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11.
The occurrence of late asthmatic response (LAR) is effectively prevented by corticosteroids, but not all by beta-adrenergic drugs. LAR is considered to be of great clinical and therapeutic importance and to be involved in the progression of bronchial asthma into a severe or even an intractable form. However the exact mechanism of the occurrence of LAR remains obscure in many respects. LAR is believed to be due to type I allergy. In guinea pigs, a positive bronchial inhalation challenge following passive sensitization with allogeneic antibody does not induce LAR or eosinophilic infiltration of lung tissue. This experimental fact led us to surmise that LAR would seem likely to be elicited in passively sensitized animals if pronounced eosinophilic infiltration can be induced concurrently and to conduct an experiment with conjoined inhalation of platelet activating factor (PAF). PAF, which has a chemotactic activity for eosinophils, was administered to passively sensitized animals in attempt to examine a role of eosinophils in LAR. A goodly number of animals developed LAR on additional PAF inhalation. These animals, when compared with those without LAR, showed a significantly larger proportion of eosinophils in BALF (p less than 0.05) with an upward tendency for the proportion of neutrophils. Histologically, there was noted a striking association between LAR and eosinophilic infiltration of the bronchial submucosa. These results suggest that anti-IgE antibody is deeply involved in the elicitation of LAR, stressing the importance of eosinophilic infiltration. 相似文献
12.
Evidence for the involvement of a plasma kallikrein-kinin system in the immediate hypotension produced by endotoxin in anaesthetized rats. 总被引:4,自引:4,他引:0
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M. Katori M. Majima R. Odoi-Adome N. Sunahara Y. Uchida 《British journal of pharmacology》1989,98(4):1383-1391
1. In vitro incubation of normal rat plasma with endotoxin from E. coli (3-10 mg ml-1) in the incubation mixture) caused a dose-dependent increase in levels of free kinin and plasma kallikrein in the presence of o-phenanthroline, together with a mirror-image, dose-dependent decrease in the residual levels of the precursors, plasma prekallikrein and high-molecular-weight kininogen. Low-molecular-weight kininogen levels were not modified. 2. Intravenous injection of endotoxin (3-30 mg kg-1) into the femoral vein of anaesthetized rats resulted in dose-dependent hypotension. In blood collected up to 15 min after injection, the levels of prekallikrein and high-molecular-weight kininogen in plasma were decreased while levels of the active forms, plasma kallikrein and free kinin, showed a transient increase in the blood 1 min after administration of endotoxin. 3. A degradation product of bradykinin, des-Phe8-Arg9-bradykinin, as measured by a newly developed enzyme immunoassay, was detectable up to 5 min after administration of endotoxin. 4. Intravenous infusion of soybean trypsin inhibitor inhibited both the formation of bradykinin and des-Phe8-Arg9-bradykinin and the initial hypotension. 5. It can be concluded from our results that plasma prekallikrein is activated in the blood immediately after administration of endotoxin to rats and that bradykinin is a major cause of the immediate hypotension. 相似文献
13.
Tissue specimens from patients with the scirrhous type of gastric carcinoma were stained using the peroxidase-antiperoxidase (PAP) method. Nine out of thirty-seven specimens (24 per cent) showed positive estrogen staining, and here tissues from male or older patients were usually stained. Cumulative survival rate in patients whose tissue showed a positive estrogen staining was higher than that in case of a negative estrogen staining. Four out of thirty-one specimens (13 per cent) stained positively for progesterone, all four patients being male. These results suggest that estrogen and progesterone may relate to the growth of the scirrhous type of gastric cancer. 相似文献
14.
