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991.
Albano RD de Souza SB 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2001,17(4):941-947
This study aimed to assess the nutritional status of adolescents. A cross-sectional study was taken in a public high school in S?o Paulo, Brazil, with 92 students ages 11 to 17 years. The sample was performed using systematic statistical selection. Nutritional status of adolescents was assessed using body mass index (BMI), compared to WHO (1995) standards. Prevalence rates for "risk of overweight" and "overweight" were 27.9% and 4.6%, respectively, for boys, as compared to 10.2% and 16.3% for girls. Prevalence of "risk of overweight" and "overweight" was thus high for both sexes; the results were similar in comparison to other studies. In addition, the difference in nutritional status between genders was significant (p < 0.05). 相似文献
992.
Souza Cappi DR de Jesus JG Nichiata LY Takahashi RF 《Revista latino-americana de enfermagem》2001,9(1):66-72
The paper describes the experience of undergraduate nursing students in a Center of Testing and Counseling (CTA), that offers anti-HIV test. There were identified the facilities and the difficulties faced in the accomplishment of the counseling before and after-test, for five months, aiming to propose strategies to surmount them. 相似文献
993.
Cordova Rosa EV Simionatto EL de Souza Sierra MM Bertoli SL Radetski CM 《Environmental toxicology and chemistry / SETAC》2001,20(4):839-845
Brazilian textile mills import wastewater treatment technologies, performances of which are generally evaluated only on a physicochemical basis. Thus, a battery of bioassays was used to evaluate the performance of an ozonation system to treat textile effluents. Comparative toxicological profiles for bacteria (Vibrio fischeri), algae (Scenedesmus subspicatus), daphnia (Daphnia magna), fish (Poecilia reticulata), and plants (soybean--Glycine max, rice--Oryza sativa, and wheat--Triticum aestivum), as well as genotoxic effects (Vicia faba micronucleus assay), are presented for both raw and ozonated textile effluents. The relative sensitivity of bioassays (or end points) to textile effluents found in this study in decreasing order was plant enzymes > bacteria > algae daphnids approximately = plant biomass approximately = germination rate > fish. No significant genotoxic effect was found. We have concluded that ozonation was relatively effective in reducing toxicity of textile effluents. Bioassays used in this study proved to be sensitive and reliable tools for determining the toxicity of industrial effluents, and thus they can be used to evaluate emerging technology efficiency. 相似文献
994.
Knowledge of the physiological roles of the purinergic system and its influence on other neurotransmitter systems has greatly advanced. In this article, a purinergic model is proposed as an attempt to integrate several findings in schizophrenia. According to this hypothesis, a purinergic system dysfunction would mainly result in reduced adenosinergic activity. This model also addresses the systemic aspects of schizophrenia, based on peripheral roles of purines, such as modulation of the immune system. 相似文献
995.
Duarte MA Demarchi AC Giaxa MH Kuga MC Fraga SC de Souza LC 《Journal of endodontics》2000,26(7):389-390
The pH and calcium ion release of three root canal sealers--Sealapex, Sealer 26, and Apexit--were assessed at 24 and 48 hr, and at 7 and 30 days after spatulation. After manipulation, the sealers were placed in 1-cm-long tubes measuring 4 mm in diameter and immersed in a glass flask containing 10 ml of deionized water, which was hermetically sealed and stored at 37 degrees C. The tubes were removed at the scheduled times and the water in which they were immersed was tested for pH with a pHmeter and for released calcium by atomic absorption spectrophotometry. Starting 48 hr after immersion, Selapex produced an alklaine pH and released significantly higher calcium amounts compared with the other two sealers, with even more pronounced results after 30 days. On the basis of the results obtained, we conclude that Sealapex presented the highest calcium and hydroxyl release, especially after longer time intervals, whereas Sealer 26 showed highest release during the initial periods (i.e. during its setting time). Apexit presented the least satisfactory results. 相似文献
996.
The purpose of this article is to present a simple and easy method for in vitro analysis of root canal instrumentation that permits one to observe and measure the diameter of a root before and after instrumentation, using the teeth themselves as control. 相似文献
997.
