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BACKGROUND: Chronic pulmonary disease and progressive tissue hypoxia are major causes of morbidity and mortality in cystic fibrosis (CF). Normally the body adapts to tissue hypoxia by increasing the red cell mass and decreasing the Hb-O(2) affinity. These adaptations are commonly observed in patients with cyanotic heart disease and individuals living at high altitude. However, patients with CF not only have an impaired erythroid response to hypoxia, but also are frequently anaemic. METHODS: In order to evaluate erythroid marrow activity and tissue oxygenation in 37 patients with CF we measured: the haematological and blood chemistry parameters; including red cell indices, ferritin, erythropoietin (Epo) and soluble transferrin receptors (sTfR) levels; arterial blood gases, P(50) and oxygen release to the tissues (O(2)(R)) and the 2,3-BPG levels. RESULTS: The main results showed that a) patients with CF have a mild degree of tissue hypoxia which is expressed by the moderately decreased of P(50) and O(2)(R) values and the relative increase of Epo level, b) 2,3-BPG synthesis in patients with CF is normal and c) sTfR levels are significantly increased (3-fold normal) in patients with CF compared to normal controls. CONCLUSIONS: The above observations indicate that erythroid marrow activity in patients with CF is increased.  相似文献   
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The neuronal morphological development of the avian telencephalic cortex (DMC) is studied in Golgi-stained brain sections. The neuronal types at embryonic days 10, 13, 16, as well as of newborn chick are identified. The immature neurons are characterized by the presence of hair-like processes, growth cones and dendritic varicosities. These characteristics are absent in neuronal types of newborn chick. There are five patterns of differentiation, which produce six neuronal types in the newborn chick: horizontal neurons, pyramidal neurons, bipyramidal neurons, short axon multipolar neurons, long axon multipolar neurons and periventricular neurons. The morphological features of migrating embryonic cells are described. The dendritic spines appear in 16-day embryos in the majority of neuronal types.  相似文献   
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This case report demonstrates how extracting a maxillary deciduous canine affects the eruption path of a labially displaced ectopically erupting permanent canine. A long-term follow-up is presented, and the biologic mechanisms are discussed.  相似文献   
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A total of 186 blood samples from 24 HIV-1 seropositive hemophiliac patients, monitored every four months for 29 months, were investigated for the presence of viral antigen in plasma. In addition, peripheral blood mononuclear cells (PBMC) were cultured for HIV-1, using normal PBMC as a target for replication. Antigenemia was detected in 51 % of the patients and from PBMC in 87.5 % of the patients. The incidence of HIV isolation in asymptomatic patients (42.8 %) was similar to that found in symptomatic patients (51.4 %). Patients with opportunistic infections had a higher incidence of lymphocytic viremia (p<0.05). Plasma viremia was closely associated (p<0.05) with low CD4+ counts and infection progression. The persistence of antigenemia was also a marker of a poor clinical course. In treated patients, plasma viremia was the marker that better correlated with the clinical course, and it did not appear during the first nine months of therapy. Zidovudine doses of >500 mg/day significantly lowered the appearance of antigenemia and lymphocytic viremia (p<0.05).  相似文献   
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Pulmonary tuberculosis associated with membranous nephropathy   总被引:1,自引:0,他引:1  
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