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The authors have previously reported that homologous immunoglobulin (Ig)G reduces the occurrence of dextran sulfate sodium (DSS)-induced colitis, mainly by suppressing recruitment of immunocompetent cells into colitis lesions. However, the mechanisms of cell recruitment and of its suppression by IgG remain unclear. In addressing these questions, this study focused on the activation of T cells in the presence of macrophages. The authors found that [3H]-thymidine uptake of T cells from DSS-induced colitis mice, but not from normal mice, was significantly enhanced when cultured with DSS-pulsed macrophages. From the profile of cytokine production, it was suggested that T helper 1 (Th1)-type cells become predominant during stimulation. Addition of homologous IgG significantly suppressed T cell proliferation in a dose-dependent manner, while no suppressive effect was observed with heterologous IgG. Mouse IgG F(ab')2, but not Fc, fragments partially mimicked the suppressive effect of whole IgG. These findings provide evidence that Th1-type cells may play an important role in the development of DSS-induced colitis and that homologous IgG exerts its protective action at least in part through the F(ab')2 portion.  相似文献   
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Neutrophilic dermatoses (ND), with or without accompanying myelodysplastic syndrome (MDS), were examined in terms of nuclear abnormality like pelgeroid anomaly of infiltrating cells into skin lesions. Six ND accompanying MDS showed 1.0 to 13.5% of such anomalous cells among infiltrating cells. In contrast, ND without accompanying myeloproliferative disorders rarely had such anomalous cells. Our findings suggest that pelgeroid-like anomalous cells infiltrating into ND are probably a good marker of underlying MDS.  相似文献   
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In a patient with sustained ventricular tachycardia, we obtained two different paced QRS morphologies from a single pacing site. In one QRS morphology the stimulus to the QRS complex was long, 150 msec, and in the other it was 100 msec. At the paced cycle length of 600 msec and the stimulus output of 4 V, one QRS morphology with the stimulus to the onset of QRS activation (St-QRS) interval of 150 msec was observed. At the paced cycle length of 400 msec, the other QRS morphology with a St-QRS interval of 100 msec was observed alternatively with the former. At the paced cycle length of 353 msec or 316 msec, the latter with a shorter St-QRS interval was exclusively observed. When the stimulus output was increased from 4 to 10 V, keeping with the paced cycle length at 400 msec, the St-QRS interval was shortened from 100 to 80 msec. For the two QRS morphologies with two St-QRS intervals, two slowly conducting pathways would be responsible. The site of the block in the faster pathway must be located at the proximity of the pacing site and the conduction at a shorter paced cycle length would be explained by "supernormal conduction."  相似文献   
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Pharmacokinetk Analysis of Increased Toxicity of 2-sec-ButylphenylMethylcarbamate (BPMC) by Fenitrothion Pretreatment in Mice.TSUDA, S., MIYAOKA, T., IWASAKI, M., AND SHIRASU, Y. (1984).Fundam. Appl. Toxicol. 4, 724–730. The potentiating effectof O,O-dimethyl O-(3-methyl-4-nitrophenyl) phosphorothioate(fenitrothion) on the toxicity of 2-sec-butylphenyl methylcarbamate(BPMC) in male mice was analyzed pharmacokinetically. The animalspretreated by dietary administration of 1000 ppm fenitrothionfor 1 week (4.4% of the po LD50 daily) did not show toxic symptomsexcept for a slight decrease in body weight In the fenitrothion-pretreatedmice, toxicity of fenitrothion was not changed but a fivefoldpotentiation was observed in po and ip acute lethality and athreefold potentiation of iv lethality of BPMC. Toxic signsafter BPMC administration were similar regardless of fenitrothionpretreatment or of route of administration. Fenitrothion pretreatmentfollowed by BPMC administration (20 mg/kg po or 8 mg/kg iv,approximate LD5 in the pretreated mice) significantly increasedthe plasma BPMC concentration and the total area under the plasmaconcentration versus time curve (AUG0-. The pretreatment increasedthe oral AUC0-, more greatly than the iv AUC0-, (for po, 6.3-fold;for iv, 2.0-fold). The oral systemic availability of BPMC (fractionreaching systemic circulation) was increased by fenitrothiontreatment to 3.3-fold. These results suggest that a major causeof the potentiation may be the increase in amount of BPMC inthe systemic circulation.  相似文献   
