the facial esthetics after orthodontic treatment and orthognathic surgery may be affected by the patient's natural head position. the purpose of this study was to evaluate the natural head position for the three skeletal classes of malocclusion.our sample consisted of 102 lateral cephalometric radiographs of patients aged 15 to 18 years; class i (n=32), class ii (n=40) and class iii (n=30). nin...

objectives: the aim of current research was the investigation of the role of classroom social psychosocial climate and shyness with academic performance of students. method: for this purpose, 370 students of third grade high schools of sabzevar city in iran, selected by clustering random sampling, and all of them filled the timidness and class social psychosocial climate questionnaires. results...

background and objective: obstructive sleep apnea (osa) is considered a common sleep disorder that increases the risk of traffic accidents among drivers. this study aimed to assess the association between mallampati score and stop-bang (snoring, tiredness, observed apnea, blood pressure, body mass index, age, neck circumference, gender) score in commercial drivers. materials and methods: 1743 m...

background and objectives: the therapeutic options for diseases caused by escherichia coli are limited. in this study we investigated the presence of virulence factors among enteropathogenic escherichia coli (epec) strains and their antibiotic resistance patterns. the isolates were also checked for the presence of class1 integrons and gene cassettes. materials and methods: this study included 7...

background: papillon-lefevre syndrome (pls) is a rare autosomal recessive disorder characterized by diffused palmoplantar keratoderma and severe periodontitis. increased susceptibility to infections due to impairment of the immune system is considered to be involved in pathoetiology of this disease. objective: according to the crucial function of hla molecules in immune responses and associatio...

previous studies have demonstrated some significant differences in hla allele frequencies in leukemic patients and normal subjects. we have analyzed hla class ii alleles and haplotypes in 60 iranian patients with acute myelogenous leukemia (aml) and 180 unrelated normal subjects. blood samples were collected after obtaining informed consents. from the patients and control dna extraction and hla...

‎let $g$ be a finite group and $z(g)$ be the center of $g$‎. ‎for a subset $a$ of $g$‎, ‎we define $k_g(a)$‎, ‎the number of conjugacy classes of $g$ which intersect $a$ non-trivially‎. ‎in this paper‎, ‎we verify the structure of all finite groups $g$ which satisfy the property $k_g(g-z(g))=5$ and classify them‎.