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排序方式: 共有538条查询结果,搜索用时 15 毫秒
31.
Giménez-Abián JF Clarke DJ Devlin J Giménez-Abián MI De la Torre C Johnson RT Mullinger AM Downes CS 《Chromosoma》2000,109(4):235-244
When DNA topoisomerase II (topo II) activity is inhibited with a non-DNA-damaging topo II inhibitor (ICRF-193), mammalian
cells become checkpoint arrested in G2-phase. In this study, we analyzed chromosome structure in cells that bypassed this
checkpoint. We observed a novel type of chromosome aberration, which we call Ω-figures. These are entangled chromosome regions
that indicate the persistence of catenations between nonhomologous sequences. The number of Ω- figures per cell increased
sharply as cells evaded the transient block imposed by the topo II-dependent checkpoint, and the presence of caffeine (a checkpoint-evading
agent) potentiated this increase. Thus, the removal of nonreplicative catenations, a process that promotes chromosome individualization
in G2, may be monitored by the topo II-dependent checkpoint in mammals.
Received: 19 July 1999; in revised form: 20 October 1999 / Accepted: 7 January 2000 相似文献
32.
Dr. C. Broberger D. Blacker L. Giménez-Llort M. Herrera-Marschitz S. -O. Ögren T. Hükfelt 《Amino acids》1998,14(1-3):25-31
Summary Motor behaviour relies on complex neurochemical interactions in the basal ganglia, in particular the striatum. Antagonistic influences in this region are exerted by afferent projections from, on the one hand, the ventral mesencephalon, utilizing dopamine as a transmitter, and, on the other hand, from the cerebral cortex, signalling by the excitatory amino acid glutamate. The activity in both these neuronal populations appears to be regulated by the neuropeptide cholecystokinin. This article concentrates on interactions between cholecystokinin and glutamate, summarizing some recent morphological, biochemical and behavioural findings. It is suggested that cholecystokinin, acting via the cholecystokininB receptor, potentiates the glutamatergic excitatory input to the striatum. 相似文献
33.
Gilda J. Erosa-Rejón Alejandro Yam-Puc Manuel J. Chan-Bacab Alberto Giménez-Turbax Efraín Salamanca Luis M. Peña-Rodríguez Olov Sterner 《Phytochemistry letters》2010,3(1):9-12
Two new benzochromenes, (6,6-dimethyl-2-methoxy-6H-benzo[c]chromen-9-yl)methanol (1), and 2-methoxy-6,6-dimethyl-6H-benzo[c]chromen-9-carbaldehyde (2), together with several already known metabolites, were isolated from the root extract of Bourreria pulchra (Boraginaceae). The structures of 1 and 2 were established on the basis of their spectroscopic data. Both were assayed for in vitro antiprotozoan activity, and especially 1 was found to possess significant activity against Leishmania mexicana and Trypanosoma cruzi parasites (IC50 4.6 μg/mL and 7.5 μg/mL, respectively). 相似文献
34.
Sílvia Saumell Francesc Solé Leonor Arenillas Julia Montoro David Valcárcel Carme Pedro Carmen Sanzo Elisa Lu?o Teresa Giménez Montserrat Arnan Helena Pomares Raquel De Paz Beatriz Arrizabalaga Andrés Jerez Ana B. Martínez Judith Sánchez-Castro Juan D. Rodríguez-Gambarte José M. Raya Eduardo Ríos María Rodríguez-Rivera Blanca Espinet Lourdes Florensa 《PloS one》2015,10(6)
Isolated trisomy 8 is not considered presumptive evidence of myelodysplastic syndrome (MDS) in cases without minimal morphological criteria. One reason given is that trisomy 8 (+8) can be found as a constitutional mosaicism (cT8M). We tried to clarify the incidence of cT8M in myeloid neoplasms, specifically in MDS, and the diagnostic value of isolated +8 in MDS. Twenty-two MDS and 10 other myeloid neoplasms carrying +8 were studied. Trisomy 8 was determined in peripheral blood by conventional cytogenetics (CC) and on granulocytes, CD3+ lymphocytes and oral mucosa cells by fluorescence in situ hybridization (FISH). In peripheral blood CC, +8 was seen in 4/32 patients. By FISH, only one patient with chronic myelomonocytic leukemia showed +8 in all cell samples and was interpreted as a cT8M. In our series +8 was acquired in all MDS. Probably, once discarded cT8M by FISH from CD3+ lymphocytes and non-hematological cells, +8 should be considered with enough evidence to MDS. 相似文献
35.
