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51.
Abstract

Treatment process and outcome data for 225 consecutive admissions to a rehabilitation program for the homeless were reviewed. The Northeast Program Evaluation Center's criteria were employed to evaluate participation and outcome (e.g., general, employment, and housing) for participants. Significant relationships were found between predominant personality features and degree of participation in program and living arrangements at discharge.  相似文献   
52.
Permanent sensorineural hearing loss is a major medical problem and is due to the loss of hair cells and subsequently spiral ganglion neurons in the cochlea. Since these cells lack the capacity of renewal in mammals, their regeneration would be an optimal solution to reverse hearing loss. In other tissues, decellularized extracellular matrix (ECM) has been used as a mechanical and biochemical scaffold for the induction of stem and other cells toward a target tissue phenotype. Such induced cells have been used for tissue and organ transplants in preclinical animal and human clinical applications. This paper reports for the first time the decellularization of the cochlea and identification of remaining laminin and collagen type IV as a first step in preparing an ECM scaffold for directing stem cells toward an auditory lineage. Fresh ear tissues were removed from euthanized mice, a rat and a human and processed for decellularization using two different detergent extraction methods. Cochleas were imaged with scanning thin-sheet laser imaging microscopy (sTSLIM) and brightfield microscopy. Detergent treatment of fresh tissue removed all cells as evidenced by lack of H&E and DNA staining of the membranous labyrinth while preserving components of the ECM. The organ of Corti was completely removed, as were spiral ganglion neurons, which appeared as hollow sheaths and tubes of basal lamina (BL) material. Cells of the stria vascularis were removed and its only vestige left was its laterally linking network of capillary BL that appeared to “float” in the endolymphatic space. Laminin and type IV collagen were detected in the ECM after decellularization and were localized in vascular, neural and epithelial BL. Further work is necessary to attempt to seed neural and other stem cells into the decellularized ECM to hopefully induce differentiation and subsequent in vivo engraftment into damaged cochleas.  相似文献   
53.
54.
SV40 is a DNA tumor virus thrust upon human populations primarily as a contaminant in various vaccine preparations. Some estimates suggest that millions of people are currently infected with the virus. The virus causes primary brain tumors, bone tumors, lymphomas, and mesotheliomas when injected into some rodent models. It has also been detected in a similar spectrum of human tumors. However, epidemiological studies have failed to conclusively demonstrate a higher incidence of disease in affected populations. To date, over 60 reports from 49 different laboratories have shown SV40 sequences in tissues from human cancer patients. Six studies, however, have failed to detect evidence of virus in similar tissues. Some have suggested that SV40 may act as a cocarcinogen with asbestos to cause mesothelioma formation, or that it may be responsible for the 10–20% of mesotheliomas with no reported history of asbestos exposure. This report briefly covers the historical evidence for SV40 carcinogenesis and then covers experiments now underway to better understand the role of SV40 in human mesotheliomas.  相似文献   
55.
Self-controlled hyperthermia is a non-invasive technique used to kill or destroy cancer cells while preserving normal surrounding tissues. We have explored bulk magnetic Ni-Si and Ni-Al alloys as a potential thermoseeds. The structural, magnetic and magnetocaloric properties of the samples were investigated, including saturation magnetisation, Curie temperature (TC), and magnetic and thermal hysteresis, using room temperature X-ray diffraction and magnetometry. The annealing time, temperature and the effects of homogenising the thermoseeds were studied to determine the functional hyperthermia applications. The bulk Ni-Si and Ni-Al binary alloys have Curie temperatures in the desired range, 316?K–319?K (43?°C–46?°C), which is suitable for magnetic hyperthermia applications. We have found that TC strictly follows a linear trend with doping concentration over a wide range of temperature. The magnetic ordering temperature and the magnetic properties can be controlled through substitution in these binary alloys.  相似文献   
56.
57.

Background  

Few studies have explored exercise and motivational patterns of cardiac rehabilitation patients in the long term.  相似文献   
58.
Objective: This paper explores possible connections among existing literature on parental stress, augmentative and alternative communication (AAC), and use of mobile technology for persons with autism spectrum disorder (ASD). Methods: A narrative review of the literature. Results: Parental support contributes to positive outcomes for children who use AAC. Parents identify communication as a high priority, but describe the process as challenging. AAC is often used with children with ASD, a population in which parental stress is especially high. Though there is research evidence that mobile technology is a promising tool for individuals with ASD, potentially misleading media anecdotes exist, and the effects on parental expectations and stress remain unstudied questions. Conclusion: Increased understanding of the connections in these research areas should help clarify the potential impact of mobile technologies on parental stress level, help to define appropriate future research directions, and contribute to development of appropriate caregiver training.  相似文献   
59.
Propiconazole (PPZ) is a conazole fungicide that is not mutagenic, clastogenic, or DNA damaging in standard in vitro and in vivo genetic toxicity tests for gene mutations, chromosome aberrations, DNA damage, and cell transformation. However, it was demonstrated to be a male mouse liver carcinogen when administered in food for 24 months only at a concentration of 2,500 ppm that exceeded the maximum tolerated dose based on increased mortality, decreased body weight gain, and the presence of liver necrosis. PPZ was subsequently tested for mutagenicity in the Big Blue® transgenic mouse assay at the 2,500 ppm dose, and the result was reported as positive by Ross et al. ([2009]: Mutagenesis 24:149‐152). Subsets of the mutants from the control and PPZ‐exposed groups were sequenced to determine the mutation spectra and a multivariate clustering analysis method purportedly substantiated the increase in mutant frequency with PPZ (Ross and Leavitt. [2010]: Mutagenesis 25:231‐234). However, as reported here, the results of the analysis of the mutation spectra using a conventional method indicated no treatment‐related differences in the spectra. In this article, we re‐examine the Big Blue® mouse findings with PPZ and conclude that the compound does not act as a mutagen in vivo. © Environ. Mol. Mutagen. 2012. Published 2011 Wiley Periodicals, Inc.  相似文献   
60.
the mechanistic target of rapamycin(m tor) is an intracellular protein kinase that functions as an energy and nutrient sensor in the cellular microenvironment of neurons. modulation of m tor is vital when nutrient and energy sources become limited. hypoxia, traumatic brain injury, cellular energy states, and growth factors all regulate the phosphorylation and total levels of m tor in cells. alterations in the microenvironment induce transduction of signals to downstream proteins by m tor allowing for cells to make the necessary adjustments to counteract stressors and survive. progesterone, a hydrophobic steroid hormone, has been shown in studies of non-neural tissue to be a suppressor of m tor and modulator of m tor phosphorylation. our study tested the effects of progesterone on m tor expression following traumatic brain injury. c57 bl/6 mice were treated with progesterone(8 mg/kg) at 1(intraperitoneal), 6(subcutaneous), 24(subcutaneous), and 48(subcutaneous) hours post closed skull traumatic brain injury. the hippocampus was then harvested 72 hours post injury and prepared for western blot analysis. we found that progesterone significantly decreased total m tor levels in all groups compared to sham treated with vehicle. this was further confirmed by immunostaining showing decreased cytoplasmic m tor levels compared to sham. our study shows progesterone is a significant modulator of m tor levels in the hippocampus of mice following traumatic brain injury.  相似文献   
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