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We evaluated the effects of the seed saponins of Thea sinensisL. on alcohol absorption and metabolism in rats and mice. Anethanolic extract from the seeds of T. sinensis was orally administeredto the rats 1 hr before or 0.5 hr after administration of ethanol(2 g/kg), and the blood ethanol assayed 0.5, 1, 2, 3, and 4hr after ethanol administration. The ethanol level decreasedafter both pie- and post- administration of the extract. Theextract was further purified to obtain a saponin fraction whichwas orally administered to mice 1 hr before ethanol administration.Blood, liver, and stomach were obtained 0, 1, 3, and 6 hr afterethanol administration, and the ethanol, acetaldehyde, acetate,and acetone concentrations in each specimen were measured byhead space gas chromatography. The saponin fraction decreasedthe ethanol levels in the blood and liver but increased thatin the stomach five-fold over the control level, suggestinginhibition of alcohol absorption. The ethanol disappearancetime from the blood was shortened, suggesting the promotionof alcohol disappearance. The acetate and acetone levels wereunaffected. However, the acetaldehyde level decreased in theblood, liver, and stomach. The decreases in the ethanol andacetaldhyde levels in the liver suggested the protective effectsof the seed saponins on the liver. The saponins did not directlyinhibit hepalic alcohol dehydrogenase activity. The seed saponinsof T. sinensis seem to suppress alcohol absorption by slowinggastric emptying and by inhibiting absorption across the cellmembranes of the digestive tract.  相似文献   
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Combined Repeat Dose and Reproductive/Developmental ToxicityScreening Test (OECD): Familiarization Using Cyclophosphamide.TANAKA, S., KAWASHIMA, K., NAITO, K., USAMI, M., NAKADATE, M.,IMAIDA, K., TAKAHASHI, M., HAYASHI, Y., KUROKAWA, Y., AND TOBE,M. (1992A, Y., AND TOBE, M. (1992). Fundam. Appl. Toxicol. 18,89–95. A familiarization study was conducted on the "Combined RepeatDose and Reproductive/Developmental Toxicity Screening Test(ReproTox)" proposed by the OECD. Cyclophosphamide (CP) at dosesof 6.7, 4.5, 3, 2, and 0 mg/kg body wt was given daily by gavageto groups of 12 male and 12 female Sprague-Dawley rats. As aresult, anemia and leukopenia were evident in treated males.The absolute and relative thymus and spleen weights were decreasedin treated rats. Histopathologically, atrophy of the thymus,spleen, and bone marrow was observed. With respect to the reproductive/developmentaltoxicity, dose-dependent increases in postimplantation lossof fetuses and postnatal death were found in dams given CP.The body weight of pups treated with CP was significantly loweredin a dose-related manner. Thus the results demonstrated mostof the known toxicological properties of CP, except the adverseeffects on spermatogenesis and fertility. Therefore ReproToxcan be considered as a useful screening test for assessing repeatdose and reproductive/developmental toxicity of existing chemicalsof high production volume.  相似文献   
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BACKGROUND: In Asian countries, glycerol solution that contains fructose (5%) is often used for management of brain edema. However, glycerol and fructose may cause severe hypoglycemia and metabolic acidosis in patients with fructose-1,6-bisphosphatase (FBPase) deficiency, even under stable conditions. The aim of the present study was to determine whether glycerol solution was used for brain edema during acute metabolic decompensation of hypoglycemia and metabolic acidosis in patients with unrecognized FBPase deficiency in Japan and to examine a long-term prognosis of the patients who had this kind of severe metabolic decompensation with or without glycerol therapy. METHODS: A retrospective study of 20 children with FBPase deficiency was conducted, based on their medical records. RESULTS: Six of the 20 children were given glycerol solution for the presence or possibility of brain edema during acute metabolic decompensation of hypoglycemia and metabolic acidosis; two of the six patients administered with glycerol were given dialysis. In four patients treated with glycerol alone without dialysis, two had no brain edema before glycerol administration but it developed later after the administration. These four patients treated with glycerol alone died or developed severe neurological complications. Fourteen patients who were not treated with glycerol solution had no brain edema and showed good prognosis. CONCLUSIONS: Glycerol solution, which contains fructose in Asian countries including Japan, should not be used as an osmotic agent for treatment of brain edema in patients who have hypoglycemia and retention-type metabolic acidosis, until FBPase deficiency is ruled out by measuring blood concentration of lactate.  相似文献   
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BACKGROUND: We report our experience with Gas-less laparoscopy-assisted surgery (Gas-less LAS), hand-assisted laparoscopic surgery (HALS) and pure laparoscopic surgery (LS) for renal carcinoma and compare the characteristics and usefulness of these methods. METHODS: Seventeen, 14 and 16 patients were subjected to Gas-less LAS, HALS and LS, respectively. The study started with Gas-less LAS and then gradually shifted to HALS and LS. We evaluated the operative and postoperative parameters for each group. The learning curve effect was evaluated based on data from the first 10 cases of each group, which were operated on by the same surgeon and operation team. RESULTS: The learning curve of operation times in the LS group demonstrated that the operation time for this procedure is acceptable even in early-stage cases. Differences in mean operative time between the three surgical groups, excluding the conversion cases, were not statistically significant; however, there was a significant difference in blood loss volume between the groups (P 相似文献   
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