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Separation Anxiety Disorder(SAD) is one of the earliest anxiety disorders. The effect of this disorder on the performance of children and adolescents reveals the need for awareness of the prevalence and comorbidity of this disorder in each region. This study is a cross-sectional analytical study implemented in all provinces of Iran. The instrument used in this study is the Persian version of the Kiddie Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version(K-SADA-PL) questionnaire. The total number of participants was 29,699. The overall prevalence of SAD was 5.3%. The comorbidity rate of 65.3% was found between SAD and other psychiatric disorders. Specific phobia and oppositional defiant disorder had the highest comorbidity with this disorder in the studied population. The more prevalence of separation anxiety disorder in the age range of 6–9 years old highlights the need for early detection of this disorder and targeting screening programs in childhood and adolescence.

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Objectives To investigate the CYP1A2 genotype-phenotype relationship and to compare CYP1A2 genetic polymorphisms and enzyme activity in terms of the effect of smoking and oral contraceptive (OC) use in Swedes and Koreans. Methods CYP1A2 enzyme activity was determined in 194 and 150 healthy Swedish and Korean subjects, respectively, on the basis of the 4-h plasma paraxanthine/caffeine (17X/137X) ratio determined using high-performance liquid chromatography. Genotyping for the −3860G>A, −2467delT, −739 T>G, −729 C>T, −163C>A and −3113A>G polymorphisms was performed by PCR-restriction fragment length polymorphism analysis. Results The mean 17X/137X ratio was 1.54-fold higher in Swedes than in Koreans (mean difference: 0.16; 95% CI of the mean difference: 0.12, 0.20; p < 0.0001). Smokers had a significantly higher 17X/137X ratio (higher CYP1A2 activity) than non-smokers, while Swedish OC users had a significantly lower 17X/137X ratio than non-users (mean difference: 0.31, 95% CI of the mean difference: 0.23, 0.39; p < 0.0001). No effect of gender differences on enzyme activity was observed. Four known (CYP1A2*1A, *1D, *1F, and *1L) and two novel haplotypes (CYP1A2*1V and CYP1A2*1W) were found. CYP1A2*1K was rare in Swedes and absent in Koreans. No significant genotype-phenotype relationship was observed, with the exception of CYP1A2*1F in Swedish smokers, where it was associated with higher enzyme inducibility (p = 0.02). Koreans displayed a significantly lower mean 17X/137X ratio than Swedes having the same CYP1A2 genotype, smoking habit and OC use. Conclusions We found significant differences in CYP1A2 enzyme activity between Swedes and Koreans that could not be explained by environmental factors or the CYP1A2 haplotypes examined, despite differences in allele frequencies. None of the investigated CYP1A2 haplotypes are critical in inducing variations in enzyme activity, with the exception of CYP1A2*1F.  相似文献   
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Background  Gastro-oesophageal reflux disease (GERD) is a growing health-care problem with variable distribution.
Aim  To assess GERD prevalence and risk factors and their possible correlation with pathophysiology in a population-based study.
Methods  Individuals aged 18–65 years were enrolled through random cluster sampling in Tehran. Previously validated self-administered questionnaires were used.
Results  Of the 2500 questionnaires, 2057 were analysed (mean age: 34.8 ± 13.0 years, 55.1% female). Frequent GERD was seen in 18.2%. Minor symptoms increased prevalence. Female gender (OR: 1.55, 95% CI: 1.01–2.41), BMI >30 kg/m2 (OR: 1.79, 95% CI: 1.03–3.12), less education (OR: 1.52, 95% CI: 1.02–2.27), smoking (OR: 1.83, 95% CI: 1.12–2.99), NSAID use (OR: 4.23, 95% CI: 1.66–10.74) and GERD in spouse (OR: 1.82, 95% CI: 1.18–2.82) were associated with frequent GERD on multivariable analysis. GERD in first-degree relatives (OR: 1.73, 95% CI: 1.23–2.43) and asthma (OR: 4.09, 95% CI: 1.27–13.15) correlated with infrequent GERD. Minor symptoms correlated with GERD history in first-degree relatives, coffee consumption and NSAID use. Prevalence in the past 3 months was similar to that in the past 12 months ( P  < 0.05).
Conclusions  Gastro-oesophageal reflux disease is common in Tehran. The association of 'infrequent symptoms' with GERD history in first-degree relatives and 'frequent symptoms' with GERD history in spouse may point to the presence of yet unknown precipitating environmental factors inducing GERD in a genetically susceptible host. Minor GERD symptoms seem to have independent contribution to GERD. Assessing GERD in the past 3 months predicts prevalence in the past year.  相似文献   
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Disease recurrence in surgically treated lung adenocarcinoma (AC) remains high. New approaches for risk stratification beyond tumor stage are needed. Gene expression‐based AC subtypes such as the Cancer Genome Atlas Network (TCGA) terminal‐respiratory unit (TRU), proximal‐inflammatory (PI) and proximal‐proliferative (PP) subtypes have been associated with prognosis, but show methodological limitations for robust clinical use. We aimed to derive a platform independent single sample predictor (SSP) for molecular subtype assignment and risk stratification that could function in a clinical setting. Two‐class (TRU/nonTRU=SSP2) and three‐class (TRU/PP/PI=SSP3) SSPs using the AIMS algorithm were trained in 1655 ACs (n = 9659 genes) from public repositories vs TCGA centroid subtypes. Validation and survival analysis were performed in 977 patients using overall survival (OS) and distant metastasis‐free survival (DMFS) as endpoints. In the validation cohort, SSP2 and SSP3 showed accuracies of 0.85 and 0.81, respectively. SSPs captured relevant biology previously associated with the TCGA subtypes and were associated with prognosis. In survival analysis, OS and DMFS for cases discordantly classified between TCGA and SSP2 favored the SSP2 classification. In resected Stage I patients, SSP2 identified TRU‐cases with better OS (hazard ratio [HR] = 0.30; 95% confidence interval [CI] = 0.18‐0.49) and DMFS (TRU HR = 0.52; 95% CI = 0.33‐0.83) independent of age, Stage IA/IB and gender. SSP2 was transformed into a NanoString nCounter assay and tested in 44 Stage I patients using RNA from formalin‐fixed tissue, providing prognostic stratification (relapse‐free interval, HR = 3.2; 95% CI = 1.2‐8.8). In conclusion, gene expression‐based SSPs can provide molecular subtype and independent prognostic information in early‐stage lung ACs. SSPs may overcome critical limitations in the applicability of gene signatures in lung cancer.  相似文献   
77.
We have investigated the in vitro immunogenicity and in vivo prophylactic and therapeutic potential of lambda (λ) phage particles displaying the E75 peptide (derived from HER2 protein) in an implantable TUBO breast tumor model of BALB/c mice. The mice were immunized with the E75-displaying phage (λF7-gpD::E75) every 2-week intervals over a 6-week period, and the generated immune responses were studied. Results showed in vitro induction of immune responses by the λF7 (gpD::E75) construct compared to the control λF7 and buffer groups. In the in vivo prophylactic study, all the control and vaccinated mice groups developed tumors. However, in the therapeutic experiments, we observed a significant difference in tumor size at days 14–36 for mice immunized with λF7 (gpD::E75) compared to control groups (P?<?0.05). Moreover, the survival time prolonged in mice immunized with λF7 (gpD::E75). The discrepancy between the results obtained from the in vitro and in vivo studies may have been a result of the induction of Foxp3 CD4+CD25+ which has been previously reported to hamper effective T cell functionality. In conclusion, we observed a significant immune stimulatory response in the in vitro study, while in vivo, the vaccine was not able to exert significant tumor inhibitory effects. We suggest that the presence of Foxp3+ CD4+CD25+ cells may have impaired the anti-tumor response in mice challenged in vivo with the TUBO xenograft tumor.  相似文献   
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Background

