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1.
In medical studies with censored data Kaplan and Meier's product limit estimator has frequent use as the estimate of the survival function. Simultaneous confidence intervals for the survival function at various time points constitute a useful addition to the analysis. This study compares several such methods. We consider in a simulation investigation two whole curve confidence bands and four methods based on the Bonferroni inequality. The results show that three Bonferroni-type methods are essentially equivalent, all being better than the other methods when the number of time points is small (3 or 5). 相似文献
2.
Hussein MR Hassan HI Hofny ER Elkholy M Fatehy NA Abd Elmoniem AE Ezz El-Din AM Afifi OA Rashed HG 《Journal of clinical pathology》2005,58(2):178-184
BACKGROUND: Systemic sclerosis (SSc) is a multisystem disease with underlying immune mechanisms. AIMS: To investigate the clinicopathological characteristics of the lesions; immunological alterations in the bronchoalveolar lavage fluid (BALF), peripheral blood, and skin; and correlations between the clinicopathological characteristics and immunological alterations in SSc. MATERIALS/METHODS: Skin biopsies, BALF, and peripheral blood samples were obtained from 19 patients (18 women, one man) with SSc and six age and sex matched healthy controls (HCs). Mononuclear inflammatory cells (MICs), CD4/CD8 cells, tumour necrosis factor alpha (TNFalpha), and interleukin 1beta (IL1-1beta) concentrations were examined in all samples using histological methods, enzyme linked immunosorbent assay, and immunoperoxidase staining. RESULTS: The mean (SD) age of the patients with SSc was 34.8 (2.6) years. Proteinuria, positive rheumatoid factor, and C reactive protein were seen in 15.8%, 26.3%, and 26.3% of patients, respectively. Compared with HCs, there were significantly higher: total MICs (macrophages, lymphocytes), neutrophils, and eosinophils in BALF, blood, and skin (all p<0.05); cytokine concentrations in BALF (TNFalpha, p<0.001; IL-1, p<0.01) and peripheral blood (p<0.01 and p<0.05); and CD8/CD4+ T cells in peripheral blood (p<0.05). Compared with HCs, lesional skin had significantly higher histiocyte cell counts (p<0.05), lower lymphocyte counts (p<0.05), and higher CD4/CD8 ratios (p<0.001). There were significant correlations between cytokine concentrations and CD8+ T cells and forced vital capacity (p<0.001 and p<0.01, respectively). CONCLUSIONS: MICs, CD4/CD8+ cells, and cytokines are altered in SSc. These alterations correlated with the underlying disease process and therefore may have pathogenic, modulatory, and potential prognostic roles in SSc. 相似文献
3.
T. Gaafar S. Ismail M. Helmy A. Afifi N. Guirguis R. El Ridi 《Parasitology research》1993,79(2):103-108
Schistosoma haematobium soluble egg antigens (SH SEAs) induce intense granulomas in human hosts that often culminate in severe disease. In an attempt to identify the SH SEA fractions that are responsible for pathology, we combined T-cell Western blotting and an in vitro model of granuloma formation. Whole SH SEAs were dotted onto nitrocellulose pieces or were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electrotransferred onto nitrocellulose paper. Horizontal strips bearing the separated antigens were solubilized in dimethylsulfoxide and precipitated in carbonate/bicarbonate buffer. Antigen-free and antigen-bearing particles were used to stimulate peripheral blood mononuclear cells (PBMCs) obtained fromS. haematobium-infected patients and sex- and agematched healthy controls to form granulomas in vitro. Whole SH SEA-bearing nitrocellulose particles elicited in vitro formation of granulomas by PBMCs from infected donors. The response was similar in sensitivity, specificity, and reproducibility to that evoked by SH SEA-bound polyacrylamide beads. The results obtained in samples from 30 patients and 10 controls tested with SH SEA-separated fractions revealed that SEA bands of 84 000, 63 000, 57 000, 55 000, 40 000, 30 000, and 28 000 Da elicited in vitro granuloma reactions by PBMCs of almost all infected patients. Conversely, separated soluble adult-worm antigens failed to stimulate PBMCs of infected patients to form granulomas. This study is the first to identify the SH SEA fractions that evok in vitro granuloma formation and represents an initial step toward the development of an anti-urinary schistosomiasis pathology vaccine. 相似文献
4.
5.
A case of a woman who underwent removal of a breast implant consistent with a polyvinyl sponge contained within a polyethylene bag is described. The use of the polyvinyl alcohol sponge as a breast implant virtually ceased in the mid 1960s with the introduction of silicone gel breast prostheses. However, it is still possible that the plastic surgeon may encounter a patient with one of these sponge implants in place. Thus, it is important for the plastic surgeon to be aware of their existence, natural history, and potential late complications. In addition, since the removal of silicone from general use for augmentation mammaplasty, there have been intense efforts to identify new filler materials for use in breast implants. Polyvinyl alcohol has been considered a possible material. There is a paucity of information in the recent literature pertaining to the characteristics and use of polyvinyl alcohol sponge implants. Therefore, this report describes a patient treated 38 years following placement of this type of implant and reviews the literature. 相似文献
6.
7.
