O2]0 = 183 mg L?1 and t = 32 min), a 100% color removal efficiency was obtained in experiments. CONCLUSIONS: It was found that the variables considered have important effects on color removal efficiency. The results demonstrate that the use of experimental design strategy is indispensable for successful investigation and adequate modeling of the process because the interdependence of the reaction parameters cannot be neglected. Copyright © 2008 Society of Chemical Industry 相似文献
45.
Gerardo Gabriel Acosta Miguel Angel Mayosky José Maria Catalfo 《Applied Intelligence》1994,4(1):53-66
This article proposes a scheme for the on-line adjustment of three mode controller settings based on experimental measurements of closed-loop performance. It uses a recently developed heuristic tuning procedure to identify estimated process parameters. This method may give rise to conflicting estimates. Fuzzy Set theory is applied to manage the situation in terms of a fuzzy conjunction to combine the various estimates. PID control was chosen because of its wide use in the industrial environment due to driving simplicity and robustness. The article shows design, development, and computer simulation aspects. 相似文献
46.
Heloisa Martins Shih Mitchell M Tseng 《International Journal of Project Management》1996,14(6):373-378
In this paper the application of workflow technology to monitor, control and coordinate business processes and projects is proposed. The conceptual characteristics of processes and projects as well as their management needs in the functions of planning, execution, monitoring and control are compared. The general design of the proposed system is then developed, with an application example. The proposed monitoring and control system provides proactive tracking of the flow of work and information, and of the utilization and commitment of resources. The design supports hierarchical management of the project and/or business process, allowing concerned persons to visualize and to utilize it in different levels of abstraction, as necessary. The application of workflow technology also provides additional benefits in facilitating communication, documentation and re-utilization. 相似文献
47.
J. R. Prez-Correa F. R. Sepúlveda M. A. Duarte 《International Journal of Adaptive Control and Signal Processing》1995,9(2):183-197
This paper presents experimental results obtained in temperature adaptive control of a heating vessel. A non-linear model of the process showed that the feed flow rate causes severe variations in time constant and process gain. An extended horizon self-tuning controller and two different model reference adaptive controllers were tested. The influence of design parameters on control performance for each algorithm was assessed. The control system was disturbed with load and setpoint changes. 相似文献
48.
RM Hendry CV Hanson V Bongertz M Morgado A Duarte J Casseb L Brigido E Sabino R Diaz B Galv?o-Castro 《Canadian Metallurgical Quarterly》1996,91(3):347-348
The influence of noncompetitive (MK-801), competitive (AP-7) and the antagonist of polyamines site of NMDA receptor (arcaine) on the central activity of angiotensin II (A II) was studied. The open field test, conditioning of active avoidance responses (CARs) and passive avoidance situation was used to investigate learning and memory in rats. All used antagonists decreased beneficial action of A II on these processes. 相似文献
49.
The lipid composition of blubber, brain, muscle and heart from a Mediterranean monk sealMonachus monachus (an endangered species) were examined to allow comparisons with more common species of seals. Only neutral lipids (mainly
triacylglycerols) were detectable in the blubber lipids, whereas polar lipids predominated in the heart and in the brain.
Neutral and polar lipids comprised almost equal proportions in both liver and muscle. Choline glycerophospholipids (CGP) were
the major polar lipids, followed by ethanolamine glycerophospholipids (EGP) in the liver, heart and muscle. Cerebrosides accounted
for 28.8% of the brain lipids. All lipid classes of the liver contained high levels (31–47%) of polyunsaturated fatty acids
(PUFA), with the exception of phosphatidylserine. The total proportion of n−6 PUFA exceeded that of n−3 PUFA in all lipid
classes of the liver, due mainly to the high levels of 20∶4n−6. The highest level of 20∶4n−6 occurred in phosphatidylinositol,
where it comprised 32.4% of the total fatty acids. The CGP and EGP of the brain contained lower levels of PUFA than those
of the liver, muscle and heart. Alkenyl ethers accounted for 35.8% of the total long-chain moieties in brain EGP. The fatty
acid composition of blubber triacylglycerols differed from those of the lipid classes from other tissues in that it had a
very low ratio of n−6 to n−3 PUFA (0.3) as a result of a lower content of 20∶4n−6. 相似文献
50.
T Paiva A Farinha A Martins A Batista C Guilleminault 《Canadian Metallurgical Quarterly》1997,157(15):1701-1705
BACKGROUND: Headaches and sleep problems are common complaints in the daily practice of the general practitioner. Since the relationship between headaches and sleep complaints is complex, clear models of interaction are needed for adequate diagnosis and treatment. METHODS: All subjects, successively seen in a headache clinic during a defined period, were subdivided based on the time of onset of cephalalgia. Subjects who reported onset of headache on a long-term basis, during the nocturnal or early morning (before final awakening) period, were systematically studied by a headache clinic and a sleep disorders center. This subgroup represented 17% of the total headache group. RESULTS: Although the results of the headache clinic study did not differentiate this subgroup from the other patients, the sleep disorders center's interviews and questionnaires demonstrated a significant impact of the sleep disorders on headache and daytime function. Nocturnal monitoring during sleep identified specific sleep disorders in 55% of the subjects with onset of headache during the nocturnal sleep period. Follow-up after treatment of the sleep disorder showed that all subjects with an identifiable sleep disorder reported either an improvement or absence of their headache. The subjects identified with periodic limb movement syndrome were mostly those who reported only an improvement in their sleep and still needed treatment for their headaches. The question of the interaction and association of sleep-related headache and periodic limb movement syndrome is unresolved. CONCLUSION: Headaches occurring during the night or early morning are often related to a sleep disturbance. 相似文献