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排序方式: 共有397条查询结果,搜索用时 15 毫秒
331.
The effect of body size on various hematological variables was examined in juvenile shortnose sturgeon (Acipenser brevirostrum) ranging in mass from 38 to 730 g. The blood was examined for differences in plasma ionic composition (Na+, K+, Cl?), blood oxygen carrying capacities (hemoglobin, hematocrit), and plasma metabolite concentrations (lactate, glucose), before and following a standard 5‐min chasing stress. All measured resting hematological variables were size independent in shortnose sturgeon. After exercise, levels of plasma lactate, potassium, and hemoglobin increased in all fish. Only post‐exercise levels of chloride and hemoglobin changed in a size‐dependent manner; however, the relationships were weak. The general lack of a relationship between body size and hematological variables might reflect the narrow range of fish sizes used in the present study. From a practical perspective, the results suggest that when examining the hematological stress response in juvenile shortnose sturgeon, a range of fish sizes could be used. This is important considering the variability in the growth rates of juvenile shortnose sturgeon under laboratory conditions. 相似文献
332.
Marije B Overdijk Sandra Verploegen Marijn B?gels Marjolein van Egmond Jeroen J Lammerts van Bueren Tuna Mutis Richard WJ Groen Esther Breij Anton CM Martens Wim K Bleeker Paul WHI Parren 《MABS-AUSTIN》2015,7(2):311-320
Daratumumab (DARA) is a human CD38-specific IgG1 antibody that is in clinical development for the treatment of multiple myeloma (MM). The potential for IgG1 antibodies to induce macrophage-mediated phagocytosis, in combination with the known presence of macrophages in the tumor microenvironment in MM and other hematological tumors, led us to investigate the contribution of antibody-dependent, macrophage-mediated phagocytosis to DARA''s mechanism of action. Live cell imaging revealed that DARA efficiently induced macrophage-mediated phagocytosis, in which individual macrophages rapidly and sequentially engulfed multiple tumor cells. DARA-dependent phagocytosis by mouse and human macrophages was also observed in an in vitro flow cytometry assay, using a range of MM and Burkitt''s lymphoma cell lines. Phagocytosis contributed to DARA''s anti-tumor activity in vivo, in both a subcutaneous and an intravenous leukemic xenograft mouse model. Finally, DARA was shown to induce macrophage-mediated phagocytosis of MM cells isolated from 11 of 12 MM patients that showed variable levels of CD38 expression. In summary, we demonstrate that phagocytosis is a fast, potent and clinically relevant mechanism of action that may contribute to the therapeutic activity of DARA in multiple myeloma and potentially other hematological tumors. 相似文献
333.
334.
EG Ciolac SS Mantuani CM Neiva CEL Verardi DM Pess?a-Filho L Pimenta 《Biology of sport / Institute of Sport》2015,32(2):103-108
The aim of the present study was to analyse the usefulness of the 6-20 rating of perceived exertion (RPE) scale for prescribing and self-regulating high-intensity interval training (HIT) in young individuals. Eight healthy young subjects (age = 27.5±6.7 years) performed maximal graded exercise testing to determine their maximal and reserve heart rate (HR). Subjects then performed two HIT sessions (20 min on a treadmill) prescribed and regulated by their HR (HR: 1 min at 50% alternated with 1 min at 85% of reserve HR) or RPE (RPE: 1 minute at the 9-11 level [very light-fairly light] alternated with 1 minute at the 15-17 level [hard-very hard]) in random order. HR response and walking/running speed during the 20 min of exercise were compared between sessions. No significant difference between sessions was observed in HR during low- (HR: 135±15 bpm; RPE: 138±20 bpm) and high-intensity intervals (HR: 168±15 bpm; RPE: 170±18 bpm). Walking/running speed during low- (HR: 5.7±1.2 km · h−1; RPE: 5.7±1.3 km · h−1) and high-intensity intervals (HR: 7.8±1.9 km · h−1; RPE: 8.2±1.7 km · h−1) was also not different between sessions. No significant differences were observed in HR response and walking/running speed between HIT sessions prescribed and regulated by HR or RPE. This finding suggests that the 6-20 RPE scale may be a useful tool for prescribing and self-regulating HIT in young subjects. 相似文献
335.
Ting Y. Wong Alexander M. Horspool Brynnan P. Russ Chengjin Ye Katherine S. Lee Michael T. Winters Justin R. Bevere Olivia A. Miller Nathaniel A. Rader Melissa Cooper Theodore Kieffer Julien Sourimant Alexander L. Greninger Richard K. Plemper James Denvir Holly A. Cyphert Mariette Barbier Jordi B. Torrelles Ivan Martinez Luis Martinez-Sobrido F. Heath Damron 《Journal of virology》2022,96(6)
336.
An extract from rat brain has been shown to catalyze the transfer of ganglioside GM1 from sonicated vesicles to erythrocyte ghosts. It also enhanced the transfer of GM1 to a crude neuronal membrane preparation, whereas myelin took up only a very limited amount. The transfer activity was heat-labile. Similar transfer activities were found in extracts from bovine gray and white matter, that of the former being comparable to rat brain whereas the latter was greater per milligram protein. 相似文献
337.
