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31.
32.
Antiserum был подготовлен противингибитор вируса haemagglutination (IVH)одна из эмбриона chorioallantoic мембр анныепутем иммун изации морских св инокЭто анти-инги битора в сыворотке заблокирован ингибирование IVH из chorioallantoicмембран в haemagglutination испытанияно ника кого влияния на ре цепторы эритроци товСыворотке кро] ви не влияет рост chorioallantoic мембраны клет ок инет нейтрализ овать воздействи е на вирус гриппа Она снизилась спо собность chorioallantoic мембр ан для adsorb вируса гри ппа, а также степен ь размножения вир усав такого рода тканиАвторы хоте ли бы поблагодари ть г-н Г. Ruttkay-Ne -палубе и для проведения эле ктрофореза меру ния. 相似文献
33.
34.
Hak Ryul Kim Sook J. Seo Richard T. Mayer 《Archives of insect biochemistry and physiology》1989,10(3):215-228
Two kinds of storage proteins (SP-1, SP-2) were confirmed in hemolymph and fat body of Pieris rapae during metamorphosis. Both proteins were present in high concentrations in the hemolymph during the last larval instar. Hemolymph concentrations of SP-1 and SP-2 dropped after pupation as the proteins were being deposited in fat bodies. SP-2 is present in a larger amount than SP-1. Detailed studies on storage proteins determined their properties, mode of synthesis, and accumulation in the fat body. SP-1 has a molecular weight of 500,000 and consists of one type of subunit (Mr 77,000), while SP-2 has a molecular weight of 460,000 and is composed of two types of subunits (Mr 80,000 and 69,000). The pl values of SP-1 and SP-2 were determined to be 6.97 and 7.06, respectively. Fat body cells from 1-day-old fifth instar larvae synthesized storage proteins in large amounts, whereas those from late prepupae exhibited high protein sequestration. Proteins taken up in fat body accumulated in dense granules during the pupal stage but sharply decreased at the adult stage. Morphological changes in the fat body tissues were observed during the larval-pupal transformation; the nuclei of fat body cells became irregularly shaped, and the boundaries between cells seemed to be obscure. Synthesis, storage, or degradation of storage proteins in fat body during development is closely associated with morphological changes in the tissues. 相似文献
35.
36.
Multiple T and B cell epitopes in the S1 subunit ("A"-monomer) of the pertussis toxin molecule 总被引:5,自引:0,他引:5
J R Oksenberg C Ko A K Judd M Lim A Kent G K Schoolnik L Steinman 《Journal of immunology (Baltimore, Md. : 1950)》1989,143(12):4227-4231
The immunogenicity and reactogenicity of Bordetella pertussis vaccine are mediated in part by the S1 subunit of pertussis toxin (PT). To identify the immune epitopes in the S1 subunit of PT, synthetic peptides were prepared and tested for their capacity to induce antibodies in mice with different MHC genotypes. In BALB/c mice, peptides corresponding to sequences 1-17, 70-82 and 189-199 generate T cell proliferative responses, induce the production of antibodies capable of neutralization of the toxin in the Chinese hamster ovary-cell assay, and protect mice from a shock-like syndrome caused by alternate injections of BSA and PT. Protection and neutralization correlated with the ability of these peptides to elicit high anti-PT titers. Different B cell epitopes were detected in other inbred mouse strains. The antibody reactivity against synthetic peptides from two infants vaccinated with pertussis vaccine was tested. These infants had antibodies reactive to a variety of epitopes in the S1 subunit, including peptides 1-17, 70-82, 99-112, 135-145, and 189-199. Thus, it appears that there are multiple T and B cell epitopes in the S1 subunit of PT. 相似文献
37.
J Yoon R D Shortridge B T Bloomquist S Schneuwly M H Perdew W L Pak 《The Journal of biological chemistry》1989,264(31):18536-18543
38.
