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61.
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Helicobacter pylori and the prevention of gastric cancer.   总被引:2,自引:0,他引:2  
BACKGROUND: Helicobacter pylori is an important cause of stomach cancer that infects a substantial proportion of the Canadian adult population. H pylori can be detected by noninvasive tests and effectively eradicated by medical treatment. Screening for and treatment of H pylori may represent a significant opportunity for preventive oncology. METHODS: Cancer Care Ontario organized a workshop held in Toronto, Ontario, on October 24 and 25, 2002, to: review the current state of knowledge regarding H pylori treatment and cancer prevention; determine if there is currently sufficient evidence to consider the promotion of H pylori treatment for the purpose of cancer prevention; identify critical areas for research; and advise Cancer Care Ontario on H pylori and cancer prevention. RESULTS: Workshop participants developed a number of recommendations for research into the relationship between H pylori and stomach cancer, including determining the prevalence of infection in different regions of Canada, the pathogenetic sequence of carcinogenesis from H pylori infection, and the implementation of a prospective observational study. INTERPRETATION: Although the rate of H pylori infection is declining in Canada and the treatment of H pylori is generally accepted to be safe, the evidence to date may not warrant the implementation of population screening for H pylori infection to prevent gastric carcinoma in average-risk populations. Rather, a demonstration project is needed to estimate prevalence, evaluate the merits of screening, measure patient compliance and physician participation, develop education materials, establish a registry for monitoring and evaluation, and develop a quality assurance framework.  相似文献   
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Over the last 7 years we have seen more than 200 severe aplastic anemia patients at this centre. Three of them developed an unusual complication in the form of thymic hemorrhage. Following this complication, all 3 patients recovered partially from their aplastic anemia, without any need for further immunosuppression. These cases show possible ways to manipulate the thymus gland as a management strategy for this disease.  相似文献   
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Dietary and waterborne exposure to copper oxide (CuO) and zinc oxide (ZnO) nanoparticles (NPs) was conducted using a simplified model of an aquatic food chain consisting of zooplankton (Artemia salina) and goldfish (Carassius auratus) to determine bioaccumulation, toxic effects, and particle transport through trophic levels. Artemia contaminated with NPs were used as food in dietary exposure. Fish were exposed to suspensions of the NPs in waterborne exposure. ICP‐MS analysis showed that accumulation primarily occurred in the intestine, followed by the gills and liver. Dietary uptake was lower, but was found to be a potential pathway for transport of NPs to higher organisms. Waterborne exposure resulted in about a 10‐fold higher accumulation in the intestine. The heart, brain, and muscle tissue had no significant Cu or Zn. However, concentrations in muscle increased with NP concentration, which was ascribed to bioaccumulation of Cu and Zn released from NPs. Free Cu concentration in the medium was always higher than that of Zn, indicating CuO NPs dissolved more readily. ZnO NPs were relatively benign, even in waterborne exposure (p ≥ 0.05). In contrast, CuO NPs were toxic. Malondialdehyde levels in the liver and gills increased substantially (p < 0.05). Despite lower Cu accumulation, the liver exhibited significant oxidative stress, which could be from chronic exposure to Cu ions. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 119–128, 2015.  相似文献   
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Cardiovascular Drugs and Therapy - Duchenne muscular dystrophy (DMD) is associated with a progressive alteration in cardiac function. The aim of this study was to detect early cardiac dysfunction...  相似文献   
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Background:

Asphyxia is considered an important cause of morbidity and mortality in neonates. This condition can affect many vital organs including the central nervous system and may eventually lead to death or developmental disorders.

Objectives:

Considering the high prevalence of asphyxia and its adverse consequences, the present study was conducted to evaluate the risk factors for birth asphyxia and assess their correlation with prognosis in asphyxiated infants.

Patients and Methods:

This two-year follow-up cohort study was conducted on 260 infants (110 asphyxiated infants and 150 healthy neonates) at Mashhad Ghaem Hospital during 2007 - 2014. Data collection tools consisted of a researcher-designed questionnaire including maternal and neonatal information and clinical/laboratory test results. The subjects were followed-up, using Denver II test for 6, 12, 18, and 24 months (after discharge). For data analysis, t-test was performed, using SPSS version 16.5. P value ≤ 0.05 was considered statistically significant.

Results:

Of 260 neonates, 199 (76.5%) and 61 (23.5%) cases presented with normal neonatal outcomes and with abnormal neonatal outcomes (developmental delay), respectively. Variables such as the severity of asphyxia (P = 0.000), five-minute Apgar score (P = 0.015), need for ventilation (P = 0.000), and severity of acidosis at birth (P = 0.001) were the major prognostic factors in infants with asphyxia. Additionally, prognosis was significantly poorer in boys and infants with dystocia history (P = 0.000).

Conclusions:

Prevalence of risk factors for developmental delay including the severity of asphyxia need for mechanical ventilation, and severity of acidosis at birth, dystocia, and Apgar score were lower in surviving infants; therefore, controlling these risk factors may reduce asphyxia-associated complications.  相似文献   
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Reproducing the features of the extracellular matrix is important for fabricating three‐dimensional (3D) scaffolds for tissue regeneration. A collagen‐like polypeptide, poly(Pro‐Hyp‐Gly), is a promising material for 3D scaffolds because of its excellent physical properties, biocompatibility, and biodegradability. In this paper, we present a novel photocrosslinked poly(Pro‐Hyp‐Gly) hydrogel as a 3D scaffold for simultaneous rat bone marrow stromal cell (rBMSC) encapsulation. The hydrogels were fabricated using visible‐light photocrosslinking at various concentrations of methacrylated poly(Pro‐Hyp‐Gly) (20–50 mg/ml) and irradiation times (3 or 5 min). The results show that the rBMSCs encapsulated in the hydrogels survived 7 days of incubation. Calcium deposition on the encapsulated rBMSCs was assessed with scanning electron microscope observation, Alizarin Red S, and von Kossa staining. The most strongly stained area was observed in the hydrogel formed with 30 mg/ml of methacrylated poly(Pro‐Hyp‐Gly) with 5‐min irradiation. These findings demonstrate that poly(Pro‐Hyp‐Gly) hydrogels support rBMSC viability and differentiation, as well as demonstrating the feasibility of using poly(Pro‐Hyp‐Gly) hydrogels as a cytocompatible, biodegradable 3D scaffold for tissue regeneration.  相似文献   
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