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A simulation study of the Tunisian Gamma Irradiation Facility for sterile insects release programs has been realized using the GEANT4 Monte Carlo code of CERN. The dose was calculated and measured for high and low dose values inside the irradiation cell. The calculated high dose was in good agreement with measurements. However, a discrepancy between calculated and measured values occurs at dose levels commonly used for sterilization of insects. We argue that this discrepancy is due to the transit dose absorbed during displacement of targets from their initial position towards their irradiation position and displacement of radiation source pencils from storage towards their irradiation position. The discrepancy is corrected by taking into account the transit dose.  相似文献   
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Autoimmune thyroid diseases (AITDs), which include Hashimoto thyroiditis (HT), Graves' disease (GD) and primary idiopathic myxoedema (PIM), are recognized as multifactorial diseases. In this study, we have examined single and haplotypic genetic variation across the major histocompatibility complex (MHC) in a Tunisian isolate with a high prevalence of AITDs (62 patients: 32 with GD, 9 with HT and 21 with PIM). Genotyping was performed for HLA class I and II alleles as well as polymorphisms within tumor necrosis factor (TNF), lymphotoxin alpha (TLalpha) and heat shock protein (HSP70-02 and HSP70-hom) genes. Our results showed association of HLA-A2-B50-TNF 2 haplotype with AITDs (p = 0.045). Linkage analysis using Simwalk2 program has shown significant result with TNF -308 gene polymorphism (p = 0.03). The FBAT has given evidence for genetic association with TNF -308 and HLA-DR gene polymorphisms. TNF 2 allele was associated with GD (p = 0.0011), whereas TNF 1, HLA-DR11 and DR12 (p = 0.0039, p = 0.00089 and p = 0.0056, respectively) were rather implicated in HT pathogenesis. Results found by TDT-STDT have confirmed the involvement of the TNF -308 gene polymorphism in AITD pathogenesis (p < 10(-9)).  相似文献   
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IPT-AFM is a proprietary animal component free medium that was developed for rabies virus (strain LP 2061) production in Vero cells. In the present work, we demonstrated the versatility of this medium and its ability to sustain the growth of other cell lines and different virus strains. Here, three models were presented: Vero cells/rabies virus (strain LP 2061), MRC-5 cells/measles virus (strain AIK-C) and BHK-21 cells/rabies virus (strain PV-BHK21). The cell lines were first adapted to grow in IPT-AFM, by progressive reduction of the amount of serum in the culture medium. After their adaptation, BHK-21 cells grew in suspension by forming clumps, whereas MRC-5 cells remained adherent. Then, kinetics of cell growth were studied in agitated cultures for both cell lines. In addition, kinetics of virus replication were investigated.  相似文献   
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ObjectivesThe purpose of this work was to evaluate the prevalence of malocclusions and orthodontic treatment need among schoolchildren in Casablanca, Morocco.Materials and methodsA sample of 1000 children aged between 8 and 12 years, with no history of orthodontic treatment, was chosen at random in state schools in different administrative areas of the city of Casablanca. Data was registered using the method of Bjork et al. (1964). Orthodontic treatment need was assessed with the index used by the Swedish National Board of Health (SweNBH).ResultsWe found Angle Class I malocclusions in 61.4%, Class II in 24%, Class III in 10% and an indeterminate molar class with one or more missing molars in 4.6% of the children. Overjet was 1–4 mm in 63.8%, 4–6 mm in 17.2% and >6 mm in 10%. Bite was normal in 65.4%, 23.6% presented an overbite greater than 4 mm, 1.7% an anterior open bite ≤3 mm, 1.2% an anterior open bite >3 mm and 0.2% a bilateral open bite. Half of the sample presented anterior crowding, while only 2.5% presented posterior crowding. In all, 84.2% of the subjects needed some orthodontic treatment, and 15.8% needed no treatment. No statistically significant difference was found between sex or age and orthodontic treatment need (P>0.05).ConclusionsThis study found a strong need for orthodontic treatment, confirming the utility of implementing a programme of bucco-dental prevention and screening for malocclusion.  相似文献   
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We address in the present paper a medical monitoring system designed as a multi-agent based approach. Our system includes mainly numerous agents that act as correlated multi-agent sub-systems at the three layers of the whole monitoring infrastructure, to avoid non informative alarms and send effective alarms at time. The intelligence in the proposed monitoring system is provided by the use of time series technology. In fact, the capability of continuous learning of time series from the physiological variables allows the design of a system that monitors patients in real-time. Such system is a contrast to the classical threshold-based monitoring system actually present in the Intensive Care Units (ICUs) which causes a huge number of irrelevant alarms.  相似文献   
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Medial prefrontal circuits have been reported to undergo a major reorganization over time and gradually take a more important role for remote emotional memories such as contextual fear memory or food aversion memory. The medial prefrontal cortex, and specifically its ventral subregion, the infralimbic cortex (IL), was also reported to be critical for recent memory extinction of contextual fear conditioning and conditioned odor aversion. However, its exact role in the extinction of remotely acquired information is still not clear. Using postretrieval blockade of protein synthesis or inactivation of the IL, we showed that the IL is similarly required for extinction consolidation of recent and remote fear memory. However, in odor aversion memory, the IL was only involved in extinction consolidation of recent, but not remote, memory. In contrast, only remote retrieval of aversion memory induced c-Fos activation in the IL and preretrieval inactivation of the IL with lidocaine impaired subsequent extinction of remote but not recent memory, indicating IL is necessary for extinction learning of remote aversion memory. In contrast to the effects in odor aversion, our data show that the involvement of the IL in the consolidation of fear extinction does not depend on the memory age. More importantly, our data indicate that the IL is implicated in the extinction of fear and nonfear-based associations and suggest dissociation in the engagement of the IL in the learning and consolidation of food aversion extinction over time.  相似文献   
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