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排序方式: 共有600条查询结果,搜索用时 23 毫秒
541.
Ghada Abdel Fattah Abdel Moety Maged Almohamady Nadine Alaa Sherif Ayman N. Raslana Tarek Fawzy Mohamed Hazem Mohamed Abd El Moneam 《The journal of maternal-fetal & neonatal medicine》2016,29(3):413-417
Objective: To examine the role of first-trimester uterine artery Doppler, serum β-hCG and pregnancy-associated placental protein-A (PAPP-A) in prediction of preeclampsia and IUGR.Methods: A total of 100 pregnant women in the 11–14 weeks’ gestation were examined using uterine artery Doppler, serum β-hCG and PAPP-A. All women were followed-up for development of preeclampsia or IUGR.Results: A total of 94 women completed the study of which 7 (7.4%) developed complications. Uterine artery PI and RI were significantly higher whereas serum β-hCG and PAPP-A levels were significantly reduced in patients who developed complications when compared with those who did not. Uterine artery PI had the highest sensitivity (100%) but a low specificity (56% and 45%) in prediction of preeclampsia and IUGR, respectively. Adding PAPP-A to uterine artery PI elevated the specificity into 94.44% and 95.51%, respectively. Combined PI and β-hCG elevated the specificity into 88.89% and 89.89%, respectively.Conclusion: Our study suggests that first-trimester uterine artery impedance, as measured by Doppler ultrasound as well as low serum biomarkers (β-hCG and PAPP-A) can be used for prediction of preeclampsia and IUGR. The most sensitive is uterine artery PI. Adding β-hCG to PI improves specificity in prediction of both preeclampsia and IUGR. Uterine artery PI plus PAPP-A is the best combination for prediction of both preeclampsia and IUGR 相似文献
542.
This paper describes the extensions which have been made in Syria to the Regulatory Authority Information System RAIS 3.0. These extensions cover a wide range of functionalities in the scope of RAIS 3.0 as well as in its interface. Compatibility with the original RAIS 3.0 has been maintained. 相似文献
543.
Ayman Osama Hazem Hamed Solieman Hossam A. Zaytoun 《The Egyptian Journal of Radiology and Nuclear Medicine》2013
Virtual colonoscopy is one of the recent advances in the field of CT post processing technique. It represents a type of 3D reconstruction technique which is capable of elaborating endoscopic endoluminal display of the colon without the use of real endoscope and hence it was named virtual colonoscopy. The aim of work is to evaluate the role of virtual colonoscopy in colonic polyps. 相似文献
544.
Ayed Y Bousabbeh M Benmabrouk H Morjen M Marrakchi N Bacha H 《Lipids in health and disease》2012,11(1):84
ABSTRACT: BACKGROUND: Background: The biodiversity of the marine environment and the associated chemical diversity constitute a practically unlimited source of new active substances in the field of the development of bioactive products. In our study, we have investigated the efficiency of the venom from the Mediterranean jellyfish, Pelagia noctiluca and its fractions for anti-proliferative and anti-cell adhesion to cell-extracellular matrix activities. RESULTS: Our experiments have indicated that the separation of the Mediterranean jellyfish Pelagia noctiluca crude venom extract by sephadex G-75 chromatography led to four fractions (F1, F2, F3, and F4). Among the four fractions F1 and F3 were cytotoxic against U87 cells with IC50 values of 125 and 179 ug/ml respectively. The venom, F1, F2 and F 3 showed significant anti-proliferative activity in time-dependent manner. Our results also suggest that these fractions and the venom are able to inhibit cell adhesion to fibrinogen in dose-dependent manner. This inhibition is reliant on its ability to interact with integrins. CONCLUSION: To conclude, we have demonstrated for the first time that Pelagia noctiluca venom and its fractions especially (F1 and F2) display potent anti-tumoral properties. Separation by sephadex G-75 chromatography give rise to more active fractions than the crude venom extract. The purification and the determination of chemical structures of compounds of these active fractions are under investigation. Overall, Pelagia noctiluca venom may has the potential to serve as a template for future anticancer-drug development. 相似文献
545.
