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排序方式: 共有1215条查询结果,搜索用时 15 毫秒
1.
Objectives: Coenzyme Q10 (CoQ10, ubiquinone) stands among the safest supplements in the elderly to protect against cardiovascular disorders. Noteworthy, CoQ10 deficiency is common in many surviving stroke patients as they are mostly prescribed statins for the secondary prevention of stroke incidence lifelong. Accordingly, the current study aims to experimentally examine whether CoQ10 supplementation in animals receiving atorvastatin may affect acute stroke-induced injury.

Methods: Adult rats underwent transient middle cerebral artery occlusion after atorvastatin pretreatment (5 or 10 mg/ kg/day; po; 30 days) with or without CoQ10 (200 mg/kg/day). After 24 hours ischemic/reperfusion injury, animals were subjected to functional assessments followed by cerebral molecular and histological to detect inflammation, apoptosis and oxidative stress.

Results: Animals dosed with 10 mg/kg presented the worst neurological function and brain damage in the acute phase of stroke injury. CoQ10 supplementation efficiently improved functional deficit and cerebral infarction in all stroke animals, particularly those exhibiting statin toxicity. Such benefits were associated with remarkable anti-inflammatory and anti-apoptotic effects, based on the analyzed tumor necrosis factor-α, interleukin-6, Bax/Bcl2 and cleaved caspase 3/9 immunoblots. Importantly, our fluoro-jade staining data indicated CoQ10 may revert the stroke-induced neurodegeneration. No parallel alteration was detected in stroke-induced oxidative stress as determined by malondialdehyde and 8-oxo-2′-deoxyguanosine levels.

Discussion: These data suggest that all stroke animals may benefit from CoQ10 administration through modulating inflammatory and degenerative pathways. This study provides empirical evidence for potential advantages of CoQ10 supplementation in atorvastatin-receiving patients which may not shadow its antioxidant properties.  相似文献   

2.
Osteomas are benign slow growing tumors of bone. Tumors are usually asymptomatic until they attain remarkable size and cause asymmetry or dysfunction. In view of few reported cases of giant osteoma of mandible, this article presents a case of giant osteoma of left mandible in a 53-year old male causing dyspnea due to compression of air way space.  相似文献   
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BACKGROUND: The objective of this multicenter, randomized trial was to compare enamel matrix derivative (EMD; test) with barrier membranes (control) for the treatment of mandibular buccal Class II furcation defects. METHODS: Forty-five patients with 90 comparable defects on contralateral molars were included. Defects were randomly assigned to EMD or bioabsorbable barrier membrane; the contralateral defect received the alternative treatment. Assessments at baseline and 8 and 14 months included gingival margin levels, probing depths, bleeding on probing, vertical attachment levels, and vertical bone sounding from a stent at five buccal sites/ tooth. Defect dimensions were recorded at surgery and during reentry at 14 months. Change of open horizontal furcation depth was the primary outcome variable. Adverse reactions and patient perceptions were also noted. RESULTS: Both treatment modalities led to significant clinical improvements. The median reduction of open horizontal furcation depth was 2.8 mm with the corresponding interquartile interval (1.5 mm, 3.5 mm) at test sites compared with 1.8 mm (1.0 mm, 2.8 mm) at control sites. The Hodges-Lehmann estimator of the advantage (reduction test versus control) was 0.75 mm (95% confidence interval [CI]: 0.125 mm, 1.375 mm, P = 0.033, Wilcoxon). The frequency of complete furcation closure was 8/45 (test) and 3/45 (control); partial closure, 27/45 in both groups; no change, 9/45 and 11/45, respectively; and deterioration, 1/45 and 4/45, respectively. The frequency of no pain or no swelling at 1 week post-surgery was 62% and 44%, respectively, at the test sites and 12% and 6% at the control sites. CONCLUSION: There was a significantly greater reduction in horizontal furcation depth and a comparatively lower incidence of postoperative pain/swelling following enamel matrix derivative compared to membrane therapy.  相似文献   
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Spring-mediated mandibular distraction osteogenesis   总被引:4,自引:0,他引:4  
Successful performance of distraction osteogenesis requires rigorous patient compliance with a daily activation regimen of a percutaneous screw. Previous clinical studies have found that failure of patient compliance with this regimen is the most common complication leading to technical failure of the distraction process. The authors have developed an internalized spring-mediated device for mandibular distraction osteogenesis that can potentially abrogate the risks associated with patient compliance by allowing for automated distraction across an osteotomy. Twenty adult New Zealand White rabbits underwent unilateral mandibular osteotomy. A segment of nickel-titanium shape memory alloy reinforced at both ends with a pinball was fashioned into an inferiorly based arc and secured to the mandible with stainless steel wire. On postoperative day 12, spring activation commenced by cutting a wire binding the two pinballs to one another. Animals were observed for 6 weeks before they were killed. Radiographic studies and decalcified histologic analysis were performed on extracted mandibles. Temperature- and displacement-dependent properties of the shape memory alloy were also examined. Five animals were excluded from the study due to infection, nonunion, or device failure. A mean distraction of 1.2 mm in the distracted hemimandible relative to the nonoperated hemimandible was found (P <.001, two-tailed paired t test). The maximum distraction achieved in an experimental specimen using the spring distractor was 3.7 mm. There were no other histologic or radiographic differences found between study specimens and specimens subjected to traditional distraction methods. Biomechanical testing of the shape memory alloy revealed a temperature-dependent increase in force at body temperature compared with room temperature and a reduction in force with increased displacement of the spring. This study demonstrates the feasibility of spring-mediated distraction osteogenesis across an osteotomy. As the field of distraction osteogenesis matures, the next level of sophistication in the clinical development of devices will incorporate technology that permits fully internalized and automated distraction to occur.  相似文献   
7.

