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51.
P15E is a specific sequence among the envelope gene (env)-encoded transmembrane proteins of exogenous and endogenous retroviruses. A synthetic peptide (CKS-17) that shows homology to this p15E region in several species of retrovirus is known to induce immune abnormalities. In this study, we examined the effect of a synthetic peptide derived from a region of human endogenous retrovirus (HERV) clone 4-1 ( 4-1) similar to sequences of CKS-17 on the induction of systemic lupus erythematosus (SLE)-related immune abnormalities. Our results indicated that this peptide could induce T-cell activation and anergy in normal peripheral blood mononuclear cells, and the peptide could also promote the production of interleukins IL-6 and IL-16. These phenomena are representative immune abnormalities observed in SLE patients. Thus, our findings support the possibility that HERV acts as a pathogen in human SLE.  相似文献   
52.
Physical exercise has beneficial effects not only on cardiovascular system and fat metabolism, may also directly effect the cognitive process. We studied the effect of physical exercise on cognitive processes by measuring the P300 event related-potential (ERP) after jogging. Seven well-trained joggers were enrolled in this study and the P300 potentials using auditory oddball paradigm. ERPs were measured before and after 30 minutes of jogging. The amplitude of the P300 significantly increased after jogging compared to values recorded before jogging. These findings suggest that jogging has the effect of facilitating cognitive processes involved in generation of the P300.  相似文献   
53.
54.
Passive cutaneous anaphylaxis (PCA) mediated in rats by IgE-like antibodies against egg albumin or the benzylpenicilloyl determinant was inhibited in a dose-dependent manner by intravenous treatment with Y-12,141; the ED50 was 0.09--0.2 mg/kg. The inhibitory effect of Y-12,141 ON PCA was about 5 times as potent as that of disodium cromoglycate (DSCG). Oral treatment with Y-12,141 resulted in the inhibition of PCA, showing an ED50 of 2.5 mg/kg. This action of Y-12,141 on PCA was considered to be due to the inhibition of the release of allergic mediatros from mast cells in a manner similar to DSCG. The results suggest that Y-12,141 may have an anti-allergic activity.  相似文献   
55.
Prolactin-releasing peptide (PrRP) was found to be a novel hypothalamic peptide that stimulates prolactin release in vitro and in vivo. In the normal adult rat brain, PrRP neurons are known to be located in only three areas, i.e. the dorsomedial hypothalamic nucleus, ventrolateral reticular formation; and nucleus of the tractus solitarius in the medulla oblongata. These PrRP neurons project neurites into various brain areas, including regions such as the paraventricular nucleus, supraoptic nucleus, and bed nucleus of the stria terminalis. Both PrRP nerve fibers and a high level of PrRP receptor, UHR-1, mRNA are observed in the area postrema (AP),but no PrRP neurons are detected in the AP of normal rats. In this study, we clearly demonstrated that PrRP-producing cells newly appeared in the AP of adrenalectomized rats by in situ hybridization and immunocytochemistry. Our results suggest that PrRP may have some important roles in the AP of adrenalectomized rats. This is the first report demonstrating the appearance of PrRP-positive cells in the AP.  相似文献   
56.
Granulocyte-macrophage colony-stimulating factor (GM-CSF) produced by splenic lymphocytes obtained from Schistosoma japonicum-infected mice was partially purified by a combination of DEAE anion-exchange chromatography, concanavalin A-Sepharose affinity chromatography, and high-pressure liquid chromatography. When this partially purified GM-CSF was added to the culture of isolated intact granulomas, eosinophil chemotactic factor (ECF) lymphokine production by granulomas was significantly enhanced. The partially purified GM-CSF also enhanced ECF lymphokine production by granuloma T cells cocultured with syngeneic macrophages and specific antigen. The partially purified GM-CSF itself had neither ECF activity nor a synergistic effect with ECF lymphokine. When normal splenic macrophages were preincubated with the partially purified GM-CSF, they potentiated the ECF production by granuloma T cells under the presence of specific antigen. Augmentation of ECF lymphokine production by partially purified GM-CSF was further confirmed by using T-cell clones that were established from granuloma T cells. These results suggest that T-cell-derived GM-CSF primarily activate macrophages so that these activated macrophages can cooperate more effectively with T lymphocytes to produce ECF. Such potentiation of macrophage-T-cell interaction by GM-CSF may be important in the mechanisms of granuloma formation during an acute stage of schistosomiasis.  相似文献   
57.
