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991.

Objective

The aim of this study was to evaluate long-term fatigue behavior using an in vitro step-stress accelerated life test (SSALT), and to determine the crack initiation point using in silico finite element analysis for computer-aided designed and manufactured (CAD/CAM) molar crowns fabricated from three commercial CAD/CAM resin composite blocks: Cerasmart (CS; GC, Tokyo, Japan), Katana Avencia Block (KA; Kuraray Noritake Dental, Niigata, Japan), and Shofu Block HC (HC; Shofu, Kyoto, Japan).

Methods

Fifty-one mandibular first molar crowns luted on a resin core die were embedded in acrylic resin and covered with a polyvinyl chloride tube. Single compressive tests were performed for five crowns. SSALT was conducted for 36 crowns using three profiles and reliabilities at 120,000 cycles, and a Weibull analysis was conducted. The maximum principal strain of each CAD/CAM resin composite crown model was analyzed by three-dimensional finite element analysis.

Results

Fracture loads of CS and KA (3784 ± 144 N and 3915 ± 313 N) were significantly greater than that of HC (2767 ± 227 N) (p < 0.05). Fracture probabilities at 120,000 cycles were 24.6% (CS), 13.7% (KA), and 14.0% (HC). Maximum principal strain was observed around the mesiolingual cusps of CS and KA and the distobuccal cusp of HC.

