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781.
Huntington's disease is caused by a trinucleotide repeat expansion (CAG)n in the gene coding for Huntingtin (Htt) and is one of the several polyglutamine diseases. Its physical symptoms occur in a large range of ages, with a mean occurrence in a person's late 40's and early 50's. Almost all references indicated that if the age of onset is below 20 years then it is known as juvenile HD. Our case was an Iranian family with 4 affected siblings (2 sisters and 2 brothers). In addition to 4 affected children, they had 5 normal male progenies. There was no any other case in their family history. The onset age of the disease in our case family was 20 to 25 years. Their parents were unaffected and nonconsanguineous. Analysis of the pathogenic (CAG)n repeat region of the HD gene for the affected members have showed an expansion allele with 46, 50, 46, and 44 repeats in 4 affected siblings. Our results indicated that the age of 20 years maybe is not a stable limit point for all cases of juvenile HD, and perhaps onset ages are related with the CAG repeat sizes in such individuals.  相似文献   
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783.
We used a mobile positron emission tomography (PET) scanner positioned within the proton therapy treatment room to study the feasibility of proton range verification with an in-room, stand-alone PET system, and compared with off-line equivalent studies. Two subjects with adenoid cystic carcinoma were enrolled into a pilot study in which in-room PET scans were acquired in list-mode after a routine fractionated treatment session. The list-mode PET data were reconstructed with different time schemes to generate in-room short, in-room long and off-line equivalent (by skipping coincidences from the first 15 min during the list-mode reconstruction) PET images for comparison in activity distribution patterns. A phantom study was followed to evaluate the accuracy of range verification for different reconstruction time schemes quantitatively. The in-room PET has a higher sensitivity compared to the off-line modality so that the PET acquisition time can be greatly reduced from 30 to <5 min. Features in deep-site, soft-tissue regions were better retained with in-room short PET acquisitions because of the collection of (15)O component and lower biological washout. For soft tissue-equivalent material, the distal fall-off edge of an in-room short acquisition is deeper compared to an off-line equivalent scan, indicating a better coverage of the high-dose end of the beam. In-room PET is a promising low cost, high sensitivity modality for the in vivo verification of proton therapy. Better accuracy in Monte Carlo predictions, especially for biological decay modeling, is necessary.  相似文献   
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786.
We report here the detailed radiosynthesis of [18F] mG4P027 , a metabotropic glutamate receptor 4 (mGluR4) PET radiotracer, which showed superior properties to the currently reported mGluR4 radiotracers. The radiosynthesis in the automated system has been challenging, therefore we disclose here the major limiting factors for the synthesis via step-by-step examination. And we hope this thorough study will help its automation for human use in the future.  相似文献   
787.
Autosomal recessive cerebellar ataxias are a group of heterogeneous early‐onset progressive disorders that some of them are treatable. We performed a 4‐year follow‐up for 25 patients who had treatable ataxia. According to our study, patients would benefit from early detection of treatable ataxia, close observation, and follow‐up.  相似文献   
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789.
This study evaluated the antimicrobial efficacy of grape seed extract medicament combined with Nd:YAG laser, against Enterococcus faecalis, Staphylococcus aureus and Candida albicans biofilms. Root canals infected with 4-week-old biofilms were divided into five groups (n = 11): calcium hydroxide, 6.5% GSE, Nd:YAG laser (1064 nm, 1.5 w, 15 Hz and 100 mj) and 6.5% GSE followed by Nd:YAG laser and normal saline (control). Dentin chips were collected using Gates–Glidden and cultured to obtain colony-forming units. Statistical analysis was performed using Kruskal–Wallis and Mann–Whitney U test. GSE showed higher antibacterial activity against all species investigated compared to Ca(OH)2. However, the lowest microbial count was obtained using a combination of GSE and Nd:YAG laser (p < 0.001). No significant difference in the susceptibility of tested pathogens to each of the protocols was observed (p > 0.05). Application of Nd:YAG laser following GSE medicament is efficient against endodontic biofilms; also, GSE can be considered as an alternative to Ca(OH)2 dressing.  相似文献   
790.
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