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51.
The excitatory conditioning model of contextual sensitisation proposes that the progressive emergence of the locomotion-activating effect of cocaine (or any other stimulant drug) characterising that phenomenon is due to a growing conditioned response (the test context cues) that mimics the unchanging unconditioned response (the drug effect). The present study aimed at verifying whether the relationship between the amplitude of sensitisation and the size of the conditioned response was positive, a direct implication of that view. Sensitisation to the locomotion-activating effect of cocaine (10 mg/kg, s.c.) was firstly generated over 10 daily sessions in 25 mice (strain C57Bl/6J), another lot of 25 mice receiving the same dose of cocaine outside of the testing context. Conditioned locomotion was assessed 24 h later. No significant linear correlations were found between the magnitude of the conditioned response and the magnitude of the sensitised response (delta scores), the rate of sensitisation (individual regression coefficients) or the magnitude of the initial unconditioned response to cocaine (scores in the first session of sensitisation treatment). Accordingly, there was no significant correlation between the magnitude of the initial unconditioned response and the magnitude of the sensitised response or that of the initial unconditioned response. Therefore, the conditioned response is neither necessary nor sufficient for the development of context-dependent sensitisation of the locomotion-activating effect of cocaine, a conclusion that refutes the excitatory conditioning model of that chronic effect.  相似文献   
52.
The 677cytosine mutation identified in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene has been frequently associated with an elevated plasma homocysteine concentration. The aim of the present study was to determine the impact of this MTHFR common mutation on plasma and erythrocyte folate (RCF) and plasma total homocysteine (tHcy) concentrations in healthy French adults. A cohort of 291 subjects living in the Paris area and participating in the Supplementation en Vitamines et Mineraux Antioxydants (SU.VI.MAX) study were analysed to assess the impact of MTHFR polymorphism 677C-->T on folate status and plasma tHcy concentration. The frequency of the mutant homozygote for 677C-->T polymorphism (677TT genotype) in the present cohort was 16.8%. There were significant differences in plasma tHcy between 677CC, 677CT and 677TT genotype groups. The RCF concentrations were significantly different between each genotype, the lowest levels being associated with the 677TT genotype. When segregated by gender, no differences in tHcy between homozygous 677TT, heterozygous 677CT and wild-type 677CC genotype groups in women were observed. The fasting tHcy in women was unrelated to the 677C-->T mutation. However, tHcy was significantly increased in men with the homozygous 677TT genotype. We also analysed the possible implication of a second new MTHFR polymorphism (1298A-->C) in subjects with mild hyperhomocysteinaemia (4th quartile of homocysteinaemia; tHcy >11.1 micromol/l). The polymorphism 1298A-->C did not have a notable effect on tHcy or on the RCF levels. Our observations confirm a relatively high frequency of the 677TT genotype in the French population. Women with this genotype did not show the same increase in tHcy observed in men. In the present study dietary folate intake was not measured. Thus, the interaction of dietary folate with the MTHFR genotype in the French population needs further study.  相似文献   
53.
A retrospective review is presented of 1353 consecutivepatients with histopathologically confirmed invasive breast carcinoma treatedradically with curative intent during the decade 1980–89.None had received adjuvant systemic therapy with hormonesor prolonged chemotherapy. The distribution of lymph-node negative(N–) and lymph-node positive (N+) patients was 75%and 25%, respectively.The treatment and outcome were analysed as regardsconventional prognostic parameters, in particular considering the axillarylymph-node status and the responsible hospital category (GeneralMunicipal Hospitals (MH)) versus Comprehensive Cancer Center (CC)).The most striking difference was detected as regardsthe number of examined lymph nodes. The mediannumber of nodes described at the MH was7, as compared to 14 at the CC(p < 0.001). In patients with pT1 tumoursthe highest rate of lymph-node positivity was observedwhen 10 or more axillary nodes were removed.Adjuvant radiotherapy reduced the loco-regional recurrence rate inthe N– patients, whereas only the regional recurrenceswere reduced among the N+ patients. The five-and 10-year tumor-related survival rates were 86% and76%, respectively, with no difference between the MHand the CC.As life-prolonging adjuvant hormone therapy and chemotherapy isnow available for patients with axillary lymph nodemetastases, it is important that patients with breastcancer are operated adequately with the aim toremove at least 10 axillary lymph nodes. Athorough examination of the axillary content should beperformed by the pathologist, and the number ofresected lymph nodes and metastases should be reported.The establishment of nation-wide standard criteria for themanagement of breast cancer is recommended.  相似文献   
54.
OBJECTIVE: To investigate the relationship between overweight and obesity, and mental health problems in Australian 4- to 5-year-old children. METHODS: The study used data from wave 1 (2004) of the Longitudinal Study of Australian Children (LSAC). The participants were 4983 4- to 5-year-old children (2537 boys and 2446 girls) with a mean age of 56.9 months (standard deviation 2.6 months; range 51-67 months). Children were classified as nonoverweight, overweight, and obese on the basis of International Obesity Task Force definitions. Mental health problems were assessed by the Strengths and Difficulties Questionnaire (SDQ) completed by parents and teachers. RESULTS: Although obese 4- to 5-year-old boys had more mental health problems than nonoverweight boys, differences between the groups were small and substantially reduced when analyses controlled for children's sociodemographic characteristics. Parents reported that overweight/obese girls had more peer problems, whereas teachers reported they had more conduct problems. Children in all weight groups had mean scores within the normal range of scores on all the SDQ subscales. CONCLUSIONS: Differences in rates of mental health problems experienced by young children of different weight status appear relatively small. Higher rates of mental health problems experienced by more obese boys may reflect differences in their sociodemographic characteristics rather than their weight status per se. Policies that reduce the number of young children living in poverty or experiencing other adverse social circumstances have the potential to reduce rates of mental health problems experienced by older children with overweight/obesity.  相似文献   
55.
