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101.
102.
Adham Mohamed Hegazy Noha Refaat Mohamed Hala Abdalla Gaber 《The journal of maternal-fetal & neonatal medicine》2018,31(20):2649-2655
Objectives: To determine the association between 25-hydroxyvitamin D [25(OH)D] levels on first day of life with respiratory distress syndrome (RDS), need and duration of mechanical ventilation, and subsequent development of bronchopulmonary dysplasia (BPD) among preterm neonates.Study design: In this case–control study, serum 25(OH)D was measured on first day of life in 65 preterm neonates <34 weeks: 40 with RDS and 25 without RDS and compared between them. Serum 25(OH)D levels were categorized into normal (above 30?ng/ml), insufficiency (20–30?ng/ml), moderate deficiency (10–20?ng/ml), and severe deficiency (<10?ng/ml). Neonates with different 25(OH)D levels were compared as regard grade of RDS, initial pH, initial CO2, need and duration of mechanical ventilation, development of BPD, and mortality.Results: Only one of 65 studied preterm neonates had normal vitamin D level. Neonates with RDS had significantly lower mean serum 25(OH)D level than controls (10.6 versus 13.9?ng/dl) (p?=?.028). Neonates with severe 25(OH)D deficiency developed more BPD than those with moderate deficiency (29.4 versus 8.7%) but did not reach significant level (p value?=?.08). There is no correlation between serum 25(OH)D level and duration of mechanical ventilation. Logistic regression analysis shows that low serum 25(OH)D level is an independent risk factor for RDS.Conclusion: Low 25(OH)D level is far frequent among Egyptian preterm neonates. Vitamin D deficiency is an independent risk factor for development of RDS in preterm neonates. 相似文献
103.
Refaat E. Gabr Shashank Sathyanarayana Michael Schr Robert G. Weiss Paul A. Bottomley 《Magnetic resonance in medicine》2006,56(4):754-760
Destructive interference from phase fluctuations caused by motion during (1)H magnetic resonance spectroscopy (MRS) stimulated-echo acquisition mode (STEAM) and point-resolved spectroscopy (PRESS) acquisitions can significantly diminish the traditional radicalN-gain in signal-to-noise ratio (SNR) afforded by averaging N signals, especially in the torso. The SNR loss is highly variable among individuals, even when identical acquisition protocols are used. This paper presents a theory for the SNR loss, assuming that the phase fluctuates randomly. It is shown that SNR in conventional averaging is reduced by the factor sinc(sigma(phi) radical3/pi), where sigma(phi) is the standard deviation (SD) of the phase. "Constructive averaging," whereby each individual acquisition is phase-corrected using the phase of a high-SNR peak before averaging, reverses the SNR loss from motion-induced dephasing, resulting in a {1/sinc(sigma(phi) radical3/pi)}-fold SNR improvement. It is also shown that basing phase corrections on an average of radicalN adjacent points both improves correction accuracy and effectively eliminates false signal artifacts when corrections are based on low-SNR peaks. The theory is validated over a sevenfold range of variation in signal loss due to motion observed in (1)H STEAM and PRESS data acquired from 17 human subjects (heart: N = 16; leg: N = 1). Constructive averaging should be incorporated as a routine tool for in vivo (1)H MRS. 相似文献
104.
Rania Refaat Remon Zaher Elia Karim Omar ElSaeed 《The Egyptian Journal of Radiology and Nuclear Medicine》2013
Background
Comprehensive preoperative appraisal of potential living renal donors is the key for selecting a proper donor and a suitable kidney.Objective
To prospectively assess the diagnostic value of 16-slice multidetector computed tomography (MDCT) in preoperative appraisal of vascular anatomy in potential living renal donors.Materials and methods
Preoperative angiography using a 16-slice MDCT scanner was performed in 68 consecutive potential living renal donors. The MDCT angiography included unenhanced and contrast-enhanced multiphasic scans. The MDCT images were reviewed for the number and branching pattern of the renal arteries and for the number and presence of major or minor variants of the renal veins. The results were compared with the actual anatomy at the open donor nephrectomy as the diagnostic standard of reference.Results
The sensitivity and the specificity of MDCT angiography for the detection of various anatomic variants of renal arteries as well as renal venous anomalies were 100%. The anatomic variants of renal arteries included accessory arteries (n = 7) and early arterial branching (n = 10). Whereas, the detected venous anomalies were of major category of the circumaortic left renal vein anomaly (n = 2). No minor renal venous anomaly was identified in any subject.Conclusion
16-Slice MDCT angiography is highly accurate for preoperative assessment of diverse anomalies of the renal vascular anatomy in potential living renal donors; in consequence, it markedly affects the surgical planning. 相似文献105.
Ayman M. Metwally Lobna A. Refaat HebatAllah Shaaban Somaia Megm Mohamed Emara Amany A. Tohamy Eman Abou Sinna Hussein Khaled 《Journal of the Egyptian National Cancer Institute》2013,25(4):193-198
PurposeThe objective of our study was to determine the relevance of cyclins A and E overexpression in endometrial carcinogenesis in hormone receptor-positive breast cancer patients under tamoxifen therapy.Experimental designWe assessed expression of cyclins A and E in Endometrial cytology samples collected from 36 ER and PR positive breast cancer patients; under tamoxifen treatment by using the Tao-brush non-invasive brushing cytology technique. Cyclins were detected in the collected samples by means of immuno-cytochemistry.The patients included in this study are a cohort of 36 breast cancer patients who were operated upon at the National Cancer Institute – Cairo University in the period from February 2006 to May 2008 and received tamoxifen (TAM) as part of their adjuvant treatment.ResultsCyclins A and E were expressed in 17 and 15 of the 36 collected endometrial cytology samples (47.2% and 41.6% respectively).Expression of cyclins A and E was highly correlated to Tamoxifen exposure duration (32 and 43 months respectively) p < 0.001. Tamoxifen median exposure duration was shortened to 21 months in cases showing positivity for either markers, while in cases showing positivity for both cyclins, the median exposure duration was longer (44.5 months) (p < 0.001). Neither cyclin A nor E was detected before median tamoxifen exposure duration of 11 months. Endometrial carcinoma cases had the longest Tamoxifen exposure duration (60 months).ConclusionCyclins A and E expression is involved in the carcinogenesis of endometrium in women with breast cancer and under tamoxifen-treatment. Follow up of the patients using these 2 markers is highly recommended starting from the 12th month. 相似文献
106.
