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21.

Background/purpose  

Many studies suggest a role for antioxidants in the prevention of lung hypoplasia in nitrofen-induced rat models with congenital diaphragmatic hernia (CDH). This study investigates the oxidative status and the histological outcome of prenatal administration of vitamins E and C with synergistic effect, and effect of N-acetylcysteine (NAC) to improve lung maturation of nitrofen-induced rats.  相似文献   
22.
OBJECTIVE: This study was conducted to show dimensional and volumetric changes after vertical alveolar distraction osteogenesis using a three-dimensional computed tomography measurement method. MATERIALS: Four patients with mandibular alveolar ridge atrophy were evaluated. Three-dimensional computed tomography reconstructions were obtained 2 weeks before and 3 months after the operation. The results of the three-dimensional computed tomography measurements were used for preoperative planning and for quantitative assessment of the mandibular alveolar distraction. The results of the preoperative and postoperative three-dimensional computed tomography measurements were compared statistically using paired t-test. RESULTS: The increase in distracted mandibular segment volume and surface area, height, and width of each slice after distraction were statistically significant (P < 0.001). CONCLUSION: In atrophic jaw cases, the dimensions of the present alveolar bone were clearly measured so that the amount of augmentation needed could be estimated. Three-dimensional computed tomography provided better understanding of the effects of distraction osteogenesis on the anterior mandible. Newly formed bone can be viewed as close to its real dimensions after distraction osteogenesis.  相似文献   
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The aim of this in vitro study was to evaluate the yield strengths of glass fibre-reinforced composite (FRC) posts and zirconia dioxide ceramic (ZDC) posts. Tapered glass FRC posts (DentinPost) and ZDC posts (Cerapost) of three sizes in diameter (ISO 50, 90, 110) were used for bending tests. Conventional prefabricated titanium posts of the same sizes served as control groups. The 0.2% yield strengths (R(0.2)) were tested on a universal testing machine. As zirconia posts fractured before they were yielded 0.2%, the fracture strength instead of the yield strength was recorded for these posts. One-way and two-way anova and Bonferroni-Dunn's multiple comparison tests were performed for the statistical analysis. The mean 0.2% yield strengths of the posts were 27 +/- 1 N for glass fibre-reinforced posts and 58 +/- 4 N for zirconia posts of ISO 50 (control group: 54 +/- 3 N). For ISO 90 yield strengths of 52 +/- 4 N for glass fibre-reinforced posts, 117 +/- 20 N for zirconia posts and 117 +/- 11 N for the control group were obtained. For ISO 110 mean yield strengths amounted to 73 +/- 5 N for glass fibre-reinforced posts, 166 +/- 23 N for zirconia posts and 141 +/- 12 N for the control group. Significantly higher yield strength was recorded for the zirconia and the titanium posts compared with the glass fibre-reinforced posts for the tested ISO sizes.  相似文献   
25.
The effect of 5 different surface conditioning methods on bonding of metal brackets to cast dental alloys was examined. The surface conditioning methods were fine (30-microm) or rough (125-microm) diamond bur, sandblasting (50-microm or 110-microm aluminum oxide [Al2O3]), and silica coating (30-microm silica). Fifty disc-shaped specimens of 5 different alloys (gold-silver, palladium-silver, nickel-chromium, cobalt-chromium, and titanium) were ground with 1200-grit silicone carbide abrasive and polished before being reused for each conditioning method. Polished surfaces were used as negative controls. After measuring surface roughness (RZ), metal brackets were bonded to the conditioned alloys with a self-curing resin composite. Specimens were thermocycled (5000 times, 5 degrees-55 degrees C, 30 seconds), and shear bond tests were performed. Significantly higher (P<.001) surface roughnesses were observed with use of the rough diamond bur (RZ approximately 33 microm), 110-microm Al2O3 (RZ approximately 14 microm), and fine diamond bur (RZ approximately 10 microm), compared with the controls (RZ approximately 1 microm). Silica coating (RZ approximately 4 microm) and 50-microm Al2O3 (RZ approximately 4 microm) demonstrated no significant difference (P>.001) in roughness when compared with the controls. The control group showed no resistance to shear forces (0 MPa). Bond values were greater (19 MPa) when silica coating was used, compared with 50-microm Al2O3 (7 MPa) and 110-microm Al2O3 (8 MPa) for all alloys tested. However, interaction between alloys and conditioning methods exhibited significant differences (P<.0001).  相似文献   
26.
Studies that explored the anterior visual pathway in the patients with multiple sclerosis (MS) have demonstrated contradictory results about the correlation between structural and functional status of optic nerve and retina. We aimed to investigate the functional and structural findings in our cohort of mildly disabled relapsing-remitting MS patients. A total of 134 eyes (80 eyes of the patients with MS and 54 eyes of the control group) were investigated. Eyes of MS patients were divided into two groups—as eyes with history of optic neuritis (ON group) and without history of optic neuritis (NON group). Ophthalmological investigation including visual evoked potentials, standard automated perimetry, and optical coherence tomography were performed for all participants. Retinal and macular thicknesses were significantly decreased in ON and NON groups compared with controls. Also, visual evoked potential latencies and visual field loss were worse in the both MS groups compared with control group. We did not find any correlation between visual evoked potentials and retinal or macular thickness values but visual field parameters were correlated between retinal and macular layer loss in the NON group. According to our results and some previous studies, although both functional and structural changes were detected in patients with MS, functional status markers do not always show parallelism (or synchrony) with structural changes, especially in eyes with history of optic neuritis.  相似文献   
27.

