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Metabolic Brain Disease - Recent evidence has shown that salmon calcitonin (sCT) has positive effects on the nervous system. However, its effect and mechanisms on glutamate-induced cytotoxicity are...  相似文献   
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This study investigated the value of Thiol/Disulfide homeostasis and ischemia-modified albumin (IMA) levels in discriminating diabetic cases with different stages of retinopathy and without retinopathy. In total, 122 patients with type 2 diabetes mellitus (DM) were enrolled in this prospective cross-sectional study. These patients were separated into three subgroups: Group 1 included 42 patients with DM and no diabetic retinopathy (DR), Group 2 included 40 patients with DM having non-proliferative DR and the Group 3 had 40 patients with DM having proliferative DR. The native thiol, total thiol, and disulfide levels and disulfide–native thiol, disulfide–total thiol, and native thiol–total thiol ratios as well as the IMA levels were analyzed and compared among the groups. There were no statistically significant differences regarding the ages and genders of the patients between the groups. The native thiol level, the total thiol level and the native thiol–total thiol ratio showed a statistically significantly reduction, while the disulfide level, the disulfide–native thiol ratio, and the disulfide–total thiol ratio showed a statistically significantly elevation in the Group 3 compared with the Group 1 and Group 2. Additionally, the mean IMA levels were statistically significantly higher in Group 3 when compared to Group 1 and Group 2 (p?=?.003 and p?=?.014, respectively). In conclusion, both Thiol/Disulfide homeostasis parameters and IMA levels increase with the progression of DR. Thiol/Disuldife homeostasis balance and IMA levels may be used a biomarker to monitor the tissue ischemia in DM and to discriminate the different stages of DR, in the future.  相似文献   
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Vitamin D is a secosteroid hormone that shares a synthetic pathway with cholesterol. ApoE, which is involved in the transport of cholesterol, is the most significant genetic risk factor for sporadic Alzheimer’s disease (AD). Surprisingly, recent studies have indicated the presence of an evolutionary juncture between these two molecules. To demonstrate this possible relationship, we investigated serum levels of 25-hydroxyvitamin-D3 (25OHD) in patients with early onset-AD (EOAD; n:22), late onset-AD (LOAD; n:72), mild cognitive impairment (MCI; n:32) and in healthy subjects (n:70). We then analyzed the correlation between 25OHD and cytokines, BDNF and Hsp90 with respect to ApoE alleles, as these molecules were investigated in our previous studies. The LOAD patients had low levels of 25OHD, but these low levels originated only from ApoE?4 non-carrier patients. Negative correlations were observed between serum 25OHD and TNFα, IL-1β or IL-6 levels in healthy subjects or MCI patients, but these same correlations were positive in LOAD patients. ApoE alleles indicated that these positive correlations exist only in ?4 carrier LOAD patients. Consequently, our results indicate that vitamin D deficiency presents a greater risk for ApoE?4 non-carrier AD patients than for ?4 carriers. Therefore, it might be beneficial to monitor the vitamin D status of ApoE?4 allele non-carrier AD patients.  相似文献   
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Statement of problem

The demand for ceramic restorations has increased over the past years, and now various machinable materials can be used for chairside computer-aided design and computer aided manufacturing (CAD-CAM) systems. Limited studies of these new materials make it difficult to evaluate their mechanical performance, advantages, and limitations.

Purpose

The purpose of this in vitro study was to investigate the fracture resistance of CAD-CAM monolithic ceramic and veneered zirconia molar crowns after thermomechanical aging.

Material and methods

A mandibular first molar tooth was prepared, and 12 different experimental groups were generated (n=10). An aging procedure was performed by subjecting the specimens to 12×105 mechanical cycles and 5000 thermocycles. Survival analysis was performed according to the thermomechanical aging. The fracture resistance (load at fracture) of all specimens was evaluated with 1-way analysis of variance after the means had been compared using the Tukey honest significant difference test and Weibull distributions of the experimental groups (α=.05).

Results

According to the results, the differences between the fracture resistance of the groups were found to be significant. Restorations in the dual network ceramic crown group fractured catastrophically during thermomechanical aging. In all groups, the highest value was found for monolithic zirconia, followed by monolithic lithium disilicate crowns (P<.05). Both of the monolithic crowns made of lithium disilicate derivates and zirconia crowns veneered with lithium disilicate ceramic showed no differences from each other (P>.05). The Weibull modulus (m) ranged from 4.22 to 8.58, and conventionally veneered and overpressed zirconia showed the lowest Weibull modulus values among the tested groups, indicating greater variation of the data.

Conclusions

The highest fracture resistance was observed for yttria-stabilized zirconia crowns, followed by lithium disilicate derivates. Veneered zirconia restorations generally showed lower resistance than these ceramics. The dual network ceramic crowns fractured during thermomechanical aging.  相似文献   
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