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J Oral Pathol Med (2012) 41 : 524–526 Introduction: Oral lichen planus (OLP) is a chronic, mucocutaneous, inflammatory disease. It has become more evident that the immune system plays a primary role in the development of this disease. The aim of the present study was to evaluate the total antioxidant status (TAS) of saliva and serum in patients with erosive OLP. Method and Materials: This study was designed as case‐control. In total, 48 patients with erosive OLP (34 women and 14 men) were enrolled as case group, and 44 self‐admitted healthy people (34 women and 10 men) were selected as control group. Measurement of total antioxidant status was carried out in saliva and plasma. t‐test was used for statistical analysis with significant level set at P < 0.05. Results: The mean ± SD of salivary TAS in case group was 0.98 ± 0.12, and in control group was 1.32 ± 0.18 mM, respectively, and there were significant differences between groups (P < 0.02). The mean ± SD of the plasma TAS in the case group and the control group was 1.24 ± 0.17 and 1.84 ± 0.34 mM, respectively. There were significant differences between two groups (P < 0.01). Conclusion: Our results showed that salivary and plasma levels of total antioxidant status in erosive OLP patients were lower than those in healthy subjects.  相似文献   
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Low-level laser therapy (LLLT) has been used to accelerate wound healing, yet questions remain concerning its therapeutic applications. This study aimed to compare the healing efficacy of helium-neon (He-Ne) red light (laser) and gallium aluminum arsenide (Ga-Al-As) infrared lasers at two different doses on hard palate wounds. In a randomized controlled study, 75 adult male mice were divided into five groups of 15 each, after undergoing identical surgical procedures; a control group, with no laser irradiation; HD1 and HD2 groups, treated with He-Ne laser (wavelengths 632.8 nm, power 5 mW, and spot size 0.02 cm2) at doses of 4 J/cm2 and 7.5 J/cm2 respectively; and GD1 and GD2 groups, treated with Ga-Al-As laser (wavelengths 830 nm, peak power 25 mW, and spot size 0.10 cm2) at the doses of 4 J/cm2 and 7.5 J/cm2, respectively. Five animals from each group were killed on the third, seventh, and 14 days after surgery, and biopsies were made for histological analysis. On the 3rd and 7th day after the surgery, the number of polymorphonuclear cells (PMN) in HD1, HD2, GD1, and GD2 groups was significantly lower than that of the control group. On the 7th and 14th day, the fibroblasts and new blood vessels counts and collagen density fibers in HD1, HD2, GD1, and GD2 groups were also significantly higher than that of the control groups, and the fibroblast counts and collagen density fibers in HD1 and HD2 groups were higher than that of the GD1 and GD2 groups. LLLT with He-Ne laser compared to Ga-Al-As laser has a positive healing effect on hard palate gingival wounds in mice regardless of the radiation dose.  相似文献   
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International Ophthalmology - The present study was done to evaluate efficiency of an ensemble learning structure for automatic keratoconus diagnosis and to categorize eyes into four different...  相似文献   
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Abstract

Objectives. Chest pain is a common complaint in the emergency department (ED), and it is a challenge to identify low-risk chest pain patients eligible for early discharge. We aimed to develop a simple objective decision rule to exclude 30-day major adverse cardiac events (MACE) in ED chest pain patients.

Design. We analyzed prospectively included patients presenting with chest pain. Low risk patients were identified with the clinical objective rule-out evaluation (CORE). CORE was based on high sensitivity cardiac troponin T (hs-cTnT) tests at ED presentation (0?h) and 2?h later together with a simplified risk score consisting of four objective variables: age ≥65 years and a history of arterial disease, hypertension or diabetes. For the patient to be classified as low risk in the CORE rule, hs-cTnT had to be ≤14?ng/L both at 0 and 2?h, and the sum of the risk score had to be 0. The primary outcome was MACE within 30 days.

Results. Among the 751 patients in the final analysis, 90 (11.9%) had a MACE. CORE identified 248 (33%) of patients as low risk with a sensitivity of 98.9% (CI 93.1–99.9) and a negative predictive value of 99.6% (95% CI 97.4–100) for 30-day MACE. Adding the ED physician’s interpretation of the ECG to CORE did not improve diagnostic performance.

Conclusion. A simple objective decision rule (CORE) identified one-third of all patients as having a very low 30-day risk of MACE. These patients may potentially be discharged without additional investigations for acute coronary syndrome.  相似文献   
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Introduction: The number of scientific papers is a conventional metric for the measurement of a country’s research performance in a particular area. Objective: To evaluate the trend in Iranian publications of dental research results in peer-reviewed international scientific journals over the period 1999–2009, using national and international databases, and to compare the results with other countries. Methods: The search process was performed by two independent persons in PubMed and Iranian Medline (IranMedex). Data extraction included the year of publication, total number of dental papers in each year, total number of Iranian dental papers in each year and number of papers with a high level of evidence; these were compared with those in other Asian countries. Results: The total number of dental articles indexed in PubMed during the studied period was 207,689, with 671 being written by researchers who stated their affiliation as Iran. Although the proportion of Iranian dental articles to all published dental articles was 0.01% in 1990, this increased to 1.4% in 2009. Of all clinical trials indexed in PubMed from 1990 to 2009, only 0.62% had an author from Iran. The collaboration rate of authors ranged between 1 and 10. Turkey and Iran had a larger number of dental research publications compared with other Asian countries assessed in this study. Conclusion: During the last two decades, there has been a considerable increase in the number of dental papers by Iranian researchers indexed in the PubMed database.Key words: Dental, research, Iran  相似文献   
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Traumatic brain injury (TBI) is common in young children and adolescents and is associated with long-term disability and mortality. The neuropathologic sequelae that result from juvenile TBI are a complex cascade of events that include edema formation and brain swelling. Brain aquaporin-4 (AQP4) has a key role in edema formation. Thus, development of novel treatments targeting AQP4 to reduce edema could lessen the neuropathologic sequelae. We hypothesized that inhibiting AQP4 expression by injection of small-interfering RNA (siRNA) targeting AQP4 (siAQP4) after juvenile TBI would decrease edema formation, neuroinflammation, neuronal cell death, and improve neurologic outcomes. The siAQP4 or a RNA-induced silencing complex (RISC)-free control siRNA (siGLO) was injected lateral to the trauma site after controlled cortical impact in postnatal day 17 rats. Magnetic resonance imaging, neurologic testing, and immunohistochemistry were performed to assess outcomes. Pups treated with siAQP4 showed acute (3 days after injury) improvements in motor function and in spatial memory at long term (60 days after injury) compared with siGLO-treated animals. These improvements were associated with decreased edema formation, increased microglial activation, decreased blood–brain barrier disruption, reduced astrogliosis and neuronal cell death. The effectiveness of our treatment paradigm was associated with a 30% decrease in AQP4 expression at the injection site.  相似文献   
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International Journal of Legal Medicine - Tooth development is widely used for age estimation and staging physical maturity. It is of great importance in dental age estimation in forensic...  相似文献   
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