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11.
Masoud Mohammad Andalib Masoud Mohammad Malekzadeh Zahra Agharahimi Maede Daryabeigi Bahareh Yaghmaei Mahmoud-Reza Ashrafi Ali Rabbani Nima Rezaei 《Iranian journal of pediatrics.》2015,25(5)
Background:
Tertiary pediatric hospitals usually provide excellent clinical services, but such centers have a lot to do for educational perfection.Objectives:
This study was performed to address under-graduate educational deficits and find feasible solutions.Patients and Methods:
This cross-sectional study was done in a target population of 77 sixth year undergraduate medical students (response rate = 78%) who spent their 3-month pediatric rotation in the Children’s Medical Center, the Pediatrics Center of Excellence in Tehran, Iran. The Dundee ready educational environment measure (DREEM) instrument was used for assessing educational environment of this subspecialized pediatric hospital.Results:
Among 60 students who answered the questionnaires, 24 were male (40%). Participants’ age ranged from 23 to 24 years. The mean total score was 95.8 (48%). Comparison of scores based on students’ knowledge showed no significant difference. Problematic areas were learning, academic self-perception, and social self-perception.Conclusions:
Having an accurate schedule to train general practitioner, using new teaching methods, and providing a non-stressful atmosphere were suggested solutions. 相似文献12.
Karrer M. Alghazali Zeid A. Nima Rabab N. Hamzah Madhu S. Dhar 《Drug metabolism reviews》2015,47(4):431-454
Bone loss and failure of proper bone healing continues to be a significant medical condition in need of solutions that can be implemented successfully both in human and veterinary medicine. This is particularly true when large segmental defects are present, the bone has failed to return to normal form or function, or the healing process is extremely prolonged. Given the inherent complexity of bone tissue – its unique structural, mechanical, and compositional properties, as well as its ability to support various cells – it is difficult to find ideal candidate materials that could be used as the foundation for tissue regeneration from technological platforms. Recently, important developments have been made in the implementation of complex structures built both at the macro- and the nano-level that have been shown to positively impact bone formation and to have the ability to deliver active biological molecules (drugs, growth factors, proteins, cells) for controlled tissue regeneration and the prevention of infection. These materials are diverse, ranging from polymers to ceramics and various composites. This review presents developments in this area with a focus on the role of scaffold structure and chemistry on the biologic processes that influence bone physiology and regeneration. 相似文献
13.
Khezri Mehrdad Shokoohi Mostafa Mirzazadeh Ali Tavakoli Fatemeh Ghalekhani Nima Mousavian Ghazal Mehmandoost Soheil Kazerooni Parvin Afsar Haghdoost Ali Akbar Karamouzian Mohammad Sharifi Hamid 《AIDS and behavior》2022,26(9):2831-2843
AIDS and Behavior - Injection drug use has been the leading route of HIV transmission in Iran. We assessed HIV prevalence, risk behaviors, and uptake of prevention services among people who inject... 相似文献
14.
Differential antibody recognition of FC27-like Plasmodium falciparum merozoite surface protein MSP2 antigens which lack 12 amino acid repeats 总被引:1,自引:0,他引:1
Lisa C. Ranford-Cartwright Rachel R. Taylor Nima Asgari-Jirhandeh Donald B Smith Paul E. Roberts V.Jane Robinson Hamza A. Babiker Eleanor M. Riley David Walliker & Jana S. McBride 《Parasite immunology》1996,18(8):411-420
Three alleles of the FC27-type allelic family of the MSP2 gene of the malaria parasite Plasmodium falciparum have been sequenced from parasites from the field (The Gambia and Tanzania). These alleles lack the 12 amino acid repeat units which are usual in this family of MSP2 alleles. We have investigated the recognition by sera from an endemic area (The Gambia) of three recombinant MSP2 proteins that have 5, 1 and no copies of this repeat region. Antibody recognition of these recombinant proteins varied according to the number of repeats present. High titre antibody levels were seen with most sera using the recombinant protein with 5 × 12-mer repeats, whereas only low responses were measured using proteins containing 1 or no 12-mer repeats. Several sera entirely failed to recognise the protein which lacked 12-mer repeats. The data suggest that variation in the number of tandem repeat sequences could allow the parasite to avoid high avidity antibody binding and this may allow escape from immune recognition. 相似文献
15.
