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11.
Pyogenic granuloma is a lobular capillary hemangioma that mostly occurs on the skin, but it is also encountered on the mucosal surface of the oral cavity. Only a few cases in other parts of the digestive tract have been reported in Japanese patients. In this report, two Caucasian patients are described, who presented with gastrointestinal bleeding due to the presence of a pyogenic granuloma. One was located in the distal esophagus and could be treated with local excision and laser-photocoagulation therapy. The other one was located in the small intestine and was removed by surgical resection. Although extremely rare, pyogenic granuloma as a cause of gastrointestinal bleeding needs consideration. The lesion is benign, presumably reactive and can be adequately treated by excision or laser photocoagulation. Immunohistochemistry and/or polymerase chain reaction for herpesvirus 8 can reliably distinguish pyogenic granuloma from Kaposis sarcoma, an important differential diagnosis.  相似文献   
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In this study, hyperpolarized 129Xe MR ventilation and 1H anatomical images were obtained from three subject groups: young healthy volunteers (HVs), subjects with chronic obstructive pulmonary disease (COPD) and age‐matched controls (AMCs). Ventilation images were quantified by two methods: an expert reader‐based ventilation defect score percentage (VDS%) and a semi‐automated segmentation‐based ventilation defect percentage (VDP). Reader‐based values were assigned by two experienced radiologists and resolved by consensus. In the semi‐automated analysis, 1H anatomical images and 129Xe ventilation images were both segmented following registration to obtain the thoracic cavity volume and ventilated volume, respectively, which were then expressed as a ratio to obtain the VDP. Ventilation images were also characterized by generating signal intensity histograms from voxels within the thoracic cavity volume, and heterogeneity was analyzed using the coefficient of variation (CV). The reader‐based VDS% correlated strongly with the semi‐automatically generated VDP (r = 0.97, p < 0.0001) and with CV (r = 0.82, p < 0.0001). Both 129Xe ventilation defect scoring metrics readily separated the three groups from one another and correlated significantly with the forced expiratory volume in 1 s (FEV1) (VDS%: r = –0.78, p = 0.0002; VDP: r = –0.79, p = 0.0003; CV: r = –0.66, p = 0.0059) and other pulmonary function tests. In the healthy subject groups (HVs and AMCs), the prevalence of ventilation defects also increased with age (VDS%: r = 0.61, p = 0.0002; VDP: r = 0.63, p = 0.0002). Moreover, ventilation histograms and their associated CVs distinguished between subjects with COPD with similar ventilation defect scores, but visibly different ventilation patterns. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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The earliest studies on ‘disability glare’ date from the early 20th century. The condition was defined as the negative effect on visual function of a bright light located at some distance in the visual field. It was found that for larger angles (>1degree) the functional effect corresponded precisely to the effect of a light with a luminosity equal to that of the light that is perceived spreading around such a bright source. This perceived spreading of light was called straylight and by international standard disability glare was defined as identical to straylight. The phenomenon was recognized in the ophthalmological community as an important aspect of the quality of vision and attempts were made to design instruments to measure it. This must not be confused with instruments that assess light spreading over small distances (<1 degree), as originating from (higher order) aberrations and defocus. In recent years a new instrument has gained acceptance (C-Quant) for objective and controllable assessment of straylight in the clinical setting. This overview provides a sketch of the historical development of straylight measurement, as well as the results of studies on the origins of straylight (or disability glare) in the normal eye, and on findings on cataract (surgery) and corneal conditions.  相似文献   
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Background: The United States Food and Drug Administration banned the stimulant 1,3-dimethylamylamine (1,3-DMAA) from dietary supplements and warned consumers that the stimulant can pose cardiovascular risks ranging from high blood pressure to heart attacks.

Objectives: We designed our study to determine if a new stimulant similar in structure to 1,3-DMAA has been introduced as an ingredient in supplements sold in the United States (US).

Methods: We analyzed six brands of supplements that listed an ingredient on the label (e.g., Aconitum kusnezoffii, DMHA or 2-amino-isoheptane) that might refer to an analog of 1,3-DMAA. Supplements were analyzed by two separate laboratories using ultra-high-performance liquid chromatography mass spectrometry and reference standards.

