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41.
42.
Effect of serotonin on murine macrophages: suppression of Ia expression by serotonin and its reversal by 5-HT2 serotonergic receptor antagonists 总被引:2,自引:0,他引:2
Serotonin (5-HT), a mediator released from platelets at sites of inflammation, suppressed IFN-gamma-induced Ia expression in mouse bone marrow macrophages maintained in vitro. (Mean percent suppression = 63.9% +/- 9.2, n = 40.) This suppression was not toxic or endotoxin-related, was concentration-dependent, and occurred at the physiologic concentrations of 5-HT present at inflammatory sites. The concentration of 5-HT producing the half-maximal effect was 2.5 to 5.5 X 10(-8) M. Related compounds, dopamine, histamine, and tryptamine, were much less potent in suppressing IFN-gamma-induced Ia, with maximally suppressing concentrations more than 100-fold higher than the maximally suppressing 5-HT concentration. L-5-hydroxytryptophan (5-HTP), the most potent analog tested, was 10-fold less potent than 5-HT in suppressing Ia expression. The concentration of 5-HTP producing the half-maximal effect = 4 X 10(-7) M. 5-HT suppression of IFN-gamma-induced Ia expression was antagonized by the 5-HT2 type receptor antagonists spiperone, ketanserin, and LY53857. Concentrations of these agents resulting in 50% inhibition of the serotonin effect were 1.5 X 10(-8) M, 7.5 X 10(-8) M, and 4.5 X 10(-12) M, respectively. 5-HT was most effective in suppressing IFN-gamma-induced Ia when added early in culture simultaneously with IFN-gamma. These data provide functional evidence that 5-HT suppression of IFN-gamma-induced Ia expression is mediated through a 5-HT receptor with some characteristics of the 5-HT2 type. 5-HT may play a physiologic role at sites of inflammation as a modulator of the effects of IFN-gamma on macrophage function. 相似文献
43.
Douglas M. Carlson William L. Pflieger Linden Trial Pamela S. Haverland 《Environmental Biology of Fishes》1985,14(1):51-59
Synopsis
Scaphirhynchus albus and S. platorynchus were studied in Missouri during 1978–1979 to assess their distribution and abundance, to obtain information on their life
histories, and to identify existing or potential threats to their survival. S. platorynchus was collected in substantial numbers (4355 specimens) at all 12 sampling stations in the Missouri and Mississippi rivers,
while only 11 S. albus were captured from 6 stations. Twelve specimens identified in the field as hybrids between the two species were captured
from 4 stations. Morphometric and meristic comparisons of presumed hybrids with the parent species, using cluster and principal
components analyses, demonstrated intermediacy of most specimens identified in the field as hybrids. Aquatic insects comprised
most of the diet of S. platorynchus and S. albus, but S. albus and the hybrids had consumed considerable quantities of fish. S. albus grew more rapidly than S. platorynchus, while the growth of hybrids was intermediate. Hybridization appears to be a recent phenomenon, resulting from man-caused
changes in the big-river environment. Hybridization may be a threat to survival of S. albus in the study streams. 相似文献
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抗胃癌细胞系单克隆抗体PD4的初步研究 总被引:1,自引:0,他引:1
以胃癌细胞系MGC803免疫Balb/c小鼠,取其脾细胞与小鼠骨髓瘤细胞NS-1融合。经选择培养、筛选及克隆化,获得恒定地分泌抗胃癌细胞系单克隆抗体(MoAb)的杂交瘤细胞系PD4。MoAb PD4与3/4胃癌细胞系有强结合反应,与4/4肺癌细胞系有弱结合反应,但与淋巴细胞、ABO红细胞、骨髓细胞、二倍体成纤维细胞及经检测的其他肿瘤细胞均无反应。PD4抗原主要表达于靶细胞的膜上,不耐热,为分子量40kD的蛋白性抗原。该抗原与HLA抗原系统,血型抗原系统无关,亦不同于其他作者所报告的其他胃癌相关抗原。 相似文献
47.
用放射免疫成斑法研究了甲型肝炎病毒FM-175株的理化稳定性和灭活条件,证明甲型肝炎病毒理化稳定性与其它肠道病毒相似,具有广范围的pH(2~10)稳定性;Mg~(++)和Ca可增强其热稳定性,不能抵抗冷冻干燥,但对热的抵抗力明显高于普通肠道病毒,可被紫外线迅速杀灭,也可被多种消毒剂如3~8%的甲醛液,50~90%的乙醇,2%的石炭酸及400ppm的有效氯等杀灭,但可抵抗0.1%甲醛液,2~5%的来苏儿及200ppm的有效氯1小时以上,本研究工作为甲型肝炎病毒的理化性状、保存及消毒条件等提供了实验数据。 相似文献
48.
棕色固氮菌中电子载体Fld直接向固氮酶铁蛋白传递电子。Fld_(ox)至Fld_R是双电子二步还原反应,极谱半波电位分别为-210、-550 mV。Fld_(ox)至Fld_(SR)的中点电位为-280 mV,Fld_(SR)至Fld_R为-500mV。铁蛋白中点电位为-256mV,加MgATP后为-390 mV。Fld_R与铁蛋白ox组成的电池电动势为244mV,电子传递可自发进行,反应的J△G~o为-23KJ/摩尔,铁蛋白被Fld_R还原的K_a=1.3×120~4,加入MgATP后△G~o为-10.6KJ/摩尔,K_a=72。因此,未加入MgATP时电子传递反应更易进行。 相似文献
49.
