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71.
OBJECTIVE: To evaluate the occurrence and prognostic significance of perineural invasion (PNI) in squamous cell carcinomas (SCC) of the oral cavity and oropharynx. STUDY DESIGN: A retrospective study of 101 patients with previously untreated SCC of the oral cavity and oropharynx was undertaken to evaluate the occurrence and prognostic significance of PNI in relation to local recurrence, regional recurrence, distant metastasis and survival. The logistic regression test was used for univariate and multivariate analyses. Actuarial survival curves were determined using the Kaplan-Meier method. RESULTS: PNI was present in 26 (25.7%) of 101 patients and was significantly associated with tumor differentiation, lymph node metastasis, and depth of invasion. Univariate analyses showed PNI was associated with local recurrence (P=.005), regional recurrence (P=.007), and distant metastasis (P=.013). In multivariate analysis, PNI was significantly associated with regional recurrence (P=.033) and distant metastasis (P=.021), but not with local recurrence (P=.109). The 5-year disease-specific survival for patients with and without PNI was 56.6% and 94.6%, respectively (P<.0001). CONCLUSION: PNI is an important predictor for outcome of patients with SCC of the oral cavity and oropharynx.  相似文献   
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Childhood histiocytosis is a rare and diverse group of proliferative disorders, characterized by accumulation and infiltration of antigen-presenting cells or antigen-processing cells, which can affect any tissue or organ. This study was performed in order to investigate the clinical characteristics of Iranian children with different types of histiocytic disorders. Thirty-five patients, with a median age of 3.5 years, who were referred and diagnosed with histiocytic disorders in a referral Children's Hospital in Iran from 1997-2006, were investigated in this study. According to the World Health Organization classification, 27 patients were in class 1, followed by 6 patients in class 2, and 1 patient in class 3. Moreover, 1 patient was diagnosed with sinus histiocytosis with massive lymphadenopathy. Bone lesions were the most common manifestation, which were detected in 15 cases, followed by skin lesions (11 cases) and fever (10 cases). Nonspecific findings like hepatomegaly and splenomegaly were found in 15 cases. Different types of treatment protocols were used according to the diverse groups of histiocytic disorders and different stages of disease, including surgical excision, radiotherapy, chemotherapy, and stem cell transplantation. Twelve patients did not respond well to the treatment and subsequently died due to complications of their disease. Although histiocytosis is considered a rare condition, it can be problematic for pediatric hematologists because of the unknown etiologies and pathogenesis, variable classifications and subtypes, diagnostic difficulties, poor therapeutic responses with high mortality, and some complications after different therapeutic protocols.  相似文献   
73.
Epidural hematoma is a potentially life threatening event that demands prompt diagnosis and surgical treatment, usually following head trauma. We present a case of a 9-year-old boy with no history of head trauma, and who was diagnosed with epidural hematoma secondary to frontal sinusitis; and the medical literature was reviewed.  相似文献   
74.
We present research on sunscreen use with possible pitfalls and discuss theory vs. reality. A literature review in PubMed was conducted using the terms ‘sunscreen application’, ‘sunscreen use’ and ‘sun protection factor’. The sun protection factor (SPF) of sunscreens are tested using a thickness of 2 mg/cm2, but investigations show that sunscreen under natural conditions is applied insufficiently with amounts about 0.39 to 1.0 mg/cm2, which decreases the protection factor considerably. It has been shown that early reapplication or use of very high SPF (70–100) may partly compensate for the discrepancy between the amounts of sunscreen applied during testing and in reality, and that sunscreen application can be improved by education of consumers. Missing areas and ultraviolet radiation exposure before sunscreen application are other pitfalls that reduce the protective effect of sunscreens considerably. Current sunscreen labelling overrates the protective effect of a given sunscreen when the reality of sunscreen use is taken into account. This may possibly mislead consumers to feel it is safe to extend sun exposure. Alternatively to educating people to use large amounts of sunscreen, we suggest a simple teaching strategy: (1) Apply before sun exposure and (2) Reapply once within 1 h.  相似文献   
75.
Cerebral ischemia is a condition in which there is insufficient blood flow to the brain to meet metabolic demand. This leads to cerebral hypoxia and thus to the death of neuronal cells or stroke. The limited number of medicines currently available for patients following ischemic stroke and insufficient data on efficiency of these chemicals in the treatment of stroke led us to the search for novel therapeutic approaches. Recent studies have focused on the possible capacity of natural compounds extracted from vegetables and fruits, to prevent human disabilities caused by cerebral ischemia. In this review, we will discuss some plants and their constituents that may protect brain ischemia or delay the neurological disorders following a stroke. We have reviewed different studies in scientific databases that investigate herbal compounds and their effects on cerebral ischemia. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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Flexible PVC/BT (Polyvinyl chloride/Barium Titanate) composite thick films with (0–30%) volume fractions of BaTiO3 were fabricated via the solution casting method. The effects of BaTiO3 filler on the phase, microstructure and dielectric properties of composite films were investigated. The XRD results revealed that BT particles are embedded in the PVC matrix with no chemical reaction taking place between the two phases. It was observed that the glass transition temperature of PVC had increased with the addition of BT. The frequency dispersion in the dielectric constant versus temperature curves indicated the relaxor nature of the composites. The dielectric constant (εr) measured at 40 °C, increased from 7.6 for pure PVC to 16.1 for 30% of BaTiO3 content in PVC polymer matrix. It is suggested that BaTiO3 ceramic powder enhanced the dielectric properties of PVC and may be used as a flexible dielectric material.  相似文献   
80.
Abstract

Among several forms of miseries experienced by cancer patients, one of the significant experiential problems is the inevitable fear of death. The present study aimed at exploring the relationship between death anxiety, perceived social support, and different demographic variables. A sample of 80 breast cancer patients was recruited from different departments of oncology in Pakistan. Research findings revealed that death anxiety was negatively associated with social support. Moreover, it was found that education and marital status were associated with death anxiety among patients with breast cancer. Results suggest that social support assist in reducing death anxiety and enhance their recovery course.  相似文献   
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