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981.
S V Khabarov 《Biulleten' eksperimental'no? biologii i meditsiny》1987,103(6):715-717
Beta-adrenoceptors have been discovered on the surface of cells of leukaemia L1210 and its variant resistant to sarcolysine (D, L-melphalan). One type of functionally active receptors with dissociation constant Kd for L-[3H] dihydroalprenolol about 0.02 nM and 360 receptors per cell have been revealed in leukaemia L1210 cells. In the resistant cells two types of functionally inactive receptors with Kd1 approximately 0.02 nM (420 receptors per cell) and Kd2 approximately 2.5 nM (3000 receptors per cell) have been revealed. This property of beta-adrenoceptors may be one of the causes of tumour cell resistance to sarcolysine. 相似文献
982.
D. R. Gustafsson L. Lei K. Luo X. Chu X. Zhao Q. Zhang F. Zou 《Medical and veterinary entomology》2019,33(3):407-419
In total, 366 birds representing 55 species in 24 families and eight orders, were examined for chewing lice (Phthiraptera: Amblycera, Ischnocera) in two high‐altitude localities in Yunnan Province, China. In Ailaoshan, almost all of the birds examined were resident passeriforms, of which 36% were parasitized by chewing lice. In Jinshanyakou, most birds were on migration, and included both passerine and non‐passerine birds. Of the passerine birds caught in Jinshanyakou, only one bird (0.7%) was parasitized by chewing lice. The prevalence of Myrsidea and Brueelia‐complex lice on birds caught in Ailaoshan was higher than in previous reports. Of the chewing lice identifiable to species level, three represent new records for China: Actornithophilus hoplopteri (Mjöberg, 1910), Maculinirmus ljosalfar Gustafsson & Bush, 2017 and Quadraceps sinensis Timmermann, 1954. In total, 17 new host records are included, of which we describe two as new species in the Brueelia‐complex: Guimaraesiella (Cicchinella) ailaoshanensis sp. nov. ex Schoeniparus dubius dubius (Hume, 1874) and G. (C.) montisodalis sp. nov. ex Fulvetta manipurensis tonkinensis Delacour & Jabouille, 1930. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:9FC3D8EE‐2CED‐4DBE‐A1DB‐471B71260D27 . 相似文献
983.
984.
985.
986.
L V Gankovskaia A Z Tskhovrebova N A Gvozdeva L V Koval'chuk A N Cheredeev 《Biulleten' eksperimental'no? biologii i meditsiny》1986,102(8):210-213
Fractions containing macrophage migration inhibition factor (MIF) and leucocyte migration inhibition factor (LIF) were obtained using Sephadex G-200 filtration from supernatant fluids of human lymphocyte cultures stimulated by PHA. The fractions were tested for the ability to affect migration and phagocytic activity of target cells. Peripheral blood leucocyte migration capacity was inhibited by the fraction with the molecular mass of 60,000-70,000 D (LIF), while migration activity of mouse peritoneal exudate cells was suppressed by the fraction with the molecular mass of 20,000-30,000 D (MIF). MIF- and LIF-containing fractions increased almost three-fold Fc-receptor-mediated phagocytic activity of neutrophils. 相似文献
987.
R Foa M T Fierro M Giovarelli P Lusso G Benetton M Bonferroni G Forni 《Blood cells》1987,12(2):399-412
Several phenotypic and functional defects have been described within the residual T-lymphocyte population of patients with B-cell chronic lymphocytic leukemia (B-CLL), particularly in those in the more advanced stages of the disease. In this study, we review these abnormalities and discuss their possible effects on the course of the illness. Particular emphasis is devoted to the role of interleukin 2 (IL-2) in B-CLL. Evidence is provided that the IL-2 released by B-CLL T-lymphocytes may be utilized by the neoplastic B-cell clone that expresses the IL-2 receptor and that decreased availability of IL-2 may play a contributory role in some of the T-cell defects encountered in B-CLL. 相似文献
988.
The isolation of spirochaetes from the rat caecum 总被引:1,自引:1,他引:0
Spirochaetes indigenous to the conventional rat caecum were cultivated on agar medium using selective isolation techniques. The 27 axenic isolates represented four morphological types of spirochaetes differing in cell size, cell coiling pattern and number of protoplasmic flagella. 相似文献
989.
990.
Plasma concentrations of adrenaline and noradrenaline were measured at rest from cannulated fish and following net capture. Adrenaline and noradrenaline concentrations in capture-stressed fish averaged 36,740 pmol l-1 and 38,860 pmol l-1 respectively, whereas resting values were less than 200 pmol l-1 for both amines. Erythrocyte swelling and raised blood lactate were evident in stressed fish. In vitro effects of 5 mmol l-1 adrenaline on erythrocyte suspensions suggested that the catecholamine had a direct effect on erythrocyte volume. The significance of these results is discussed in relation to the oxygen transport properties of the blood. 相似文献