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931.
AimsMounting data support a ‘calcification paradox’, whereby reduced bone mineral density is associated with increased vascular calcification. Furthermore, reduced bone mineral density is prevalent in older persons with lower body mass index (BMI). Therefore, although BMI and coronary artery calcification (CAC) exhibit a positive relationship in younger persons, it is predicted that in older persons and/or those at risk for osteoporosis, an inverse relationship between BMI and CAC may apply. We sought to explore this hypothesis in a large group of patients with coronary artery disease undergoing percutaneous coronary intervention (PCI).Methods and resultsWe accessed our single-center registry for 07/01/1999 to 06/30/2009, extracting data on all patients that underwent PCI. To minimize bias we excluded those at the extremes of age or BMI and non-Black/Hispanic/Caucasians, leaving 9993 study subjects (age 66.6 ± 9.9 years). Index lesion calcification (ILC) was analyzed with respect to BMI. Comparing index lesions with no angiographic calcification to those with the most severe, mean BMI decreased by 1.11 kg m?2; a reduction of 3.9% (P < 0.0001). By multivariable modeling, BMI was an independent inverse predictor of moderate–severe ILC (m-sILC; odds ratio [OR] 0.967, 95% CI 0.953–0.980, P < 0.0001). Additional fully adjusted models identified that, compared to those with normal BMI, obese patients had an OR of 0.702 for m-sILC (95% CI 0.596–0.827, P < 0.0001).ConclusionsIn a large group of PCI patients, we identified an inverse correlation between BMI and index lesion calcification. These associations are consistent with established paradigms and suggest a complex interrelationship between BMI, body size and vascular calcification.  相似文献   
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Purpose: To document the outcome of single implants in the anterior maxilla following four routine treatment modalities when performed by experienced clinicians in daily practice using the same implant system and biomaterials. Material and Methods: A retrospective study in patients who had been treated by two periodontists and two prosthodontists in 2006 and 2007 was conducted. The four treatment modalities practically covered every clinical situation and included standard implant treatment (SIT), immediate implant treatment (IIT), implant treatment in conjunction with guided bone regeneration (GBR), and implant treatment in grafted bone (BGR) harvested from the chin. All implants were installed via flap surgery. Patients were clinically and radiographically examined. Complications were registered and the aesthetic outcome (pink esthetic score [PES] and white esthetic score [WES]) was rated. A blinded clinician who had not been involved in the treatment performed all evaluations. Patient's aesthetic satisfaction was also registered. Results: One hundred four out of 115 eligible patients (44 SIT, 28 IIT, 18 GBR, and 14 BGR) received at least one single NobelReplace tapered TiUnite® (Nobel Biocare, Göteborg, Sweden) implant in the anterior maxilla and were available for evaluation. Clinical parameters (implant survival: 93%, mean plaque level: 24%, mean bleeding on probing: 33%, and mean probing depth: 3.2 mm) and mean bone level (1.19 mm) did not differ significantly between treatment modalities. Postoperative complications were more common following GBR/BGR (>61%) when compared with SIT/IIT (<18%) (p < .001). BGR was in 4/14 patients associated with permanent sensory complications at the donor site. Technical complications occurred in 9/104 patients. SIT and IIT showed similar soft tissue aesthetics (PES: 10.07 and 10.88, respectively), however major alveolar process deficiency was common (>15%). PES was 9.65 for GBR. BGR showed inferior soft tissue aesthetics (PES: 9.00; p = .045) and shorter distal papillae were found following GBR/BGR (p = .009). Periodontal disease (odds ratio [OR]: 13.0, p < .001), GBR/BGR (OR: 4.3, p = .004), and a thin‐scalloped gingival biotype (OR: 3.7, p = .011) increased the risk for incomplete distal papillae. WES was 7.98 for all patients considered. Poor agreement was found between objective and subjective aesthetic ratings. Conclusions: All treatment modalities were predictable from a clinical and radiographic point of view. However, advanced reconstructive surgery, especially BGR, increased the risk for complications and compromised aesthetics. Research is required on the prevention and minimally invasive treatment of buccal bone defects at the time of tooth loss to avoid complex therapy.  相似文献   
936.
Immunological factors are important in pathogenesis of various malignancies, including neural cancers. The CXC chemokine CXCL12 is involved in the immune responses. Therefore, the aim of the present study was to investigate the association between tumor tissue and circulating concentrations of CXCL12 as well as its genetic variation at position +801 known as(the SDF-1 3'A), in Iranian patients suffering from malignant glial tumors. In this study, stereotactic tumor biopsy specimens in parallel with peripheral blood samples were collected from 123 patients and 189 healthy controls. The serum level of CXCL12 was measured by ELISA and tumor tissues were subjected to Western blotting for intra-tumor CXCL12 detection; we also employed PCR-RFLP to detect the SDF-1 3'A polymorphism. Demographic data were collected by a researcher-designed questionnaire. These results demonstrated a significant difference between the A/A, A/G, and G/G genotype and A and G alleles of polymorphisms at position +801 of CXCL12. We also indicated elevated levels of CXCL12 in circulation and tumor tissue obtained from in patients suffering from malignant glial tumors. Based upon the results of this investigation, we propose that CXCL12 and its SDF-1 3'A polymorphism play a fundamental part in the pathogenesis of malignant glial tumors. It is also noteworthy that CXCL12 could probably be utilized as a beneficial biological marker in the diagnosis of these tumors.  相似文献   
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ObjectiveIn non-invasive somatotopic mapping based on neuromagnetic source analysis, the recording time can be shortened and accuracy improved by applying simultaneously vibrotactile stimuli at different frequencies to multiple body sites and recording multiple steady-state responses. This study compared the reliability of sensory evoked responses, source localization performance, and reproducibility of digit maps for three different stimulation paradigms.MethodsVibrotactile stimuli were applied to the fingertip and neuromagnetic steady-state responses were recorded. Index and middle fingers were stimulated either sequentially in separate blocks, simultaneously at different frequencies, or in alternating temporal order within a block.ResultsResponse amplitudes were largest and source localization was most accurate between 21 and 23 Hz. Separation of adjacent digits was significant for all paradigms in all participants. Suppressive interactions occurred between simultaneously applied stimuli. However, when frequently alternating between stimulus sites, the higher stimulus novelty resulted in increased amplitudes and superior localization performance.ConclusionsWhen receptive fields are strongly overlapping, the alternating stimulation is preferable over recording multiple steady state responses.SignificanceThe new paradigm improved the measurement of the distance of somatotopic finger representation in human primary somatosensory cortex, which is an important metric for neuroplastic reorganization after learning and rehabilitation training.  相似文献   
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