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The aim of this randomized double-blind, clinical trial was to compare the use of enamel matrix derivative (EMD) and demineralised freeze-dried bone allografts (DFDBA) with DFDBA alone for the treatment of human periodontal intrabony defects at 12 months post-surgery. Fifty-six intrabony osseous defects in 56 periodontis patients were randomly assigned to the test group (DFDBA + EMD) or the control group (DFDBA) for periodontal treatment. Clinical and radiographic measurements were made at the baseline and after 12 months. Compared to baseline, the 12-month results indicated that both treatment modalities resulted in significant changes in all clinical parameters (gingival index, bleeding on probing, probing depth (PD), clinical attachment level (CAL), gingival recession; P < 0.05) and radiographic parameters (hard tissue fill (HTF) and bone depth reduction; P < 0.05). Furthermore, statistically significant differences were found in the test group compared to the control group in PD reduction (5.0 mm vs. 4.0 mm; P < 0.05), CAL gain (4.0 mm vs. 3.25 mm), and HTF (4.0 mm vs. 3.5 mm; P < 0.05). In the test group, 25% of sites gained >4 mm of CAL, while in the control group, 7.1% of sites gained >4 mm of CAL. Both treatments showed a good soft and hard periodontal tissue response. At 12 months post-surgery, the combined use of DFDBA and EMD seemed to produce a statistically significant improvement of PD reduction, CAL gain, and HTF.  相似文献   
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A 66-year-old man with multiple comorbidities presented with a juxtarenal perianastomotic aortic aneurysm 10 years after open abdominal aortic aneurysm repair. The aneurysmal disease also involved both iliac bifurcations, the right internal iliac artery, the left common femoral artery (CFA) up to its bifurcation, and the homolateral popliteal artery. We performed bilateral internal iliac artery coil embolization 1-month apart. Later, we performed aortouniiliac endografting extending to the right external iliac artery and placement of an endovascular plug in the left external iliac artery. A right CFA to left femoral bifurcation bypass graft was then constructed after ligation of the left CFA aneurysm. After recovering from anesthesia and despite sequential hypogastric embolization, the patient developed postoperative paraplegia, buttock ischemia, and ischemic colitis and died on postoperative day 5. The possible pathogenic mechanisms involved in the onset of these ischemic complications are discussed in this article.  相似文献   
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In the elderly, the most common cause of dementia is Alzheimer disease (AD), which is responsible for the age-related progressive neurodegenerative inflammatory condition mediated by the disease. It has been seen that several genetic and environmental factors are involved in AD onset. Epidemiologic data suggest that some genetic determinants of AD might reside in those polymorphisms that regulate immune inflammatory responses, such as the major histocompatibility complex (MHC). Therefore, several MHC polymorphisms have been in the spotlight of a large number of AD association studies. A possible association of HLA-A2 allele with increased susceptibility to AD has been the subject of debate for more than 20 years, even if the results of these studies, in the various populations, are discordant. Thus, to gain insight in this matter, the authors have studied the HLA-A2 allele for a possible association with sporadic AD in a homogeneous population of Italian patients. For this reason, the distribution of HLA-A2 allele in patients with sporadic AD and controls was analyzed by PCR-SSP assay. The results demonstrated a significant difference in the frequency of HLA-A2 allele between patients with sporadic AD and controls (46% versus 38%). Thus, these data confirm a positive role of HLA-A2 allele in the risk of developing AD. However, some of the observed discrepancies may result from clinical or genetic heterogeneity of the populations under study or methodologic biases. Besides, whenever external agents such as viruses play a role, these might different in the various populations leading to various associations. However, it has to be taken into account that there are many molecular HLA-A2 subtypes with different frequencies in various populations. Therefore, further studies should include molecular typing of HLA-A2 subtypes.  相似文献   
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Alzheimer disease (AD) is the most common form of dementia with complex etiology and multifactorial origin. Although several neurochemical deficits have been described in AD patients, explanation of the nature of the cognitive disturbance is focused on the "cholinergic hypothesis." The neuronal nicotinic acetylcholine receptor (neuronal nAChR) belongs to the superfamily of ionic channel activated by ligand. This paper presents a population-based population association study, testing the hypothesis that variants of the nAChR gene confer genetic susceptibility to AD. The authors analyzed two cohorts constituted by 60 controls and 80 AD patients in which significant increase of 594T polymorphism in patients affected by AD versus controls was found. However, further studies are necessary to confirm this polymorphism trend and to establish the polymorphism functionality and its correlation with behavioral and cognitive deficit.  相似文献   
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