Mutlu GM Dumasius V Burhop J McShane PJ Meng FJ Welch L Dumasius A Mohebahmadi N Thakuria G Hardiman K Matalon S Hollenberg S Factor P 《Circulation research》2004,94(8):1091-1100
Alveolar epithelial beta-adrenergic receptor (betaAR) activation accelerates active Na+ transport in lung epithelial cells in vitro and speeds alveolar edema resolution in human lung tissue and normal and injured animal lungs. Whether these receptors are essential for alveolar fluid clearance (AFC) or if other mechanisms are sufficient to regulate active transport is unknown. In this study, we report that mice with no beta1- or beta2-adrenergic receptors (beta1AR-/-/beta2AR-/-) have reduced distal lung Na,K-ATPase function and diminished basal and amiloride-sensitive AFC. Total lung water content in these animals was not different from wild-type controls, suggesting that betaAR signaling may not be required for alveolar fluid homeostasis in uninjured lungs. Comparison of isoproterenol-sensitive AFC in mice with beta1- but not beta2-adrenergic receptors to beta1AR-/-/beta2AR-/- mice indicates that the beta2AR mediates the bulk of beta-adrenergic-sensitive alveolar active Na+ transport. To test the necessity of betaAR signaling in acute lung injury, beta1AR-/-/beta2AR-/-, beta1AR+/+/beta2AR-/-, and beta1AR+/+/beta2AR+/+ mice were exposed to 100% oxygen for up to 204 hours. beta1AR-/-/beta2AR-/- and beta1AR+/+/beta2AR-/- mice had more lung water and worse survival from this form of acute lung injury than wild-type controls. Adenoviral-mediated rescue of beta2-adrenergic receptor (beta2AR) function into the alveolar epithelium of beta1AR-/-/beta2AR-/- and beta1AR+/+/beta2AR-/- mice normalized distal lung beta2AR function, alveolar epithelial active Na+ transport, and survival from hyperoxia. These findings indicate that betaAR signaling may not be necessary for basal AFC, and that beta2AR is essential for the adaptive physiological response needed to clear excess fluid from the alveolar airspace of normal and injured lungs. 相似文献
16.
Hafezi-Nejad Nima Gullotti David M. Bailey Christopher R. Lessne Mark L. Holly Brian P. 《Cardiovascular and interventional radiology》2022,45(1):29-40
CardioVascular and Interventional Radiology - To perform a systematic review and meta-analysis to quantify the technical success rate of adrenal venous sampling (AVS) with and without... 相似文献
17.
Sasha Taleban Nima Toosizadeh Shilpa Junna Todd Golden Sehem Ghazala Rita Wadeea Coco Tirambulo Jane Mohler 《Digestive diseases and sciences》2018,63(12):3272-3280
Background
Colonoscopy is associated with multiple adverse outcomes. With an aging population undergoing colorectal cancer screening, few modalities exist to assess the patient risk prior to colonoscopy. Frailty, the age-related decline in reserve and function across multiple organ systems, predicts poor surgical outcomes, but its role in endoscopy is unclear.Aims
This prospective cohort study assesses the efficacy of frailty in predicting acute colonoscopy outcomes.Methods
Participants aged ≥?50 years undergoing screening colonoscopy at a tertiary care center were recruited over 2 months ending in July 2017. Frailty was assessed using a validated 20-s upper-extremity frailty test, which measures the capacity of muscle performance. Demographic data, American Society of Anesthesiologists (ASA) status, and Charlson comorbidity index (CCI) were evaluated. Procedure-related adverse events and cardiopulmonary changes during and in the immediate post-procedure period were recorded. Adverse events were stratified into minor and major events. Chi-square and ANCOVA models were used in the analysis.Results
Ninety-nine adults (mean age 62.8 years) were enrolled, among which 49 were non-frail and 50 were pre-frail/frail; 50 were female. Overall, 55 participants experienced a total of 87 adverse events. Frailty and ASA status were significantly associated with colonoscopy adverse events (p?=?0.01 and p?=?0.02, respectively). Age and CCI did not predict colonoscopy outcomes.Conclusions
Compared to age and CCI, frailty status better predicts colonoscopy outcomes in older adults. Among adults undergoing colonoscopy, routine frailty screening should be considered for risk stratification. Additional prospective studies evaluating frailty measurements in endoscopy will further clarify its role in forecasting adverse events.18.