Purpose

This study aimed to determine effects of community-based healthy lifestyle education on the incidence of metabolic syndrome (MetS) in Tehranian children considering parental factors during a 13-year follow-up.

Methods

This study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS) on 1603 healthy children, aged 8–18 years, who had complete parental data. Parental factors including MetS, education, age, occupation, and smoking were considered to distinguish parental clusters which could potentially predispose children to MetS. Lifestyle interventions were aimed at achieving healthy dietary patterns and increasing physical activity. Cluster analysis and survival Cox model were used to determine potential low and high risk parental clusters and the effect of intervention on the hazard of MetS in children respectively.

Results

In a model adjusted for children’s age and sex, the hazard of the MetS incidence was 36% higher in children from high-risk parental cluster than those from low-risk parental cluster (HR = 1.36, 95% CI = 1.07–1.73). Moreover, the intervention group showed a 39% lower risk for MetS incidence (HR = 0.61, 95% CI = 0.44–0.85) compared to controls, during the first 6 years after baseline assessment (short term), although the risk lowering effect of the intervention was not maintained long term.

Conclusion

A healthy lifestyle education was successful in reducing the short-term risk of MetS in children. To identify ways of maintaining long-term results, further research is definitely warranted.

Trial Registration

This study was funded by National Research Council and Planning and Management Organization and has been reviewed and approved by the Iranian registry of clinical trials (ISRCTN52588395).
  相似文献   
8.
A total of 150 bovine (60), ovine (42), and caprine (48) bulk milk samples were analyzed using a commercially available competitive ELISA kit. Overall, AFM1 was found in 46.7 % of the analyzed samples by an average concentration of 40.3 ± 22.2 ng/L. The incidence rates of AFM1 contamination in bovine, ovine, and caprine bulk milk samples were 66.7, 31.0, and 35.4 %, respectively. The concentration of AFM1 in 37.5 % of AFM1-positive bovine milk samples and 5.9 % of AFM1-positive caprine milk samples were higher than 50 ng/L.  相似文献   
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10.
Background: Aberrant immune responses are evident in the pathogenesis of multiple sclerosis (MS) and it has been proposed that the spectrum of cytokines influence disease outcomes. Leptin and lipopolysaccharide (LPS) of Gram-negative bacteria are both potent cellular stimulators for production of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α). The aim of this study was to compare the TNF-α production by peripheral blood monocytes from MS patients with healthy controls.

Methods: Peripheral blood samples were stimulated with LPS or leptin. After blocking the Golgi apparatus, intracellular cytokine production was assessed using a monoclonal antibody against human TNF-α by the flow cytometry technique. Moreover, plasma level measurement of cytokines was performed using enzyme-linked immunosorbent assay (ELISA).

Results: Intracellular levels of TNF-α were 16.80?±?8.21 and 16.52?±?8.23in MS patients and healthy controls which showed no statistically significant difference between them (p?=?0.850). Leptin-stimulated and LPS-stimulated TNF-α production showed no significant difference between MS patients and the control group (p?=?0.263 and p?=?0.191, respectively). However, after treatment with leptin, a weak significant difference was shown between cases and control group (p?=?0.049). There were significant differences between cases and controls regarding serum levels of IL-6 and Toll-like receptor-4 (TLR-4) before and after stimulation with leptin and LPS, separately (p?<?0.05).

Conclusion: Taken together, we cannot definitely conclude that TNF-α does not play an important role in pathogenesis of MS. However, other characteristics of monocyte activation such as IL-6 or TLRs can elucidate implication of peripheral blood monocytes in MS pathogenesis.  相似文献   
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