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We present an easily implemented wavefront correction scheme that has been specifically designed for in-vivo brain imaging. The system can be implemented with a single liquid crystal spatial light modulator (LCSLM), which makes it compatible with existing patterned illumination setups, and provides measurable signal improvements even after a few seconds of optimization. The optimization scheme is signal-based and does not require exogenous guide-stars, repeated image acquisition or beam constraint. The unconstrained beam approach allows the use of Zernike functions for aberration correction and Hadamard functions for scattering correction. Low order corrections performed in mouse brain were found to be valid up to hundreds of microns away from the correction location.OCIS codes: (170.2520) Fluorescence microscopy, (010.1080) Active or adaptive optics, (170.5810) Scanning microscopy  相似文献   
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Physiological and pathological factors affecting intracellular red cell vitamin B6 metabolism in normal, anaemic and alcoholic man were studied using a new assay for pyridoxine kinase (PnK) together with saturated and total aspartate aminotransferase (EGOT) activities as indirect indices of intracellular pyridoxal 5-phosphate (PLP) availability. In studies of anaemic states, subjects with iron deficiency anaemia demonstrated elevated levels of both PnK and saturated EGOT, while seven out of 17 subjects with inflammatory anaemia had subnormal PnK but variable saturated EGOT activities. Despite a high incidence of complicating inflammatory disease, alcoholic subjects with or without ring sideroblastic anaemia had elevated levels of both PnK and saturated EGOT. As judged from the saturated EGOT and the ratio unsaturated EGOT/saturated EGOT, intracellular PLP availability was always appropriate to the higher levels of PnK activity.  相似文献   
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Anal cancer is one of the most common non‐AIDS‐defining malignancies in the era of combination antiretroviral therapy. Its precursor lesion, anal intraepithelial neoplasia (AIN), is highly prevalent in HIV‐infected populations. More than 90% of anal squamous cell cancers are attributable to human papillomavirus (HPV). While the biology of HPV‐related intraepithelial neoplasia is consistent across lower anogenital sites, the natural history of AIN is not well established and cannot be assumed to be identical to that of cervical intraepithelial neoplasia. Screening strategies to prevent anal cancer should be developed based on robust natural history data in HIV‐infected and uninfected populations. Likewise, treatments need to be tested in randomized clinical trials, and reserved for those at significant risk of progression to cancer. This review covers the epidemiology, pathogenesis and immunology of HPV infection, AIN and anal cancer, and summarizes the current diagnosis, screening and treatment strategies in HIV‐infected adults.  相似文献   
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Transfecting genes into tumors, to upregulate major histocompatibility complex (MHC) class I and class II molecules and inhibit MHC class II associated invariant chain (Ii), induces a potent anti-tumor immune response when preceded by tumor irradiation, in murine RM-9 prostate carcinoma. The transfected genes are cDNA plasmids for interferon-gamma (pIFN-gamma), MHC class II transactivator (pCIITA), an Ii reverse gene construct (pIi-RGC), and a subtherapeutic dose of adjuvant IL-2 (pIL-2). Responding mice rejected challenge with parental tumor and demonstrated tumor-specific cytotoxic T lymphocytes (CTLs). We have extended our investigation to determine the relative roles of each one of the four plasmids pIFN-gamma, pCIITA, pIi-RGC, and pIL-2 in conjunction with radiation for the induction of a curative immune response. Upregulation of MHC class I with pIFN-gamma or class II with pCIITA, separately, does not lead to a complete response even if supplemented with pIL-2 or pIi-RGC. An optimal and specific antitumor response is achieved in more than 50% of the mice when, after tumor irradiation, tumor cells are converted in situ to a MHC class I+/class II+/Ii- phenotype with pIFN-gamma, pCIITA, pIi-RGC, and pIL-2. We demonstrate further that both CD4+ helper T cells and CD8+ cytotoxic T cells are essential for induction of an antitumor response because in vivo depletion of either subset abrogates the response. The radiation contributes to the gene therapy by causing tumor debulking and increasing the permeability of tumors to infiltration of inflammatory cells.  相似文献   
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ObjectiveTo evaluate the ability of preoperative neutrophil-lymphocyte ratio (NLR) to predict pathologic upstaging and nonorgan-confined (NOC) (≥pT3) disease.Methods and materialsAfter institutional review board approval, the records of consecutive patients undergoing radical cystectomy (RC) for urothelial carcinoma from 2002 to 2012 at the University of Wisconsin Hospital were reviewed. A total of 102 patients with NLR within 100 days of surgery were eligible for analysis. The primary outcome was difference in stage from preoperative assessment to time of RC. Differences in preoperative NLR between groups were evaluated with an unequal variance t test. A univariate analysis assessed whether NLR, preoperative stage, grade, associated lymphovascular invasion, preoperative hydronephrosis, gender, previous pelvic radiotherapy, previous intravesical bladder cancer treatments, or nodal stage were related to upstaging. Multivariate analyses were performed to evaluate the relationship of NLR to upstaging and relative organ-confined (≤pT2) and NOC disease.ResultsOf 390 consecutive patients undergoing RC, 102 patients met study criteria. Overall, 55 (53.9%) patients were upstaged, 25 (25.5%) were unchanged, and 21 (20.6%) were downstaged. Fifty-one patients (50%) were upstaged to more advanced disease (≥pT3). NLR and preoperative hydronephrosis were significantly related to pathologic tumor staging. NLR, preoperative hydronephrosis, and preoperative tumor stage were significantly related to upstaging to NOC disease. Patients who were upstaged to≥pT3 demonstrated statistically significant greater NLRs (4.33±0.87) compared with patients who remained at≤pT2 stage (2.66±0.29) (P<0.001).ConclusionsPreoperative NLR is a simple measurement that can be used to identify high-risk patients who may be upstaged at the time of RC and may benefit from neoadjuvant chemotherapy.  相似文献   
49.
The immune response is influenced by genetic and epigenetic factors, as well as disease and environmental factors. The term ‘epigenetics’ describes changes in the genome that influence the gene expression without altering the DNA sequence. In contrast to genetic changes in the DNA, epigenetic changes are reversible and are influenced by environmental factors. The aim of this study is to review the literature on epigenetic modifications with respect to oral health and inflammatory conditions in the oral cavity and to discuss the potential use of this new research field for the dental hygienists' and/or dentists' clinical work. Relevant publications were identified using the PubMed database without limits. The searches were conducted during January to March 2012 and resulted in articles published between 1912 and 2012. Key factors such as environment, diet, smoking, bacteria and inflammation were identified to be relevant to oral health. The result of this review article shows that there is a void in the research on epigenetics in relation to oral health. Identification of epigenetic modifications correlating with oral health may not only present a link between the influence of genetics and that of the environment on oral diseases but also provide new treatment models and tools for the dental professionals.  相似文献   
50.
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