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41.
A submicromolar assay for nonpolar acids in plasma and depot fat 总被引:1,自引:0,他引:1
42.
43.
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
44.
45.
Transposition, amplification, and divergence in the origin of the DNF15 loci, a polymorphic repetitive sequence family on chromosomes 1 and 3 总被引:4,自引:0,他引:4
The loci DNF15S1 and DNF15S2 are members of a small repetitive sequence family at discrete chromosomal locations, namely, 1p36 and 3p21, respectively. Studies of the structure, arrangement, and interrelations of the family suggest that the single copy on chromosome 3 is the original member and that this gave rise to the several members on chromosome 1 by transposition, partial duplication, and amplification. Several restriction fragment length polymorphisms have been discovered at the DNF15S1 locus and these have been assigned to the different subfamilies of the repeat at this locus. The existence of these RFLPs, and the nonallelic restriction site variation also found in this sequence family, suggests that transposition and amplification occurred as discrete events. We sequenced across the ancient junction between chromosomes 1 and 3 and noted features which might explain the mechanics of the transposition and amplification events. 相似文献
46.
Isolation of Glutamyltaurine from Bovine Brains and Proof of Its γ-Linkage by the B/E Linked Scan SIMS Technique 总被引:1,自引:1,他引:0
Ko Nakamura Kunihiko Higashiura Naoharu Nishimura Atsushi Yamamoto Ikuo Tooyama Hiroshi Kimura Kazuharu Ienaga 《Journal of neurochemistry》1990,55(3):1064-1066
We isolated a glutamyltaurine from bovine brains and determined its structure as gamma-glutamyltaurine (gamma-Glu-Tau; glutaurine) by use of a new mass spectrometric technique [B/E linked scan sputtered ion mass spectrometry (SIMS)], which we have recently shown to be useful for distinguishing the gamma- from the alpha-isomer of glutamyl-dipeptides. Neither the alpha-isomer of glutamyltaurine nor any aspartyltaurines could be detected in bovine brain. 相似文献
47.
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
48.
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
49.
The effects of alpha-adrenoreceptor antagonists prazosin (alpha-1), yohimbine (alpha-2), and idazoxan (alpha-2) on xylazine-induced bovine uterine contractility were tested in vitro. Uterine strips from proestrous/estrous and diestrous cows were mounted in tissue baths containing Tyrode's solution. Changes in uterine contractility were measured by strain gauge. The following results were observed: 1) Xylazine increased uterine contractility in a dose dependent manner (cumulative concentrations: 10(-8), 3x10(-8), 10(-7), 3x10(-7) and 10(-6)M). 2) Idazoxan (10(-8), 10(-7) and 10(-6)M) and yohimbine (10(-6), 10(-5) and 10(-4)M) antagonized uterine contractility induced by xylazine in a dose-dependent manner. Idazoxan was approximately 50 to 100 times more potent than yohimbine. 3) Prazosin (10(-5)M) did not alter the effect of xylazine on uterine contractility. These results suggested that xylazine-induced uterine contractility in the cyclic cow is directly mediated by myometrial alpha-2 adrenoreceptors. 相似文献
50.
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