Significance

CAD/CAM resin composite molar crowns containing nano-fillers with a higher fraction of resin matrix exhibited higher fracture loads and greater longevity, suggesting that these crowns could be used as an alternative to ceramic crowns in terms of fatigue behavior.  相似文献   
992.
To date, the association between diabetes mellitus (DM) and gastric cancer has been controversial, including the underlying mechanism. We investigated the association between plasma diabetic biomarkers (insulin, C‐peptide, and blood glucose) and gastric cancer risk. In addition, homeostasis model assessment of insulin resistance (HOMA‐IR) and homeostasis model assessment of β‐cell function (HOMA‐β) were calculated. A total of 36,745 subjects aged 40–69 years in the Japan Public Health Center‐based prospective study (JPHC) who returned the baseline questionnaire and provided blood samples were followed from 1990 to 2004. In the present analysis, 477 cases and 477 matched controls were used. The odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) for developing gastric cancer were calculated using conditional logistic regression models. Plasma insulin was positively associated with increased risk of gastric cancer; compared to tertile 1, ORs were 1.69 (95% CI = 1.11–2.59) and 2.01 (1.19–3.38) for tertiles 2 and 3, respectively (p for trend = 0.009). In men, C‐peptide was also positively associated with a significant risk; corresponding ORs were 1.42 (0.85–2.38) and 1.91 (1.03–3.54), respectively (p for trend = 0.04). These findings were confirmed for blood samples from the fasting group (≥8 hr after a meal). Higher HOMA‐IR was also associated with increased risk, whereas no association was observed for blood glucose. Our findings suggest that Japanese population with higher insulin and C‐peptide levels derived from insulin resistance have an elevated risk of gastric cancer.  相似文献   
993.
994.
ObjectiveThe hepatocyte low density lipoprotein receptor (LDLR) plays a pivotal role in lipoprotein metabolism by lowering plasma LDL-cholesterol, a risk factor for atherosclerosis. The present study was conducted to investigate the effects of grape polyphenols on LDLR gene expression in human hepatocyte models.Methods and resultsAmong the 14 phenolic compounds in red wine, we found that a stilbene trans-resveratrol most strongly up-regulated LDLR gene expression in HepG2 cells. Trans-resveratrol increased the LDLR protein and uptake of fluorescent-labeled LDL. Moreover, it enhanced LDLR gene promoter activity through the proteolytic activation of the sterol regulatory element-binding protein-2 (SREBP-2) as well as SREBP-1. However, sterols completely abolished trans-resveratrol-induced SREBP activation and LDLR gene expression. Finally, AMP-activated protein kinase (AMPK) knockdown analyses by siRNA revealed that AMPK activation was unnecessary for the effects of trans-resveratrol.ConclusionsTrans-resveratrol up-regulated hepatic LDLR expression via proteolytic activation of SREBPs. We concluded that trans-resveratrol exhibits the anti-atherogenic effect, at least in part, by increased hepatic LDLR expression and subsequent LDL uptake.  相似文献   
995.
Marked splenomegaly as the main presenting sign in follicular lymphoma (FL) is rare. The clinical and morphologic findings of 3 FL patients with massive splenomegaly and slight or no lymphadenopathy are presented. All cases had massive splenomegaly, and 2 had minimal peripheral lymphadenopathy with bone marrow infiltration, which is the major involved site besides the spleen. Histologically, various sizes of micronodules, composed of medium-sized centrocytes, were present in the white pulp in 2 cases in whom splenectomy was performed. The other case was complicated by nephrotic syndrome and showed aggregates of packed small lymphocytes in the spleen and renal parenchyma. Tumor cells were positive for CD10, CD20, bcl-2, and bcl-6. Since these cases are clinically similar to splenic marginal zone lymphoma, recognition of this disease and selection of the appropriate therapy are needed.  相似文献   
996.
Epidemiological research into insulin resistance has focused on excess body weight, type 2 diabetes mellitus (DM), physical activity, and coffee consumption. These common modifiable factors have also been suggested to play a role in the process of carcinogenesis via associations with insulin resistance. Findings of systematic literature reviews and meta-analyses have generally supported an association between excess body weight and DM with an increased risk of colon cancer in males, and of liver, pancreatic, and endometrial cancers. Inverse relationships between these cancers and physical activity and coffee consumption have been shown, both of which are known to reduce the risk of DM. Interventions directed at or involving these variables should contribute to decreasing the risk of insulin resistance-associated cancer.  相似文献   
997.
Aim: To examine the impact of C-reactive protein on the risks of stroke and its subtypes, particularly among Asian populations in which median C-reactive protein levels are typically lower than in Western populations.Methods: A prospective, nested case-control study was conducted to examine the associations between high sensitivity-CRP (hs-CRP) and risks of cardiovascular disease within a cohort of 29,876 men and women aged 40-69 years, with no history of stroke, ischemic heart disease or cancer, who submitted blood samples between 1990 and 1993. Systematic cardiovascular surveillance was performed throughout 2007. One control for each stroke and two controls for each ischemic heart disease were matched for sex, age, date of blood drawing, time since last meal and study location.Results: We documented 1,132 incident strokes (638 ischemic and 494 hemorrhagic strokes) and 209 ischemic heart diseases (168 myocardial infarctions and 41 sudden cardiac deaths), and observed a linear association between hs-CRP levels and risks of ischemic stroke and ischemic heart disease, more specifically myocardial infarction. The multivariable odds ratios associated with 1-SD increment of logarithmically transformed hs-CRP were 1.13 (0.99-1.29),p= 0.07 for ischemic stroke, 1.16 (0.96-1.41),p= 0.13 for lacunar infarction, 1.41 (0.98-2.01),p= 0.06 for embolic infarction, and 1.28 (1.03-1.59),p= 0.03 for myocardial infarction. The predictive value of hs-CRP for ischemic stroke was reduced primarily after adjustment for hypertensive status and body mass index. No association was found between hs-CRP levels and the risk of hemorrhagic or total stroke.Conclusions: High serum hs-CRP levels were associated with the risk of myocardial infarction and more weakly with the risk of ischemic stroke among middle-aged Japanese men and women.  相似文献   
998.
Cushing's syndrome is extremely rare during pregnancy, because it often causes amenorrhea and infertility. We experienced a case of Cushing's syndrome in the 23rd week of pregnancy receiving laparoscopic surgery. It was difficult to control the blood pressure and heart rate, but we succeeded in the safe management of both mother and fetus.  相似文献   
999.
Solitary fibrous tumor of pleura (SFTP) is a rare mesenchymal neoplasm that most commonly involves the pleura, is probably derived from fibroblasts, and has no relationship to malignant mesothelioma. Here, we report a case of complete resection of a giant malignant SFTP. A 61-year-old woman developed fever and left flank pain. Computed tomography revealed the tumor to be 13?cm in size and located in the left thoracic cavity, directly invading the left lower lobe of the lung. The patient underwent radical resection and left lower lobectomy. Immunohistochemical examination revealed a dense proliferation of spindle-shaped cells with ovoid nuclei and collagen fibers hyperplasia. The cells were positive for CD34 and vimentin, and were negative for cytokeratin AE1/AE3, calretinin, S-100 and smooth muscle ??-actin. SFTPs have malignant potential, as 20?C30?% of resected SFTPs reportedly contain malignant components. Careful long-term clinical follow-up is therefore required for all cases of SFTP.  相似文献   
1000.
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