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PURPOSE: This study aimed to evaluate the clinical success of a hydrophilic polyvinyl siloxane impression material for fixed dental restorations under various clinical conditions. MATERIALS AND METHODS: A total of 1,466 preparations for fixed restorations in maxillary and mandibular anterior and posterior teeth were evaluated. The study contained inlay, onlay, crown, veneer, post, and adhesive-wing preparations and implants for gold, porcelain-fused-to-metal, and ceramic restorations. The preparation finish line relative to the crest of the marginal gingiva, type of restoration, and position of the teeth were recorded. Three categories were established to rate impression quality: perfect impressions, with an absence of any voids or bubbles and perfect reproduction of the preparation finish line, were rated Criteria I; acceptable impressions, with minimal defects (< or = 2 mm) not involving the preparation finish line, were rated Criteria II; and unacceptable impressions, with larger voids or bubbles (> 2 mm) or defects involving the preparation finish line, were rated Criteria III. RESULTS: Overall, 96.86% of the final impressions were clinically acceptable, 89.43% of which were rated Criteria I and 7.43% of which were rated Criteria II. Only 3.14% of the impressions were unacceptable and rated Criteria III. A significant influence on impression quality was found when the preparation finish line was more than 2 mm subgingival (P < .004), as well as when a beveled preparation was used (P < .004). The position of the teeth (P > .404) had no significant effect. CONCLUSION: Surface-activated polyvinyl siloxane impression material offers high predictability to avoid bubbles and voids in the final impression.  相似文献   
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OBJECTIVE—To assess the efficacy and safety of sulphasalazine in reactive arthritis.
METHODS—Double blind placebo controlled trial of six months duration comparing sulphasalazine 2-3 g per day (n = 37) with matching placebo (n = 42) in adults with active reactive arthritis (age 19-57 years, median 34). Treatment response was evaluated once a month by changes in erythrocyte sedimentation rate (ESR), pain, peripheral arthritis, tender iliosacral joints, entesopathy, extra-articular manifestations, and working ability.
RESULTS—15 patients in the sulphasalazine group and eight in the placebo group withdrew from the study prematurely. Adverse events, primarily gastrointestinal, were the main reason for withdrawal in the actively treated group. Intention-to-treat analyses showed significant improvements over time in both groups in ESR, pain, and number of swollen joints (P < 0.01). Number of days on sick leave decreased significantly in the sulphasalazine group only (P < 0.01). No significant differences between the two groups were present after six months. Among the patients completing the trial according to protocol, persistent complete remission had occurred within two months in five (23%) of the actively treated, but in no placebo treated patients (P = 0.013).
CONCLUSIONS—Sulphasalazine seemed to improve only the very short term outcome of reactive arthritis. The possible beneficial effect of the drug should also be weighed against the risk of adverse events. Although these were mainly mild, almost 25% of the patients in the actively treated group gave up treatment for this reason.

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Visual neglect results from dysfunction within the spatial attention network. The structural connectivity in undamaged brain tissue in neglect has barely been investigated until now. In the present study, we explored the microstructural white matter characteristics of the contralesional hemisphere in relation to neglect severity and recovery in acute stroke patients. We compared age‐matched healthy subjects and three groups of acute stroke patients (9 ± 0.5 days after stroke): (i) patients with nonrecovered neglect (n = 12); (ii) patients with rapid recovery from initial neglect (within the first week post‐stroke, n = 7), (iii) stroke patients without neglect (n = 17). We analyzed the differences between groups in grey and white matter density and fractional anisotropy (FA) and used fiber tracking to identify the affected fibers. Patients with nonrecovered neglect differed from those with rapid recovery by FA‐reduction in the left inferior parietal lobe. Fibers passing through this region connect the left‐hemispheric analogues of the ventral attention system. Compared with healthy subjects, neglect patients with persisting neglect had FA‐reduction in the left superior parietal lobe, optic radiation, and left corpus callosum/cingulum. Fibers passing through these regions connect centers of the left dorsal attention system. FA‐reduction in the identified regions correlated with neglect severity. The study shows for the first time white matter changes within the spatial attention system remote from the lesion and correlating with the extent and persistence of neglect. The data support the concept of neglect as disintegration within the whole attention system and illustrate the dynamics of structural‐functional correlates in acute stroke. Hum Brain Mapp 35:4678–4692, 2014. © 2014 Wiley Periodicals, Inc .  相似文献   
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Purpose:To compare the retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), and optic nerve head (ONH) morphological parameters between obstructive sleep apnea (OSA) patients and age-matched controls using spectral domain optical coherence tomography (SD-OCT).Methods:This case control study was conducted in a multi-specialty tertiary care hospital from 2014 to 2016. Patients diagnosed to have OSA by overnight polysomnography were included in the study. Fifty eyes of 25 OSA patients with clinically normal optic disc were compared with 50 eyes of age-matched controls. The study population underwent detailed ophthalmological evaluation including SD-OCT.Results:There was significant thinning of the superior, inferior, and average RNFL in the OSA group when compared to controls. GCL analysis also showed a significant thinning of the six sectors as well as average and minimum ganglion cell layer + inner plexiform layer in OSA patients. The optic nerve head rim area was significantly decreased in OSA patients when compared to controls.Conclusion:OSA patients even with clinically normal optic disc showed significant decrease in the RNFL thickness, GCL thickness, and rim area when compared to age-matched controls. Hence, these patients constitute a high-risk population who need to be regularly screened and followed up for ocular co-morbidities.  相似文献   
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目的探讨冈比亚按蚊中肠抗原抗媒介免疫的作用,进一步研究抗媒介疫苗抗原. 方法解剖室内饲养的冈比亚按蚊雌蚊中肠,立即置于冷的pH 7.4 PBS溶液中,用SDS-PAGE方法获得分子质量为43 ku中肠蛋白抗原,皮下注射免疫大白兔3次,获得的免疫血浆膜饲冈比亚按蚊成蚊,与对照组比较,观察其对冈比亚按蚊死亡率和生殖率的影响. 结果膜饲免疫血浆的冈比亚按蚊的死亡率与对照组相比显著增高,死亡率增加56%;生殖率明显下降,实验组蚊虫平均产卵率为71.4个,对照组为88.1个,下降18.7%. 结论采用有效的方法分离蚊媒中肠的关键性抗原-中肠蛋白抗原可能成为抗蚊媒和其它抗媒介疫苗的靶抗原.  相似文献   
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