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111.
Leena Al-aroomy Mona Wali Mohamed Alwadeai Eman El Desouky Hatem Amer 《Medicina oral, patología oral y cirugía bucal》2022,27(3):e198
Background Odontogenic tumors (OTs) are considered important among oral lesions because of their clinicopathological heterogeneity and variable biological behavior. The purpose of this retrospective cross-sectional study was to evaluate the frequency and distribution of different types of odontogenic tumors based on the current 2017 WHO Classification of Head and Neck Tumors over a period of 5 years. This was achieved by reviewing the records of Cairo''s educational hospitals and institutions and comparing the results with findings in the literature.Material and Methods The records of patients diagnosed with odontogenic tumors were obtained from six educational hospitals and a single institute in Cairo which included: Oral and Maxillofacial Pathology Department, Faculty of Dentistry, Cairo University; General Pathology Department, Faculty of Medicine, Cairo University; Oral Pathology Department, Faculty of Dentistry, Ain Shams University; Eldemerdash Hospital, Ain Shams University; El-Sayed Galal Hospital, Al-Azhar University; Ahmed Maher Teaching Hospital and National Cancer Institute. These records were reviewed over a 5-year (2014-2018) period and the odontogenic tumors were investigated for frequency, age, gender and site. The data were recorded, then analyzed using SPSS software.Results Intraosseous (central) odontogenic tumors constituted 2.56% of all 8974 registered oral and maxillofacial biopsies. A total of 230 cases of OTs were collected and reviewed. Of these, 97.8% were benign and 2.17% were malignant. The mandible was the most commonly affected anatomic location. Ameloblastoma, with a predilection for the posterior mandible, was the most frequent odontogenic tumor (55.65%), followed by cemento-ossifying fibroma (14.78%) and odontoma (9.13%). Females were more commonly affected than males. Most of the patients were in the third and fourth decades of life. There were no peripheral odontogenic tumors diagnosed in this period.Conclusions Some similarities and differences between our findings and those of previous studies of various populations were witnessed. OTs may greatly diverge according to the version of the classification used and by the sample size of the study. Retrospective analysis of the relative frequency of OTs in different countries will be helpful in enhancing the understanding of OTs, which is important for both oral maxillofacial surgeons and pathologists. Key words:Odontogenic tumors, epidemiology, world health organization classification, oral pathology. 相似文献
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Azza A.G. Tantawy Amira A.M. Adly Eman A.R. Ismail Nevin M. Habeeb 《European journal of haematology》2013,90(6):508-518
Heart disease is the leading cause of mortality and morbidity in β‐thalassemia major (β‐TM). Aggregability of abnormal red cells and membrane‐derived microparticles (MPs) stemming from activated platelets and erythrocytes are responsible for thrombotic risk. We measured platelet and erythrocyte MPs (PMPs and ErMPs) in 60 young β‐TM patients compared with 40 age‐ and sex‐matched healthy controls and assessed their relation to clinicopathological characteristics and aortic elastic properties. Patients were studied stressing on transfusion history, splenectomy, thrombotic events, chelation therapy, hematological and coagulation profiles, flow cytometric measurement of PMPs (CD41b+) and ErMPs (glycophorin A+) as well as echocardiographic assessment of aortic elastic properties. Aortic stiffness index and pulmonary artery pressure were significantly higher, whereas aortic strain and distensibility were lower in TM patients than controls (P < 0.001). Both PMPs and ErMPs were significantly elevated in TM patients compared with controls, particularly patients with risk of pulmonary hypertension, history of thrombosis, splenectomy or serum ferritin >2500 μg/L (P < 0.001). Compliant patients on chelation therapy had lower MPs levels than non‐compliant patients (P < 0.001). PMPs and ErMPs were positively correlated to markers of hemolysis, serum ferritin, D‐dimer, vWF Ag, and aortic stiffness, whereas negatively correlated to hemoglobin level and aortic distensibility (P < 0.05). We suggest that increased MPs may be implicated in vascular dysfunction, pulmonary hypertension risk, and aortic wall stiffness observed in thalassemia patients. Their quantification could provide utility for early detection of cardiovascular abnormalities and monitoring the biological efficacy of chelation therapy. 相似文献
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Eman Hamad Dr Paul J. Mather Siva Srinivasan Sharon Rubin David J. Whellan Arthur M. Feldman 《Am J Cardiovasc Drugs》2007,7(4):235-248
Over the past 2 decades, investigators have learned more about the pathophysiologic changes that occur in systolic and diastolic dysfunction. Ironically, in some cases, the biologic pathways that have protected the heart during acute dysfunction are the same pathways that cause progressive deleterious effects with chronic activation. In particular, it is the activation of the neurohormonal system that has a significant impact on disease progression. As a result, the neurohormonal system has provided a key target for pharmacologic therapy in patients with heart failure secondary to systolic dysfunction. These targets include the renin-angiotensin-aldosterone system as well as the sympathetic nervous system. Neurohormonal manipulation, however, is often ineffective in the pharmacologic therapy of patients with endstage heart failure, therefore other treatment strategies - including the use of inotropic agents to improve pump function and diuretics to control fluid balance are needed. 相似文献
118.