BACKGROUND: It is known that exertion can aggravate migraine headache. However, the relationship between exertion and migraine aura is unknown. OBJECTIVE: To study the relationship between exertion and migraine aura. DESIGN: Case report. SETTING: Tertiary care hospital. PATIENT: A 67-year-old man presented with recurrent attacks of exertion-induced hemiplegic migraine. Since the hemiparetic attacks were exertion induced, they were initially ascribed to recurrent transient ischemic attacks. However, the clinical picture, normal findings on cerebral angiography and neuroimaging (during the period of hemiparesis), lack of response to treatment with antiplatelets and anticoagulants, and successful treatment with verapamil suggested that the hemiparesis was not due to ischemia, but was indeed a migraine aura. We suggest that exertion induced the aura of hemiparesis by lowering the threshold for the development of cortical spreading depression. Even though our patient had no family history of hemiplegic migraine, a mutation in an ion channel gene (eg, the CACNA1A gene on chromosome 19) might account for his episodic attacks. CONCLUSION: Migraine aura should be included in the differential diagnosis of exertion-induced focal neurologic deficit. 相似文献
8.
A. Afifi Y. Bouabdallah F. Ettaybi M. Benhammou 《Journal de Pédiatrie et de Puériculture》2006,19(8):328-330
Hydrocolpos is characterized by a vaginal accumulation of cervical and vaginal secretions. It often occurs in newborn child and infant. Imperforate hymen is frequently associated; in rare instances, complete higher vaginal diaphragm or partial vaginal atresia is diagnosed. Hydrocolpos can be treated by hymenectomy using imperforate hymen. Because of additional malformation, the treatment can be more complex for vaginal obstruction. The authors report a series of four patients with hydrocolpos: three neonates and one 2-month old infant. Ultrasonography confirmed the physical findings. Three patients with imperforate hymen underwent hymenectomy in X. The fourth which had a virginal atresia and pyocolpos drainage was treated using celioscopy. The three first patients outcome was favorable except for the patient with pyocolpos who died with septicemia. 相似文献
9.
Gelan M. Salem Wafik M. El-Sheik Basma G. El-shanawany Khaled H. Afifi 《Neurosciences (Riyadh, Saudi Arabia)》2021,26(2):179
Objectives:To assess low dose altepase outcome and safety in comparison with a standard-dose regimen for acute ischemic stroke treatment in Egyptian patients.Materials:An observational prospective cohort non-randomized single blinded study was carried out during the period from November 2017 to December 2018. Eighty Egyptian acute ischemic stroke patients, all eligible for intravenous alteplase, were subdivided into 2 groups (40 patients in each group). Patients were thrombolysed at a dose of 0.6 mg/kg in the first group and 0.9 mg/kg in the second group. Both groups were compared in regard to safety and outcome. Safety was expressed by the rate of symptomatic intracranial hemorrhage (SICH) and 3 months mortality, while outcome was expressed by favorable outcomes at three months (modified Rankin Scale [mRS] of 0 to 2).Results:In the first group, 69.2% (n=27) achieved favorable outcomes at 90 days compared with 64.1% (n=25) in the second group (p=0.631). Ninety-day mortality was 5% (n=2) in the first group versus 2.5% (n=1) in the second group (p=0.556). Symptomatic intracranial hemorrhage was noted in 3 patients in the second group and zero patients in the first group (p=0.077).Conclusion:Low-dose alteplase could be a practical alternative for Egyptian populations with acute ischemic stroke especially in 3 to 4.5 hours window.Cerebrovascular stroke is the second death and the seventh disability leading cause worldwide.1 Tissue-type plasminogen activator (tPA) alteplase was the first medication approved by the Food and Drug Administration (FDA) for the acute ischemic stroke (AIS) treatment on June 1996, within 3 hours of stroke onset with a recommended dose of 0.9 mg/kg (maximum 90mg).2 In 2008, the safety of using alteplase within 3 to 4.5 hours of stroke onset was approved by the Safe Implementation of Treatments in Stroke International Stroke Thrombolysis Registry (SITS -ISTR)3 and the European Cooperative Acute Stroke Study (ECASS III).4 However, thrombolytic therapy use has not been widely adopted, especially in developing countries. The restricted time window (3 to 4.5 hours), intracerebral hemorrhage (ICH) risk and the drug high cost are major obstacles preventing its broad application.5 Coagulation and fibrinolysis responses differ among different races, which increase symptomatic intracerebral hemorrhage (SICH) risk with standard-dose alteplase6 in Asian populations, many Asian neurologists considered alteplase low dose to be a better alternative for ischemic stroke treatment. Many studies had been conducted in order to prove the efficacy and safety of Alteplase low dose.7-9 One of these studies was the Japan Alteplase Clinical Trial (J-ACT) conducted by Yamaguchi et al10 According to this study, using a 0.6 mg/kg dose of intravenous recombinant tissue plasminogen activator (rtPA) in Japanese patients was safe and effective. Despite the relatively stroke high rate among Egyptian populations, 963/100,000 inhabitants, only less than 1% of stroke patients receive intravenous thrombolysis. A major reason for this is the drug cost.11,12 Low-dose regimens (0.6 mg/kg) use will lower the economic burden of thrombolytic therapy in the community and will greatly promote the implementation of this therapy in Egypt. Our study aim was to assess the outcome and safety of alteplase low dose in comparison to the standard-dose regimen in AIS treatment in Egypt. 相似文献
10.
Lena Friedrich Faik K. Afifi Jiri Skarvan Niklaus F. Friederich Michael T. Hirschmann 《Knee surgery, sports traumatology, arthroscopy》2012,20(10):1978-1982
A case of an 18-year-old gardener who sustained an anterior–superior dislocation of the sternoclavicular joint while playing handball and falling on his right shoulder is presented. Non-surgical treatment failed, and the patient could willingly dislocate the right clavicle while abduction and external rotation of the arm. This painful condition was finally treated with surgical reconstruction of the sternoclavicular joint using gracilis tendon autograft and repair of the discus. Level of evidence Therapeutic study, case report and technical note, Level IV. 相似文献