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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Iranian journal of Learning and Memory
- نوع مقاله: Journal Article
- کلمات کلیدی: Trend,math teachers,Demographic and personality variables,TIMSS studies
- چکیده:
- چکیده انگلیسی: The purpose of this study was to review the changes in the role of demographic and personality variables of mathematics teachers in predicting the mathematical progress of eighth-grade students in Iran and analyzed the trend of these variables in four international studies. For this purpose, we examined the data from 21434 eighth graders and 877 math teachers who had participated in four TIMSS studies (2003, 2007, 2011 & 2015). Among the educational variables influencing the educational development, ten variables including gender, age, history of teaching, the degree, major, teaching hours, job satisfaction, confidence, interaction with other teachers and teaching method were investigated using statistical methods of Pearson correlation coefficient and multiple regression analysis. The findings related to the demographic variables showed that the students ' mathematical performance changes were almost consonant with the changes of age, history of teaching, and teaching hours in both groups of male and female teachers. This coordination was not similar in the major and academic degrees. The results of multivariate regression showed that the students ' mathematical development was explained by the set of demographic and personality variables. Among these variables, teaching history and self - confidence of the teachers played the most important role in explaining the students ' progress, and the variables of the degree of education and gender did not contribute to the explanation of the students ' math’s progress. The findings show the necessity of paying more attention to the history of teaching and examining the reasons why major and teachers ' degree were not that influential in math development is essential.
- انتشار مقاله: 05-09-1397
- نویسندگان: Nahid Honarmand,Alireza Kiamanesh,Abdolazim Karimi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Otorhinolaryngology
- نوع مقاله: Journal Article
- کلمات کلیدی: Pediatric,Ingestion,Key words: Foreign body
- چکیده:
- چکیده انگلیسی: Introduction: Determination of type and location of trapped objects and endoscopic observations among children with foreign-body ingestion.
Materials and Methods: We evaluated 105 endoscopic records of patients presenting with foreign-body ingestion from 2001–2011.
Results: Button batteries were the most common objects removed (41%). The lower segment of the esophagus was the most common trapping site. There was significant correlation between type of foreign body and its location of trapping. Abnormal endoscopic observations were reported in 33% patients. There was significant correlation between the type of foreign body and endoscopic observations. There was also a significant correlation between the location of the foreign body and endoscopic observation.
Conclusion: The pattern of foreign-body ingestion is somewhat different in our center compared with other studies. Awareness among parents about the prevention of this accident is an important step in decreasing the incidence of foreign-body ingestion.- انتشار مقاله: 23-09-1392
- نویسندگان: Seyed Ali Jafari,Maryam Khalesi,Simin Partovi,Mohammadali Kiani,Hamid Ahanchian,Hamidreza Kianifar
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Otorhinolaryngology
- نوع مقاله: Journal Article
- کلمات کلیدی: Iran,Epidemiology,incidence,Cleft palate,Cleft lip
- چکیده:
- چکیده انگلیسی: Introduction:
Cleft lip and palate are among the most common congenital anomalies worldwide. This study was conducted in order to explore the incidence and related factors of cleft lip and/or palate (CL/P) among live births in Mashhad, North-Eastern Iran.
Materials and Methods:
In this cross-sectional study, records of 28,519 infants born between March 1982 and March 2011 at three major hospitals in Mashhad were screened for oral clefts. Clinical and demographic factors relating to diagnosed cases, including birth date, gender, birth weight, maternal age, number of pregnancies, type and side of cleft and presence of other congenital anomalies were recorded for analysis.
Results:
The overall incidence of CL/P was 1.9 per 1,000 live births. Cleft lip associated with cleft palate (CLP) was the most prevalent type of cleft (50%), followed by isolated cleft lip (35.2%) and isolated cleft palate (14.8%). A total of 92.6% of oral clefts were bilateral and 5.5% were located on the right side. In addition, clefts were found to be more common in male than female births (male/female ratio=2.3). The rate of associated congenital anomalies in CL/P newborns was 37%. No significant differences were observed in the incidence of oral clefts across three decades of study; except for CLP which was significantly more prevalent between 2002–2011 (P=0.027). There were no significant differences with regard to season of birth, associated anomalies or maternal age of affected newborns in the three time periods of the study. Furthermore, maternal age and number of pregnancies were not significantly different among the three types of cleft (P=0.43 and P=0.91, respectively). Although the mean birth weight of patients affected with isolated cleft palate was considerably lower than that of the other two types of cleft, the difference was not statistically significant (P=0.05).