M Zwirner M M Fawzy F C Bopp E Klemm-Wolfgram D Handschuh W Voelter A E Schindler 《Archives of gynecology》1983,233(4):229-240
A radioimmunoassay (RIA) procedure has been developed for the measurement of 5 alpha-pregnane-3,20-dione (DHP) in human plasma after ether extraction of the plasma-samples, followed by column chromatography. The antiserum was generated in rabbits with 6 alpha-carboxyethylmer-captoprogesterone-BSA conjugate. The high affinity (Ka = 3.72 X 10(9) l/mol) antiserum binds 40% of 40 picograms of tritiated 5 alpha-pregnane-3,20-dione at working dilutions of 1 : 2800. Negligible cross-reactivity of the antiserum was detected with 5 beta-pregnane-3,20-dione (1.8%). Other hydroxylated pregnanes showed minor cross-reactivity (5-40%). The cross-reacting steroids were all separated from pregnanedione by one chromatographic step. The plasma levels of 5 alpha-pregnane-3,20-dione were measured from 22nd to 42nd week of normal pregnancy and compared to published data. 相似文献
119.
Activity of the immediate early gene c-fos was compared across hemispheres in rats with unilateral anterior thalamic lesions. Fos protein was quantified after rats performed a spatial working memory test in the radial-arm maze, a task that is sensitive to bilateral lesions of the anterior thalamic nuclei. Unilateral anterior thalamic lesions produced evidence of a widespread hippocampal hypoactivity, as there were significant reductions in Fos counts in a range of regions within the ipsilateral hippocampal formation (rostral CA1, rostral dentate gyrus, 'dorsal' hippocampus, presubiculum and postsubiculum). A decrease in Fos levels was also found in the rostral and caudal retrosplenial cortex but not in the parahippocampal cortices or anterior cingulate cortices. The Fos changes seem most closely linked to sites that are also required for successful task performance, supporting the notion that the anterior thalamus, retrosplenial cortex and hippocampus form key components of an interdependent neuronal network involved in spatial mnemonic processing. 相似文献
120.
El-Sheekh MM El-Shouny WA Osman ME El-Gammal EW 《Environmental toxicology and pharmacology》2005,19(2):357-365
The growth of Nostoc muscorum and Anabaena subcylindrica in sterilized sewage wastewater and N. muscorum in sterilized wastewater of El-Soda Company was higher than those grown in Allen synthetic medium. Whereas, the growth of A. subcylindrica in El-Soda Company sterilized wastewater and N. muscorum as well as A. subcylindrica grown in Verta Company sterilized wastewater was slightly lower than that grown in the standard synthetic medium. The contents of chlorophyll a, carotenoids and protein of N. muscorum and A. subcylindrica grown in sterilized sewage wastewater were higher than those grown in the standard medium. Similarly, N. muscorum and the bio-mixture of N. muscorum and A. subcylindrica grown in the sterilized wastewater of El-Soda Company showed high pigments and protein contents more than those reared in Allen medium. On the other hand, the bio-mixture of N. muscorum and A. subcylindrica grown in the sterilized sewage wastewater, A. subcylindrica grown in El-Soda Company and Verta Company sterilized wastewater showed lower contents of pigments and protein compared to synthetic medium. Heavy metals, copper, cobalt, lead and manganese were removed by 12.5-81.8, 11.8-33.7, 26.4-100 and 32.7-100%, respectively, from wastewater by using cyanobacterial cultures. The metal sorption efficiency depended on the type of biosorbent, the physiological state of the cells, availability of heavy metal, concentration of heavy metal and chemical composition of wastewater. It was observed also that the single cultures in most cases was better than the mixed cultures in heavy metal removal, this may be due to the cyanobacterial competition for nutrients in mixed cultures. 相似文献