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BACKGROUND: Asthma and rhinitis often coexist, and there is evidence to suggest that they have similar histopathologic features. OBJECTIVE: To examine whether the inflammatory infiltration in the nasal mucosa in rhinitis is affected by the presence of asthma and allergy. METHODS: Nasal mucosa biopsy samples were collected from 44 individuals: 18 with rhinitis and asthma (9 allergic and 9 nonallergic), 16 with rhinitis and no asthma (8 allergic and 8 nonallergic), and 10 nonallergic control subjects. The alkaline phosphatase-anti-alkaline phosphatase method was applied to 6-microm-thick cryostat sections using monoclonal antibodies against T cells (CD4 and CD8) and eosinophils (EG2). Slides were counted blindly, and results are expressed as cells per high-power field. RESULTS: Eosinophil counts were higher in the nasal mucosa of rhinitic patients vs controls. No differences in cellular infiltration were detected between rhinitic patients with and without asthma or between allergic and nonallergic patients. A trend toward higher CD4+ T-cell counts in the nasal mucosa of rhinitic patients was observed, whereas no differences were noted in CD8+ T-cell infiltration among the groups. CONCLUSION: Inflammatory infiltration, characterized by the presence of eosinophils and CD4+ T cells, was similar in the nasal mucosa in noninfectious rhinitis irrespective of the presence of asthma or the allergic status of the patient.  相似文献   
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Classical evolutionary theory predicts the existence of genes with antagonistic effects on longevity and various components of early-life fitness. Quantitative genetic studies have provided convincing evidence that such genes exist. However, antagonistic pleiotropic effects have rarely been attributed to individual loci. We examine several classes of longevity-assurance genes: those involved in regulation of the gonad; the insulin-like growth factor pathway; free-radical scavenging; heat shock proteins and apoptosis. We find initial evidence that antagonistic pleiotropic effects are pervasive in each of these classes of genes and in various model systems--although most studies lack explicit studies of fitness components. This is particularly true of human studies. Very little is known about the early-life fitness effects of longevity loci. Given the possible medical importance of such effects we urge their future study.  相似文献   
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The examination of the moment exerted by the hamstrings during maximum isokinetic knee extensor tests is useful when comparing isokinetic strength and muscle activity patterns between children and adults. The purpose of this study was to examine the effect of antagonist moment of the hamstrings on the isokinetic moment of the knee extensors in pubertal children and to determine whether this effect is altered following a fatigue task. Eighteen healthy pubertal males [age 14.3 (0.5) years] performed 34 maximal isokinetic concentric efforts of the knee extensors at 60°·s−1. The average moment of force and electromyographic (aEMG) signal of vastus medialis (VM), vastus lateralis (VL) and biceps femoris (BF) at 11–30°, 31–50°, 51–70° and 71–90° of knee flexion were calculated for each repetition. The hamstrings antagonist moment was determined before and after the fatigue task by fitting the aEMG–moment relationship at different levels of muscle effort using second-degree polynomials. The percentage contribution of the antagonist moment to the resultant joint moment ranged from 7.1 % to 60.4 % throughout the range of motion, with the highest percentage observed close to full knee extension (11–30°). The antagonist effect was significantly greater during concentric tests of the knee extensors compared to the corresponding eccentric tests (p<0.05). Following the fatigue test, there was an overall decline of the resultant joint moment, but no changes in the predicted hamstrings moment were observed. These results indicate that when testing maximal knee extensor isokinetic strength in pubertal boys, activity of the hamstrings implies a reduction of the net extensor moment as compared to the isolated capacity of the knee extensors. However, this antagonist effect is not altered following the performance of an isokinetic fatigue knee extension task. Electronic Publication  相似文献   