A phase-sensitive detection method in combination with whole-cell voltage-clamp was applied to exocrine pancreatic acinar cells from rat. The results have shown that cell-aialysis with a solution containing 5×10–7 M Ca2+ induces stp-wise changes in cell capacitance. The size distribution of increasing and decreasing capacitance steps is compatible with the idea that these capacitance steps are the results of individual granular fusion and retrieval events. This method may enable experiments studying the exo-and endo-cytotic mechanisms in morphologically polarized secretory cells.  相似文献   
58.
We undertook an investigation in which flow cytometry was used to characterize immune cell populations in the decidua of first-trimester normal pregnancies, spontaneous abortions, and ectopic pregnancies in comparison to the nonpregnant endometrium to demonstrate how the proportions of immunocompetent cell populations at the fetomaternal interface are influenced by the presence and state of a fetoplacental allograft. No significant differences were found in the decidua of the different types of first-trimester pregnancy in the proportions of the CD45+, CD14+, CD3+, CD4+, CD8+, CD19+, CD3-/CD16+ and/or CD56+, CD3+/CD16+ and/or CD56+, CD4+/Leu-8+, CD4+/Leu-8-, CD8+/CD11b+, CD8+/CD11b-, and CD3+/HLA-DR- decidual leukocyte subsets. However, the percentage of decidual CD3+/HLA-DR+ cells, which are characteristic of activated T cells, was significantly higher in spontaneous abortions than in normal pregnancies (p less than 0.05). This suggests that the accumulation of decidual leukocytes may be regulated mainly by hormones and/or cytokines rather than by the presence and state of an intrauterine conceptus and that on/off-switching of activation of decidual T cells may be associated with successful maintenance of the implanted embryo.  相似文献   
59.
Dendritic cells within the dermis in the later stages of delayed-type contact hypersensitivity were examined ultrastructurally and immunohistochemically. The immunohistochemical observations were done using monoclonal antibody M1-8, which reacts specifically with murine Langerhans cells and interdigitating cells. Seventeen hours after challenge, infiltrating cells in the dermis included dendritic cells, possibly so-called indeterminate cells, monocytoid cells and Langerhans cells. Immunohistochemically, the indeterminate cells and some monocytoid cells were M1-8-positive. These findings suggest that indeterminate cells are intimately related to Langerhans cells, and that they belong to the mononuclear phagocyte system. M1-8 is a very useful marker for studies on the kinetics of Langerhans cells or indeterminate cells.  相似文献   
60.
The effectiveness of the clinical pathway for laparoscopic cholecystectomy was evaluated, and the efficiency of medical care was analyzed. The duration of hospitalization and the number of National Health Insurance (NHI) points for medical service fees were compared between 86 patients treated after introduction of the clinical pathway (pathway group) and 56 patients treated before introduction of the clinical pathway (pre-pathway group). In the pathway group, variance from the pathway occurred in 24 patients (27.9%) due to postponement of discharge in 7 patients, to earlier discharge in 5 patients, and to insertion of a bile duct catheter in 5 patients. Total and postoperative hospitalization times were significantly shorter in the pathway group than in the pre-pathway group (8.0 +/- 1.6 vs 13.7 +/- 9.0 days, p<0.0001, 5.4 +/- 1.1 vs 6.5 +/- 2.2 days, p<0.0001, respectively). In the pathway group, the total number of NHI points was lower and the number of points per day was higher. By simulation, the total number of NHI points for the 5-day pathway (discharge on postoperative day 3 or earlier) was significantly lower than that for the current 7-day pathway. Moreover, the weekly profit per bed with the 3-day pathway (discharge on postoperative day 1) was more than twice that with the current pathway. The results suggest that the clinical pathway for laparoscopic cholecystectomy is beneficial for patients and useful for the introduction of diagnosis procedure combination in our hospital.  相似文献   
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