Background

Many scoring systems have been developed to predict the prognosis of the traumatized patients in Emergency Departments, and the necessary calculations make complex scoring systems difficult to use as a part of the initial trauma patient assessment, and they also have limited accuracy.

Study Objective

This study compares the accuracy of cystatin C with trauma scoring systems in predicting the mortality of trauma patients.

Methods

Serum cystatin C levels were measured upon arrival in consecutive adult multiple blunt trauma patients during a 12-month period. Correlation analysis was used to assess the relationship between Injury Severity Score (ISS), Revised Trauma Score (RTS), Glasgow Coma Scale (GCS) Score, and cystatin C. Trauma scores and cystatin C were used in Cox regression models to predict trauma patients' risk of death.

Results

During the study period, 153 patients were enrolled and 18 died. There were negative correlations between cystatin C levels and the GCS (r = −0.666, p < 0.001) as well as the RTS (r = −0.229, p = 0.004). A moderate correlation was found between the ISS and the cystatin C level (r = 0.492, p < 0.001). In Cox regression models, every increase in units of cystatin C levels and ISS (the cut-off levels were 0.93 mg/L and ≥ 16, respectively) results in a 4.22- and 1.068-fold increase in mortality, respectively.

Conclusion

Cystatin C may represent an important severity-of-illness indicator, easily available to clinicians during the initial assessment of trauma victims on admission.  相似文献   
28.
ObjectiveIntrahepatic cholestasis of pregnancy is a temporary, pregnancy-specific disease that resolves with delivery, characterized by itching (pruritus), as well as high transaminase and serum bile acid levels in the third trimester of pregnancy. Due to the effects of Autotaxin on the physiology of pregnancy, we aimed to investigate Autotaxin activity in patients with intrahepatic cholestasis of pregnancy.Patients and methodsSixty-nine patients diagnosed with intrahepatic cholestasis of pregnancy and 20 healthy pregnant women were enrolled in the study. Fasting serum bile acid, pruritus intensity, serum parameters, gestational week of the patients at the time of diagnosis were recorded, and birth week and birth weight were monitored. Autotaxin serum level was measured enzymatically.ResultsThe mean serum bile acid level (n = 69; 38.74 ± 35.92 μmol/L) in patients with intrahepatic cholestasis of pregnancy (n = 69) was detected to be higher than healthy pregnant women (n = 20; 5.05 ± 1.88 μmol/L) (p < 0.001). Weak correlation was detected between serum bile acid level and itch intensity (p = 0.014, r = 0.295), while no relation was detected between Autotaxin and itch intensity (p = 0.446, r = 0.09). Although mean Autotaxin (intrahepatic cholestasis of pregnancy: 678.10 ± 424.42 pg/mL, control: 535.16 ± 256.47 pg/mL) levels were high in patients with intrahepatic cholestasis of pregnancy, it was not statistically significant (p = 0.157).ConclusionIn our study, we observed that the serum Autotaxin level did not make a significant difference in patients with intrahepatic cholestasis of pregnancy compared to healthy pregnant women. These findings suggest that larger clinical studies are required to reveal the physio-pathological effects of Autotaxin on pregnancy.  相似文献   
29.
The pathophysiology of pre-eclampsia is still unknown thus effective primary prevention is not possible at the stage. The present study was conducted to research the smooth muscle responses in the pre-eclampsia model with suramin treated rats and the effect of phosphodiesterase-5 (PDE5) inhibitor on these responses. Rats of three groups; control, suramin and suramin+sildenafil were given intraperitoneal injections of saline, suramin or sildenafil citrate. Suramin injections caused increased blood pressure, protein in urine and caused fetal growth retardation. The use of sildenafil citrate straightened significantly both blood pressure and average fetus weight, but did not reach to control values. At the end of pregnancy, thoracic aorta rings were exposed to contractile and relaxant agents. KCl contraction responses, sodium nitroprusside and papaverine relaxation responses were similar in three groups. Contraction responses of phenylephrine, increased significantly in suramin group. Relaxation responses of acethylcholine and bradykinin decreased in suramin group. The use of sildenafil citrate partially straightened both relaxation and contraction responses, but did not reach to control values. In all groups in the presence of L-nitromonomethylarginine (L-NAME), 1H-(1, 2, 4) oxadiazole (4, 3-a) guinoxalin-1-one (ODQ) and indomethacin decreased the relaxation responses of acetylcholine and bradykinin. The cyclic guanosine monophosphate (cGMP) content of thoracic aorta tissue was determined by radioimmunoassay technique. The content of cGMP in suramin group decreased and use of sildenafil citrate increased the cGMP content but did not reach to control values. We conclude that in pre-eclampsia, the increase of contraction responses, the decrease of relaxation responses and the decrease of cGMP content can depend on insufficiency about synthesis or release of relaxant factors which was released from the vessel endothelium. The results in this study show that in pre-eclampsia; PDE5 inhibitors enhance endothelial function and may be used for protection. Further studies are needed to clear the efficiency and safety of PDE5 inhibitors.  相似文献   
30.
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