Conclusion:
This study indicates a frequency of CL/P close to the findings in East Asian countries and higher than some previous reports from Iran, European and American countries. Ethnicity-related genetic factors may have a role in the conflicting results obtained from different populations.- انتشار مقاله: 13-10-1392
- نویسندگان: Hamid Reza Kianifar,Nadia Hasanzadeh,Arezoo Jahanbin,Atefeh Ezzati,Homa Kianifar
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Neonatology
- نوع مقاله: Journal Article
- کلمات کلیدی: neonate,NICU,bacterial infection
- چکیده:
- چکیده انگلیسی: Background: Among the most common causes of death in preterm infants are neonatal infections, which remain high despite antibiotic therapy and preservative measures. The control of hospital infections is now a global priority, and many factors contribute to the spread of these infections. This study aimed to determine the frequency of bacterial infections in neonates and identify the common causes of infection in neonates admitted to the neonatal intensive care unit (NICU) of Alzahra Hospital in Isfahan, Iran.
Methods: In this cross-sectional study, the population consisted of all neonates who were admitted to the NICU of Al-Zahra Hospital in Isfahan, Iran, from April 2017 to March 2018. Neonates who had a positive culture (blood, cerebrospinal fluid, urine, eye discharge, and tracheal tube secretions) were enrolled. The data were collected by a structured questionnaire, including maternal and neonatal information.
Results: In this study, 56 newborns admitted to the NICU of Alzahra Hospital in Isfahan were studied. Their age range was within 5-28 days (18.88±8.41). Thirty-two (57.1%) neonates were male, and 24 (42.9%) newborns were female. In total, 26 (46.4%) neonates had prematurity that was the most common reason for hospitalization. The most isolated microorganisms were Staphylococcus epidermidis, Enterococcus, Klebsiella, Enterobacteriaceae, Candida spp., Acinetobacter, Streptococcus pneumoniae, E. coli, and Streptococcus viridans, respectively.
Conclusion: According to the results of this study, the frequency of nosocomial infections in the NICU of Alzahra Hospital in Isfahan was 7.4%. The findings of this study highlighted the importance of paying more attention to controlling and preventing hospital infections in NICUs.- انتشار مقاله: 15-07-1397
- نویسندگان: Milad Kabiri Samani,Majid Keivanfar,Hossein Firouzi,Seyed Javad Seyedi,Hamidreza Kianifar
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Neonatology
- نوع مقاله: Journal Article
- کلمات کلیدی: Biliary atresia,cholestasis,TASC
- چکیده:
- چکیده انگلیسی: Introduction:
Early diagnosis of biliary atresia is very important for better outcome of treatment. Ultrasonography is one of the diagnostic tools for early differentiation of biliary atresia from other causes of neonatal cholestasis. It has been reported that triangular cord sign (TACS) in sonography is a reliable sign for diagnosis of biliary atresia. The aim of this study was to re-assess the accuracy of TACS alone and coupled with an abnormal gallbladder in the diagnosis of biliary atresia.
Methods:
Infants with prolonged cholestatic jaundice underwent ultrasonography and liver biopsy. Results of ultrasound scans (TASC and gallbladder abnormality) were compared with histopathological findings. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of Ultrasonographic findings for diagnosis of biliary atresia based on liver histopathology were studied.
Results:
The sensitivity, specificity and accuracy of TACS for diagnosis of biliary atresia were 36%, 95% and 77% respectively. Positive predictive value and negative predictive value was 77%. The sensitivity and specificity of gallbladder abnormality for diagnosis of biliary atresia were 36% and 88% respectively. Positive predictive value of TACS coupled with gallbladder abnormality for diagnosis of biliary atresia was 100%.