Information concerning surgical treatment of adult patients with chronic sinusitis was obtained through questionnaires from 434 hospitals in Japan. The hospitals were authorized for an in-service otorhinolaryngological training institute by the Oto-Rhino-Laryngological Society of Japan. The questionnaires were sent to the hospitals in December, 1989, and answers were obtained from 370 hospitals within 2 months, an 85.3% response rate. The following results were obtained. In 96.2% of the hospitals, permaxillary sinus surgery was performed on patients whose maxillary and ethmoid lesions were severe. With moderate lesions of both the maxillary and ethmoid sinuses, permaxillary sinus surgery and endonasal sinus surgery were performed in 76.0% and 24.9%, respectively. Application of an endoscope for sinus surgery was reported by 89 hospitals. In January, 1990, a further survey was sent to the 89 hospitals where endoscopic sinus surgery was performed. Questionnaire responses were obtained from 75 hospitals. Rigid endoscope was used most frequently and operative microscope was also used. Endoscopy was applied to all of the sinus surgery procedures in 21.6%, and to a portion of the procedures in 74.3% of the hospitals. About 50% of the hospitals performed endoscopic surgery in fewer than 30% of sinus surgery cases. When questioned as whether endoscopic surgery had been successful, 42.6% said yes, 10.7% said no, and 42.6% were unsure. 相似文献
15.
Yoshinori Hirashima Kazuaki Kitajima Saori Sugi Koichi Kagawa Kazunari Murakami Toshio Fujioka Toshihide Kumamoto 《Nihon Shokakibyo Gakkai zasshi》2007,104(5):660-665
A 75-year-old man was admitted to our hospital with the chief complaint of a choking feeling around the esophagus. Laboratory examinations revealed eosinophilia, and high levels of serum immunoglobulin (Ig) E. A computed tomography scan (CT) showed wall thickening of the esophagus and terminal ileum, and ascites around the liver. An endoscopic examination revealed mild mucosal edema in the esophagus, stomach, and small intestine. Biopsy specimens showed diffuse eosinophilic infiltration in the mucosa. We therefore diagnosed eosinophilic gastroenteritis. Oral prednisolone relieved clinical conditions and the CT image improved. This case was considered valuable, because there have been few reports of eosinophilic esophagitis in Japan. 相似文献
16.
碱性成纤维细胞生长因子受体基因在牛眼晶体上皮细胞内的表达 总被引:1,自引:0,他引:1
目的探讨碱性成纤维细胞生长因子(basicfibroblastgrowthfactor,bFGF)对晶体上皮细胞促增殖作用的机理。方法从培养的第二代牛眼晶体上皮细胞提取RNA,经逆转录反应合成cDNA。借助从人体胎盘纤维细胞bFGF受体序列合成的寡核苷酸引物,聚合酶链反应体外扩增cDNA。扩增的cDNA片段克隆后,Sanger双脱氧链终止法测定其序列。结果探测出牛眼晶体上皮细胞bFGF受体的mRNA,测序后发现其氨基酸序列片段中仅3个氨基酸与人体不同。结论晶体上皮细胞存在bFGF受体,当bFGF与其受体结合后,对促进晶体上皮细胞的增殖以及白内障术后后囊混浊具有重要作用。 相似文献
17.
18.
Nakanishi M Yabe S Tanaka N Ito Y Nakamura KT Kitade Y 《Molecular and biochemical parasitology》2005,143(2):146-151
S-adenosylhomocysteine hydrolase is a prospective target for developing new anti-malarial drugs. Inhibition of the hydrolase results in an anti-cellular effect due to the suppression of adenosylmethionine-dependent transmethylations. Based on the crystal structure of Plasmodium falciparum S-adenosylhomocysteine hydrolase which we have determined recently, we performed mutational analyses on P. falciparum and human enzymes. Cys59 and Ala84 of the parasite enzyme, and the equivalent residues on the human enzyme, Thr60 and Gln85, were examined. Mutations of Cys59 and Thr60 caused dramatic impact on inhibition by 2-fluoronoraristeromycin without significant effect both on its kinetic parameters and on inhibition constant against noraristeromycin. In addition, the impact was independent from the electronegativity of the side chain of the substituting residue. These results showed that steric hindrance between a functional group at the 2-position of an adenine nucleoside inhibitor and Thr60 of the human enzyme, not an electrostatic effect, contributed to inhibitor selectivity. 相似文献
19.
Takahashi S Ogasawara H Hiwatashi K Hata K Hori K Koizumi Y Sugiyama T 《Biomedical research (Tokyo, Japan)》2005,26(3):117-121
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
20.
Specific Inhibitory Action of Anisodamine against a Staphylococcal Superantigenic Toxin, Toxic Shock Syndrome Toxin 1 (TSST-1), Leading to Down-Regulation of Cytokine Production and Blocking of TSST-1 Toxicity in Mice
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