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81.
82.
Interferon-gamma inhibits transforming growth factor-beta production in human airway epithelial cells by targeting Smads 总被引:8,自引:0,他引:8
83.
Adenosine potentiates neurally- and histamine-induced contraction of canine airway smooth muscle 总被引:1,自引:0,他引:1
N Sakai J Tamaoki K Kobayashi M Katayama T Takizawa 《International archives of allergy and applied immunology》1989,90(3):280-284
We studied the effect of adenosine on airway reactivity of isolated canine bronchial smooth muscle under isometric conditions in vitro. Administration of adenosine and its analogs increased the contractile responses of bronchial segments to electrical field stimulation in a dose-dependent fashion, where the rank order potency was N-ethylcarboxamideadenosine greater than adenosine greater than N-cyclohexyladenosine, but had no effect on those to exogenous acetylcholine. This potentiation was more pronounced at relatively low than at high stimulus frequencies, the maximal increase from the baseline responses being 56.3 +/- 9.6% at 1 Hz (mean +/- SE, p less than 0.01). Adenosine also increased the histamine-induced contraction causing a leftward shift of the histamine dose-response curves, an effect that was abolished in the presence of atropine. These results suggest that adenosine potentiates airway responsiveness to vagal stimulation and to histamine through the activation of prejunctional A2 receptor, probably involving the accelerated release of acetylcholine from the cholinergic nerve terminals. 相似文献
84.
This study deals with 11 cases of thyroid medullary carcinoma of which 7 were familial cases including 3 cases of Sipple's syndrome and 4 cases of sporadic cases. There were also 2 cases of Cushing's syndrome. In addition to the previously described English literatures about human medullary carcinoma of the thyroid, the rod-shaped body with cristae and an abundant glycogen particles in the cytoplasm, nuclear inclusion bodies of cytoplasmic invagination and microvilli at the surface membrane of gland formation were found in our cases. The mean and mode diameters of secretory granules of all familial cases with only calcitonin secretion were larger than those of the sporadic cases with ectopic AGTH and beta-MSH in addition to calcitonin secretion. Ultrastructural study on non-cancerous follicles of grossly normal thyroid of two cases of early familial medullary carcinoma disclosed apparently increased C-cells which were not intrathyroidal metastases. It is supposed that the increased C-cells in the thyroid of the familial cases are multicentric C-cell hyperplasia. ACTA PATH. JAP. 27: 605˜622, 1977. 相似文献
85.
I Katayama K Nishioka K Nishida T Doi 《International archives of allergy and applied immunology》1984,73(4):289-295
It was recently demonstrated that there was a specific activity to induce basophil-rich skin reaction in the sera of contact-sensitized guinea pigs (CBH factor, CBH-F). In the in vitro chemotactic assay system, CBH-F was shown to have weak basophil chemotactic activity but enhanced its activity in the presence of corresponding antigen(s). Furthermore, basophil chemotaxis in reaction to the antigen(s) was observed when the cells were preincubated with CBH-F. It worked mainly for Percoll-separated bone marrow basophils but not for oil-induced peritoneal macrophages. Immunological analysis revealed that CBH-F was a protein with a small molecular weight (MW 4-6 X 10(4] with an antigen binding site and isoelectric point of between 4.5 and 5.0. It did not show any characteristics of IgG1 or IgG2 on immunoadsorbent column and immunoelectrophoresis. Enzyme treatment with insoluble trypsin eliminated the chemotactic activity but this was not the case with neuraminidase treatment. 相似文献
86.
87.
Isao Katayama Masaki Shimizu Myota Miura Masanobu Maruyama Masayuki Kobayashi Yuuichi Iino Masaru Izuo Susumu Wakatsuki 《Virchows Archiv : an international journal of pathology》1984,402(4):353-359
Summary In a study of 277 patients with breast carcinomas, the PAP immunoperoxidase method for demonstrating endogenous estrogen was correlated with the sucrose density gradient (SDG) assay and with histologic and clinical features. The results from the PAP method and SDG assay agreed in 59 of 84 patients (82.1%) on whom both methods were performed. Histologically, the PAP method was positive in 7 of 7 patients with non-invasive carcinomas, in 164 of 233 patients (70.4%) with common invasive ductal carcinoma, and in 21 of 22 of those with special histological types of invasive carcinomas not including Paget's disease, medullary or apocrine carcinoma, where only 5 of 14 were positive. Clinically, 15 of 18 patients with positive endogenous estrogen showed a response to endocrine therapy as opposed to 1 of 9 patients with a negative endogenous estrogen. The mean survival was 31.2 and 15.6 months, respectively for patients with positive and negative endogenous estrogen. Remission for longer than 2 years was seen more often in patients with positive endogenous estrogen. These results suggest a clinical utility of the present PAP method which, therefore, deserves a further trial as an alternative to histochemical methods aiming at the estrogen receptors.This work was supported by Grants-in Aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan (No. 56480119).This paper was presented at the 72nd Annual Meeding of International Academy of Pathology (United States-Canadian Division), Atlanta, Georgia, March 1, 1983. 相似文献
88.
The nature of the suppressive activity in the peritoneal exudate cells (PEC) of guinea-pigs immunized with dinitrophenyl bovine gamma globulin (DNP50-BGG) was investigated. A method was developed to isolate from the peritoneal exudate large numbers of macrophages. Using density gradient centrifugation on Percoll it was possible to obtain a population of cells which contained over 90% macrophages. This macrophage preparation was found to respond to lymphokine but to be incapable of passively transferring delayed hypersensitivity reactions. When these immune macrophages were transferred into antigen immunized animals, which had been pretreated with cyclophosphamide (CY), the skin reactions were suppressed to the same extent as when the total PEC was transferred. PEC from guinea-pigs immunized with ovalbumin in Freund's incomplete adjuvant did not suppress the skin reactions in CY-pretreated DNP50BGG immunized animals. However, in contrast, macrophages from these animals did suppress the skin reactions in the recipient guinea-pigs indicating that the macrophage suppression was not antigen specific. 相似文献
89.
Yusuke Komiya Makoto Sugiyama Masaru Ochiai Nanako Osawa Yuto Adachi Shugo Iseki Keizo Arihara 《Nutrients》2021,13(4)
Olive oil is a functional food shown to have a variety of bioactive effects. Therefore, we expect it to be a novel functional food with an exercise-mimetic effect on skeletal muscles. This study aimed to investigate the effect of olive oil on the endurance capacity and muscle metabolism in mice. Mice fed a 7% (w/w) olive oil diet for eight weeks showed improved treadmill running endurance and increased intramuscular triacylglycerol (IMTG) accumulation in the gastrocnemius muscle compared to soybean oil diet-fed controls. The increase in running endurance with olive oil intake was independent of the muscle fiber type. To elucidate underlying the mechanism of elevated IMTG levels, we examined the expression levels of the genes related to lipid metabolism. We found that the expression of diacylglycerol O-acyltransferase1 (DGAT1) was significantly upregulated in the muscle of olive oil diet-fed mice. In addition, the olive oil diet-fed mice showed no metabolic impairment or differences in growth profiles compared to the controls. These results suggest that dietary olive oil intake affects muscle metabolism and muscle endurance by increasing energy accumulation. 相似文献
90.