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101.
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   
102.

Background

Based on previous studies, Iran is located in a low risk area in terms of multiple sclerosis (MS). The objective of this study was to determine and compare the incidence, prevalence and demographic characteristics of MS in two ethnic groups of Persian and Arab over the period spanning 2009 in the Khuzestan province, in the Southwest of Iran.

Methods

A cross-sectional case register study was conducted between January and August 2009. All cases in the region whom were referred to the MS society in the city of Ahwaz were participants in the study. The population data from the Iranian Bureau of Statistics were used to calculate the population at risk based on the 1996 and 2006 census data.

Results

A total of 696 patients were identified according to the McDonald criteria during the last 12 years of which 569 patients were Persian. In 2009 the total prevalence and incidence rates of MS were 16.28 and 2.20 per 100,000 individuals. Based on these values, the female to male ratios were 3.11. The Persians manifested more sensory signs and symptoms (40.2%) but motor deficits (19.1%) and cerebellar findings (18.2%) were seen as being more manifest in Arab individuals. The main difference was observed in the progressive types of MS in which 24.7% of the Arab patients showed progressive type symptoms as compared to 15.9% of the cases in the Persian population.

Conclusion

According to this study the authors conclude that the prevalence and incidence of MS were higher in Persians; however progressive forms of MS with motor and cerebellar signs are more frequent in the Arab ethnic group.  相似文献   
103.
Mutations in DPAGT1 are a newly recognised cause of congenital myasthenic syndrome. DPAGT1 encodes an early component of the N-linked glycosylation pathway. Initially mutations in DPAGT1 have been associated with the onset of the severe multisystem disorder – congenital disorder of glycosylation type 1J. However, recently it was established that certain mutations in this gene can cause symptoms restricted to muscle weakness resulting from defective neuromuscular transmission. We report four cases from a large Iranian pedigree with prominent limb-girdle weakness and minimal craniobulbar symptoms who harbour a novel mutation in DPAGT1, c.652C>T, p.Arg218Trp. This myasthenic syndrome may mimic myopathic disorders and is likely under-diagnosed.  相似文献   
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105.
Carbon dioxide (CO2) is a greenhouse gas whose presence in the atmosphere significantly contributes to climate change. Developing sustainable, cost-effective pathways to convert CO2 into higher value chemicals is essential to curb its atmospheric presence. Electrochemical CO2 reduction to value-added chemicals using molecular catalysis currently attracts a lot of attention, since it provides an efficient and promising way to increase CO2 utilization. Introducing amino groups as substituents to molecular catalysts is a promising approach towards improving capture and reduction of CO2. This review explores recently developed state-of-the-art molecular catalysts with a focus on heterogeneous and homogeneous amine molecular catalysts for electroreduction of CO2. The relationship between the structural properties of the molecular catalysts and CO2 electroreduction will be highlighted in this review. We will also discuss recent advances in the heterogeneous field by examining different immobilization techniques and their relation with molecular structure and conductive effects.

Electroreduction of CO2 to CO using molecular catalysis.  相似文献   
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108.
Soluble epoxide hydrolase (sEH) inhibitors are effective in reducing blood pressure, inflammation, and pain in a number of mammalian disease models. As most classical urea-based sEH inhibitors suffer from poor solubility and pharmacokinetic properties, the development of novel sEH inhibitors with an improved pharmacokinetic specification has received a great deal of attention. In this study, a series of amide-based sEH inhibitors bearing a phthalimide ring as the novel secondary pharmacophore (P2) was designed, synthesized, and evaluated. Docking results illustrated that the amide group as the primary pharmacophore (P1) was placed at a suitable distance from the three key amino acids (Tyr383, Tyr466, and Asp335) for an effective hydrogen bonding. In agreement with these findings, most of the newly synthesized compounds demonstrated moderate to high sEH inhibitory activities, relative to 12-(3-adamantan-1-yl-ureido)dodecanoic acid as the reference standard. Compound 12e with a 4-methoxybenzoyl substituent exhibited the highest sEH inhibitory activity, with an IC50 value of 1.06 nM. Moreover, the ADME properties of the compounds were evaluated in silico, and the results revealed appropriate predictions.  相似文献   
109.
Breast cancer is the most common cancer and the second leading cause of cancer‐related death in women worldwide. In spite of huge advancements in early detection and ever‐increasing knowledge of breast cancer biology, approximately 30% of patients with early‐stage breast cancer experience disease recurrence. Most patients are chemosensitive and cancer free immediately after the treatment. About 50% to 70% of breast cancer patients, however, will relapse within 1 year. Such a relapse is usually concomitant with adenocarcinoma cells acquiring a chemoresistant phenotype. Both de novo and acquired chemoresistance are poorly understood and present a major burden in the treatment of breast cancer. Although, previously, chemoresistance was largely linked to genetic alterations within the cancer cells, recent investigations are indicating that chemoresistance can also be associated with the tumor microenvironment. Nowadays, it is widely believed that tumor microenvironment is a key player in tumor progression and response to treatment. In this study, we will review the interactions of breast tumor cells with their microenvironment, present the latest research on the resistance mediated by the stromal component in breast cancer, and discuss the potential therapeutic strategies that can be exploited to treat breast cancers by targeting tumor microenvironment.  相似文献   
110.
Neurological Sciences - The prevalence of osteoporosis is reported differently. We designed this systematic review and meta-analysis to estimate pooled prevalence of osteoporosis and osteopenia in...  相似文献   
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