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31.
This study evaluated the ability of two self-etching adhesives (a two-step and a one-step) and a conventional 3-step adhesive to bond composite to both intact and caries-affected dentin with and without thermocycling. Thirty extracted human teeth with occlusal caries were randomly assigned to three groups according to the adhesive used: Scotchbond Multi-purpose (3M) (SBMP), ClearfilSE Bond (Kuraray) (SE) and Xeno IV (Dentsply) (XEIV). The occlusal surfaces of the teeth were sectioned to expose dentin. The adhesives were applied according to manufacturers' instructions, and a composite material (Herculite XRV, Kerr) was applied and cured in increments to form a core 3 mm high. The teeth were stored in distilled water for 24 hours, then sectioned using a micro-slicing machine to obtain sections 1 mm thick. The sections were further cut to obtain rods 6 mm long and 1 x 1 mm in thickness, with dentin/composite interface located at the center. The specimens were examined microscopically to separate the caries-affected (AD) and sound dentin (SD) into two groups. Half the specimens from each group were subjected to 3,000 thermocycles (5 degrees C to 55 degrees C) prior to testing. All the specimens were then subjected to microtensile bond strength (microTBS) testing in a special apparatus. Mean microTBS was determined for each group, and data were statistically analyzed with ANOVA and Tukey's tests. Mean microTBS and standard deviation values in MPa were: SBMP-SD = 22.19 (4.6), SBMP-SD-thermocycled = 15.7 (5.55), SBMP-AD = 18.6 (2.89), SBMP-AD-thermocycled = 16.62 (6.23), SE-SD = 24.25 (5.7), SE-SD-thermocycled = 22.3 (6.7), SE-AD = 20.7 (5.55), SE-AD-thermocycled = 20.23 (6.1), XEIV-SD = 21.43 (7.6), XEIV-SD-thermocycled = 18.3 (7.11), XEIV-AD = 15.45 (6.62), XEIV-AD-thermocycled = 14.8 (3.89). ANOVA revealed a significant difference among the groups (p < .0001). The two-step self-etch adhesive resulted in highest mean microTBS values under all test conditions. However, these mean values were significantly higher than the mean values obtained with the other two adhesives under some, but not all test conditions.  相似文献   
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Purpose

Maintaining target hemoglobin (Hb) with minimal variability is a challenge in hemodialysis (HD) patients. The aim of this study is to compare the long- and short-acting erythropoietin-stimulating agents such as Aranesp and Eprex in achieving these targets.

Methods

Randomized, prospective, open-labeled study of 24 weeks includes stable patients on HD >3 months, age >18 years, and on Eprex for >3 months. Patients were randomized into two groups: A-(Aranesp group):HD patients on Eprex Q TIW or BIW were converted to Aranesp Q weekly, by using the conversion factor of 200:1 and those on Eprex Q weekly to Aranesp Q 2 weeks; B-(Eprex group):patients continued on Eprex treatment. Hemoglobin target was set at (105–125 g/l). Primary end points were percentage of patients achieving target Hb, hemoglobin variability, and number of dose changes in each group.

Results

This study consisted of 139 HD patients: 72 in the Aranesp and 67 in the Eprex—mean (SD) age 54 (16.2) years, 77 (55 %) males. About 46 % were diabetic. Target Hb achieved in 64.8 % of the Aranesp and 59.7 % in the Eprex (p = 0.006). Hb variability was less frequent in the Aranesp group (p = 0.2). Mean number of dose changes was 1.3 (0.87) in the Aranesp and 1.9 (1.2) in the Eprex (p < 0.001). There was 1 vascular access thrombosis in the Aranesp and 8 in the Eprex (p < 0.001). There was no difference in hospitalization and death number between the 2 groups.

