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排序方式: 共有9037条查询结果,搜索用时 15 毫秒
101.
102.
D Lerda M Biaggi Bistoni N Peralta S Ychari M Vazquez G Bosio 《Food and chemical toxicology》2005,43(5):691-698
Fumonisins B(1), B(2)yB(3) (FB(1), FB(2)yFB(3)), are a group of toxins produced by different mold species, Fusarium moniliforme and Fusarium proliferatum being the most important ones. Its compounds were tested in chromosome aberrations (CA), sister chromatid exchange (SCE), and micronucleus (MN) in human lymphocytes, and, in Allium cepa (onion), the chromosomal aberrations (CA) assay was used. Moreover, the presence of fumonisins and their producer moulds was determined in different food substrata in Cordoba city, Argentina. Cytogenetic studies using FB(1), FB(2) and FB(3) levels gave positive results for the higher concentrations (5 and 10mug/g) with FB(1). As regards the cytogenetic aspect of FB(1), we found an increase in the incidence of genetic damage measured by chromosomal aberrations, sister chromatid exchange, micronuclei and chromosomal aberrations in Allium cepa. These results indicate that human lymphocytes cells and plants cells (Allium cepa) have a very sensitive cellular response to the mycotoxin fumonisin B(1) as observed at the highest concentrations. 相似文献
103.
The role of associated injuries on outcome of blunt trauma patients sustaining pelvic fractures 总被引:7,自引:0,他引:7
Gustavo Parreira J Coimbra R Rasslan S Oliveira A Fregoneze M Mercadante M 《Injury》2000,31(9):677-682
In order to identify the prognostic factors and to evaluate the impact of associated injuries in the outcome of patients with pelvic fractures, a retrospective review of the medical records of patients admitted with a pelvic fracture during a 42-month period was carried out. Demographic data, the mechanism of injury, the physiologic status on admission, associated injuries, pelvic fracture classification, complications and mortality were analysed. One hundred and three patients were included in the study. Fifty-nine were male, and the mean age was 34. The mean Revised Trauma Score (RTS) and Injury Severity Score (ISS) were 7.1 and 20, respectively. Pedestrian vs vehicle (59%), was the most frequent mechanism of injury. Twenty patients died (19%) most frequently due to "shock". Complications developed in 37 patients (36%), pneumonia being the most frequent. Age greater than 40 years (p=0.02), "shock" upon admission (p=0.002), a Glasgow Coma Scale (GCS)<9, Head AIS>2 (p<0. 001), Chest AIS>2 (p=0.007), and abdominal AIS>2 (p=0.03) all correlated with increased mortality. No correlation between pelvic fracture classification or fracture stability with mortality was observed. The outcome of patients with pelvic fractures due to blunt trauma correlates with the severity of associated injuries and physiological derangement on admission rather than with characteristics of or the type of fracture. 相似文献
104.
Gustavo Adolfo Avila Montes Mercedes Martínez Catalina Sherman Eduardo Fernández Cerna 《Pan American journal of public health》2004,16(2):84-94
OBJECTIVE: To evaluate the effectiveness of a special course on environmental health and dengue, given to primary school students and intended to promote behavioral changes in the mothers of those students that would lead to the safe handling of water, adequate disposal of trash, and control of household breeding sites of Aedes aegypti, the mosquito vector for dengue. METHODS: In the period from April to November 2002 a community field trial was carried out that included four public schools in the city of Comayaguela, Honduras. Two of the schools formed the intervention group, and the two others made up the comparison or control group. The data collection activities before and after the intervention included knowledge tests for the schoolchildren and the teachers; surveys of the knowledge, attitudes, and practices of the students' mothers; entomological surveys (systematic checking in order to find water containers, to search for mosquito larvae) in the homes of the schoolchildren; in-depth interviews with the students' mothers; observation in the classrooms; and postintervention focus group with the teachers. RESULTS: During the intervention period the largest epidemic of classical dengue ever in the history of Tegucigalpa, the capital of Honduras, occurred. That event prompted the Secretariat of Health to undertake large-scale control activities. In the two intervention schools there was a significant increase in the students' knowledge of the following three variables: dengue caused by a virus, life cycle of the vector, and reduction of breeding sites, which is the most effective measure for controlling the vector (P < 0.0001 for all those increases in knowledge). There were also significant increases in the knowledge of the same variables among the teachers in the intervention schools: dengue caused by a virus (P = 0.03), life cycle of the vector (P = 0.01), and reduction of breeding sites (P = 0.004). Reducing the number of breeding sites as being the best measure for controlling Aedes aegypti was the knowledge variable that showed the greatest change among the mothers in the intervention group (P = 0.02). The values for two of the entomological indices (the House index and the Breteau index) were better in the intervention group than in the control group, but the difference was not statistically significant. However, there was a statistically significant difference in the Breteau index values between the two control group schools and the one intervention school where the education course was implemented more adequately than in the other intervention school. CONCLUSIONS: The application of educational interventions directed to schoolchildren, as a part of a comprehensive plan for controlling Aedes aegypti, is an effective way to raise the awareness of teachers and parents with respect to the problem of dengue, and it also helps in encouraging family members to be involved in reducing breeding sites in the home. In moving to control the dengue vector, this strategy should take into consideration the involvement not only of families but also of civic and public institutions in the community. Given our results, it appears that this approach of using a special course for schoolchildren can constitute a fundamental pillar in the strategy for integrated dengue control. 相似文献
105.
