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71.
Animal models of anxiety in mice   总被引:1,自引:0,他引:1  
Among the multiple possibilities to study human pathologies, animal models remain one of the most used pathways. They allow to access to unavailable answers in human patients and to learn about mechanisms of action of drugs. Primarily developed with rats, animal models in anxiety have been adapted with a mixed success for mice, an easy-to-use mammal with better genetic possibilities than rats. In this review, we have focused on the most used animal models in anxiety in mice. Both conditioned and unconditioned models are described, to represent all types of animal models of anxiety. Behavioural studies require strong care for variable parameters, linked to environment, handling or paradigm; we have discussed about this topic. Finally, we focused on the consequences of re-exposure to the apparatus. Test-retest procedures can bring in new answers, but should be deeply studied, to revalidate the whole paradigm as an animal model of anxiety.  相似文献   
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73.
OBJECTIVE: Post-stroke shoulder pain is a common phenomenon in hemiplegia and impedes rehabilitation. The aim of this study was to identify a possible relationship between post-stroke shoulder pain, scapula resting position and shoulder motion. METHODS: Shoulder kinematics of 27 patients after stroke (17 men) were compared with 10 healthy age-matched control subjects. Using an electromagnetic tracking device, the kinematics of both the contralateral and ipsilateral (i.e. paretic and non-paretic) arm during active and passive abduction and forward flexion were measured and expressed in Euler angles. RESULTS: Scapular lateral rotation relative to the thorax was increased in patients with post-stroke shoulder pain compared with both patients without post-stroke shoulder pain and control subjects at rest as well as during arm abduction and forward flexion. Additionally, glenohumeral elevation was decreased in patients with post-stroke shoulder pain during passive abduction. No differences were found regarding scapula position (displacement relative to the thorax). CONCLUSION: In patients with post-stroke shoulder pain a particular kinematical shoulder pattern was established, characterized by enhanced scapular lateral rotation and diminished glenohumeral mobility.  相似文献   
74.
Background: Driving under the influence (DUI) is a major cause of death and disability. Although a broad array of programs designed to curb DUI incidents are currently offered to both first-time and recidivist DUI offenders, existing evaluations of the effectiveness of these programs have reported mixed results. Objective: To synthesize the results of DUI program evaluations and determine the strength of the available evidence for reducing recidivism for different types of programs. Methods: A systematic review of all EBSCO databases, EMBASE, PubMed, ProQuest, Sociological Abstracts and TRIS was conducted to identify evaluations of treatments/interventions to prevent DUI offenses. Additional articles were identified from reference lists of relevant articles. Results: A total of 42 relevant studies were identified by the search strategy. Of these, 33 utilized non-experimental evaluation designs or reported insufficient data to allow effect sizes to be calculated, making meta-analysis unfeasible. Evaluations of several different program types reported evidence of some level of effectiveness. Conclusion: Because of the general lack of high quality evidence assessing the effectiveness of DUI prevention programs, it is not possible to make conclusive statements about the types of programs that are likely to be most effective. Nonetheless, there was some evidence to support the effectiveness of programs that utilize intensive supervision and education. There is a need for future evaluations to adopt more scientifically rigorous research designs to establish the effects of these programs.  相似文献   
75.

Background

Lynch syndrome (LS) diagnosis is underestimated, and most of the patients remain undetected after colorectal resections. The study aims to assess the frequency of LS in patients undergoing surgical treatment for colorectal cancer (CRC).

Methods

A total of 458 CRC patients were operated from January 2005 to December 2008. Positive CRC family history (FH) was present in 118 (25.8%) patients. Histologic sections were reviewed for microsatellite instability (MSI) criteria (Bethesda guidelines), immunohistochemical (IHC) analysis for MLH1, MSH2, MSH6, PMS2 proteins, through the avidin-biotin-peroxidase complex, MSI (BAT-25, BAT-26, NR-21, NR-24 and MONO-27) and BRAF somatic mutation.

