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41.
Dyschromatosis symmetrica hereditaria (DSH) is a pigmentary genodermatosis of autosomal dominant inheritance caused by a mutation of adenosine deaminase acting on the RNA 1 gene (ADAR1). It is characterized by a mixture of hyper‐ and hypopigmented macules on the back of the hands and feet. The pathomechanism by which the ADAR1 gene mutation induces DSH has not been clarified yet. We experienced an 11‐year‐old male DSH patient associated with dystonia, mental deterioration and brain calcification, who had a mutation of p.G1007R in the ADAR1 gene. This mutation had already been reported in a patient with similar neurological symptoms by Tojo et al. Additionally, a patient with DSH associated with torsion dystonia was reported by Patrizi et al., but gene analysis was not carried out. Only three cases with neurological disorders have been reported, although more than 50 mutations of the ADAR1 gene causing DSH have been reported and none of them had any neurological symptoms. Therefore, we suggest that neurological disorders rarely develop in DSH.  相似文献   
42.
Summary  This study was conducted to evaluate the effect of polyphosphoric acid (PPA) treatment on bone regeneration around titanium (Ti) implants in vivo . Adsorption of PPA by Ti was achieved by immersing Ti implants (2 mm in diameter, 4 mm in length) in different concentrations of PPA solution (0, 1 and 10 wt%) for 24 h at 37 °C after proper Ti surface cleaning. The treated Ti implants were implanted on 8-week-old-male rat ( n  = 30) tibiae. Two or four weeks after implantation, all animals were deeply anaesthetized and underwent perfusion fixation. Ten specimens in each condition were further immersed in the same fixative for 1 week and eventually embedded in polyester resin. Afterwards, undecalcified sections were ground to a thickness of approximately 70 μm parallel to the long axis of the implant. The sections were stained with basic fuchsine and methylene blue and then examined by light microscopy. For quantitative evaluation of bone regeneration around the implants, the bone-implant contact ratio (BICR) was determined. Polyphosphoric acid treatment of the Ti implant surface significantly enhanced direct bone contact to the Ti surface. Especially, the BICRs of the 1 wt% PPA-treated Ti implants were significantly higher than those of the control untreated Ti implants, both 2 and 4 weeks after implantation. At 4 weeks, 10 wt% PPA-treated implants also significantly increased the BICR as compared to that of the untreated Ti implants. These results suggest that PPA treatment promotes osteoconductivity of Ti in vivo .  相似文献   
43.
Introduction: We examined whether quantification of T-wave alternans (TWA) enhances this parameter's capacity to evaluate the risk for total and cardiovascular mortality and sudden cardiac death (SCD).
Methods and Results: The Finnish Cardiovascular Study (FINCAVAS) enrolled consecutive patients (n = 2,119; 1,342 men and 777 women) with a clinically indicated exercise test with bicycle ergometer. TWA (time domain-modified moving average method) was analyzed from precordial leads, and the results were grouped in increments of 10 μV. Hazard ratios (HR) for total and cardiovascular mortality and SCD were estimated for preexercise, routine exercise, and postexercise stages. Cox regression analysis was performed. During follow-up of 47.1 ± 12.9 months (mean ± standard deviation [SD]), 126 patients died: 62 were cardiovascular deaths, and 33 of these deaths were sudden. During preexercise, TWA ≥ 20 μV predicted the risk for total and cardiovascular mortality (maximum HR >4.4 at 60 μV, P < 0.02 for both). During exercise, HRs of total and cardiovascular mortality were significant when TWA measured ≥50 μV, with 90 μV TWA yielding maximum HRs for total and cardiovascular death of 3.1 (P = 0.03) and 6.4 (P = 0.002), respectively. During postexercise, TWA ≥60 μV indicated risk for total and cardiovascular mortality, with maximum HR of 3.4 at 70 μV (P = 0.01) for cardiovascular mortality. SCD was strongly predicted by TWA levels ≥60 μV during exercise, with maximum HR of 4.6 at 60 μV (P = 0.002), but was not predicted during pre- or postexercise.
