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The present work aimed to investigate the dry sliding wear behaviors of hybrid polymer matrix composites made up of Kevlar, bamboo, palm, and Aloe vera as reinforcement materials of varying stacking sequences, along with epoxy as the matrix material. Three combinations of composite laminates with different stacking sequences such as AB, BC, and CA were fabricated by a vacuum-assisted compression molding process. The influence of composite laminates fabricated through various stacking sequences and dry sliding wear test variables such as load, sliding distance, and sliding velocity on the specific wear rate and co-efficient of friction were investigated. Experiments were designed and statistical validation was performed through response surface methodology-based D-optimal design and analysis of variance. The optimization was performed using grey relational analysis (GRA) to identify the optimal parameters to enhance the wear resistance of hybrid polymer composites under dry sliding conditions. The optimal parameters, such as composite combinations of CA, a load of 5 N, a sliding velocity of 3 m/s, and a sliding distance of 1500 m, were obtained. Furthermore, the morphologies of worn-out surfaces were investigated using SEM analysis.  相似文献   
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Warts are tumors or growths caused by infection with human papilloma virus (HPV). Currently, over 170 HPV types have been identified. This study aimed to evaluate the efficacy and safety of intralesional injection of methotrexate (MTX) for the treatment of plantar warts. Sixty patients presented with plantar warts were divided into two groups. Group A patients were injected with intralesional MTX (2 mg/ml). Group B patients were injected with intralesional saline as a placebo. The injections were repeated every week for a maximum of six sessions or until complete clearance, whichever was earlier. The patients were followed up for 6 months after the last injection. In the intralesional MTX group, 2 patients (6.7%) showed complete improvement, 8 patients (26.7%) showed partial improvement, and 20 patients (66.7%) showed no improvement. In the intralesional saline group, 3 patients (10%) showed complete improvement, 4 patients (13.3%) showed partial improvement, and 23 patients (76.7%) showed no improvement. Reported adverse events were local reactions in the form of swelling, pain, and infection in both groups. There was no statistically significant difference between the therapeutic responses to intralesional MTX injection and saline.  相似文献   
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Alopecia areata (AA) is an autoimmune form of nonscarring hair loss. The aim of the study was to assess the serum concentration of interferon gamma (IFN‐γ) and CD8 cell expression in lesional skin biopsies in correlation with the disease severity, activity, duration, and trichoscopic findings in patients with AA. The study included 30 patients with AA and 15 age‐ and sex‐matched healthy controls. Trichoscopy was performed and photographs were captured for the alopecic areas, and the enzyme‐linked immunosorbent assay technique was used for serum level of IFN‐γ assessment and immunohistochemistry for CD8 cells. The results obtained indicate that IFN‐γ serum level in patients was significantly higher than that of control subjects, and significantly correlated with the activity status and the duration of the disease. CD8+ T cells infiltrate intensity significantly correlated with severity. Yellow dots (YDs), vellus hair, black dot, and exclamation marks were the most common trichoscopic findings. The presence of black dots significantly correlated to the disease activity, duration, serum IFN‐γ, and CD8+ infiltrate intensity. The presence of YDs significantly correlated with the mean serum IFN‐γ level. Exclamation marks significantly correlated with the disease activity and the degree of CD8+ infiltrate. In conclusion, trichoscopy could be a reliable indicator of the IFN‐γ serum level and CD8+ T cell infiltrate intensity in AA patient.  相似文献   
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Journal of Neurology - We aimed to determine suicide risk and lifetime suicidal ideation in Parkinson disease (PD) patients versus controls and how depression, demoralization, and insomnia are...  相似文献   
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IntroductionThe clinical identification of metabolic syndrome is based on measures of abdominal obesity, atherogenic dyslipidemia, elevated blood pressure, and glucose intolerance. However, the impact of hypogonadism associated with obesity on penile hemodynamics is not well investigated.AimIn this retrospective study, we sought to evaluate the effect of obesity on serum total testosterone (TT) level and penile duplex parameters in men with erectile dysfunction (ED).MethodsOur participants (N = 158) were evaluated for erectile function using an abridged, five-item version of the International Index of Erectile Function-5. Determination of body mass index (BMI) was performed. Measurements of TT, fasting lipid profile, and blood sugar were conducted. Penile hemodynamics was assessed using intracavernosal injection and penile duplex study.Main Outcome MeasuresBivariate associations among BMI and serum testosterone, blood pressure, and lipid profile, as well as penile duplex parameters. We compared all clinical, laboratory, and penile duplex parameters between lean men (BMI < 25) and overweight and obese men (BMI  25).ResultsThe participants' age ranged between 20 and 56 years. A significant negative correlation between BMI and TT was detected (r = −0.431, P = 0.0001). Hypogonadism was identified in 54/158 (34.2%) of men with ED. The incidence of hypogonadism varied from as low as 1/18 (5.6%) in lean men to as high as 18/36 (50%) to 21/35 (60%) in morbid and severe obesity, respectively. Vasculogenic ED was detected in 32/54 (59.3%) men with BMI  25, compared with 5/18 (27.8%) in lean men (P = 0.029). In order to study the effect of obesity on erectile function, cases with other risk factors were excluded. Of 67 men suffering from ED with no other risk factor(s) apart from obesity, vasculogenic ED was detected in 32/54 (59.3%) men with BMI  25, compared with 3/13 (23.1%) in lean men (P = 0.029).ConclusionObesity is associated with lower TT and disturbances of penile hemodynamics. It is an independent clinical factor for vasculogenic ED. Zohdy W, Kamal EE, and Ibrahim Y. Androgen deficiency and abnormal penile duplex parameters in obese men with erectile dysfunction. J Sex Med 2007;4:797–808.  相似文献   
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OBJECTIVES: To audit the management of vascular trauma in Kuwait, 1992-2000. DESIGN: Retrospective open study. SETTING: Vascular surgery unit, teaching hospital, Kuwait. SUBJECTS: 155 patients with vascular injuries, most of which (n = 118) involved the extremities. 21 had neck injuries, 10 abdominal, and 6 chest. INTERVENTION: Revascularisation usually using the long saphenous vein in addition to direct repair or end-to-end anastomosis. MAIN OUTCOME: Morbidity (amputation) and mortality. RESULTS: Four lower limb grafts failed, two of which (2/69, 3%) required amputation. Overall, four patients died (3%), one of pulmonary embolism and 3 of severe injuries to major abdominal vessels. 3/10 patients with abdominal vascular trauma died. Mean (SD) follow up period was 4.4 (2) years. CONCLUSIONS: Civilian violence has increased in Kuwait. Vascular trauma to abdominal vessels is associated with high mortality. Autogenous saphenous vein forms an excellent conduit for revascularisation.  相似文献   
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