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21.
The effects of glucocorticoids on the proportion of lymphocytes in bronchoalveolar lavage (BAL) fluid in relation to humoral and cellular immunity were studied in 56 patients with steroid-dependent intractable asthma. To analyze the mechanism responsible for reduced numbers of BAL lymphocytes, we divided the subjects into 4 groups according to their BAL lymphocyte proportions: 0—4.9%, 5.0-9.9%, 10.0-14.9%, and 15.0-20.0%. Serum IgG levels and the peripheral lymphocyte count were significantly reduced in patients with a low proportion of BAL lymphocytes (less than 9.9%) than in those with more than 10% BAL lymphocytes. Delayed cutaneous reactivity to purified protein derivative was suppressed in patients with a low proportion of BAL lymphocytes (less than 4.9%). The mean proportion of BAL neutrophils tended to increase as the proportion of BAL lymphocytes decreased. These results show that the reduction in BAL lymphocytes produced by glucocorticoids is associated with suppressed humoral and cellular immunity, and that under such conditions the proportion of BAL neutrophils increases.  相似文献   
22.
The effects of long-term glucocorticoid therapy on airway inflammation were examined in 84 asthma patients. The proportion of lymphocytes in bronchoalveolar lavage (BAL) fluid was significantly decreased in patients with steroid-dependent intractable asthma (SDIA) compared to results in non-SDIA patients, while BAL neutrophils were significantly increased in SDIA patients compared to results in non-SDIA patients. Regarding age, in patients under the age of 69 (except those between 30 and 39), BAL lymphocyte number was significantly decreased in SDIA compared with non-SDIA subjects, and in patients between 50 and 69, BAL neutrophils were significantly increased in SDIA compared with non-SDIA subjects. The number of BAL lymphocytes was significantly lower in patients with serum cortisol levels of less than 5.0 μg/dl than in those with levels of more than 5.1 μg/dl. BAL lymphocyte number was also significantly lower in patients who had received glucocorticoid therapy for more than 6 years than in those who had received such therapy for 2 years. These results show that long-term glucocorticoid therapy decreases the number of lymphocytes and increases neutrophil numbers in the airways.  相似文献   
23.
Our recent studies have demonstrated that the middle domain of N-acetyl-D-glucosamine (GlcNAc) 2-epimerase participates in the specificity for and binding of nucleotides. To identify the residue conferring nucleotide binding, amino acid substitutions were introduced in the human and rat GlcNAc 2-epimerases. The mutational analyses indicate that residue 171 of GlcNAc 2-epimerase is critical for the nucleotide binding of GlcNAc 2-epimerase.  相似文献   
24.
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) affects the thyroid morphologically and/or functionally in adult animals. Recently, the National Toxicology Program conducted a 2-year gavage study of TCDD in female Harlan Sprague-Dawley rats. The only treatment-related alterations found in thyroid follicles were decreased luminal size and increased height of the follicular epithelial cells, without prominent protrusion into the lumen. The present study elucidated the nature of these follicular lesions. Thyroid glands of 10 rats each from the control, high (100 ng/kg/day)-dose, and stop-study (100 ng/kg/day, 30 weeks; vehicle to study termination) groups in the 2-year study were evaluated microscopically. Twenty randomly selected follicles were measured morphometrically in each animal. TCDD treatment significantly decreased the mean ratio of luminal/epithelial areas and increased the mean sectional epithelial height of the high-dose group compared to controls. Thyroid sections were immunostained with antibody against minichromosome maintenance (MCM) proteins, a novel cell-cycle biomarker. The MCM labeling index of the high-dose group was significantly higher than that of the control; however, the TUNEL labeling index was also higher in the high-dose group than the control. All data from the stop group were comparable to those from controls. These results indicate that the follicular cell response was hypertrophic and reversible. This information should contribute to diagnosis of nonneoplastic thyroid follicular lesions in rats.  相似文献   
25.
26.
S Kayashima  S Tsuru  N Hata    M Rokutanda 《Immunology》1993,80(3):471-476
Anti-listerial activity in SCID mice as well as in control C.B-17 mice was augmented by granulocyte colony-stimulating factor (G-CSF). After 1 x 10(3) colony-forming units of Listeria monocytogenes (strain EGD) were intravenously inoculated, mice were intraperitoneally injected with G-CSF at a daily dose of 500 micrograms/kg for 5 days. The numbers of viable bacteria in the liver were significantly lower in G-CSF-treated SCID and C.B-17 mice than in non-treated mice. The surface marker analyses on gamma delta T-cell receptor (TcR), Mac-1 and F4/80, and dichlorofluorescein oxidative activity, showed a possible contribution of activated neutrophils, but not gamma/delta T cells nor activated macrophages, to the augmentation of anti-listerial activity in SCID mice. This study is one of the first reports on the anti-microbial effect of G-CSF in therapeutic use.  相似文献   
27.
The 6-amino-6-deoxy-N-acetylmuramyldipeptides and their 6-acylamino derivatives were shown to be active as adjuvants on the induction of delayed-type hypersensitivity to azobenzenearsonate-N-acetyl-l-tyrosine in guinea pigs. However, 6-acylamino-6-deoxy-N-(acyl)muramyldipeptides were inactive as adjuvants.  相似文献   
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29.
Diverse functions of the p75 neurotrophin receptor   总被引:5,自引:0,他引:5  
The pan-neurotrophin receptor p75NTR belongs to a large family of receptors, which includes tumor necrosis factor receptors, Fas and approximately 25 other members. The p75NTR is the first receptor to be cloned molecularly. Recent years have seen the emergence of a consensus regarding the signaling pathways activated by p75NTR and its potential biological function, although receptor characterization had not been targeted for some years. We now know that p75NTR has surprisingly diverse effects, ranging from cell death to regulation of axon elongation. This diversity can be explained by the complex formation of p75NTR with other receptors and multiple signaling molecules that interact with the intracellular domain of p75NTR.  相似文献   
30.
An autopsy case of massive renal hemorrhage in a 49-year-old male who had undergone maintenance hemodialysis for 8 years, is reported. No bleeding tendency had been noticed, and blood pressure had been reduced to within the normal range. Histological investigation with semiserial sections revealed that hemorrhage had occurred in four arteries, corresponding to the interlobar, arcuate, and interlobular levels, which existed in the same ruptured cyst wall. Acute dissection had occurred in two of the four arteries, leading to rupture of the cyst; this led to destruction of the remaining arteries. Both kidneys, which were markedly shrunken and had numerous cysts in the cortex and medulla, fell into the category of acquired cystic renal disease of long-term hemodialysis. It was suspected that renal vascular change during hemodialysis, mechanical factors compressing the protruding artery in the cyst with scanty renal interstitium, and relatively radical hemodynamic changes during dialysis had contributed to the hemorrhage.  相似文献   
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