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611.
Atrial fibrillation (AF) is a common clinical problem in elderly patients and especially in those with heart failure (HF). It is a major risk factor for serious cardiovascular events, such as stroke, HF and premature death. Both the prevalence and incidence of AF increase with age and its prevalence in the United States are estimated at more than 2.2 million, with nearly 75% of patients aged >65?years. Aging-related atrial remodeling with fibrosis, dilation and mitochondrial DNA mutations predispose elderly patients to AF. Current management options for AF, including rate control and anticoagulation therapy, can be successfully applied to the elderly population. New antiarrhythmic and anticoagulation medications such as dronedarone and dabigatran, respectively, can impact the approach to therapy in the elderly. Non-pharmacological options such as catheter-based ablation have also gained prominence and have been incorporated into the guidelines for management of AF. However, more trials in the elderly and very elderly segments are needed to clarify the safety and long-term efficacy of the new treatment options. 相似文献
612.
SR Mohebbi M Rostami Nejad SM Tahaei MA Pourhoseingholi M Habibi P Azimzadeh H Naghoosi P Karayiannis MR Zali 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2012,106(9):528-531
Hepatitis A virus (HAV) and hepatitis E virus (HEV) are enteric hepatotropic viruses and their prevalence is related to the sanitary conditions of the region under investigation. There are only a few studies on the seroepidemiology of these two viruses in the general Iranian population. The purpose of this investigation was to measure the prevalence of hepatitis A and E infections in the general population. Between 2006 and 2007, a cross sectional study was performed in Tehran, Iran. Blood specimens were collected and questionnaires were filled in for 551 persons. Patient sera were tested by ELISA for anti-HEV and anti-HAV IgGs. The χ(2) test and independent t-test were used for statistical analysis and p<0.05 was considered significant. The overall seroprevalence rates of anti-HEV IgG and anti-HAV IgG were 9.3% and 90%, respectively. The prevalence of antibodies to HAV and HEV was greater among men than women and increased with age. However, there was no significant relationship between age and gender with the existence of anti- HAV and HEV IgG antibodies. Our results show the seroprevalence of HAV and HEV antibodies are high and both viruses are endemic in this region. These findings are in accordance with results obtained from previous studies. We recommend that foreign travelers to Iran are vaccinated against HAV. 相似文献
613.
Bahareh Bahman-Bijari Arash Malekiyan Pedram Niknafs Mohammad-Reza Baneshi 《Iranian journal of pediatrics.》2011,21(2):151-158
Objective
Application of Continuous Positive Airway Pressure (CPAP) in neonate with respiratory distress is associated with reduction of respiratory failure, reduced complications and mortality. Bubble CPAP (B-CPAP) and ventilator-derived CPAP (V-CPAP) are two most popular CPAP modes. We aimed to determine whether B-CPAP and V-CPAP would have different survival rate and possible complications.Methods
This prospective clinical trial was performed on 50 preterm neonates weighing 1000-2000 gr who were admitted to the neonatal intensive care unit of Afzalipoor Hospital because of respiratory distress between June 2009 and May 2010. Patients were randomly allocated into treatment groups using minimization technique. Survival analysis was applied to estimate and compare survival rates. Duration of oxygen therapy, hospital stay as well as hospitalization costs were compared using independent sample t-test.Findings
Estimated survival rates at 24 hours in B-CPAP and V-CPAP groups were 100% and 77% respectively. Corresponding figures at 48 hours were 100% and 71%. In addition the hospitalization cost in V-CPAP group was significantly higher than in B-CPAP group.Conclusion
According to our results, B-CPAP was effective in the treatment of neonates who were suffering from respiratory distress and reduced the duration of hospital stay. In addition to mentioned benefits, its low cost may be the reason to use B-CPAP broadly compared with V-CPAP. 相似文献614.