Patrick D. Worhunsky Gustavo A. Angarita Zu Wei Zhai David Matuskey Jean-Dominique Gallezot Robert T. Malison Richard E. Carson Marc N. Potenza 《Neuropsychopharmacology》2021,46(2):316
Stimulant-use disorders have been associated with lower availability of dopamine type-2 receptors (D2R) and greater availability of type-3 receptors (D3R). Links between D2R levels, cognitive performance, and suppression of the default mode network (DMN) during executive functioning have been observed in healthy and addicted populations; however, there is limited evidence regarding a potential role of elevated D3R in influencing cognitive control processes in groups with and without addictions. Sixteen individuals with cocaine-use disorder (CUD) and 16 healthy comparison (HC) participants completed [11C]-(+)-PHNO PET imaging of D2R and D3R availability and fMRI during a Stroop task of cognitive control. Independent component analysis was performed on fMRI data to assess DMN suppression during Stroop performance. In HC individuals, lower D2R-related binding in the dorsal putamen was associated with improved task performance and greater DMN suppression. By comparison, in individuals with CUD, greater D3R-related binding in the substantia nigra was associated with improved performance and greater DMN suppression. Exploratory moderated-mediation analyses indicated that DMN suppression was associated with Stroop performance indirectly through D2R in HC and D3R in CUD participants, and these indirect effects were different between groups. To our knowledge, this is the first evidence of a dissociative and potentially beneficial role of elevated D3R availability in executive functioning in cocaine-use disorder.Subject terms: Addiction, Cognitive control 相似文献
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107.
Hellen Silva Cintra Juliana Castro Dourado Pinezi Graziella Dias Pinheiro Machado Gustavo Moura de Carvalho Ana Terra Silva Carvalho Thalles Eduardo Dias dos Santos Ricardo Duarte Marciano Renata de Bastos Ascen?o Soares 《Disease markers》2013,35(6):701-710
The purpose of this study was to evaluate the association between ATM, TP53 and MDM2 polymorphisms in prostate cancer patients and morbidity after radiotherapy. The presence of ATM (rs1801516), TP53 (rs1042522, rs1800371, rs17878362, rs17883323, and rs35117667), and MDM2 (rs2279744) polymorphisms was assessed by direct sequencing of PCR fragments from 48 patients with histologically proven prostate adenocarcinoma and treated with external beam radiation. The side effects were classified according to the Radiation Therapy Oncology Group (RTOG) score. The results showed no association between clinical characteristics and the development of radiation toxicities (P > 0.05). The C>T transition in the position 16273 (intron 3) of TP53 (rs35117667) was significantly associated with the risk of acute skin toxicity (OR: 0.0072, 95% CI 0.0002–0.227, P = 0.003). The intronic TP53 polymorphism at position 16250 (rs17883323) was associated with chronic urinary toxicity (OR: 0.071, 95%CI 0.006–0.784, P = 0.032). No significant associations were found for the remaining polymorphisms (P > 0.05). The results show that clinical characteristics were not determinant on the developing of radiation sensitivity in prostate cancer patients, and intronic TP53 polymorphisms would be associated with increased acute and chronic radiation toxicities. These observations corroborate the importance of investigating the genetic profile to predict adverse side effects in patients undergoing radiotherapy. 相似文献
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