Results

Of the 118 patients with FH, 61 (51.69%) met at least one of the revised Bethesda criteria. IHC was abnormal in 8 (13.1%) and MSI in 12 patients (20%). BRAF was negative in all cases. MSI histopathological included: intratumoral lymphocytes (47.5%), expansive tumors (29.5%) mucinous component (27.8%) and Crohn’s like reaction in (14.7%). There was an association between the revised Bethesda criteria with: sex, mucinous histology and Crohn’s like reaction; MSI and IHC with PMS2 and MLH1. Revised Bethesda criteria 4 had 10.6 increased chances to display positive MSI. We have proposed a score to contribute as a practical tool in the diagnosis of LS.

Conclusions

The frequence of LS in resected CRC patients was 2.6%. The criterion 4 Revised Bethesda was associated more strongly with the presence of MSI.  相似文献   
76.
Functional deterioration of the peritoneal membrane in patients on peritoneal dialysis has been described as being the result of a combination of neoangiogenesis and fibrosis. Glucose, glucose degradation products, and the unphysiological pH of the dialysate solution contribute to these changes. Although newer solutions clearly perform better in terms of their biocompatibility in an in vitro setting and in animal models, the benefit of such solutions over older solutions in the clinical setting is so far unproven. The difficulties in showing a benefit of the newer, more biocompatible solutions in the clinical setting can be explained by the fact that other factors also affect the properties of the peritoneal membrane. These factors are often neglected in clinical studies, which results in unnoticed differences in case-mix and blurs the potential impact of the novel solutions. However, many of these factors are modifiable, and attention should be paid to them in clinical practice to maintain the integrity of the peritoneal membrane. This Review focuses on factors that potentially influence the integrity of the peritoneal membrane, other than those associated with the peritoneal dialysis fluid itself.  相似文献   
77.
PurposeA unique standardized international data set from adolescent girls in 34 countries in Europe and North America participating in the Health Behaviour in School-aged Children Study (HBSC) is used to investigate the contribution of body mass index (BMI) at individual and country level to cross-national differences in age at menarche.MethodsTwo independent nationally representative survey data sets from 15-year-olds (n = 27,878, in 34 countries, year = 2005/2006) and 11-year-olds (n = 18,101, in 29 countries, year = 2001/2002) were analyzed. The survey instrument is a self-report questionnaire. Median age at menarche and 95% confidence intervals (CIs) were estimated using Kaplan–Meier analysis. Hierarchical models were used to assess the relationship between BMI and age at menarche (months). “Country-level obesity” was measured by prevalence of overweight/obesity (%) in each country.ResultsCountry-level median age at menarche ranged between 12 years and 5 months and 13 years and 5 months. Country-level prevalence of overweight among 15-year-old girls ranged from 4% to 28%. Age at menarche was inversely associated with individual BMI (unstandardized regression coefficient beta = ?1.01; 95% CI, ?1.09 to ?.94) and country-level aggregate overweight at age 11 (unstandardized regression coefficient beta = ?.25; 95% CI, ?.43 to ?.08). Individual- and country-level measures of BMI account for 40% of the country-level variance in age at menarche.ConclusionsThe findings add to the evidence that obesity in childhood is a risk factor for early puberty in girls and accounts for much of the cross-national variation in age at menarche. Future HBSC surveys can track this relationship in the wake of the obesity “epidemic.”  相似文献   
78.
Comparative research on health and health inequalities has recently started to establish a welfare regime perspective. The objective of this study was to determine whether different welfare regimes are associated with health and health inequalities among adolescents. Data were collected from the ‘Health Behaviour in School‐aged Children’ study in 2006, including 11‐ to 15‐year‐old students from 32 countries (N = 141,091). Prevalence rates and multilevel logistic regression models were calculated for self‐rated health (SRH) and health complaints. The results show that between 4 per cent and 7 per cent of the variation in both health outcomes is attributable to differences between countries. Compared to the Scandinavian regime, the Southern regime had lower odds ratios for SRH, while for health complaints the Southern and Eastern regime showed high odds ratios. The association between subjective health and welfare regime was largely unaffected by adjusting for individual socioeconomic position. After adjustment for the welfare regime typology, the country‐level variations were reduced to 4.6 per cent for SRH and to 2.9 per cent for health complaints. Regarding cross‐level interaction effects between welfare regimes and socioeconomic position, no clear regime‐specific pattern was found. Consistent with research on adults this study shows that welfare regimes are important in explaining variations in adolescent health across countries.  相似文献   