Importance of nasal fiberoptic examination in the presence of a normal X-ray of the cavum 总被引:1,自引:0,他引:1
Souza BB Hennemann GV Anselmo-Lima WT 《International journal of pediatric otorhinolaryngology》2000,55(1):29-32
A total of 45 children aged 4-12 years were studied at the Rhinosinusology out-patient clinic of HCFMRP. The patients complained of marked nasal obstruction refractory to any clinical treatment, and a cavum X-ray showed no sign of airway obstruction. All children were submitted to nasal fiberoptic examination in order to determine the number of false-negative results. The examinations showed 12 cases of severe hypertrophy of adenoid vegetations (27%) and 19 cases of moderate hypertrophy (42%). Furthermore, we detected six cases of hypertrophy of the turbinate cauda (13.3%) and three cases of posterior septal deviation (6.6%). These data suggest the importance of the indication of this examination, which permits a tri-dimensional and dynamic evaluation of the cavum area. 相似文献
998.
Zhang QS Maddock DA Chen JP Heo S Chiu C Lai D Souza K Mehta S Wan YS 《International journal of oncology》2001,19(5):1057-1061
A previous study has shown that UV activates the PI3K/AKT cell survival pathway while inducing cell death in human skin in vivo and cultured human keratinocytes in vitro, and yet the upstream pathway leading to the activation of AKT has not been thoroughly investigated. In this study we found that UV-induced phosphorylation of p38 and AKT in a time-dependent manner. The phosphorylation of p38 started at 5 min post UV irradiation, peaked at about 30 min, and remained elevated up to 2 h. The phosphorylation of AKT started at 15 min post UV treatment, peaked at about 1 h, and remained elevated up to 2 h. We also found that H2O2 induced phosphorylation of p38 and AKT in a time- dependent manner. Pretreatment with NAC abolished UV-induced AKT phosphorylation, suggesting the involvement of reactive oxygen species in AKT activation. Interestingly, SB203085, a known p38 inhibitor, had partially inhibited UV-induced AKT phosphorylation. Further studies showed that cytokines such as TNF-alpha and IL-1beta induced AKT phosphorylation in a time-dependent manner. Pretreatment with SB203085 inhibited IL-1beta-induced p38 and AKT phosphorylation. Collectively, our data suggest that UV activation of PI 3-kinase/AKT pathway is initiated by ROS and prolonged by feedback activation of p38 induced by released cytokines in response to UV irradiation in cultured human keratinocytes. 相似文献
999.
1000.
Acute effects of leptin on glucose metabolism of in situ rat perfused livers and isolated hepatocytes 总被引:2,自引:0,他引:2
Ceddia RB Lopes G Souza HM Borba-Murad GR William WN Bazotte RB Curi R 《International journal of obesity (2005)》1999,23(11):1207-1212
OBJECTIVE: To investigate whether leptin interferes directly with glycogenolysis and gluconeogenesis in isolated rat hepatocytes and also in in situ rat perfused livers. ANIMALS: Male albino rats (200-250 g) were used in all experiments. MEASUREMENTS: D-glucose, L-lactate and pyruvate production. RESULTS: In the present study, no differences were found for the rates of glycolysis, as expressed by the areas under the curves, among control (24.2+5.0 mmol?g), leptin (32.0+4.5 mmol?g), glucagon (24.7+3.0 mmol?g), and the leptin + glucagon (23.8+3.4 mmol?g) groups. No difference was found for the rates of glycogenolysis between the control and the leptin perfused livers (15.2+3.9 and 15.0+3.2 mmol?g, respectively). In the presence of glucagon, the areas under the curves for the rate of glycogenolysis rose to 108.6+3.8 mmol?g. When leptin was combined with glucagon, the area under the curve for glycogenolysis was 43. 7+4.3 mmol?g. In fact, leptin caused a reduction of almost 60% (P<0. 001) in the rate of glucagon-stimulated glycogenolysis. Under basal conditions, the addition of leptin (100 ng?ml) to the incubation medium did not elicit any alteration in glucose production by isolated hepatocytes. However, in the presence of leptin, the production of glucose from glycerol (2 mM), L-lactate (2 mM). L-alanine (5 mM) and L-glutamine (5 mM) by the isolated hepatocytes was significantly reduced (30%, 30%, 23% and 25%, respectively). The rate of glucose production (glycogenolysis) by isolated hepatocytes was not different between the control and the leptin incubated groups (445.0+/-91.0 and 428.0+/-72.0 nmol?106 cells?h, respectively). CONCLUSION: We conclude that leptin per se does not directly affect either liver glycolysis or its glucose production, but a physiological leptin concentration is capable of acutely inducing a direct marked reduction on the rate of glucagon-stimulated glucose production in in situ rat perfused liver. Leptin is also capable of reducing glucose production from different gluconeogenic precursors in isolated hepatocytes. 相似文献