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Gravieras are ‘gruyere’ type hard cheeses with a variety of different products and the second highest consumption in Greece. In this study, we present a dietary intake assessment and a nutritional characterization of pre-packed graviera products sold in the Greek market using Nutri-Score Front of Pack Label (FoPL). The nutrient contents of 92 pre-packed graviera products were combined with daily individual consumption data extracted from the Hellenic National Nutrition Health Survey (n = 93), attempting to evaluate the contribution of graviera’s consumption to the Greek diet. The analysis of nutrients’ intake as a Reference Intake (RI) percentage ranked saturated fat first on the nutrients’ intake list, with RI percentage ranging from 36.1 to 109.2% for the 95th percentile of consumption. The respective % RI for energy, total fat, carbohydrates, sugars, proteins and salt ranged from 12.7–20.7%, 21.6–50.4%, 0–3.1%, 0–6.1%, 37–57.1% and 6.3–42%. Nutri-Score classified 1% of the products to C—light orange class, 62% to D—orange and 37% to E—dark orange, while no products were classified to A—dark green or B—green classes. The comparison between the Nutri-Score classification and the nutrients’ intake assessment, also separately conducted within the classes, showed a higher salt intake after the consumption of products classified as D—orange and E—dark orange.  相似文献   
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Background: The gastrointestinal tract is the most common site of extranodal involvement in non-Hodgkin's lymphoma (NHL). Primary colorectal NHL comprises 13–18% of all gastrointestinal NHL but is not commonly reported as a separate entity. Methods: This was a retrospective review of the medical records of 19 patients over a 16-year period to evaluate the clinical features and behavior of colorectal NHL. Results: A pediatric group of seven male patients presented at an early stage with acute symptomatology. The primary tumor was located in the ileocecum in all cases and intussusception was common. An adult group of 12 patients presented at a later stage with chronic symptomatology. Staging study results were positive by bone marrow biopsy in four of 16 patients (25%), by lymphangiography in six of 11 patients (54.5%), and by gallium scan in eight of 10 patients (80%). Seven patients relapsed a median of 8 months after treatment. Three other patients died during treatment, one died of other causes, and one died without receiving treatment. The remaining seven patients are alive from 41 to 231 months without evidence of disease. Five of these patients are in the pediatric group, where the median survival was >72 months. The overall median survival was 45 months. Conclusion: Colorectal NHL is a disease that affects both the pediatric and adult population. Although pediatric patients have an excellent prognosis with anticipated long-term survival after treatment, long-term survival can be expected in 50% of adult patients. In both groups of patients, multimodality therapy with surgery, chemotherapy, and radiation is the treatment of choice.Presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993.  相似文献   
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The mammalian cerebral cortex, although a structure of greatcomplexity, is characterized by a high degree of organizationwhere the proportions, spatial relationships, and propertiesof the various cell types are rigidly controlled. The mechanismsresponsible for the creation of such a rigid distribution ofcell types are not known. Lineage studies in adult rats havesuggested that each of the cortical progenitor cells liningthe telencephalic ventricles during embryonic development givesrise to progeny of the same phenotype (homogeneous clones).However, the possibility that homogeneous clones are the resultof complex processes affecting both the final number and thephenotype of clonally related cells during development has notbeen investigated. In the present study, we followed the developmentof cortical cell lineages labeled with retroviral injectionsat embryonic day (E) 16 in rats of 7, 14, or 21 d of age usingelectron microscopy and immunocytochemistry for the neurotransmittersglutamate and GABA. We found that a significant number of corticalclones at postnatal day (P) 7 and P14, and fewer at P21, showedmixed pyramidal/nonpyramidal cell composition. We sometimesobserved that "mixed" neuronal clones contained cells immunoreactivefor both glutamate and GABA. In the general population of corticalcells, "bireactive" neurons represented 3.7% of all neuronsat P7, 1.8% at P14, and 0.6% in adult rats. Although the changein the composition of neuronal clones between the third weekof postnatal life and adulthood may be due to changes in thephenotype of some developing neurons, we would like to suggestthat it is probably due to selective neuronal cell death.  相似文献   
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