79.
Florianópolis, a city located in the Santa Catarina State in southern Brazil, is the national leading producer of bivalve mollusks. The quality of bivalve mollusks is closely related to the sanitary conditions of surrounding waters where they are cultivated. Presently, cultivation areas receive large amounts of effluents derived mainly from treated and non-treated domestic, rural, and urban sewage. This contributes to the contamination of mollusks with trace metals, pesticides, other organic compounds, and human pathogens such as viruses, bacteria, and protozoan. The aim of this study was to perform a thorough diagnosis of the shellfish growing areas in Florianópolis, on the coast of Santa Catarina. The contamination levels of seawater, sediments, and oysters were evaluated for their microbiological, biochemical, and chemical parameters at five sea sites in Florianópolis, namely three regular oyster cultivation areas (Sites 1, 2, and oyster supplier), a polluted site (Site 3), and a heavily polluted site (Site 4). Samples were evaluated at day zero and after 14 days. Seawater and sediment samples were collected just once, at the end of the experiment. Antioxidant defenses, which may occur in contaminated environments in response to the increased production of reactive oxygen species (ROS) by organisms, were analyzed in oysters, as well as organic compounds (in oysters and sediment samples) and microbiological contamination (in oysters and seawater samples). The results showed the presence of the following contaminants: fecal coliforms in seawater samples (four sites), human adenovirus (all sites), human noroviruses GI and GII (two sites), Hepatitis A viruses (one site), JC Polyomavirus in an oyster sample from the oyster supplier, Giardia duodenalis cysts, and Cryptosporidium sp oocysts (one site). Among organochlorine pesticides, only DDT (dichlorodiphenyltrichloroethane) and HCH (hexachlorocyclohexane) were detected in some sediment and oysters samples in very low levels; site 4 had the highest concentrations of total aliphatic hydrocarbons, PAHs, and linear alkylbenzenes (LABs) found either in oysters or in sediment samples. The major concentration of fecal sterol coprostanol was found at site 4, followed by site 3. After 14 days of allocation in the four selected sites, there was a significant difference in the enzymes analyzed at the monitored spots. The detection of different contaminants in oysters, seawater, and sediment samples in the present study shows the impact untreated or inadequately treated effluents have on coastal areas. These results highlight the need for public investment in adequate wastewater treatment and adequate treatment of oysters, ensuring safe areas for shellfish production as well as healthier bivalve mollusks for consumption.  相似文献   
80.
Peer victimization is a common problem among school-aged children, and those with chronic conditions are at an increased risk. A systematic review of the literature was carried out to explore the increased risk of peer victimization among children with chronic conditions compared with others, considering a variety of chronic conditions; and to assess intervention programs designed to reduce negative attitudes or peer victimization at school toward children with chronic conditions. Various data sources were used (PubMed, ERIC, PsycINFO, Web of Science), and 59 studies published between 1991 and 2011 and mainly carried out in North American and European countries were included in the review. A higher level of peer victimization among children with chronic conditions was shown for each type of condition explored in this review (psychiatric diagnoses, learning difficulties, physical and motor impairments, chronic illnesses, and overweight). Despite a substantial number of studies having shown a significant association between chronic conditions and peer victimization, intervention studies aiming to reduce bullying among these children were rarely evaluated. The findings of this review suggest a growing need to develop and implement specific interventions targeted at reducing peer victimization among children with chronic conditions.  相似文献   
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