Recently, it was reported that phentolamine redosing during penile duplex can abolish a false diagnosis of venous leakage in patients with impotence. The aim of this study is to identify any useful role of phentolamine redosing in diagnosis of venogenic impotence. Sixty-seven consecutive patients complaining of weak erection for at least 6 months were included in this study. Penile color Doppler ultrasound (CDU) was performed using a 7.5 MHz linear array transducer with a color flow mapping capability. Following intracavernous injection of 20 microg prostaglandin E1 (PGE1), all patients with persistent end diastolic velocity (EDV) >5 cm/sec with an erectile response of E3 or lower, 20 min after intracavernosal injection of PGE1, were asked to revisit our clinic for a second CDU, 2 weeks later. During initial CDU examination, all 67 patients experienced poor response to 20 microg PGE1 with their average peak systolic velocity (PSV) and EDV being 42.8 and 6.6 cm/sec, respectively. The second CDU examination had similar results to the first one. Addition of 2 mg phentolamine did not significantly change the PSV and EDV of cavernosal arteries in any of the 67 patients. In conclusion, addition of intracavernous phentolamine during PGE1 CDU examination carries no advantage over the use of PGE1 alone regarding cavernosal artery response in patients with suspected venogenic EDV. 相似文献
546.
Hazem Shoirah Lawrence R. Wechsler Tudor G. Jovin Ashutosh P. Jadhav 《Journal of stroke and cerebrovascular diseases》2019,28(7):1926-1929
BackgroundA major barrier to acute stroke trial enrollment is timely access to participating centers. Establishing referral relationships via telemedicine may broaden trial access. We sought to understand the utilization of telemedicine in trial enrollment at a large academic center.MethodsThis is a single center, retrospective review of subjects consecutively enrolled into cerebrovascular trials requiring urgent consent between January 2005 and December 2016. Subjects were classified to either direct presentation to hub hospital, or transfer from spoke hospitals. We used Pearson linear correlation and a simple linear regression model to describe the relationship between annual trial enrollment rate and the number of spoke sites capable of audio-video evaluation (AVR) as a proxy for the size of the telemedicine network. We correlated the annual increase in enrollment with that of each group using parametric and nonparametric analysis.ResultsSixteen trials met our criteria, enrolling 299 subjects: 117 in the hub group and 182 in the spoke group. There was a direct relationship between the number of AVR-capable sites and annual trial enrollment rate (P = <.05). Annual increase in spoke enrollment was higher compared to hub enrollment (15.55 ± 11.30 versus 0.68 ± 1.03, P <.0005) and better correlated with total increase in enrollments (0.98 versus 0.94, P <.0001).ConclusionsTelemedicine networks are a major resource for trial enrollment. Expanding the use of remote enrollment could expedite the completion of acute cerebrovascular trials. 相似文献
547.
548.
Hazem Al-Momani Rachel Barnes Ahmed El-Hadi Rachit Shah Wyn G Lewis Paul Edwards 《World journal of gastroenterology : WJG》2012,18(44):6447-6451
AIM: To determine the incidence of human epidermal growth factor receptor 2 (HER2) over expression in oesophageal cancers.METHODS: A retrospective study, of one hundred consecutive cases of endoscopic histological samples of oesophageal cancers from a single British cancer network were included. Cancer cases were diagnosed between April 2007 and June 2010. HER2 over expression was assessed using immunohistochemistry, those that scored “0” and “+1” were considered “negative” for HER2; those that scored “+3” were considered “Positive”. Cases that were scored “+2” on immunohistochemistry further went on to have HER2 gene analysis using the Ventana HER brightfield dual-colour in situ hybridisations (HER B DISH) assay and either came back to be positive or negative for HER2 over expression. Overall survival was measured from date of histological diagnosis until date of death. 93% of the cases were followed up till five years or death, and all were followed up till two years. Cases of gastro-oesophageal junctional tumours were excluded.RESULTS: The median age of our sample was 66 years (range: 38-91 years). Eighty one were male and 19 female. Ninety-one of the cases were adenocarcinoma of the oesophagus and the rest were cases of squamous cell carcinoma. The anatomical distribution of the tumours was; upper oesophagus 2, middle oesophagus 11, and 87 were in the lower oesophagus. Operative resection was completed in 15 cases; seven cases had attempted surgical resections, i.e., open and close, 33 patients received definitive chemo-radiation and 52 had palliative treatment. Twenty-five of the cancers showed evidence of HER2 over expression, all were adenocarcinomas. Of the 25 cases that showed evidence of HER2 over expression, 21 (84%) were located in the lower third of the oesophagus. On staging, 24 out of the 25 HER2 positive cases were at stage 3 or more (13 at stage 3 and 11 at stage 4), For HER2 negative cases 37 were at stage 3 and 32 were staged as stage 4. Seventeen out of twenty five cases (68%) with HER2 over expression received palliative therapy, in comparison to thirty five out of seventy five (46.7%) in tumours not expressing HER2. No significant difference in overall survival was demonstrated between patients whose cancers showed evidence of HER2 over expression and those who did not; median overall survival for HER2 positive tumours was 15 mo (95%CI, 11-19 mo) compared to 13 mo (95%CI, 9-17 mo) for HER2 negative ones. Two years cumulative survival for cases with HER2 over expression was 33.7% compared to 31.6% in cases without HER2 over expression (P = 0.576). Only cancer’s stage significantly affected overall survival on both univariant and multivariable analysis (P = 0.034 and P = 0.009 respectively). None of the patients included in this study received Trastuzumab.CONCLUSION: Twenty-seven point five percent of oesophageal adenocarcinomas showed evidence of HER2 over expression. Routine testing for human HER2 in oesophageal adenocarcinomas can have significant implication on treatments offered to patients that may potentially affect their prognosis. 相似文献
549.