Summary A prospective randomized trial compared the administration of intrapleural plus intravenous Corynebacterium parvum (C. parvum) versus placebo in patients with resected Stage I and Stage II non-small cell bronchogenic carcinoma. Treatment consisted of 7 mg C. parvum injected into the pleural space and 7 mg C. parvum intravenously once between days 6 and 12 postoperatively and 7 mg intravenously every 3rd month during the 1st year. Intrapleural administration of 35 cc of saline served as the placebo and the flush after intrapleural C. parvum.Of the 303 patients entered into this study, 286 were evaluable, with an average follow-up time of 3.5 years. More complications, especially fever, were observed in patients receiving C. parvum. A fever greater than 38 °C was observed in 9% of the patients assigned to placebo and 76% of the patients assigned to C. parvum. There was no significant difference between the treatments with respect to disease-free interval or survival.M. Kaufmann, J. Stjernswärd**, A. Zimmermann (Ludwig Institute for Cancer Research, Bern Branch); K. Stanley**, M. Isley, M. Zelen (Frontier Science & Tech. Research Foundation, Brookline, MA, USA); C. Mouritzen, P. Paulsen, U. Henriques (Dept. of Thoracic and Cardiovascular Surgery and Institute of Pathology, Kommunehospital, Aarhus, Denmark); N. Konietzko, W. Maassen, W. Hartung, W. Wierich (Ruhrland Clinic, Essen-Heidhausen, and Pathology Institute, Ruhr-University, Bochum, FRG); P. Oehl (Innere Klinik und Poliklinik Tumorforschung, Essen, FRG); J. Vogt-Moykopf, H. Toomes, W. Hofmann (Rohrbach Hospital, Clinic for Thoracic Medicine and Pathology Institute, Heidelberg, FRG); F. Krause, R. Rios, R. Spanel (Klinik Löwenstein, Löwenstein, and Pathology Institute, Ulm, FRG); J. Orel, B. Hrabar, D. Ferluga, T. Rott (University Medical Center, Thoracic Surgery and Pathology, Ljubljana, Yugoslavia); H. A. Rostad, J. R. Vale, P. Lexow (Rikshospital, Oslo, Norway); S. Hagen, S. Birkeland (Ulleval Hospital, Oslo, Norway); T. Harbitz, R. Nissen-Meyer (Aker Hospital, Oslo, Norway); E. Aspevik, H. Engedal, A. Mykin (Haukeland Hospital, Bergen, Norway); V. O. Björk, L. Rodriguez, K. Böök, J. Willems (Karolinska Sjukhuset, Thoracic Surgical Clinic and Pathology Department, Stockholm, Sweden); E. Grädel, J. Hasse, P. Dalquen (Kantonsspital, Dept of Surgery, Div. of Cardiac & Thoracic Surgery & Pathology Institute, Basel, Switzerland); L. Eckmann, K. Hänni, K. Zimmermann (Tiefenauspital Surg. Clinic, Univ. of Bern, Switzerland); B. Nachbur, H. U. Würsten, H. Cottier, A. Zimmermann (Inselspital Dept. of Thoracic and Cardiovascular Surg. and Pathology Institute, Bern, Switzerland); W. Maurer, M. Kaufmann (Bürgerspital, Surgical Department, Solothurn, Switzerland); H. Denck, E. Zwintz, St. Wuketich (Krankenhaus der Stadt Wien-Lainz, I. Chir. Dept., and Path. Inst., Vienna, Austria); N. Pridun, H. Hackl (Pulmonologisches Zentrum der Stadt Wien, and Path. Inst., Vienna, Austria); E. Moritz, W. Schlick, H. Holzner (II. Chir. University Clinic and Path. Inst., Vienna, Austria); K. Karrer (Institute for Cancer Research, Vienna, Austria); R. G. Crispen (ITR-Biomedical Research, University of Illinois, Chicago, USA); D. S. Freestone, R. Bomford, M. T. Scott, T. Priestman, L. Toy (The Wellcome Research Laboratories, Beckenham, England)** Present address: Cancer Unit, World Health Organization, Geneva, Switzerland
Offprint requests to: K. Stanley, Ludwig Institute for Cancer Research, Inselspital, CH-3010 Bern, SwitzerlandLudwig Lung Cancer Study Group: 相似文献
50.
酪氨酸对大鼠离体Leydig细胞睾酮和cAMP生成的影响 总被引:2,自引:0,他引:2
本实验采用胶原酶消化,Ficoll 密度梯度离心,制备大鼠睾丸 Leydig 细胞悬浮液进行体外培养(每管内含有10~6 细胞),以研究酪氨酸对 Leydig 细胞睾酮和cAMP 生成的影响。实验结果表明,hCG(100mIU)能明显地促进Leydig 细胞睾酮和 cAMP的生成。睾酮从对照组的3.08±0.58ng(X±SD,下同)增加到41.61±1.52ng,cAMP 含量从19.62±2.56pmol增加到153.24±5.92pmol。若将酪氨酸(60μg)与hCG同时加入到细胞培养液中,则睾酮和cAMP 含量分别下降到 19.22±.0.52ng(P<0.01)和92.63±6.02pmol(P<0.05)。但是,酪氨酸羟化酶抑制剂(α-甲基酪氨酸)对酪氨酸抗hCG致睾酮生成作用无阻断效应,而酪氨酸对外源cAMP(2.5mM)诱导的睾酮生成,则有明显的抑制作用,睾酮含量从27.56±1.53ng降至 19.50±0.47ng(P<0.01)。以上实验结果表明,酪氨酸抗hCG致睾酮生成的作用机理与cAMP有关。 相似文献