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81.
K H?kkinen M Alén P V Komi 《European journal of applied physiology and occupational physiology》1984,53(2):97-105
Various aspects of neuromuscular, anaerobic, and aerobic performance capacity were investigated in four powerlifters, seven bodybuilders, and three wrestlers with a history of specific training for several years. The data (means +/- SD) showed that the three subject groups possessed similar values for maximal isometric force per unit bodyweight (50.7 +/- 9.6, 49.3 +/- 4.1, and 49.3 +/- 10.9 N/kg, respectively). However, significant (P less than 0.05) differences were observed in the times for isometric force production, so that e.g., times to produce a 30% force level were shorter for the wrestlers and bodybuilders (28.3 +/- 3.1 and 26.4 +/- 6.6 ms) than that (53.3 +/- 23.7 ms) for the powerlifters. Utilization of elastic energy by the wrestlers was significantly (P less than 0.05) better than that of the other two subject groups, as judged from differences between the counter-movement and squat jumps at 0, 40, and 100 kg's loads. No differences were observed between the groups in anaerobic power in a 1-min maximal test, but the values for VO2 max were higher (P less than 0.05) among the wrestlers and bodybuilders (57.8 +/- 6.6 and 50.8 +/- 6.8 ml X kg-1 X min-1) as compared to the powerlifters (41.9 +/- 7.2 ml X kg-1 X min-1). Within the limitations of the subject sample, no differences of a statistical significancy were observed between the groups in fibre distribution, fibre areas, or the area ratio of fast (FT) and slow (ST) twitch fibres in vastus lateralis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
82.
P Couillin R Mollicone M C Grisard A Gibaud N Ravisé J Feingold R Oriol 《Cytogenetics and cell genetics》1991,56(2):108-111
Seventy-one human x mouse hybrid cell lines were used to map the locus of a human alpha-3-fucosyltransferase to 11q. The enzyme transfers fucose onto H type 2 more efficiently than onto sialyl-N-acetyllactosamine, suggesting that it is the myeloid type of alpha-3-fucosyltransferase (Mollicone et al., 1990), which makes the 3-fucosyllactosamine epitope on polymorphonuclear cells and monocytes. This epitope is also known as CD15 (Tetteroo et al., 1987). 相似文献
83.
Cationic amphiphile-mediated delivery of plasmid DNA is the non-viral gene transfer method most often used. In the present work, we considered a new cysteine-detergent, ornithinyl-cysteinyl-tetradecylamide (C(14)-CO), able to convert itself, via oxidative dimerization, into a cationic cystine-lipid. By using fluorescence techniques, we first characterized the structure of complexes of plasmid DNA with C(14)-CO molecules either kept as monomers, or oxidized into dimers. Both forms are able to condense DNA, with the formation of hydrophobic micelle-like domains along the DNA chain. Domains with a larger molecular order were obtained with dimeric C(14)-CO/DNA complexes. In a second step, the interactions of these complexes with lipid vesicles considered as membrane models were investigated. In the presence of vesicles, we observed a decondensation of the DNA involved in complexes obtained with C(14)-CO monomers. With anionic vesicles, the DNA is released into the bulk solution, while with neutral vesicles, it remains bound to the vesicles via electrostatic interactions with inserted C(14)-CO molecules. In sharp contrast, the complexes with C(14)-CO dimers are unaffected by the addition of either neutral or anionic vesicles and show no interaction with them. These results may partly explain the low transfection efficiency of these complexes at the +/-charge ratios used in this study. 相似文献
84.
Pascal Griesmar Clément Sanchez Germain Puccetti Isabelle Ledoux Joseph Zyss 《Molecular Engineering》1991,1(3):205-220
Orientation of optically nonlinear organic molecules inside sol-gel matrices upon application of an external D.C. electrical field is demonstrated for the first time. The quadratic nonlinear response of silicon oxide or transition metal oxide based gels containing organic molecules has been determined from Electric Field Induced Second Harmonic (EFISH) measurements. Large concentrations of Optically Nonlinear Organic Molecules (ONOM) have been either incorporated inside the macromolecular network or chemically bonded to the oxide backbone of the gels. These results demonstrate the feasibility of permanently poled doped sol-gel matrices. Moreover, EFISH measurements performed on organic molecules appear to be a useful tool for monitoring the changes occurring during sol-gel transformations. 相似文献
85.
The phenotypic consequences in the house mouse (Mus musculus domesticus) of the transition from an ordinary field-dwelling rodent to a species that is dependent on human populations was studied by investigating the morphometric variation of non-commensal populations of M. m. domesticus from Syria, Jordan, SW Iran, and Libya and comparing them with that of conspecific commensal populations from Eastern Turkey, Greece, and Bulgaria. Commensal populations of M. musculus musculus from the Czech Republic were used as an outgroup. About 849 adult specimens of M. musculus were analysed by multivariate procedures based on standard molar, skull and body measurements. As expected, there was considerable variation among the studied populations and a good correspondence between morphometric and geographic distances. The resulting morphometric tree was consistent with the hypothesis that the original radiation of M. m. domesticus took place somewhere in the Near East. Commensal populations of M. m. domesticus form a single derived branch. Specimens originating from four different sites in eastern Syria showed the greatest similarity to one another and possessed relatively bigger molars than the other studied populations. Commensal populations were characterised by longer tails when compared to non-commensal populations, which suggests an adaptation for living in a more three-dimensionally heterogeneous environment for commensal populations. 相似文献
86.