Conclusions

Aranesp Q weekly or every 2 weeks is more efficient in achieving target Hb, with less dose changes and minor vascular access complications.  相似文献   
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Endothelin (ET) signaling provokes nephrotoxicity induced by the immunosuppressant drug cyclosporine A (CSA). We tested the hypotheses that (i): celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, counterbalances renal derangements caused by CSA in rats and (ii) the COX-2/endothelin ETB receptor signaling mediates the CSA-celecoxib interaction. Ten-day treatment with CSA (20 mg/kg/day) significantly increased biochemical indices of renal function (serum urea, creatinine), inflammation (interleukin-2, IL-2) and fibrosis (transforming growth factor-β1, TGF-β1). Histologically, CSA caused renal tubular atrophy along with interstitial fibrosis. These detrimental renal effects of CSA were largely reduced in rats treated concurrently with celecoxib (10 mg/kg/day). We also report that cortical glomerular and medullary tubular protein expressions of COX-2 and ETB receptors were reduced by CSA and restored to near-control values in rats treated simultaneously with celecoxib. The importance of ETB receptors in renal control and in the CSA-celecoxib interaction was further verified by the findings (i) most of the adverse biochemical, inflammatory, and histopathological profiles of CSA were replicated in rats treated with the endothelin ETB receptor antagonist BQ788 (0.1 mg/kg/day, 10 days), and (ii) the BQ788 effects, like those of CSA, were alleviated in rats treated concurrently with celecoxib. Together, the data suggest that the facilitation of the interplay between the TGF-β1/IL-2/COX-2 pathway and the endothelin ETB receptors constitutes the cellular mechanism by which celecoxib ameliorates the nephrotoxic manifestations of CSA in rats.  相似文献   
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Aim of this workTo assess the magnetic resonance imaging (MRI) findings compared to plain X-ray in patients with primary nodal osteoarthritis (OA) of first the carpometacarpal (CMC) joint of the thumb.Patients and methodsThis study included 35 Egyptian patients with primary nodal hand OA (HOA) and 15 healthy subjects of matched age. Each subject had plain X-rays graded by Kellgren and Lawrence (K–L) score for HOA. MRI testing of both hands done by using T1/T2 weighted axial and coronal images.ResultsThe mean age was 57.2 ± 8.3 years (45–72 years) and they were 24 females and 11 males. Disease duration of patients ranged (8 months to 10 years, 2.04 ± 1.06 years). In all HOA patients there were signs of knee OA involvement; synovial thickening in 51.4% of patients, knee effusion in 8.6%, limited knee ROM in 28.6% and night pain in 60%. There was a superiority of the MRI in detecting synovitis (71.4%), flexor tenosynovitis (71.4%), collateral ligament (60%), bone marrow lesion (85.7%) and cysts (57.1%) compared to the X-ray which could not detect them. MRI significantly detected osteophytes (88.6%), joint space narrowing (91.4%), erosions (85.7%) and malalignment (57.1%) compared to X-ray (51.4%, 62.9%, 34.3% and 14.3% respectively) (p < 0.001, p = 0.004, p < 0.001 and p < 0.001).ConclusionMRI is superior in detecting HOA changes compared to conventional radiography. As OA is recognized to involve the whole joint, modern imaging techniques such as MRI could be a valuable tool for better evaluation of HOA.  相似文献   
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Aim of the workThis study was conducted to assess serum level of growth differentiation factor-15(GDF-15) in Behcet’s disease (BD) patients and its relationship with clinical characteristics, ultrasound findings and disease activity.Patients and methodsStudy included 30 BD patients and 20 matched healthy controls. Visual analog scale (VAS)-pain of affected joints and Behcet’s disease current activity form (BDCAF) were assessed. The most affected joints and surrounding soft tissues were assessed by musculoskeletal ultrasound (MSUS).Serum GDF-15 level was measured.ResultsPatients were 23 males and 7 females (M:F 3.3:1) with a mean age of 34.6 ± 8.6 years and mean disease duration of 6.6 ± 4.5 years. 18(60%) had arthritis and arthralgia. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were 26.2 ± 21.2 mm/1sthr and 50.4 ± 37 mg/dl respectively. There was significant increase of GDF-15 levels in patients with articular affection (3492.3 ± 4618.8 ng/ml) compared to those without (338.9 ± 90.3 ng/ml) and controls (322 ± 78.8 ng/ml) (p < 0.001).As regard MSUS, knee (n = 8) and ankle joints (n = 8) were the most commonly affected joints. Synovitis was present in 13 patients, enthesopathy was present in 10. GDF-15 significantly correlated with ESR and CRP (r = 0.48;p = 0.008 and r = 0.73, p = 0.005) and both remained significant on regression analysis that ESR (p = 0.019 and p = 0.007 respectively). At a serum GDF-15 cut-off point of 570 ng/ml for patients with peripheral arthritis/arthralgia the sensitivity and specificity were 88.9% and 91.7% respectively.ConclusionSerum GDF-15 can be used as a marker for articular affection in BD patients and is associated with the MSUS imaging visualizing subclinical inflammatory changes.  相似文献   
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We studied the healing efficacy of cimetidine or placebo in 23 endoscopically proven duodenal ulcer outpatients in a randomized, controlled, prospective, double-blind trial. There were 11 patients in the cimetidine (1200 mg daily) treatment group and 12 patients in the placebo-treated group. No antacid was allowed, but a placebo antacid with no neutralizing capacity was given as needed for pain. The incidence of complete endoscopic healing at 2, 4, and 6 weeks was 54%, 63%, and 72% in the cimetidine-treated patients and 8%, 50%, and 67% in the placebo-treated patients. There was a statistically significant difference (P<0.05) in complete duodenal ulcer healing between both treatment groups after 2 weeks of therapy, but there was no significant difference at the 4- and 6-week observation periods. The incidence of complete pain relief at 2 and 4 weeks was 64% and 82% in the cimetidine-treated patients and 67% and 75% in the placebo-treated patients. At 6 weeks of treatment there was no increase in the number of patients with complete pain relief in either group. There was no significant difference between the two groups in the incidence of ulcer pain relief at any of the three observation periods. Duodenal ulcer healing rates and duodenal ulcer pain relief were compared at 2, 4, and 6 weeks. There was no statistical association between ulcer healing and complete pain relief in the placebo treatment group at the 2-week evaluation period, but there was statistical association (P<0.05) in the cimetidine treatment group at 2 weeks and both treatment groups at the 4- and 6-week evaluation periods. The results of this study demonstrate that in duodenal ulcer outpatients treated for 6 weeks: (1) cimetidine increases the incidence of duodenal ulcer healing during the first 2 weeks of treatment; (2) more than 50% of duodenal ulcers will spontaneously heal during a 4 to 6-week observation period which is not statistically modified by cimetidine treatment; (3) the complete relief of duodenal ulcer pain is not influenced by treatment with cimetidine when compared to placebo.  相似文献   
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