M a Belen'ki? S Bountzioukas G Gonzales D Ko K Lederis A L Polenov 《Zhurnal evoliutsionno? biokhimii i fiziologii》1990,26(3):340-346
A significant increase of the content of corticosterone in the blood collected from intravenous cannula or by intracardiac punction has been detected using radioimmunoassay in non-operated and adenohypophysectomized frogs Rana catesbeiana subjected to dehydration in 6.2% mannitol solution during 24 hours. The osmolality of the blood plasma of these animals also increases although less significantly than the growth of plasma corticosterone content. There is a tendency to substantial increase of plasma arginine-vasotocin level prior to the growth of corticosterone level, already after 6 hours of dehydration. Based on the present results and literature data, it is suggested that in adenohypophysectomized frogs lacking endogenous ACTH just the increase of blood arginine-vasotocin level results in a substantial activation of corticosteroid-producing cells of the interrenal gland and in the growth of plasma content of corticosterone. 相似文献
39.
A. A. J. J. L. Rutten B. G. A. G. G. Béquet-Passelecq H. B. W. M. Koëter 《In vitro cellular & developmental biology. Plant》1990,26(4):353-360
Summary A new method was developed for rabbit skin organ culture. In a two-compartment model, skin discs were cultured on a Millicell-HA
insert unit with a microporous membrane which allows transport of culture medium via the dermis into the epidermis, whereas
the epidermal side remains free of direct contact with culture medium. In this relatively simple two-compartment organ culture
model, rabbit skin could be cultured for 7 d in RPMI 1640 medium supplemented with fetal bovine serum, or for 2 d in RPMI
1640 medium supplemented with cofactors. The histomorphology and ultrastructure of 7-d cultured rabbit skin discs was essentially
similar to that of freshly isolated rabbit skin. Keratinocytes in the stratum basale continued to divide during organ culture.
The terminal differentiation of the epidermis continued in vitro as was found by the presence of keratohyalin granules, the
intact stratum corneum, and keratin expression. Furthermore, glucose consumption continued until culture Day 7, but thereafter
it declined rapidly. Concomitantly, degenerative changes were found. At the end of the 7-d culture period the distance between
single dermal collagen fibrils had increased as compared to noncultured skin. This model of skin organ cultures can be used
to study biological processes, dermal toxicity, and penetration and metabolism of xenobiotics in intact skin. Furthermore,
within certain limits, processes responsible for repair and regeneration of damaged skin can also be studied in this model
because the rabbit skin can be cultured for 7 d.
The present study was financially supported by grants of Duphar B. V. (Weesp, Netherlands), the European Community, and the
Dutch animal welfare organizations Samenwerkingsverband van de Nederlandse Vereniging tot Bescherming van Dieren en de Nederlandse
Bond tot Bestrijding van de Vivisectie, Anti-Vivisectie Stichting en Stichting Schoonheid Zonder Wreedheid. 相似文献
40.
To clarify the way in which the light available for growth affectsrespiration in leaves of sun and shade plants, we examined therespiratory properties of mature leaves of Spinacia oleraceaL., a sun species, and of Alocasia macrorrhiza (L.) G. Don.,a shade species, that had been grown at various irradiances.In leaves of S. oleracea, the respiratory rates, on a dry massbasis, decreased with time during the night, and the higherwas the growth irradiance during the day, the higher was therespiratory rate. The marked decreases in the respiratory rateduring the night were accompanied by decreases in the concentrationof carbohydrates in the leaves. By contrast, the respiratoryrates of leaves of A. macrorrhiza were virtually constant throughoutthe night and the absolute rates were lower than those of S.oleracea even though the absolute value of the concentrationof carbohydrates and its decrease at night resembled to thosein S. oleracea. The maximum activities of respiratory enzymeswere also similar to those in S. oleracea. However, the leavesof A. macrorrhiza contained less soluble protein than thoseof S. oleracea. These results suggest that, in S. oleracea,the concentration of carbohydrates might determine the respiratoryrate while such is not the case in A. macrorrhiza. The lowerrespiratory rates in A. macrorrhiza might be due to a lowerdemand for ATP. (Received November 29, 1995; Accepted February 15, 1996) 相似文献