Fátima H. Vaz Patrícia M. Machado Rita D. Brand?o Cátia T. Laranjeira Joana S. Eugénio Aires H. Fernandes Saudade P. André 《The journal of histochemistry and cytochemistry》2007,55(11):1105-1113
Only 20-25% of families screened for BRCA1/2 mutations are found positive. Because only a positive result is informative, we studied the role of BRCA1/2 immunohistochemistry as an additional method for patient selection. From 53 high-risk-affected probands, 18 (34%) had available paraffin blocks of their tumors and were selected for this study. Mutation screening was done by conformation-sensitive gel electrophoresis and multiplex ligation-dependent probe amplification. For immunohistochemistry, 21 neoplastic specimens (15 breast carcinomas, 5 ovary neoplasms, and 1 rectal adenocarcinoma) were analyzed with BRCA1 (monoclonal antibody, Ab-1, oncogene) and BRCA2 (polyclonal antibody, Ab-2, oncogene) antibodies. Absence of the BRCA1 protein was confirmed in negative tumors by Western blotting. Seven patients were positive for BRCA1/2 mutations: 5 for BRCA1 and 2 for BRCA2. Four out of five positive patients had tumors negative for BRCA1 immunostaining, and the remaining 13 BRCA1-negative patients had positive BRCA1 immunostaining in all tumor samples. Sensitivity to predict for BRCA1 mutation carriers was 80%, and specificity was 100%, with a positive predictive value of 100% and a negative predictive value of 93%. This correlation was statistically significant (p=0.001). No correlation was observed for BRCA2. If larger studies confirm these results, high-risk patients with BRCA1-negative tumors should be screened first for this gene. 相似文献
87.
J M Gallo D Escalier P Grellier E Précigout M Albert G David J Schrével 《The journal of histochemistry and cytochemistry》1991,39(3):273-282
Among the monoclonal antibodies (MAb) selected after immunization of mice with a detergent-insoluble fraction from human spermatozoa, MAb 4D4 was found to stain in immunofluorescence the principal part of the acrosome of human spermatozoa. Acrosome reaction induced decreased and spotty 4D4 immunofluorescence staining. Immunoelectron microscopy before or after embedding revealed that the epitope defined by MAb 4D4 was sequestered in the anterior acrosomal matrix and, after the acrosome reaction, remained partly bound on matrix elements attached to the inner acrosomal membrane. Western blot analysis of sperm extracts showed that the epitope defined by MAb 4D4 was located on a 55 KD polypeptide in whole cells and on 55 and 50 KD polypeptides in non-ionic detergent fractions. Human proacrosin-enriched fraction obtained by FPLC purification exhibited several proteolytic activities against gelatin in gel enzymography: a 50 KD major band and two minor bands in the 20-30 KD area; the 50 KD polypeptide reacted with MAb 4D4 in Western blots. Furthermore, the 4D4-immunoprecipitated polypeptide from sperm extract showed that the 50 KD band exhibited proteolytic activity with an optimal pH at 8.0 that was strongly inhibited by soybean trypsin inhibitor and ZnCl2. MAb 4D4 also reacted with the acrosome of the monkey Macaca fascicularis but not with the acrosome of any of the other non-primate mammalian species examined so far. Various shape defects of the acrosomal principal region were revealed by 4D4 labeling of spermatozoa with head anomalies from infertile patients. MAb 4D4 also recognized proacrosin in paraffin-embedded human testis sections. These data make the monoclonal antiproacrosin antibody 4D4 an efficient tool for evaluation of the acrosomal status of human spermatozoa and spermatids. 相似文献
88.
J J Candelier P Couillin P Eydoux A Boué 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1986,302(8):303-308
The production of monoclonal antibodies against human embryonic renal cells allowed to display on the adult human kidney some antigens typical of certain structures or tissues: the proximal convoluted tubule for EG 9-11 and EG 19-6 monoclonal antibodies, the glomerular basement membrane for EG 14-1, the urothelium for EE 24-6, the connective tissue for EK 8-1 and EK 17-1 and probably the capsular and tubular basement membranes for EK 8-1. Simultaneously, we could follow the spatial and temporal repartition of the antigens during the renal development. One of them (EI 16-1) seemed to disappear in the adult and might correspond to a foetal type-antigen. 相似文献
89.
An Na+-stimulated Mg2+-transport system in human red blood cells 总被引:5,自引:0,他引:5
The initial rate of net Mg2+ efflux was measured in human red blood cells by atomic absorption. In fresh erythrocytes incubated in Na+,K+-Ringer's medium this rate was 7.3 +/- 2.8 mumol/l cells per h (mean +/- S.D. of 14 subjects) with an energy of activation of 13 200 cal/mol. Cells with total Mg2+ contents ([ Mg]i) ranging from 1.8 to 24 mmol/l cells were prepared by using a modified p-chloromercuribenzenesulphonate method. Mg2+ efflux was strongly stimulated by increases in [Mg]i and in external Na+ concentrations ([ Na]o). A kinetic analysis of Mg2+ efflux as a function of [Mg]i and [Na]o revealed the existence of two components: an Na+-stimulated Mg2+ efflux, which exhibited a Michaelian-like dependence of free internal Mg2+ content (apparent dissociation constant = 2.6 +/- 1.4 mmol/l cells; mean +/- S.D. of six subjects) and on external Na+ concentration (apparent dissociation constant = 20.5 +/- 1.9 mM; mean +/- S.D. of four subjects) and a variable maximal rate ranging from 35 to 370 mumol/l cells per h, and an Na+-independent Mg2+ efflux, which showed a linear dependence on internal Mg2+ content with a rate constant of (6.6 +/- 0.7) X 10(-3) h-1. Fluxes catalyzed by the Na+-stimulated Mg2+ carrier were partially dependent on the ATP content of the cells and completely inhibited by quinidine (IC50 = 50 microM) and by Mn2+ (IC50 = 0.5-1.0 mM). 相似文献
90.