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排序方式: 共有1103条查询结果,搜索用时 15 毫秒
21.
Hassan Ashktorab Omid Entezari Mehdi Nouraie Ehsan Dowlati Wayne Frederick Alfreda Woods Edward Lee Hassan Brim Duane T. Smoot Firoozeh Ghadyari Farin Kamangar Hadie Razjouyan 《Digestive diseases and sciences》2012,57(11):2924-2928
Background and Aim
Negative association has been reported between presence of Helicobacter pylori and developing gastroesophageal reflux disease (GERD) and its complications. The aim of this study was to determine whether H. pylori (HP) can be protective against GERD in an African American (AA) population.Methods
From 2004 to 2007, we studied 2,020 cases; esophagitis (58), gastritis (1,558), both esophagitis and gastritis (363) and a normal control group (41). We collected their pathology and endoscopy unit reports. HP status was determined based on staining of gastric biopsy.Results
HP data was available for 79 % (1,611) of the cases. The frequency of HP positivity in gastritis patients was 40 % (506), in esophagitis patients 4 % and in normal controls 34 % (11), while HP was positive in 34 % of the patients with both esophagitis and gastritis. After adjusting for effects of age and sex, odds ratio of HP was 0.06 (95 % CI 0.01–0.59; P value = 0.01) for the esophagitis group versus the normal group.Conclusions
Our results show H. pylori has a significant negative association with esophagitis in AAs which may point to a protective role of H. pylori in the pathogenesis of esophagitis. In addition, H. pylori may be the reason for the low GERD complications in AAs. 相似文献22.
Mehdi Sadat-Shojai Mohammad-Taghi Khorasani Ehsan Dinpanah-Khoshdargi Ahmad Jamshidi 《Acta biomaterialia》2013,9(8):7591-7621
Hydroxyapatite (HAp) is the major mineral constituent of vertebrate bones and teeth. It has been well documented that HAp nanoparticles can significantly increase the biocompatibility and bioactivity of man-made biomaterials. Over the past decade, HAp nanoparticles have therefore increasingly been in demand, and extensive efforts have been devoted to develop many synthetic routes, involving both scientifically and economically new features. Several investigations have also been made to determine how critical properties of HAp can be effectively controlled by varying the processing parameters. With such a wide variety of methods for the preparation of HAp nanoparticles, choosing a specific procedure to synthesize a well-defined powder can be laborious; accordingly, in the present review, we have summarized all the available information on the preparation methodologies of HAp, and highlighted the inherent advantages and disadvantages involved in each method. This article is focused on nanosized HAp, although recent articles on microsized particles, especially those assembled from nanoparticles and/or nanocrystals, have also been reviewed for comparison. We have also provided several scientific figures and discussed a number of critical issues and challenges which require further research and development. 相似文献
23.
Ali Monfared Arsalan Salari Ehsan Kazemnezhad Mohammadkazem Lebadi Masoud Khosravi Neda Kalantar Mehrjardi Shahrzad Rahimifar Nazly Amini 《International urology and nephrology》2013,45(6):1679-1686
Background
Micro inflammation and cardiovascular disease such as left ventricular hypertrophy (LVH) are common in hemodialysis (HD) patients. Hence, we have evaluated the relationship between high-sensitive C-reactive protein (hs-CRP), as an inflammation marker, and left ventricular mass index (LVMi) and left ventricular mass (LVM) in HD patients.Methods
An analytical cross-sectional study was performed in 104 HD patients. Serum hs-CRP, LVMi, LVM, and blood pressure were evaluated; demographic data and duration of HD were also recorded. Finally, results were analyzed by using Student’s t test, Pearson’s correlation coefficient, one-way ANOVA and multiple regression to determine the relationship between LVMi and other variables.Results
A total of 66 male patients (63.46 %) and 38 female patients, with a mean age of 51.75 ± 15.98 years-old, participated in this study. Hypertension was the most common underlying disease (65.4 %). The mean LVMi was 366.98 ± 120.89 g/m2 and the mean hs-CRP was 8.55 mg/l. Eighty-nine percent of patients had LVH. The hs-CRP level was significantly associated with age and with LVM (P = 0.0001, P = 0.039, respectively). On multivariate analysis, hs-CRP and systolic blood pressure were found to be independent predictors of LVM and LVMi.Conclusions
This study shows that hs-CRP and systolic BP are independent predictors of LVH in HD patients. 相似文献24.
