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991.
Electromagnetic radiation (EMR) is emitted from electromagnetic fields that surround power lines, household appliances and mobile phones. Research has shown that there are connections between EMR exposure and cancer and also that exposure to EMR may result in structural damage to neurons. In a study by Salford et al. (Environ Health Perspect 111:881–883, 2003) the authors demonstrated the presence of strongly stained areas in the brains of rats that were exposed to mobile phone EMR. These darker neurons were particularly prevalent in the hippocampal area of the brain. The aim of our study was to further investigate the effects of EMR. Since the hippocampus is involved in learning and memory and emotional states, we hypothesised that EMR will have a negative impact on the subject’s mood and ability to learn. We subsequently performed behavioural, histological and biochemical tests on exposed and unexposed male and female rats to determine the effects of EMR on learning and memory, emotional states and corticosterone levels. We found no significant differences in the spatial memory test, and morphological assessment of the brain also yielded non-significant differences between the groups. However, in some exposed animals there were decreased locomotor activity, increased grooming and a tendency of increased basal corticosterone levels. These findings suggested that EMR exposure may lead to abnormal brain functioning.  相似文献   
992.
993.
Purpose  The effects of reciprocal transplantation of meiosis-II chromosomes between senescent and young mouse oocytes were evaluated based on pre- and post-implantation development ability of resultant embryos. Methods  Karyoplasts including meiosis-II chromosomes of oocytes from senescent Rockefeller mouse/Ms-Rb(6, 15) females (10 to 12 months, age-related infertile mice) were transferred into cytoplasts of oocytes from young F1 females (3 to 5 months). Reconstructed oocytes were fertilized in vitro, and then the resultant embryos were cultured in vitro and transferred to recipient mice. Results  The reconstructed oocytes that consisted of aged-karyoplasts and young-cytoplasts showed significantly improved embryonic development (from 23.2% to 30.0%) and development to term (from 6.3% to 27.1%, P < 0.05) as compared with the oocytes reconstructed from young-karyoplasts and aged-cytoplasts. Conclusions  The present study showed successful rejuvenation for age-related infertility using transplantation of meiosis-II chromosomes in animal experimental models. Capsule Transplantation of meiosis-II chromosomes of senescent mouse oocytes into cytoplasts of young mouse oocytes improves subsequent embryonic and fetal development until birth.  相似文献   
994.

Background  

Parkinson disease (PD) causes physical disability that negatively affects the quality of life of the sufferer's and their families. There are no Parkinson's disease (PD) social science studies published from Africa. This paper presents findings from a qualitative research study on how PD is perceived and treated in a population of approximately 161,000 within a demographic surveillance site in rural Tanzania.  相似文献   
995.

Background  

Interventions are needed which can successfully modify more than one disease risk factor at a time, but much remains to be learned about the acceptability, feasibility, and effectiveness of multiple risk factor (MRF) interventions. To address these issues and inform future intervention development, we conducted a randomized pilot trial (n = 52). This study was designed to assess the feasibility and acceptability of the Step Up program, a MRF cognitive-behavioral program designed to improve participants' mental and physical well-being by reducing depressive symptoms, promoting smoking cessation, and increasing physical activity.  相似文献   
996.

Background  

Breathlessness causes significant burden in our community but the underlying socio-demographic and lifestyle factors that may influence it are not well quantified. This study aims to define these predictors of chronic breathlessness at a population level.  相似文献   
997.
Maxillary antral mucocoeles have an incidence of only 3–10%. Mucocoeles are more commonly seen in the frontoethmoidal region. We present one such rare case of a 52-year-old lady who came to us with complaints of pain and swelling of the left cheek of 4 months duration. Clinical examination and investigation revealed a giant maxillary sinus mucocoele which was duly treated surgically. We discuss its classical presentation and management since such large mucocoeles are not often seen in the maxillary sinus.  相似文献   
998.
999.

Objective  

To compare the effectiveness of percutaneous catheter drainage (PCD) and percutaneous needle aspiration (PNA) in the management of large (>10 cm diameter) liver abscesses.  相似文献   
1000.
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