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81.
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   
82.
Intelligent multisensor surveillance systems consist of several types of sensors, which are installed on fixed and mobile devices. These components provide a huge quantity of information that has to be contrasted, correlated and integrated in order to recognize and react on special situations. These systems work in highly dynamic environments, with severe security and robustness requirements. All these characteristics imply the need for distributed solutions. In these solutions, scattered components can decide and act with some degree of autonomy (for instance, if they become isolated), or cooperate and coordinate for a complete tracking of special situations. In order to cope with these requirements and to better structure the solution, we have decided to design surveillance system control as a multiagent system. This is done by applying an agent-orientated methodology, which is assessed with concrete scenarios.  相似文献   
83.
The chip-thickness models, used to assess the performance of grinding processes, play a major role in predicting the surface quality. In the present paper, an attempt has been made to develop a new chip-thickness model for the performance assessment of silicon carbide grinding by incorporating the modulus of elasticities of the grinding wheel and the workpiece in the existing basic chip-thickness model to account for elastic deformation. The new model has been validated by conducting experiments, taking the surface roughness as a parameter of evaluation .  相似文献   
84.
Assessed the escalations in substance use over 3 yrs among 246 adolescent children of alcoholics (COAs) and 208 controls (aged 10.5–15.5 yrs). Older COAs showed the steepest escalations in drug use. Younger COAs whose fathers had continuing alcohol-related consequences showed the greatest escalations in alcohol use. Ss' beliefs about drinking restraint were related to their alcohol and drug use. Those whose alcoholic fathers had no continuing alcohol-related consequences showed the strongest relations between substance use and self-control reasons for limiting drinking, perceived risk for future drug problems, and seeing the negative effects of alcohol on someone else. These adolescents may be deterred from substance use escalations because of particular parental characteristics (e.g., mild forms of paternal alcoholism) or because of their beliefs about substance use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
Response of adults of the West Indian sugarcane weevil,Metamasius hemipterus sericeus, to various semiochemical treatments and physical trap designs was studied in southern Florida in field-grown banana and Canary Island date palms. Ethyl acetate released alone at 860–1007 mg/day was as effective for the capture ofM. h. sericeus as a combination of ethyl acetate (844–919 mg/day), ethyl propionate (348–362 mg/day), and ethyl butyrate (117–137 mg/day) and in one trial was more effective than fermenting sugarcane (250 g), ethyl propionate alone (353–384 mg/day), ethyl butyrate alone (123–174 mg/day), or no treatment. Ethyl acetate released alone at 675–683 mg/day was as attractive as 250 g of fermenting sugarcane or the racemic blend of the male-produced aggregation pheromones [(±)-5-methyl-nonan-4-ol and (±)-2-methyl-heptan-4-ol (8:1 ratio) “metalure”] at 3 mg/day. Weevil counts increased with binary combinations of ethyl acetate, sugarcane, and/or metalure over these treatments alone and the ternary combination was two to three times more effective than any of the binary treatments. Attraction to ethyl acetate released alone at 777 mg/day with metalure was greater than to the hydrolysis products of ethyl acetate (ethanol and/or acetic acid each released at about 6–8 mg/day) with metalure. Weevil counts from traps baited with 250 g of sugarcane and metalure increased with increasing dose of ethyl acetate to about 400 mg/day and then appeared to plateau. Ethyl acetate (about 700 mg/day) and metalure increased weevil counts in traps with increasing amounts of sugarcane (0–2 kg). Molasses (45 g) + water (158 ml) substitutes for sugarcane were about as effective for capturingM. h. sericeus as 250 g of fermenting sugarcane [all treatments with ethyl acetate (847 mg/day) and metalure]. Early experiments used a lethal pitfall trap. We demonstrated that several alternative trap designs were more effective than the lethal pitfall trap for capturing weevils. Color and height (on ground vs. 1 m on pole) did not affect trap efficacy when baited with the ternary combination of ethyl acetate (672–825 mg/day), sugarcane (250 g), and metalure.  相似文献   
86.
To acquire maximum information on the geometrical errors of industrially made surfaces at a minimum cost, a method for estimating conditional probabilities of a random signal (Bayesian prediction) is applied to three-dimensional metrology. First, a surface is interpolated between data acquired on a coordinate measuring machine (CMM). Then, for a given probability, limit surfaces are computed that bind a region of space containing the known data and the most probable interpolation of the missing data of the surface. These bounds can be treated as the surface; their points can be considered as if they were actual CMM data when fitting a tolerance zone or a datum feature to the data. For Bayesian prediction, the basic hypotheses on the signal are stationarity, ergodicity, and gaussian density. Deviations from these hypotheses and their consequences on the prediction are taken into account and corrections are proposed.  相似文献   
87.
88.
To assess the effects of diabetes mellitus on renal osteodystrophy, we examined the database of 256 patients (45% on hemodialysis and 55% on peritoneal dialysis) who were prospectively studied in three Toronto dialysis centers between October of 1987 and 1989. All patients had serial documentation of their clinical, laboratory and risk parameters of bone disease, and completed a series of investigations that included the deferoxamine test, measurement of intact 1-84 PTH levels, and an iliac crest bone biopsy. Twenty-five percent of these patients were diabetic. When compared to non-diabetic patients, they were on dialysis for a shorter duration (2.4 +/- 0.3 vs. 4.7 +/- 0.3 years; P < 0.0002), used calcium carbonate as the only phosphate binder more frequently (40 vs. 25%; P < 0.007), and had lower parathyroid hormone levels (12 +/- 1.4 vs. 24 +/- 2.3 pmol/liter; P < 0.002). High-turnover bone disorders (that is, osteitis fibrosa and mixed disorder) were distinctly uncommon (8 vs. 33%; P < 0.01 by Fisher's exact test), while the mild (19 vs. 9%; P = NS) and the aplastic disorders (with mean stainable bone surface aluminum of 6.5 +/- 0.7%) (46 vs. 31%; P = NS) tended to be more common in diabetic patients. The prevalence of aluminum bone disease was the same in both groups (27%). Diabetic patients ingested a smaller cumulative dose of aluminum gels (3.7 +/- 0.6 vs. 9.3 +/- 1.1 kg; P < 0.005), yet had a higher rate of aluminium accumulation on bone surfaces than non-diabetic patients (1.5 +/- 0.19 vs. 0.96 +/- 0.10% per month on dialysis; P < 0.015).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
89.
The architects and builders in the past lacked our knowledge concerning fluid dynamics, but they exhibited a deep rooted ability to observe and reflect - thus, different cultures have developed by trial and error. The authors have produced a stimulating analysis which couples the science of fluid dynamics and a sensitive understanding of past cultures. The paper is recommended reading.  相似文献   
90.
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   
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