Hasani-Ranjbar S Amoli MM Ebrahim-Habibi A Dehghan E Soltani A Amiri P Larijani B 《Journal of clinical research in pediatric endocrinology》2012,4(2):89-93
Objective: Hereditary hypophosphatemic rickets with hypercalciuria (HHRH) is an autosomal recessive form of hypophosphatemia with hyperphosphaturia, hypercalciuria, and hypercalcemia. In two reports on six affected kindreds with HHRH, the disease was mapped to chromosome 9q34, which contains the SLC34A3 gene that encodes the renal type 2c sodium-phosphate cotransporter. Our objective was to define the clinical course of these cases in a family with HHRH and to screen for SLC34A3 gene in order to determine whether these mutations are responsible for HHRH.Methods: After clinical and biochemical evaluations, the entire SLC34A3 gene was screened using PCR amplification followed by direct sequencing technique. In this paper, we describe a new kindred with HHRH and a case of progressive and complicated HHRH presenting at age 27 years.Results: We found 101-bp deletion in intron 9 of the SLC34A3 gene. The index patient was homozygous for this mutation which has been previously reported in a Caucasian population. This is the first report for presence of SLC34A3 intron 9 deletion in an Iranian population.Conclusions: These data showed that HHRH can be easily missed or underdiagnosed. Genetic evaluation of patients with familial hypercalciuria, hypophosphatemia and nephrolithiasis is needed for further information on the prevalence and management of this rare disorder. Conflict of interest:None declared. 相似文献
25.
Qazi Ehsan Ali Bikramjit Das Syed Hussain Amir Uzma Firdaus Abdulla Zoheb Azhar 《Egyptian Journal of Anaesthesia》2013,29(1):83-85
Meningocele is a neural tube defect where meninges protrude through a skeletal defect. Occipital meningocele compounded with the problems of paediatric airway itself pose challenges to anaesthesiologist in securing and maintaining airway. We present a case report of a 3 month-old-child with occipital meningocele posted for ventriculo-peritoneal shunt for hydrocephalus, who was successfully intubated using a size 1 Airtraq optical laryngoscope. 相似文献
26.
27.
Chao-Hsi Huang Tsung-Shun Hsieh Hsiao-Ting Chien Ehsan Eftekhari-Zadeh Saba Amiri 《International Journal of Mental Health Promotion, The》2022,24(6):825-841
In addition to the effect that the COVID-19 pandemic has had on the physical and mental health of individuals, it
has also led to a change in the mental and emotional state of many employees. Especially among businesses and
private companies, which faced many restrictions due to the special conditions of the pandemic. Therefore, the
present study aimed to design an artificial neural network with MLP technique to analyze the relationship
between demographic variables, resilience, COVID-19 and burnout in start-ups in Iran. The research method
was quantitative. Managers and employees of start-ups formed the statistical population of the study, based on
the statistical sample size of the unlimited community, 384 of them were tested. For data gathering, standard
questionnaires include of MBI-GS and BRCS and researcher-made questionnaire of stress caused by COVID-19
were used. The validity of the questionnaires was confirmed by a panel of experts and their reliability was confirmed
by Cronbach’s alpha coefficient. The number of neurons in the input layer was equal to 10, the number of neurons in
the 1st hidden layer was equal to 7, the number of neurons in the output layer was equal to 1, and the number of
epochs was equal to 500. 70% of the data were used for training and 30% for testing. In the designed artificial neural
network, all experiment data except one were correctly predicted and the obtained MAE error was less than 0.012%.
Finally, he precision and correction of the presented model was confirmed by the obtained results. 相似文献
28.
Shiva Alavi Ehsan Abolhasani Mohammadali Nilforoushzadeh 《Lasers in medical science》2016,31(3):481-484
The effects of alexandrite laser (AL) on skin parameters such as melanin content, skin layer depth, elasticity, and density have not been investigated through biometric methods. We aim to assess the effect of AL on the skin parameters through biometric devices to determine whether it has positive effects on treated region. In this pretest-posttest study, we recruited patients who attended Laser Clinic of Skin and Stem Cell Research Center, Tehran University of Medical Sciences, Tehran, Iran, from January through December 2014. Patients had to be free of any dermatologic conditions and lesion at the site of treatment or any contraindication to laser therapy. Baseline measurements were performed and patients received four sessions of AL therapy (spot size, 12 mm; fluence, 12 J/cm2; and pulse width, 5 Hz) with 4-week intervals. Four weeks after the last treatment session, the same parameters were assessed that included skin color, transepidermal water loss (TEWL), dermis and epidermis density and depth (through skin ultrasonography), melanin content, erythema intensity, and skin elasticity. Biometric parameters of 33 patients (27 females [81.8 %]), with mean (SD) age of 35.7 (9.5)?years were evaluated. The mean percent changes of skin parameters were as follows: skin color, 5.88 % through Visioface and by 56.8 % through Colorimeter devices (became lighter); melanin content, ?15.95 %; TEWL, ?2.96 %; elasticity, +14.88 %; dermis depth ?19.01 %; and dermis density, +1580.11 % (P?<?0.001 for changes in each parameter). AL could decrease melanin content of the skin and make the skin thinner while it could increase elasticity and density of epidermis and dermis, which might indicate increased collagen content of skin. 相似文献
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