Conclusion: Quantification of TWA enhances its capacity for determination of the risk for total and cardiovascular mortality and SCD in low-risk populations. Its prognostic power is superior during exercise compared to preexercise or postexercise.  相似文献   
44.
A pacemaker lead fracture in the left subclavian vein was caused by compression of the clavicle and the first rib; subsequent coil elongation at the same site on the right side was observed in the replacement lead in a patient with thoracic outlet syndrome. Venography showed narrowing of the subclavian vein at the site where the lead abnormalities were observed. This case illustrates that a lead in the subclavian vein can be easily damaged when a patient has thoracic outlet syndrome.  相似文献   
45.
46.
In the past 4 years, 34 asymptomatic patients with the Wolff-Parkinson-White (WPW) pattern underwent electrophysiologic study. The effective refractory period (ERP) of antegrade conduction over the accessory pathway was 288 +/- 29 msec. In three asymptomatic patients (9%), the antegrade ERP of the accessory pathway was shorter than 250 msec. The antegrade ERP of the accessory pathway became shorter than 250 msec in an additional 12 of 22 (55%) patients after isoproterenol administration. Nineteen (56%) of the asymptomatic patients showed the absence of retrograde conduction over the accessory pathway even after isoproterenol administration. The rate of induction of orthodromic reciprocating tachycardia in the asymptomatic WPW patients was 15% (5/34), which was significantly lower than that in the symptomatic patients. These data suggest that in the asymptomatic patients, the absence of retrograde conduction over the accessory pathway is the reason they remained asymptomatic, free of reciprocating tachycardia. However, even in the asymptomatic patients, some had the accessory pathway in which antegrade ERP was shorter than 250 msec. They may result in rapid ventricular conduction over the accessory pathway when atrial fibrillation develops.  相似文献   
47.
Background and objective: The aim of the present study was to examine clinical and other features that might allow prognostic distinctions between histological patterns in presentations with rapidly progressive interstitial pneumonia (RPIP), and to assess prognostic factors for survival. Methods: Patients with RPIP among 425 consecutive patients with diffuse lung disease, who underwent surgical lung biopsy, were studied retrospectively. The discriminatory value of clinical and investigative features for identifying disease with a better outcome was evaluated. An a priori comparison was made between diffuse alveolar damage (DAD)/usual interstitial pneumonia with DAD pattern (Group A), and organizing pneumonia/non‐specific interstitial pneumonia pattern (Group B). Results: Twenty‐eight patients (6.6%) fulfilled the criteria for RPIP. The diagnosis was Group A disease in 15 (DAD in 10, usual interstitial pneumonia with DAD in 5), and Group B disease in 13 (organizing pneumonia in 8, non‐specific interstitial pneumonia in 5). There were no significant differences in initial findings between the groups. Prognosis was significantly better for Group B patients than for Group A patients (P = 0.021). Neither BAL nor parenchymal high‐resolution CT score was indicative of therapeutic responsiveness or outcome. Distinction between Group A and Group B on the basis of disease pattern was the only significant determinant of prognosis. Conclusions: RPIP included varied histological patterns with different outcomes, and in many cases these could not be predicted using baseline clinical data. Histology was the only significant predictor of ultimate prognosis.  相似文献   
48.