Mosaad Abdel-Aziz Hazem Dewidar Azza A. Aziz 《International journal of pediatric otorhinolaryngology》2009,73(10):1329-1333
Objective
Persistent hypernasality after adenoidectomy is an infrequent problem in children with normal palate. However if it happened, it can render a child's speech unintelligible resulting in serious affection of social life. We aimed in this study to identify the causes of persistent post-adenoidectomy velopharyngeal insufficiency and to assess the efficacy of sphincter pharyngoplasty in the treatment of such problem.Methods
This study was conducted on 18 patients complained of hypernasal speech following removal of their adenoids after variable periods of failed expected spontaneous improvement. Their hypernasality was rated as being mild, moderate and severe, all cases were subjected to conservative treatment in the form of speech therapy for 3 months to correct the problem, and patients that did not respond to speech therapy were subjected to surgical intervention in the form of sphincter pharyngoplasty. Velopharyngeal closure was assessed using flexible nasopharyngoscopy, while speech was assessed using auditory perceptual assessment and nasometry.Results
Hypernasality was mild in 9 cases, moderate in 7 cases and severe in 2 cases. Flexible nasopharyngocopy showed occult submucous cleft in 5 cases, short palate in 2 cases, and deep nasopharynx in 3 cases. Speech improvement was achieved in 8 cases after completion of speech therapy program (all had mild hypernasality with no anatomical palatal defects). Ten patients that had palatal defects were subjected to sphincter pharyngoplasty, 8 of them showed complete recovery, while 2 cases with severe hypernasality showed partial improvement of their speech.Conclusions
Persistent post-adenoidectomy velopharyngeal insufficiency may be due to anatomical abnormalities of the palate such as an occult submucous cleft, short palate or deep nasopharynx; such conditions may be overlooked during the preoperative preparation for adenoid removal. Speech therapy is an effective method in mild hypernasality especially if there is no anatomical abnormality, while surgical correction is usually needed in moderate and severe cases, and sphincter pharyngoplasty is a useful choice for those patients. 相似文献550.
Mohamed T. Abdel Aziz Taymour Mostafa Hazem Atta Mohamed A. Wassef Hanan H. Fouad Laila A. Rashed Dina Sabry 《The journal of sexual medicine》2009,6(1):49-60
IntroductionErectile response depends on nitric oxide (NO) generated by NO synthase (NOS) enzyme of the nerves and vascular endothelium in the cavernous tissue. NO activates soluble guanylate cyclase (sGC), leading to the production of cyclic guanosine monophosphate (cGMP). cGMP activates cGMP-dependent protein kinase that activates Ca2+/ATPase pump that activates Ca2+/K efflux pump extruding Ca2+ across the plasma membrane with consequent smooth muscle cell relaxation. A role similar to that of NOS/NO signaling has been postulated for carbon monoxide (CO) produced in mammals from heme catabolism by heme oxygenase (HO) enzyme.AimTo assess CO signaling pathway for erectile function by reviewing published studies.MethodsA systematic review of published studies on this affair based on Pubmed and Medical Subject Heading databases, with search for all concerned articles.Main Outcome MeasuresDocumentation of positive as well as negative criteria of CO/HO signaling focused on penile tissue.ResultsThe concept that HO-derived CO could play a role in mediating erectile function acting in synergism with, or as a potentiator for, NOS/NO signaling pathway is gaining momentum. CO/HO signaling pathway has been shown to partially mediate the actions of oral phosphodiesterase type 5 inhibitors. In addition, it was shown that the use of CO releasing molecules potentiated cavernous cGMP levels. However, increased CO production or release was reported to be associated, in some studies, with vasoconstriction.ConclusionThis review sheds a light on the significance of cavernous tissue CO signaling pathway that may pave the way for creation of therapeutic modalities based on this pathway. Abdel Aziz MT, Mostafa T, Atta H, Wassef MA, Fouad HH, Rashed LA, and Sabry D. Putative role of carbon monoxide signaling pathway in penile erectile function. 相似文献