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31.
This single case study investigated the effects of instructional variables on the initial acquisition, generalisation, and discriminative components of a requesting response in respect of two toothbrushing items. In Experiment 1, the effects of several teaching strategies (receptive language training, natural context training, and quick transfer training) on the acquisition of a requesting response were assessed. The quick transfer training method produced a requesting response with respect to both items. Requesting behaviour also generalised to a novel stimulus condition. In Experiment 2, quick transfer discrimination training resulted in the acquisition of a discriminated requesting response. Implications for assessment and training of spontaneous requesting skills are presented.  相似文献   
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OBJECTIVES: This study investigated the relationship between traffic air pollution and asthma, using a case-control design applied to routinely collected data. METHODS: Subjects resident in Turin during the period 1997-1999 and admitted for asthma were defined as cases; patients admitted for causes other than respiratory diseases or heart diseases were defined as controls. Nitrogen dioxide and total suspended particulate were considered as indicators of traffic air pollution. Statistical analysis were performed, separately for young (0-14 years), adult (15-64 years) and elderly (>64 years) patients, with a logistic regression model; results are expressed as percentage of risk modification for a 10 g/m(3) increase in exposure to pollutants. RESULTS: The risk of emergency admissions for asthma rose significantly with increased exposure to nitrogen dioxide [2.4%, 95% Confidence Interval: 0.5%; 4.3%], and total suspended particulate [2.3%, 95% Confidence Interval: 1.1%-3.6%]. The significant association was evident, in particular, among young and elderly patients for both pollutants. CONCLUSION: Using a case-control design both easy to use and manage, the study confirms the significant association between hospital emergency admissions for asthma and exposure to nitrogen dioxide and total suspended particulate pollutants.  相似文献   
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Ruthenium compounds have gained large interest for their potential application as chemotherapeutic agents, and in particular the complexes of the type (X)[trans-RuCl4(dmso-S)L] (X = HL or Na, NAMI-A or NAMI, respectively, for L = imidazole) are under investigation for their antimetastatic properties. The NAMI(-A)-like compounds are prodrugs that hydrolyze in vivo, and the investigation of their hydrolytic properties is therefore important for determining the nature of the potential active species. The NAMI-A-type Ru(III) complex 1, (Hdmtp)[trans-RuCl4(dmso-S)(dmtp)] (dmtp is 5,7-dimethyl[1,2,4]triazolo[1,5-a]pyrimidine), and the corresponding sodium analogue 2, (Na)[trans-RuCl4(dmso-S)(dmtp)], were synthesized. The hydrolyses of 1 and 2 in water as well as in buffered solutions were studied, and the first hydrolysis product, [mer-RuCl3(H2O)(dmso-S)(dmtp)].H2O (3), was isolated and characterized. The molecular structures of 1 and 3 were determined by single-crystal X-ray diffraction analyses and prove the importance of the hydrogen-bonding properties of dmtp to stabilize hydrolysis products. In vitro 1 (a) is not cytotoxic on tumor cells, following challenges from 1 to 72 h and concentrations up to 100 microM, (b) inhibits matrigel invasion at 0.1 mM and MMP-9 activity with an IC50 of about 1 mM, and (c) is devoid of pronounced effects on cell distribution among cell cycle phases. In vivo compound 1, similar to NAMI-A, significantly inhibits metastasis growth in mice bearing advanced MCa mammary carcinoma tumors. In the lungs, 1 is significantly less concentrated than NAMI-A, whereas no differences between these two compounds were found in other organs such as tumor, liver, and kidney. However, 1 caused edema and necrotic areas on liver parenchyma that are more pronounced than those caused by NAMI-A. Conversely, glomerular and tubular changes on kidney are less extensive than with NAMI-A. In conclusion, 1 confirms the excellent antimetastatic properties of this class of NAMI-A-type compounds and qualifies as an interesting alternative to NAMI-A for treating human cancers.  相似文献   
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Alcoholic polyneuropathy: a clinical and epidemiological study   总被引:1,自引:0,他引:1  
In the present study, we investigated the frequency of polyneuropathy in a sample of 296 alcoholics who were admitted to the 'S. Maugeri' Medical Centre for detoxification from October 1997 to November 1999. Results revealed a high frequency of polyneuropathy in the sample under study. The disorder was often clinically asymptomatic and demonstrable only on electroneurographic investigation. Significant correlations were found between polyneuropathy, the duration of alcoholism, the type of alcoholic beverage consumed (wine) and the presence of liver disease and macrocytosis.  相似文献   
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Early onset of absence seizures (<3 years) is rare and usually associated with a poor cognitive prognosis. Familial cases have not been reported to date. We observed a family in which two out of three sibs showed early-onset absences and mild mental retardation. Linkage to the ECA1 locus, where one clinical subtype of CAE is mapped, was excluded by haplotype analysis. Direct sequencing of the candidate genes CLCN2 ,GABRG2 and CHRNA4 showed no mutations. We suggest the possibility of a specific epileptic syndrome with a putative AR inheritance. Further report of affected patients might allow a better classification.  相似文献   
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Currently, there is an intense debate on the potential use of nonsteroidal anti-inflammatory drugs (NSAIDs) in Alzheimer's disease (AD). NSAIDs are among the most widely prescribed drugs for the treatment of pain, fever, and inflammation. Their effects are largely attributed to the inhibition of the enzymatic activity of cyclooxygenase (COX)-1 and -2. The apparent activity of this class of drugs stems from one critical pathological process underlying AD and other neurodegenerative disorders, i.e., the presence of chronic neuroinflammation. In fact, prolonged use of NSAIDs is associated with reduced risk of AD. Besides COX inhibition, additional mechanisms could contribute to the potential activity of NSAIDs in AD. For example, several studies show that only a few selected NSAIDs also affect β-amyloid (Aβ) deposition and metabolism. Among the Aβ-effective NSAIDs, flurbiprofen raised particular interest because of its multiple actions on key AD hallmarks. Studies in cell lines and animal models have shown that flurbiprofen racemate, its R-enantiomer and its nitric oxide (NO)-releasing derivatives, HCT 1026 and NCX 2216, are effective on AD amyloid pathology. Moreover, HCT 1026 and NCX 2216 differentially influence the cellular component of neuroinflammation (i.e., microglia activation) in some experimental settings, i.e., HCT 1026 inhibits the activation of microglia, while NCX 2216 can either enhance or inhibit microglial activation, depending upon the experimental conditions. It is still unclear which effects on microglia will prove most beneficial. Ultimately, clinical studies in AD patients will provide the best information as to whether selected NSAIDs will improve this devastating disease.  相似文献   
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