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41.
In this study, the X-ray and gamma attenuation characteristics and optical properties of a synthesized tellurite–phosphate–sodium oxide glass system with a composition of (85 − x)TeO2–10P2O5–xNa2O mol% (where x = 15, 20, and 25) were evaluated. The glass systems we re fabricated by our research group using quenching melt fabrication. The shielding parameters of as-synthesized systems, such as the mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), effective atomic number (Zeff), half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), and effective electron density (Neff) in a wide energy range between 15 keV and 15 MeV, were estimated using well-known PHY-X/PSD software and recently developed MIKE software. Herein, the optical parameters of prepared glasses, such as molar volume (VM), oxygen molar volume (VO), oxygen packing density (OPD), molar polarizability (αm), molar refractivity (Rm), reflection loss (RL), and metallization (M), were estimated using MIKE software. Furthermore, the shielding performance of the prepared glasses was compared with that of commonly used standard glass shielding materials. The results show that the incorporation of sodium oxide into the matrix TeO2/P2O5 with an optimum concentration can yield a glass system with good shielding performance as well as good optical and physical properties, especially at low photon energy.  相似文献   
42.
A novel series of 1,3,5-triazine analogs was successfully synthesized through conjugation with benzimidazole or 1,2,4-triazole derivatives via a methylenethio linker. The new analogs were in vitro evaluated against HSV-1 in Vero cells; among these analogs, two compounds exhibited good effect in inhibiting HSV-1 replication (for compound 5p: EC50 = 3.5 μg/ml, SI = 358; for compound 5r: EC50 = 5.0 μg/ml, SI = 300) in comparison to acyclovir.  相似文献   
43.
44.
During the last decade, the rapid economic development in Saudi Arabia resulted in an unbalanced dietary intake pattern within the general population. Consequently, metabolic syndrome was also documented to be highly prevalent in the Middle-East region. We aimed to examine the relationship between selected dietary nutrient intakes and the prevalence of metabolic syndrome in the general adult population of Riyadh, Saudi Arabia. In this cross-sectional study, 185 adult Saudis aged 19 to 60 years (87 males and 98 females (mean age 35.6 ± 13.2 and 37.6 ± 11.7 years, respectively)) were included. The criteria for metabolic syndrome were based on the International Diabetes Foundation (IDF) criteria, and the dietary food intake was assessed by two 24-h dietary recall methods. The odd ratios (ORs) of metabolic syndrome risk across quartiles of selected dietary nutrients were significantly lower for carbohydrates and proteins, as well as for vitamins A, C, E and K, calcium, zinc and magnesium (p < 0.05 for all) in the female group with metabolic syndrome than those without. The pattern of daily dietary intake of selected nutrients among the general population of Saudi Arabia raises concern, and this dietary imbalance could increase the risk of metabolic syndrome, particularly in adult Saudi females.  相似文献   
45.

Purpose

To report the initial misdiagnosis of patients with Vogt–Koyanagi–Harada (VKH) disease.

Methods

The medical records of 76 consecutive patients diagnosed with VKH disease were reviewed retrospectively at The Eye Center, Riyadh, Saudi Arabia. Patients were referred to The Eye Center from Saudi Arabia and other Middle Eastern countries. The initial diagnosis was made by an ophthalmologist or neurologist. The main outcome measure was to evaluate cases with VKH disease who were initially misdiagnosed.

Results

In 7 (9.2%) out of the 76 patients the initial diagnosis was incorrect. Patients were initially misdiagnosed as optic neuritis (1.3%), intracranial hypertension (1.3%), brain tumor (1.3%), Susac disease (1.3%), migraine (1.3%), rhegmatogenous retinal detachment (1.3%) or anterior granulomatous uveitis of unknown etiology (1.3%). Patients underwent unnecessary tests including MRI and invasive procedures including CSF analysis and anterior chamber paracentesis.

Conclusion

The initial diagnosis of patients with VKH disease was incorrect in 9 % of the cases. Delay in the diagnosis of VKH disease may lead to delay in management and may cause irreversible damage to the photoreceptors with poor visual outcome.  相似文献   
46.
The treatment of keloid and hypertrophic scar is challenging with no universally accepted mode for permanent ablation. Conventional therapies yield unpredictable results, significant complications and require elaborate hardware.

Objective

The objective was to establish the safety and efficacy of intralesional 5-fluorouracil (5-FU) for the treatment of keloids and hypertrophic scars.

Study design

Randomized controlled trial (RCT).

Place and duration

It was conducted at the Jinnah Burn and Reconstructive Surgery Center/Allama Iqbal Medical College, Lahore, Pakistan from May 2012 to March 2013.

Subjects and methods

We included 120 patients divided in two groups. The group A patients received intralesional triamcinolone acetonide (TAC) and the group B patients received both 5-FU and TAC. 8 injections at a week interval were given and patients were evaluated at the start of treatment and then at 4th and at 8th week during the treatment and then 4 weeks after the end of treatment. Patents were assessed for mean reduction in scar height, efficacy and complications.

Results

Total of 108 patients completed the study. The mean reduction in the scar height in group B (5-FU + TAC) 1.144 + .4717 was markedly better than that of group A (TAC alone) 1.894 + 1.0751 (t = 4.781, p = .000). The efficacy (defined previously as >50% reduction in initial scar height) was superior in group B 44 (77.2%) than that of group A 25 (49.0% (X2 = 9.260, p = .002). Recurrence was seen in 39.2% (20) of patients of the group A while in only 17.5% (10) of the cases of group B (P = 0.012). Mean follow up was of 22 months.

Conclusion

5-FU + TAC is safe, easy to administer and effective treatment for problematic scars and has the lower rate of recurrence on larger follow up.  相似文献   
47.
Health care professionals need to approach their profession with a view to life long learning. They need to develop a strategy to meet their learning needs in a reflective and effective manner. Continuous medical educational (CME) is the traditional tool for learning and updating knowledge. Most of them are in the forms of courses, conferences, journal clubs and workshops. They are mostly didactic sessions and evidence suggests that they are not effective to improve the clinical skills and attitude. Systematic review of teaching evidence-based medicine shows that interactive and clinically integrated learning is the most effective form of learning. It enhances knowledge and skills. Professionals should view CME in a holistic manner in the context of continuous professional development (CPD) and even in the wider concept of knowledge translation, which encompasses both CME and CPD. e Learning is one of the most important forms of non-traditional CME. It provides an efficient and increasingly interactive delivery system that can handle complex and layered information. More work needs to be done to see its effectiveness for practising clinicians.  相似文献   
48.
49.
We report the case of a 7-month-old boy who presented with a history of vomiting since birth. A computed tomography study showed circumferential thickening of the lower oesophageal wall with enhancement of the mucosa. After a period of antireflux medication, the patient underwent simultaneous oesophageal dilatation and Nissen fundoplication. He is doing well at 2-year follow up.  相似文献   
50.
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