R H Wenger N Kieffer A N Wicki K J Clemetson 《Biochemical and biophysical research communications》1988,156(1):389-395
The gene for human platelet glycoprotein Ib alpha-chain has been cloned from a genomic cosmid library using a partial cDNA clone as probe. 3530 bp were sequenced including the entire transcribed part, as well as additional 5' and 3' regions. A single intron was found 6 bp upstream of the ATG initiation codon. An exceptionally long exon was identical to the recently published cDNA sequence (1). The 5' upstream promoter region is atypical for eukaryotic genes with only a weak homology to the characteristic promoter consensus sequences. The 3' region contains two repetitive Alu elements, belonging to distinct subfamilies, connected by an oligo(dA) linker. 相似文献
338.
Identification of platelet membrane thrombospondin binding molecules using an anti-thrombospondin antibody 总被引:2,自引:0,他引:2
N Kieffer A T Nurden M Hasitz M Titeux J Breton-Gorius 《Biochimica et biophysica acta》1988,967(3):408-415
A rat monoclonal IgG2a antibody, 5G11, was raised against native human platelet thrombospondin (TSP). Western blot analysis revealed that 5G11 bound (i) to TSP before and after disulfide reduction, and (ii) to a 15-kDa fragment released after prolonged trypsin digestion. Crossed immunoelectrophoresis confirmed that the binding epitope was expressed in the presence of Ca2+ and after treatment of TSP with EDTA. Since 5G11 had no effect on platelet aggregation, the antibody was used to immunoprecipitate Ca2+-dependent and Ca2+-independent TSP-binding molecules on the surface of thrombin-activated surface-labeled 125I-platelets. The experimental basis was that ligand-receptor interactions are of high affinity and that anti-ligand antibodies should precipitate the ligand-receptor complex. With platelets activated in the presence of EDTA, 5G11 predominantly precipitated a 125I-labeled band of Mr 88,000, identified as glycoprotein (GP) IV. In contrast, in the presence of 2 mM Ca2+ and 1 mM Mg2+, 5G11 precipitated a complex of five radiolabeled proteins, among which GPIIb, GPIIIa and GPIV were the most prominent. 相似文献
339.
Brassica oleracea L. is highly polymorphic and includes varieties which exhibit a headed phenotype (a large preinflorescence): the curd of
cauliflower and `romanesco' (var. botrytis), and the spear of broccoli (var. italica). This headed phenotype results from highly iterative patterns of activity at the primary meristems. Differences in the morphology
of curds and spears are accounted for by three quantitative variables: the rate of production of branch primordia on the flanks
of the apical meristems (RPP); the number of branch primordia produced before the first formed begin producing their own branch
primordia (the iteration interval, ITI); and the duration of the preinflorescence stage (before production of flower primordia).
Relatively stable iteration parameters (RPP and ITI) during curd development lead to the production of semi-spherical curds
with a smooth surface in cauliflower and broccoli, whereas in `romanesco' RPP and ITI increase throughout curd development,
inducing a pyramidal curd with an angular surface. A relatively long preinflorescence stage in cauliflower and `romanesco'
results in the curd surface being composed largely of branch primordia, whereas in broccoli this stage is short and the spear
surface is made up of flower buds. Simplified growth models for these three headed types are presented. The implications for
the genetic control of the B. oleracea L. headed phenotype and the relationships between shoot apical meristem size, phyllotaxis and curd/spear morphology are discussed.
Received: 11 September 1997 / Accepted: 12 November 1997 相似文献
340.
Conservation of alternative splicing and genomic organization of the myosin alkali light-chain (Mlc1) gene among Drosophila species 总被引:3,自引:0,他引:3
The Mlc1 gene of Drosophila melanogaster encodes two MLC1 isoforms via
developmentally regulated alternative pre-mRNA splicing. In larval muscle
and tubular and abdominal muscles of adults, all of the six exons are
included in the spliced mRNA, whereas, in the fibrillar indirect flight
muscle of adult, exon 5 is excluded from the mRNA. We show that this
tissue-specific pattern of alternative splicing of the Mlc1 pre-mRNA is
conserved in D. simulans, D. pseudoobscura, and D. virilis. Isolation and
sequencing of the Mlc1 genes from these three other Drosophila species have
revealed that the overall organization of the genes is identical and that
the genes have maintained a very high level of sequence identity within the
coding region. Pairwise amino acid identities are 94%-99%, and there are no
charge changes among the proteins. Total nucleotide divergence within the
coding region of the four genes supports the accepted genealogy of these
species, but the data indicate a significantly higher rate of amino acid
replacement in the branch leading to D. pseudoobscura. A comparison of
nucleotide substitutions in the coding portions of exon 5 and exon 6, which
encode the alternative carboxyl termini of the two MLC1 isoforms, suggests
that exon 5 is subject to greater evolutionary constraints than is exon 6.
In addition to the coding sequences, there is significant sequence
conservation within the 5' and 3' noncoding DNA and two of the introns,
including one that flanks exon 5. These regions are candidates for cis-
regulatory elements. Our results suggest that evolutionary constraints are
acting on both the coding and noncoding sequences of the Mlc1 gene to
maintain proper expression and function of the two MLC1 polypeptides.
相似文献