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911.
BACKGROUND AND OBJECTIVES: Interleukin (IL)-23 is a key regulator of inflammation and influences the activities of T-helper 17 (Th-17) lymphocytes. Recent reports indicate that variants in the gene coding for its receptor (IL-23R) are strongly associated with Crohn's disease (CD). We investigated whether DNA variants in the IL-23R gene determine susceptibility for CD in Canadian children. DESIGN AND METHODS: A case-control and case-parent trio design was implemented at three pediatric centers across Canada. Cases of CD (相似文献   
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Ischemic bowel disease results from an acute or chronic drop in the blood supply to the bowel and may have various clinical presentations, such as intestinal angina, ischemic colitis or intestinal infarction. Elderly patients with systemic atherosclerosis who are symptomatic for the disease in two or more vascular beds have multiple comorbidities and are particularly at risk. The clinical evolution and outcome of this disease are difficult to predict because of its pleomorphic aspects and the general lack of statistical data. In this paper, we present the case of a patient who was monitored in our unit for six years. For this patient, we encountered iterative changes in the clinical pattern, beginning with chronic “intestinal angina” and finishing with signs of acute mesenteric ischemia after an episode of ischemic colitis. This evolution is particularly rare in clinical practice, and the case is instructive because it raises discussions about the natural history of the condition and the therapeutic decisions that should be made at every stage of the disease. An important lesson is that ischemic bowel disease should always be considered in patients who have multiple risk factors for atherosclerosis and have experienced recurrent “indistinct” abdominal symptoms. In these cases, aggressive investigation and therapeutic decisions must be taken whenever possible. Despite an absence of standardized protocols, angiographic evaluation and revascularization procedures have beneficial outcomes. Current advances in endovascular therapy, such as percutaneous transluminal angioplasty with stenting, should be increasingly used in patients with chronic mesenteric ischemia. Such therapy can avoid the risks that are associated with open repair. However, technical difficulties, especially in severe stenotic lesions, frequently occur.  相似文献   
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Previous neuroimaging studies suggest a negative relationship between the apolipoprotein (ApoE) ε4 allele and brain integrity in human immunodeficiency virus (HIV)-infected (HIV+) individuals, although the presence of this relationship across adulthood remains unclear. The purpose of this study is to clarify the discrepancies using a large, diverse group of HIV+ individuals and multiple imaging modalities sensitive to HIV. The association of ApoE ε4 with structural neuroimaging and magnetic resonance spectroscopy (MRS) was examined in 237 HIV+ individuals in the CNS HIV Anti-Retroviral Therapy Effects Research (CHARTER) study. Cortical and subcortical gray matter, abnormal and total white matter, ventricles, sulcal cerebrospinal fluid (CSF), and cerebellar gray matter, white matter, and CSF volumes, and MRS concentrations of myo-inositol, creatine, N-acetyl-aspartate, and choline in the frontal white matter (FWM), frontal gray matter (FGM), and basal ganglia were examined. Secondary analyses explored this relationship separately in individuals ≥50 years old (n?=?173) and <50 years old (n?=?63). No significant differences were observed between ApoE ε4+ (ApoE ε3/ε4 and ApoE ε4/ε4) individuals (n?=?69) and ApoE ε4? (ApoE ε2/ε3 and ApoE ε3/ε3) individuals (n?=?167). When individuals were further divided by age, no significant genotype group differences were identified in individuals <50 or ≥50 years of age on any neuroimaging outcome. The ApoE ε4 allele did not affect brain integrity in this large, diverse sample of HIV+ individuals. The effects of ApoE ε4 may not be apparent until more advanced ages and may be more prominent when present along with other risk factors for neuronal damage.  相似文献   
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This paper aims to carry out measurements of indoor air temperature, relative humidity and carbon dioxide (CO2) concentrations as well as to determine CO2 production by students and teacher during various physical activities. Two classrooms of Technical University of Kosice were selected for the research. Results of objective measurements confirmed strong correlation between CO2 concentration occupancy for all measurements. Recommended value for indoor CO2 level according to Pettenkofer (1,000 ppm) was exceeding in 60.9%. Results of this study showed the insufficient ventilation intensity in classrooms as well as obvious rise of CO2 concentration during the exams. The highest increase of CO2 was recorded during harder physical activity (run on the spot, squats, right and left side lunges, and rotating of the hips). Regarding CO2 production by respondents it can be see that it is visibly increased with increasing physical activity.  相似文献   
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Bovine babesiosis is a tick‐transmitted haemoparasitic disease caused by Babesia bovis and B. bigemina affecting cattle of tropical and subtropical regions around the world. Pathogens are transmitted by the tick vector Rhipicephalus microplus displaying a widespread distribution in northeastern Argentina. The disease is characterized by significant animal morbidity and mortality resulting in considerable economic loss. In this study, B. bovis and B. bigemina infection was investigated in a cattle herd of 150 adult bovines of pure Braford breed raised in a tick‐hyperendemic field using molecular and serum antibody tests. A highly sensitive nested polymerase chain reaction (nPCR) assay targeting a species‐specific region of the apocytochrome b gene resulted in direct B. bovis and B. bigemina detection in 27.3% and 54.7% of bovines, respectively. A recently developed immunochromatographic strip test (ICT) based on recombinant forms of spherical body protein 4 and the C‐terminal region of rhoptry‐associated protein 1 showed that 71.3% and 89.3% of bovines were seropositive for B. bovis and B. bigemina, respectively. The mixed infection rate as observed by direct (19.3%) and indirect detection (65.3%) coincided with those expected, respectively. Importantly, four months after sampling, nine bovines of the studied herd showed clinical signs of bovine babesiosis of which six animals eventually died. Microscopic detection of infected erythrocytes in Giemsa‐stained blood smears confirmed B. bovis infection. Our study demonstrates that although animals showed a relatively high and very high rate of immunity against infection with B. bovis (71.3%) and B. bigemina (89.3%) parasites, respectively, clinical cases and fatalities due to the infection with B. bovis were observed. It is proposed that the most adequate control measure in the studied epidemiological situation is to vaccinate animals to prevent losses and/or an outbreak of bovine babesiosis.  相似文献   
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