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61.

Objectives

This study presents a biomechanical comparison of bone response to commercially pure titanium screws with four different types of surface topographies placed in the tibial metaphysis of 30 rabbits.

Materials and methods

One hundred twenty implants were tested double-blinded: (a) blasted, acid-etched, and discrete crystal deposition (DCD), (b) blasted, (c) acid-etched, and (d) blasted and acid-etch. Resonance frequency analysis (RFA/ISQ), reverse torque values (RTV), and bone-to-implant contact (BIC) were measured at the time of implant insertion (day 0), 15, 28, and 56 days of healing.

Results

All groups tested demonstrated increased RFA/ISQ and RTV results over the time course. At 15 days, the blasted, acid-etched, and DCD group demonstrated a non-significant trend toward higher values when compared to the blasted and etched group (33.0?±?16 vs. 26.3?±?12 Ncm, p?=?.16). At 56 days, the groups utilizing blasting to create additional surface roughness (Sa?>?1 micron) showed a statistical significant difference in RTQ versus the non-blasted group (38.5?±?14 vs. 29.5?±?9 Ncm, p?=?.03).

Conclusions

Within the limitations of this study, only the increase in surface roughness (Ra?>?1) at 56 days demonstrated statistically significant effects on RTQ. Other additional surface features, such as sub-micron scale DCD, demonstrated improved healing trends but without significance for clinical applications.  相似文献   
62.
63.
CD40-CD40L interactions in atherosclerosis.   总被引:32,自引:0,他引:32  
Increasing evidence supports a central role for CD40-CD40L interactions in the pathogenesis of atherosclerosis. Recently, we have shown that CD40L deficiency as well as pharmacological inhibition of CD40L in ApoE(-/-) mice results in the development of a stable atherosclerotic plaque phenotype. This phenotype is rich in smooth muscle cells and collagen, and contains only a small amount of macrophages and T-lymphocytes. CD40 and CD40L protein are present in almost all cell types in human atherosclerotic lesions. Expression was observed in early plaques, but was more predominant in advanced, rupture-prone, and ruptured plaques. Because most of the acute complications of atherosclerosis are the result of plaque rupture, CD40L inhibition might be a novel therapeutic approach to prevent atherosclerotic plaque destabilization and plaque rupture.  相似文献   
64.
65.
Malnutrition is associated with high rates of mortality among patients with end stage kidney disease (ESKD). There is a paucity of data from Bangladesh, where around 35,000–40,000 people reach ESKD annually. We assessed protein-energy wasting (PEW) amongst 133 patients at a single hemodialysis setting in Dhaka. Patients were 49% male, age 50 ± 13 years, 62% were on twice-weekly hemodialysis. Anthropometric, biochemical, and laboratory evaluations revealed: BMI 24.1 ± 5.2 kg/m2, mid-arm muscle circumference (MAMC) 21.6 ± 3.6 cm, and serum albumin 3.7 ± 0.6 g/dL. Based on published criteria, 18% patients had PEW and for these patients, BMI (19.8 ± 2.4 vs. 25.2 ± 5.2 kg/m2), MAMC (19.4 ± 2.4 vs. 22.2 ± 3.8 cm), serum albumin (3.5 ± 0.7 vs. 3.8 ± 0.5 g/dL), and total cholesterol (135 ± 34 vs. 159 ± 40 mg/dL), were significantly lower as compared to non-PEW patients, while hand grip strength was similar (19.5 ± 7.6 vs. 19.7 ± 7.3 kg). Inflammatory C-reactive protein levels tended to be higher in the PEW group (20.0 ± 34.8 vs. 10.0 ± 13.9 p = 0.065). Lipoprotein analyses revealed PEW patients had significantly lower low density lipoprotein cholesterol (71 ± 29 vs. 88 ± 31 mg/dL, p < 0.05) and plasma triglyceride (132 ± 51 vs. 189 ± 103 mg/dL, p < 0.05), while high density lipoprotein cholesterol was similar. Nutritional assessments using a single 24 h recall were possible from 115 of the patients, but only 66 of these were acceptable reporters. Amongst these, while no major differences were noted between PEW and non-PEW patients, the majority of patients did not meet dietary recommendations for energy, protein, fiber, and several micronutrients (in some cases intakes were 60–90% below recommendations). Malnutrition Inflammation Scores were significantly higher in PEW patients (7.6 ± 3.1 vs. 5.3 ± 2.7 p < 0.004). No discernible differences were apparent in measured parameters between patients on twice- vs. thrice-weekly dialysis. Data from a larger cohort are needed prior to establishing patient-management guidelines for PEW in this population.  相似文献   
66.