Nima Rezaei Kasra Moazzami Asghar Aghamohammadi Christoph Klein 《International reviews of immunology》2013,32(5):335-366
Primary immunodeficiency diseases (PID) are a heterogeneous group of congenital disorders of the immune system leading to recurrent infections, autoimmunity, malignancies, and hematological disorders. This review focuses specifically on inherited disorders associated with neutropenia, which may occur in isolation or as a feature of more complex immune disorders. It has been known for a long time that defined immunodeficiency syndromes, such as CD40L deficiency, WHIM syndrome, or Chédiak Higashi syndrome, may be associated with neutropenia even though the mechanisms are poorly understood. In some PID, neutropenia may result from chronic viral infection or from autoimmunity. Recently, the identification of several novel genetic defects (e.g., p14-deficiency, HAX1-deficiency, AK2-deficiency) has shed light on the pathophysiology of congenital neutropenia. This review summarizes the clinical, immunological, and genetic features of congenital neutropenia syndromes. 相似文献
19.
Surjit Lidder Nima Heidari Axel Gänsslen Wolfgang Grechenig 《Surgical and radiologic anatomy : SRA》2013,35(2):131-135
Purpose
Low anterior external fixators are constructed by placing half pins in the dense bone tunnel of the supra-acetabular region in an anterior to posterior direction. Although the placement of these pins is extra-articular, they may still breach the hip capsule on the anterior inferior iliac spine and thus be intra-capsular. We aim to provide radiological markers for the most superior fibres of the capsule to allow safe extra-capsular pin placement within the supra-acetabular bone tunnel.Methods
Thirteen cadaveric pelves were used for this study. The supra-acetabular bone tunnel was visualised with an image intensifier. The proximal most fibres of the hip joint capsule were marked with a K-wire so that their relation to the bone tunnel could be clearly seen on the images. Once all images were acquired they were calibrated and analysed to estimate the dimensions of the supra-acetabular bone tunnel and the reflection of the hip capsule.Results
The median height of the bone tunnel was 23.6 mm (18.9–33.2) and maximum width was 11.4 mm (7.6–16.3). The inferior margin of the bone tunnel was 6.7 mm (1.1–14.5) superior to the acetabular dome, and the most proximal fibres of the capsule were 9.3 mm (4.7–6.1) superior to the acetabular dome. The inferior portion of the tunnel was 3.7 mm (0.3–8.9) within the joint.Conclusion
Half pins for the construction of a pelvic external fixator should be placed in the upper half of the supra-acetabular bone corridor to minimise the risk of intra-capsular placement. 相似文献20.
Elsayed Mohammad Cheng Bernard Xing Minzhi Sethi Ila Brandon David Schuster David M. Bercu Zachary Galt James Barron Bruce Kokabi Nima 《Cardiovascular and interventional radiology》2021,44(2):254-260
CardioVascular and Interventional Radiology - To compare lung shunt fraction (LSF) prior to Y-90 radioembolization calculated using planar imaging versus SPECT/CT in patients with hepatocellular... 相似文献