Burn injuries impose a considerable burden on healthcare systems. It is among the top ten causes of mortality and a major cause of disability. This study aimed to calculate and compare the lethal area fifty percent (LA50) and standardized mortality ratio (SMR) in patients with burns.

Methods

This is a five-year cross-sectional study. The study population consisted of 3284 patients with acute burns who were admitted to the Burn Department of Imam Reza Hospital in Mashhad, Iran, from 2010 to 2015. LA50 and SMR were calculated. SPSS 16 was used for logistic regression analysis.

Results

The mean percentage of burn total body surface area (TBSA%) was 37.0 (25.5), and deceased patients with burns had a significantly higher burn TBSA% than alive discharged patients (70.3 (24.2) vs. 28.1 (17.1), p < 0.001). The most common cause of burn was fire (71.7%). The total case fatality rate was 21.2%. However, this index was more than double in females than in males (31.9% vs. 14.3%, p < 0.001). The SMR, based on the abbreviated burn severity index (ABSI), increased from 61% to 80% during the 5-year period. LA50 for total admitted patients was 63.8% (95% confidence interval [CI] = 60.4–67.7). LA50 for scalds was the highest (72.1%) compared to those of other types of mechanisms of burn injuries. TBSA, age, and gender were found to be mutually independent predictors of death.

Conclusion

The trend of LA50 in these five years declined by 12%, whereas the SMR was below 100%. Improvement in burn management quality in high-risk groups including the elderly, females, and patients with extensive burns may improve LA50 in burn units. However, LA50 alone is not a conclusive index for the performance of a burn department, and it should be interpreted alongside with SMR.  相似文献   
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With more than two billion infected people, from whom 350 to 400 million suffer from chronic infection, hepatitis B virus (HBV) is still a major health problem worldwide. As dental treatment puts both dentists and patients at a higher risk of HBV infection, dentists can play an important role in preventing HBV transmission in dental settings. This study was performed to evaluate dental students' awareness and practice regarding HBV-related issues and to compare the results obtained from different academic years. One hundred and forty-two questionnaires consisting of questions on students' knowledge of HBV and preventive measures against this virus were completed by third- to sixth-year dental students of Tehran University of Medical Sciences (TUMS), Tehran, Iran. Overall, a relatively good level of knowledge was observed amongst this population. However, students' answers to practice questions were less satisfying. It is noteworthy that in some cases students of higher academic years showed less awareness. This finding highlights the necessity of continued infection control education. TUMS students must complete an infection control workshop before they start their clinical education. The authors propose that such training at the beginning of each academic year would be worthwhile.  相似文献   
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