Journal of Neurology - The aim of the study is to analyze the ALS disease progression and respiratory function of Italian patients treated with edaravone (EVN), as well as the adherence to, and the...  相似文献   
67.
There are 4 major concepts in vascular development: vasculogenesis (formation of blood vessels from angioblasts), angiogenesis (formation of vascular sprouts from preexisting vessels), arteriogenesis (thickening and development of vessels) and lymphangiogenesis (formation of lymphatic vessels). In the last decade, these concepts, especially angiogenesis and lymphangiogenesis, have acquired major importance due to their role in tumoral growth and metastatic dissemination. Moreover, the activity of various diseases that involve chronic inflammation, such as asthma, psoriasis and rheumatoid arthritis, has been associated with vascular development. Several growth factors and cytokines are involved in this process and consequently investigation into these elements, both in peripheral blood and their expression in affected tissues, could elucidate the role of vascular development in diseases whose pathogenesis involves chronic inflammation, such as inflammatory bowel disease. The presence of distinct molecules involved in vascular development processes, such as vascular endothelial growth factor (VEGF), basic fibroblastic growth factor and placental growth factor, among others, has been studied in both ulcerative colitis and Crohn's disease, although not extensively. It has been suggested that the phenomena of vasculogenesis, angiogenesis and lymphangiogenesis play a critical, although not exclusive, role in the inflammation that characterizes inflammatory bowel disease. In general, the results obtained to date suggest that new vascular formation is involved in the pathogenesis of these diseases.  相似文献   
68.
目的:了解中国不同地区间中老年人群膝关节骨性关节炎患病危险因素。方法:调查时间为2005—07/08。①从中国六大行政区(西北,华北,华东。中南,东北,西南)选出六城市(西安,石家庄,上海。广州,哈尔滨市,成都),用分层多阶段整群抽样方法,抽取6218名40岁及以上具有正式户口常住男女人群进行膝关节骨性关节炎的流行病学问卷调查(包括一般情况、现病史、既往史、体格检查、X射线片检查情况和疾病诊断6个方面,共计94个问题141个变量指标),并对其中4808名有症状者进行X射线平片膝正侧位投照。②膝关节骨性关节炎诊断标准为临床症状阳性加X射线Kellgren & Lawrence分级二级及以上者。③计算患病率,并采用Epilnf06.0和SPSS 10.0软件对其中83个变量进行多因素非条件Logistfc回归分析,表示疾病与暴露因素之间联系强度的指标用比值比(OR),若OR〉1,说明疾病发生危险性增加,与暴露因素呈正关联;若OR〈1,说明疾病发生危险性减少,与暴露因素呈负关联。 结果:①六城市膝关节骨性关节炎总患病率为15.6%,其中西安7.7%,石家庄11.2%,上海9.8%。广州30.5%,哈尔滨16.9%,成都17.5%,各城市患病率比较差异显著(P〈0.01)。②Logistic回归分析膝关节骨性关节炎在大部分城市有共同的危险因素如年龄大(OR=1.032—1.181),使用蹲坑排便年限长(OR=1.021-1.077),体质量高(OR=1.048—1.073),和开始饮酒年龄大(OR=1.008~1.028);而从事专职体育运动(OR=1.651,西安),骨质疏松病史(OR=3.311,石家庄),吸烟(OR=2.654,石家庄),类风湿关节炎病史(OR=4.964,上海),文化程度高(OR=2.593,上海),女性(OR=2.510,广州),姐妹骨关节炎史(OR=13.251,哈尔滨),母亲骨关节炎史(OR=5.683,成都)等危险因素分别在不同地区出现. 结论:年龄大、使用蹲坑排便年限长、体质量高和开始饮酒年龄大是中国六地区膝关节骨性关节炎患病的共同危险因素,同时,不同地区主要危险因素又有一定差异。  相似文献   
69.
Background Both the safety and efficacy of biologic therapy may be affected in the presence of highly prevalent chronic viral hepatitis. Objectives To evaluate the safety and effectiveness of ustekinumab and antitumour necrosis factor therapy in patients with psoriasis and concomitant chronic viral hepatitis. Methods This was a retrospective, multicentre study. Twenty‐five patients with psoriasis and concurrent hepatitis C virus (HCV) (20 patients) or hepatitis B virus (HBV) (five patients) infection who had received at least one biologic agent (etanercept, 21 treatments; adalimumab, four; ustekinumab, four; infliximab, two) were included. Clinical, imaging and laboratory data were recorded. Results In the case of HCV infection, the majority of the patients did not exhibit increases in their viral load or serum liver tests. Aspartate aminotransferase, alanine aminotransferase and gamma glutamyl transpeptidase were doubled from the baseline measurement in only one patient treated with etanercept. Two other cases exhibited viral load increases during the follow‐up period. In total, 18 of the 26 treatments achieved a 75% improvement in their Psoriasis Area and Severity Index (PASI 75) score during the follow‐up period. Two patients treated with etanercept were diagnosed with hepatocellular carcinoma. In the case of HBV infection, all of the patients were being treated with antiviral therapy, and none presented significant variations in viral load or serum liver enzymes. All patients achieved a PASI 75 during follow‐up. Conclusions Biologic therapy was effective and safe for the majority of our patients with HCV and HBV infection, although there may be a risk of reactivation or aggravation. We describe the first cases to receive ustekinumab. The use of biologics should be limited to those cases in which the risk–benefit ratio is justified.  相似文献   
70.
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