Background: Depression may increase the risk of developing Alzheimer's disease (AD). Recent large cohort studies have also shown that a low plasma amyloid β (Aβ)‐42 level combined with a high Aβ40 level increases the risk of developing AD, suggesting plasma Aβ42/40 ratio as useful for identifying risk of developing mild cognitive impairment and AD. Although several studies have examined Aβ levels in the peripheral blood of elderly individuals with depression, results have been inconsistent. Furthermore, no results have been described for younger depression. Methods: Serum Aβ40, Aβ42 level and Aβ40/42 ratio were evaluated using enzyme‐linked immunosorbent assay in 60 patients with major depressive disorder (MDD) and 60 healthy controls. The results were analyzed in two age groups (young, <60 years; elderly, ≥60 years). Results: Serum Aβ40 level was significantly higher in young MDD patients compared to young controls (P < 0.001), but it was not significantly deferent in the elderly group. Serum Aβ42 level did not differ significantly in both young and elderly groups. Aβ40/42 ratio was significantly higher in both young (P < 0.001) and elderly (P < 0.001) patients with MDD compared to controls. Conclusions: Serum Aβ40/42 ratio was significantly higher in MDD patients than in controls, and this difference was seen for both elderly and young subjects. This may suggest that even young subjects with MDD undergo pathological changes in the very early stage of amyloid deposition.  相似文献   
49.
Saw palmetto extract (SPE), an extract from the ripe berries of the American dwarf palm, has been widely used as a therapeutic remedy for urinary dysfunction due to benign prostatic hyperplasia (BPH) in Europe. Numerous mechanisms of action have been proposed for SPE, including the inhibition of 5a-reductase. Today, al-adrenoceptor antagonists and muscarinic cholinoceptor antagonists are commonly used in the treatment of men with voiding symptoms secondary to BPH. The improvement of voiding symptoms in patients taking SPE may arise from its binding to pharmacologically relevant receptors in the lower urinary tract, such as al-adrenoceptors, muscarinic cholinoceptors, 1,4-dihyropyridine receptors and vanilloid receptors. Furthermore, oral administration of SPE has been shown to attenuate the up-regulation of α1-adrenoceptors in the rat prostate induced by testosterone. Thus, SPE at clinically relevant doses may exert a direct effect on the pharmacological receptors in the lower urinary tract, thereby improving urinary dysfunction in patients with BPH and an overactive bladder. SPE does not have interactions with co-administered drugs or serious adverse events in blood biochemical parameters, suggestive of its relative safety, even with long-term intake. Clinical trials (placebo-controlled and active-controlled trials) of SPE conducted in men with BPH were also reviewed. This review should contribute to the understanding of the pharmacological effects of SPE in the treatment of patients with BPH and associated lower urinary tract symptoms (LUTS).  相似文献   
50.
目的辅助性T细胞17(Th17)是-种CD4阳性T细胞新亚群,本研究探讨Th17相关细胞因子与根尖周炎的炎症反应及牙槽骨破坏的关系。方法选取5周龄雄性Wistar大鼠,实验组用球钻将下颌第1磨牙开髓,根管锉清理牙髓,髓腔暴露于口腔中,14d后断颈处死。以未开髓的上颌第1磨牙作为对照组。取上下颌骨,采用Micro—CT观察根尖病损的形成情况;实验组和对照组标本均为6例,标本固定、脱钙,冰冻切片、组织学方法观察根尖病损的特点,采用抗CD68和抗TCRαβ的单克隆抗体进行免疫组化;用酶组织化学染色(TRAP染色)进行破骨细胞染色;实验组和对照组根尖组织提取总RNA,RT-PCR及荧光实时定量PCR方法定量检测根尖组织中Th17相关细胞因子IL-17、IL-23、IL-β、IL-6、TGF—β,以及破骨细胞分化因子RANKL的mRNA表达情况。结果Micro.CT显示,14d实验组有明显的根尖病损形成;组织学结果表明,实验组均存在根尖脓肿,有大量中性粒细胞、CD68阳性的巨噬细胞和散在的TCRctl3阳性T细胞浸润;病损骨面有较多的TRAP阳性破骨细胞,表明有活跃的骨吸收;RT—PCR及实时定量PCR结果显示,实验组根尖组织中Th17相关细胞因子IL-17、IL-23、IL1β、IL-6,及破骨细胞分化因子RANKL的mRNA均显著高于对照组,而TGF-β无显著性变化。结论Th17相关细胞因子在实验性根尖周炎中均有高表达,提示它们可能参与炎症过程和骨破坏。  相似文献   
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