Kaposi's sarcoma and other manifestations of human herpesvirus 8 总被引:1,自引:0,他引:1
Geraminejad P Memar O Aronson I Rady PL Hengge U Tyring SK 《Journal of the American Academy of Dermatology》2002,47(5):641-55; quiz 656-8
Kaposi's sarcoma (KS) was described by Moritz Kaposi in 1872 and was known for an entire century as a rare disorder of older men usually of Eastern European, Mediterranean, and/or Jewish origin. In the early 1980s, the prevalence of KS began to increase dramatically and soon became the most common malignancy in patients with AIDS, especially those who were male homosexuals. In 1994, a new human herpesvirus (HHV) was found to be present in almost 100% of KS lesions. This virus was found to be a gammaherpesvirus, closely related to Epstein-Barr virus, and was designated HHV-8. Subsequently, HHV-8 DNA was found in almost all specimens of classic KS, endemic KS, and iatrogenic KS, as well as epidemic KS (ie, AIDS KS). It is now believed that HHV-8 is necessary, but not sufficient, to cause KS and that other factors such as immunosuppression play a major role. The use of highly active antiretroviral therapy (HAART) since 1996 has markedly reduced the prevalence of AIDS KS in western countries, but because 99% of the 40 million patients with AIDS in the world cannot afford HAART, KS is still a very common problem. Primary effusion lymphoma and multicentric Castleman's disease are also thought to be due to HHV-8. Although HHV-8 DNA has been described in a number of other cutaneous disorders, there is little evidence that HHV-8 is of etiologic significance in these diseases. The mechanism by which HHV-8 causes KS, primary effusion lymphoma, and multicentric Castleman's disease is not well understood but is thought to involve a number of molecular events, the study of which should further our understanding of viral oncology. (J Am Acad Dermatol 2002;47:641-55.) Learning objective: At the completion of this learning activity, participants should be familiar with Kaposi's sarcoma and other manifestations of human herpesvirus 8. 相似文献
615.
In the present study, we tested the significance of mitochondria for apoptosis upon exposure to tamoxifen and etoposide using two human breast cancer cell lines, MCF-7 and MDA-MB-231. We showed that both tamoxifen and etoposide induced apoptosis, increased intramitochondrial calcium and nitric oxide, and decreased mitochondrial transmembrane potential in both cell lines. Both drugs increased mitochondrial protein tyrosine nitration and caused release of cytochrome c from the mitochondria of both cell lines. This study suggests that tamoxifen and etoposide utilize a common mechanism to induce apoptosis in MCF-7 and MDA-MB-231 cells. 相似文献
616.
617.
Hamid-Reza Moein Ahmad Kheirkhah Rodrigo T. Muller Andrea C. Cruzat Deborah Pavan-Langston Pedram Hamrah 《The ocular surface》2018,16(2):218-225
Purpose
To evaluate the long-term alterations of corneal nerves in patients with herpes simplex virus (HSV) keratitis using in vivo confocal microscopy (IVCM).Design
Prospective, longitudinal, cross sectional.Methods
This study included 16 patients with a history of HSV keratitis and 15 age-matched normal controls. Slit-scanning IVCM was performed in all subjects at baseline and then after a mean follow-up of 37.3?±?1.7 months in the patient group. Corneal subbasal nerve density and corneal sensation were compared between groups at baseline and follow-up.Results
At baseline, the mean subbasal nerve density was significantly lower in both affected eyes (1.4?±?0.6?mm/mm2) and contralateral unaffected eyes (6.4?±?0.7?mm/mm2) compared with the controls (14.1?±?1.6?mm/mm2; all P?<?.001). At the end of follow-up, the mean nerve density in affected eyes increased to 2.8?±?0.7?mm/mm2 (P?=?.006), with no significant change in contralateral unaffected eyes (6.5?±?1.0?mm/mm2, P?=?.72). However, both eyes had lower nerve density than controls (all P?<?.001). Corneal sensation was significantly lower in affected eyes (2.6?±?0.6?cm) than in the control group (6.0?±?0.0, P?<?.001) and showed no significant change at the end of follow-up (2.5?±?0.6?cm, P?=?.80). Corneal sensation in contralateral unaffected eyes was not different in comparison with controls at both baseline and follow up (all p?>?.05).Conclusions
Our results demonstrate that although corneal nerve regeneration occurs in patients with HSV keratitis, this change is not clinically significant and does not results in changes of corneal sensation. Therefore, these patients need to be followed closely for complications of neurotrophic keratopathy and might benefit from neuro-regenerative therapies. 相似文献618.
Serial analysis of gene expression of lobular carcinoma in situ identifies down regulation of claudin 4 and overexpression of matrix metalloproteinase 9 下载免费PDF全文
619.
620.
Pedram Fadavi Amir Mohammad Arefpour Ramyar Hariri Maryam Vasheghani Maryam Garousi Farzad TaghizadehHesary 《Clinical Case Reports》2021,9(10)
Denosumab, a monoclonal antibody that specifically targets cytokine receptor activator of nuclear factor‐kappa B ligand (RANKL), is a potentially viable option in resistant aneurysmal bone cysts. 相似文献