Waleed Ali Sayed Ahmed Magdy Refaat Ahmed Mariam Lotfi Mohamed Mostafa Ahmed Hamdy Zenab Kamel Khaled Mohamed Elnahas 《The journal of maternal-fetal & neonatal medicine》2016,29(19):3162-3166
Aim: To evaluate the clinical usefulness of maternal serum interleukin-6 for the detection of subclinical chorioamnionitis and in the prediction of the latency period in patients with preterm premature rupture of membrane (PPROM).Methods: The study group included 60 patients at 24–34 weeks of gestation complaining of PPROM. Laboratory investigations included serial measurements of IL-6, TLC and CRP. Conservative management was carried out till 36 weeks unless delivery was indicated beforehand. The main outcome measures were the latency period and the occurrence of subclinical chorioamnionitis.Results: The mean gestational age at presentation was 30.9 weeks and 35.2 weeks at delivery. The mean IL-6 level at presentation was 4.7?pg/ml. There was no correlation between IL-6 at presentation and the latency period. In addition, those diagnosed as having subclinical chorioamnionitis by placental histopathology had significantly higher levels of IL-6 at delivery. Taking IL-6 level cutoff point of 8.5?pg/ml, histological chorioamnionitis, RDS and NICU admission were significantly higher above that level while neonatal birth weight, Apgar scores at one and five minutes were significantly lower.Conclusion: Maternal serum IL-6 at the time of PPROM has no correlation to the latency period while IL-6 levels at the time of delivery have significant correlation to the subclinical chorioamnionitis and neonatal outcome measures. 相似文献
107.
MA Islam RI Chowdhury N Chakraborty W Bari HH Akhter 《The European journal of contraception & reproductive health care》2013,18(4):203-213
Objectives There are only a few studies on maternal morbidity, delivery complications and maternal mortality in Bangladesh. This study analyzes data from a follow-up study conducted by the Bangladesh Institute of Research for Health and Technologies (BIRPERHT) on maternal morbidity in rural Bangladesh in 1993. Methods A total of 1020 pregnant women were interviewed in the follow-up component of the study. The survey collected information on socioeconomic and demographic characteristics, pregnancy-related care and practice, morbidity during the period of follow-up as well as in the past, information concerning complications at the time of delivery and during the postpartum period. For the purpose of this study, we selected 993 pregnant women with at least one antenatal follow-up. Both bivariate and multivariate analyses were conducted to identify the potential risk factors for complication during delivery and duration of labor. Results and conclusions It appears that complications during the antenatal period can result in various complications at the time of delivery. Some of the important findings are: hemorrhage during the antenatal period increases the risk of excessive hemorrhage during delivery, the risk of obstructed labor increases significantly if abdominal pain is observed during the antenatal period, prolonged labor appears to be significantly higher for the first pregnancy, and pregnancies suffering from abdominal pain during pregnancy tend to have a higher risk of prolonged labor during delivery. The duration of labor appears to be negatively associated with the number of previous pregnancies, being longest for the first pregnancies. The duration of labor pain is significantly higher for the respondents who reported the index pregnancy as undesired, and, similarly, the respondents who were reported to be involved with gainful employment would have a shorter duration of labor pain than those having no involvement with gainful employment. 相似文献
108.
109.
Jun Aoki Keigo Endo Hideomi Watanabe Tetsuya Shinozaki Takashi Yanagawa Adel Refaat Ahmed Kenji Takagishi 《Journal of orthopaedic science》2003,8(3):435-441
Positron-emission tomography (PET) can provide an in vivo method for evaluating metabolism and physiology in normal and diseased
tissues. Clinical trials with [18F]2-deoxy-2-fluoro-d-glucose (FDG), the most commonly used radiolabeled tracer for PET imaging, have demonstrated increased accumulation of FDG
in several cancer tissues. In this article, we introduce the basic principles of FDG-PET and review current knowledge about
FDG-PET for evaluating musculoskeletal tumors. Recent reports and our own experience suggest that FDG-PET cannot be a screening
method for differential diagnosis between benign and malignant musculoskeletal lesions, including many neoplasms originating
from different tissues altogether. FDG-PET might not accurately reflect the malignant potential of musculoskeletal tumors,
but rather might implicate cellular components included in the lesions. A high accumulation of FDG can be observed in histiocytic,
fibroblastic, and some neurogenic lesions, regardless of whether they are benign or malignant. More specific uses of FDG-PET,
such as grading, staging, and monitoring of musculoskeletal sarcomas, should be considered for each tumor of a different histologic
subtype.
Received: October 2, 2001
RID="*" 相似文献
110.
Mohamed S. Zaghloul Eman Eldebawy Soha Ahmed Amr G. Mousa Amr Amin Amal Refaat Iman Zaky Nada Elkhateeb Mohamed Sabry 《Radiotherapy and oncology》2014