Results: Two previously unidentified 1,3-DMAA analogs (2-amino-6-methylheptane [octodrine] and 1,4-dimethylamylamine [1,4-DMAA]) and two banned stimulants (1,3-DMAA and 1,3-dimethylbutylamine [1,3-DMBA]) were identified. Octodrine was found at a dose (±95% CI) of 72?±?7.5?mg per serving. In Europe, octodrine was previously sold as a pharmaceutical in multi-ingredient medications at dosages from 8 to 33?mg. The quantity of octodrine found in our study was more than twice the largest pharmaceutical dose. The other new stimulant, 1,4-DMAA, has not previously been approved for human consumption, and its safety in humans is unknown. 1,4-DMAA was found at dosages between 21?±?11?mg to 94?±?48?mg per serving. In addition, two banned stimulants – 1,3-DMAA and 1,3-DMBA – were also identified: 24?±?7.6?mg to 35?±?11?mg of 1,3-DMAA and 51?±?16?mg of 1,3-DMBA. In one product, 24?±?7.6?mg of 1,3-DMAA was combined with 21?±?11?mg of 1,4-DMAA. 1,3-DMAA has been investigated as potentially contributing to hemorrhagic strokes and sudden death, whereas the safety of 1,3-DMBA in humans is unknown.

Conclusion: Two banned stimulants (1,3-DMAA and 1,3-DMBA) and two previously unidentified stimulants (1,4-DMAA and octodrine) were identified in supplements sold in the United States.  相似文献   
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OBJECTIVES: To compare the risk of mortality of nonagenarian siblings with that of sporadic nonagenarians (not selected on having a nonagenarian sibling) and to compare the prevalence of morbidity in their offspring with that of the offsprings' partners.
DESIGN: Longitudinal (mortality risk) and cross-sectional (disease prevalence).
SETTING: Nationwide sample.
PARTICIPANTS: The Leiden Longevity Study consists of 991 nonagenarian siblings derived from 420 Caucasian families, 1,365 of their offspring, and 621 of the offsprings' partners. In the Leiden 85-plus Study, 599 subjects aged 85 were included, of whom 275 attained the age of 90 (sporadic nonagenarians).
MEASUREMENTS: All nonagenarian siblings and sporadic nonagenarians were followed for mortality (with a mean±standard deviation follow-up time of 2.7±1.4 years and 3.0±1.5 years, respectively). Information on medical history and medication use was collected for offspring and their partners.
RESULTS: Nonagenarian siblings had a 41% lower risk of mortality ( P <.001) than sporadic nonagenarians. The offspring of nonagenarian siblings had a lower prevalence of myocardial infarction (2.4% vs 4.1%, P =.03), hypertension (23.0% vs 27.5%, P =.01), diabetes mellitus (4.4% vs 7.6%, P =.004), and use of cardiovascular medication (23.0% vs 28.9%, P =.003) than their partners.
CONCLUSION: The lower mortality rate of nonagenarian siblings and lower prevalence of morbidity in their middle-aged offspring reinforce the notion that resilience against disease and death have similar underlying biology that is determined by genetic or familial factors.  相似文献   
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Hyperpolarized (HP) 3He magnetic resonance imaging has been recently used to produce high‐resolution images of pulmonary ventilation after methacholine (MCh) challenge in mouse models of allergic inflammation. This capability presents an opportunity to gain new insights about these models and to more sensitively evaluate new drug treatments in the pre‐clinical setting. In the current study, we present our initial experience using two‐dimensional (2D), time‐resolved 3He MRI of MCh challenge‐induced airways hyperreactivity (AHR) to compare ovalbumin‐sensitized and challenged (N = 8) mice to controls (N = 8). Imaging demonstrated that ovalbumin‐sensitized and challenged animals exhibited many large ventilation defects even prior to MCh challenge (four out of eight) compared to no defects in the control animals. Additionally, the ovalbumin‐sensitized and challenged animals experienced a greater number of ventilation defects (4.5 ± 0.4) following MCh infusion than did controls (3.3 ± 0.6). However, due to variability in MCh delivery that was specific to the small animal MRI environment, the difference in mean defect number was not statistically significant. These findings are reviewed in detail and a comprehensive solution to the variability problem is presented that has greatly enhanced the magnitude and reproducibility of the MCh response. This has permitted us to develop a new imaging protocol consisting of a baseline 3D image, a time‐resolved 2D series during MCh challenge, and a post‐MCh 3D image that reveals persistent ventilation defects. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
20.
Lesch‐Nyhan disease (LND) is characterized by dystonia, cognitive abnormalities, and self‐injurious behavior. No effective therapies are available. LND is associated with a presynaptic dopaminergic deficit, but the reported effects of dopamine replacement therapy are conflicting. The current prospective open‐label study assesses the effects of levodopa on both neurological and behavioral features of LND. All 6 study participants discontinued levodopa early, due to lack of effect and sometimes worsening of motor function. The results provide important clues for pathophysiological mechanisms and suggestions for future treatment options. © 2011 Movement Disorder Society  相似文献   
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