Conclusion:
The Ultrasonographic TACS is very specific for diagnosis of biliary atresia. Positive predictive value and accuracy of this sign is much higher than of gallbladder abnormality. The sensitivity of TACS for diagnosis of biliary atresia is very low.- انتشار مقاله: 02-12-1391
- نویسندگان: Seyed Ali Jafari,Mehrzad Mehdizadeh,Fatemeh Farahmand,Gholam Hossein Fallahi,Hamid Reza Kianifar
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی:
- چکیده:
- چکیده انگلیسی: Background: Well-controlled clinical studies in the developed world have shown that probiotics can shorten the duration of acute non-bacterial diarrhea. We aimed to evaluate the efficacy of a probiotic consisting of a mixture of Lactobacillus acidophilus and Bifidobacterium bifidum in the treatment of young children with acute diarrhea in Mashad, Iran Methods: Sixty-two hospital inpatients aged 6 to 36 months with acute non-bloody, non-bacterial diarrhea of a less than 2 days' duration and moderate dehydration were enrolled. Thirty-two were treated with probiotic powder three times daily for 5 days plus the routine oral rehydration solution (study group) and the other 30 were given a placebo plus oral rehydration solution (control group). Results: Mean age at the time of admission was 14.5±7 months for the study group and 13.7±6 months for controls. The mean duration of diarrhea was 3.4 days in the study group and 4.5 days in controls (P = 0.027). Duration of hospital admission was 2.1±0.7 days in the probiotic group compared with 2.7±0.6 days in the control group (P = 0.033). Average weight gain was 425 ± 9 and 370 ± 85 g for the study and control groups, respectively. Average reduction in the frequency of diarrhea per day was 4.4 ± 1.5 times for the study group and 3.6 ± 1.3 times for the control group. Conclusion: Lactobacillus acidophilus and Bifidobacterium bifidum shortened the duration of diarrhea and hospital stay, and normalized stool frequency. The use of probiotics might be recommended for treating acute diarrhea in young children.
- انتشار مقاله: 28-02-1394
- نویسندگان: Hamid Reza Kianifar,Reza Farid,Hamid Ahanchian,Farahzad Jabbari,Toktam Moghiman,Armin Sistanian
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of English for Academic Purposes
- نوع مقاله: Journal Article
- کلمات کلیدی: Collocations,formulaic language,holistic processing,linear mixed-effects modelling (LMM),psycholinguistics
- چکیده: با توجه به افزایش روز افزون علاقهمندی حیطه یادگیری زبان دوم به دانش باهمآیی کلمات، یافتههای تحقیقات بر روی پردازشهای همادین کلیشههای زبانی میتواند از این ایده که این واحدهای زبانی پرداز زبان را بهبود می بخشند حمایت می کند. این مطالعه تفاوت بین پردازش همایندها در زبان اول و زبان دوم را بررسی کرد. یک آزمایش بلندخوانی به گروهی از تکزبانهها و گروهی از دوزبانهها با مهارت بالا داده شد تا زمان واکنش آنها را نسبت به همایندهای همساز در مقایسه با ناهمایندها بررسی کنیم. با در نظر داشتن رویکرد بسامد محور نسبت به همایندها، لیستی از همایندها با بسامد بالا و لیستی از ناهمایندها تهیه شد. فرض بر آن بود که هنگامی که دوزبانهها دارای مهارت زبانی بالا هستند، نرخ پردازش آنها نباید با تکزبانهها تفاوت قابل توجهی داشته باشد. این مطالعه همچنین فرضیات مدل سیستم دوگانه را بررسی کرد. دادهها توسط مدل اثرات آمیخته خطی تحلیل شدند. نتایج آزمایش بلندخوانی نشانگر آن بود که تاثیر باهمآیی قابل ملاحظه نیست، در حالی که پردازش همایندها زمان واکنش پایین تری را در تکزبانهها در مقایسه با دو زبانهها نشان داد، که مغایر فرضیات ما و همراستا با فرضیات مدل سیستم دوگانه است.
- چکیده انگلیسی: With the renewed interest in the field of second language learning for the knowledge of collocating words, research findings in favour of holistic processing of formulaic language could support the idea that these language units facilitate efficient language processing. This study investigated the difference between processing of a first language (L1) and a second language (L2) of congruent collocations. A read-aloud task was administered to monolinguals (Persian) and advanced bilinguals (Persian-English) to assess their reaction time (RT) to collocations in comparison to non-collocations. With respect to the frequency-based approaches to the study of collocations, a list of high frequency items and a second list of non-collocations were compiled. It was hypothesised that when bilinguals are at advanced levels of proficiency their processing rate should not differ significantly from monolinguals. The study also examined the assumptions of dual-route system model (Wray, 2002). The data was analysed using linear mixed-effects modelling. The results suggested no advantage for processing of collocations over non-collocations, whereas collocational processing displayed higher response rate for monolinguals in comparison to bilinguals which contradicted our hypotheses and is in line with dual-route model assumptions.