Acetaldehyde, the first product of ethanol metabolism, has been suggested to play a major role in many behavioral effects of ethanol. However, very few studies have directly tested the behavioral effects of the acute administration of acetaldehyde. In particular, the role of this metabolite in ethanol-induced anxiolytic effects has never been extensively tested. The aim of the present study was to characterize the anxiolytic effects of acetaldehyde in two strains of mice, C57BL/6J and CD1 mice with the elevated plus-maze procedure. The results show that acute injections of ethanol (1–2 g/kg) induced significant dose-dependent anxiolytic effects in both strains of mice. In contrast, acetaldehyde failed to produce any anxiolytic effect, although it induced a significant hypolocomotor effect at the highest doses. In an independent experiment, cyanamide, an aldehyde dehydrogenase inhibitor, prevented the locomotor stimulant effects of ethanol, although it failed to alter its anxiolytic effects. Together, the results of the present study indicate that acetaldehyde is not involved in ethanol-induced anxiolytic effects, although it may be involved in its sedative/hypolocomotor effects.  相似文献   
56.
Mental health problems are common in children and adolescents, yet evidence-based treatments are hard to access. Self-help interventions can increase such access. The aim of this paper was to conduct a systematic review and meta-analysis of the use of guided and unguided self-help for children and young people with symptoms of common mental health disorders. In contrast to previous reviews of self-help in children, all types of self-help and multiple mental health disorders were investigated in order to increase power to investigate potential moderators of efficacy. Importantly, studies with control arms as well as those comparing against traditional face-to-face treatments were included. Fifty studies (n = 3396 participants in self-help/guided self-help conditions) met the inclusion criteria. Results demonstrated a moderate positive effect size for guided and unguided self-help interventions when compared against a control group (n = 44; g = 0.49; 95% CI: 0.37 to 0.61, p < .01) and a small but significant negative effect size when compared to other therapies (n = 15; g = −0.17; 95% CI: –0.27 to –0.07, p < .01). Few potential moderators had a significant effect on outcome. Most comparisons resulted in significant heterogeneity and therefore results are interpreted with caution.  相似文献   
57.
58.
Coronavirus disease 2019 (COVID-19) due to SARS-CoV-2 is associated with a wide spectrum of disease, ranging from asymptomatic infection to acute respiratory distress syndrome. Some biomarkers may predict disease severity. Among them, the anti-SARS-CoV-2 antibody response has been related to severe disease. The aim of this study was to assess the correlation between the anti-SARS-CoV-2 serological response and COVID-19 outcome. Demographic, clinical, and biological data from nasopharyngeal-PCR confirmed COVID-19 hospitalized patients were prospectively collected between April and August 2020 at our institution. All patients had serial weekly serology testing for a maximum of three blood samples or until discharge. Two different serological assays were used: a chemiluminescent assay and an in-house developed Luminex immunoassay. Kinetics of the serological response and correlation between the antibody titers and outcome were assessed. Among the 70 patients enrolled in the study, 22 required invasive ventilation, 29 required non-invasive ventilation or oxygen supplementation, and 19 did not require any oxygen supplementation. Median duration of symptoms upon admission for the three groups were 13, 8, and 9 days, respectively. Antibody titers gradually increased for up to 3 weeks since the onset of symptoms for patients requiring oxygen supplementation with significantly higher antibody titers for patients requiring invasive ventilation. Antibody titers on admission were also significantly higher in severely ill patients and serology performed well in predicting the necessity of invasive ventilation (AUC: 0.79, 95% CI: 0.67–0.9). Serology testing at admission may be a good indicator to identify severe COVID-19 patients who will require invasive mechanical ventilation.  相似文献   
59.
60.
Adsorption of particles across interfaces has been proposed as a way to create adhesion between hydrogels and biological tissues. Here, we explore how this particle bridging approach can be applied to attach a soft polymer substrate to biological tissues, using bioresorbable and nanostructured hydroxyapatite–bioactive glass microparticles. For this, microparticles of aggregated flower-like hydroxyapatite and bioactive glass (HA–BG) were synthesized via a bioinspired route. A deposition technique using suspension spreading was developed to tune the coverage of HA–BG coatings at the surface of weakly cross-linked poly(beta-thioester) films. By varying the concentration of the deposited suspensions, we produced coatings having surface coverages ranging from 4% to 100% and coating densities ranging from 0.02 to 1.0 mg cm−2. The progressive dissolution of these coatings within 21 days in phosphate-buffered saline was followed by SEM. Ex vivo peeling experiments on pig liver capsules demonstrated that HA–BG coatings produce an up-to-two-fold increase in adhesion energy (9.8 ± 1.5 J m−2) as compared to the uncoated film (4.6 ± 0.8 J m−2). Adhesion energy was found to increase with increasing coating density until a maximum at 0.2 mg cm−2, well below full surface coverage, and then it decreased for larger coating densities. Using microscopy observations during and after peeling, we show that this maximum in adhesion corresponds to the appearance of particle stacks, which are easily separated and transferred onto the tissue. Such bioresorbable HA–BG coatings give the possibility of combining particle bridging with the storage and release of active compounds, therefore offering opportunities to design functional bioadhesive surfaces.

Coatings of hydroxyapatite–bioactive glass microparticles are proposed as a way to create adhesion between hydrogels and biological tissues using adsorption of the microparticles across the interface.  相似文献   
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