- انتشار مقاله: 29-01-1396
- نویسندگان: Parastoo Harati Mokhtari,Reza Ghafar Samar,Gholam Reza Kiany
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Flow cytometry,Cytotoxicity,MTT assay,Anticancer agents,Carnosine analogues,Peptide synthesis
- چکیده:
- چکیده انگلیسی: Objective: Cancer has risen as the main cause of diseases with the highest rate of mortality in the world. Drugs used in cancer, usually demonstrate side effects on normal tissues. On the other hand, anticancer small peptides, effective on target tissues, should be safe on healthy organs, as being naturally originated compounds. In addition, they may have good pharmacokinetic properties. carnosine, a natural dipeptide, has shown many biological functions, including anti-oxidant, anti-senescence, anti-inflammatory and anticancer activities. This study, with the aim of introducing new anticancer agents with better properties, is focused on the synthesis and cytotoxic evaluation of some peptide analogues of carnosine.
Materials and Methods: The cytotoxic activity of the synthesized peptides, prepared by the solid-phase peptide synthesis method, was evaluated against two cell lines of HepG2 and HT-29 using MTT assay, lactate dehydrogenase (LDH) assay and flow cytometry analysis.
Results: Linear and cyclic analogues of carnosine peptide showed cytotoxicity, demonstrated by several experiments, against HepG2 and HT-29 cell lines with mean IC50 values ranging from 9.81 to 16.23 µg/ml. Among the peptides, compounds 1c, 3c and 6b (linear analogue of 3c) showed a considerable toxic activity on the cancerous cell lines.
Conclusion: The cyclic peptide analogues of carnosine withHis-β-Ala-Pro-β-Ala-His (1c) and β-Ala-His- Pro-His-β-Ala (3c) sequences showed cytotoxic activity on cancerous cells of HepG2 and HT-29, better than carnosine, and thus can be good candidates to develop new anticancer agents. The mechanism of cytotoxicity may be through cell apoptosis.- انتشار مقاله: 06-02-1396
- نویسندگان: Mohammad Hassan Houshdar Tehrani,Abdolhamid Bamoniri,Mohammadreza Gholibeikian
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: Polymerase Chain Reaction,Sequence analysis,Holstein cows,Caseins,Alleles
- چکیده:
- چکیده انگلیسی: Background: Genetic polymorphism of milk proteins has been associated with composition, manufacture, and traits of milk. Caseins are the most important milk proteins whose genes are strongly linked and inherited as a raceme. κ-casein which is a quantitatively minor constituent of bovine milk is thought to play a critical role in organization, fixation and aggregation of casein micelles and firmness of curd during cheese making. Objectives: In this study, we considered polymorphism of κ-casein gene in Iranian Holstein cows. Materials and Method: In this study, κ-casein gene polymorphism among 50 DNA samples of Iranian Holstein cows via Polymerase Chain Reaction sequence analysis (PCR-Sequencing) was considered. For data analysis SPSS 11.5 (ANOVA test) was used. Results: Four polymorphic sites that created 4 variants and seven different genotypes of κ-casein gene were identified. In this population the frequencies of A, B, C, and E alleles were estimated as 0.391, 0.413, 0.087, and 0.109 respectively. Conclusion: We suggested that the B allele of κ-casein gene frequency should be increased in Iranian Holsteins because it has an essential factor in marker-assisted selection for milk traits.
- انتشار مقاله: 22-02-1392
- نویسندگان: Zahra Molavi Choobini,Mohammad Shadkhast,Hamdollah Moshtaghi,Saeid Habibian Dehkordi,Homayon Reza Shahbazkia
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Catalysis
- نوع مقاله: Journal Article
- کلمات کلیدی: Green chemistry,Regioselective,Phase transfer catalyst,2-Nitroalcohols,Ring opening of epoxides
- چکیده:
- چکیده انگلیسی: An environmentally benign procedure for the synthesis of vicinal nitrohydrins via the regioselective ring opening reaction of epoxides with nitrite anion using silica-bound 3-{2-[poly(ethylene glycol)]ethyl}-substituted 1-methyl-1H-imidazol-3-ium bromide as an effective heterogeneous phase transfer catalyst was described. Short reaction time, high yield of products, simple work-up procedure, and recyclability of the catalyst were some of the striking features of the present protocol. The recovered catalyst could be reused five times without any loss in its catalytic activity and selectivity.
- انتشار مقاله: 30-09-1396
- نویسندگان: Neda Ayashi,Mehdi Fallah-Mehrjardi,Ali Reza Kiasat
- مشاهده