Muñoz-Delgado E Montenegro MF Campoy FJ Moral-Naranjo MT Cabezas-Herrera J Kovacs G Vidal CJ 《The FEBS journal》2010,277(21):4519-4529
Despite the aberrant expression of cholinesterases in tumours, the question of their possible contribution to tumorigenesis remains unsolved. The identification in kidney of a cholinergic system has paved the way to functional studies, but details on renal cholinesterases are still lacking. To fill the gap and to determine whether cholinesterases are abnormally expressed in renal tumours, paired pieces of normal kidney and renal cell carcinomas (RCCs) were compared for cholinesterase activity and mRNA levels. In studies with papillary RCC (pRCC), conventional RCC, chromophobe RCC, and renal oncocytoma, acetylcholinesterase activity increased in pRCC (3.92 ± 3.01 mU·mg(-1), P = 0.031) and conventional RCC (2.64 ± 1.49 mU·mg(-1), P = 0.047) with respect to their controls (1.52 ± 0.92 and 1.57 ± 0.44 mU·mg(-1)). Butyrylcholinesterase activity increased in pRCC (5.12 ± 2.61 versus 2.73 ± 1.15 mU·mg(-1), P = 0.031). Glycosylphosphatidylinositol-linked acetylcholinesterase dimers and hydrophilic butyrylcholinesterase tetramers predominated in control and cancerous kidney. Acetylcholinesterase mRNAs with exons E1c and E1e, 3'-alternative T, H and R acetylcholinesterase mRNAs and butyrylcholinesterase mRNA were identified in kidney. The levels of acetylcholinesterase and butyrylcholinesterase mRNAs were nearly 1000-fold lower in human kidney than in colon. Whereas kidney and renal tumours showed comparable levels of acetylcholinesterase mRNA, the content of butyrylcholinesterase mRNA was increased 10-fold in pRCC. The presence of acetylcholinesterase and butyrylcholinesterase mRNAs in kidney supports their synthesis in the organ itself, and the prevalence of glycosylphosphatidylinositol-anchored acetylcholinesterase explains the splicing to acetylcholinesterase-H mRNA. The consequences of butyrylcholinesterase upregulation for pRCC growth are discussed. 相似文献
36.
37.
Jiménez Esperanza Piniella Dolores Giménez Cecilio Zafra Francisco 《Neurochemical research》2022,47(1):138-147
Neurochemical Research - The glycine transporter GLYT1 participates in inhibitory and excitatory neurotransmission by controlling the reuptake of this neuroactive substance from synapses. Over the... 相似文献
38.
39.
JI Priego AG Lucas-Cuevas I Aparicio JV Giménez JM Cortell-Tormo P Pérez-Soriano 《Biology of sport / Institute of Sport》2015,32(3):219-223
The use of graduated compression stockings (GCS) in sport has been increasing in the last years due to their potential positive effects for athletes. However, there is little evidence to support whether these types of garments actually improve cardiorespiratory performance. The aim of this study was to examine the cardiorespiratory responses of GCS during running after three weeks of regular use. Twenty recreational runners performed three tests on different days: test 1) – a 5-min maximal effort run in order to determine the participants’ maximal aerobic speed; and tests 2) and 3) – a fatigue running test of 30 minutes at 80% of their maximal aerobic speed with either GCS or PLACEBO stockings at random. Cardiorespiratory parameters (minute ventilation, heart rate, relative oxygen consumption, relative carbon dioxide production, ventilatory equivalents for oxygen and carbon dioxide, and oxygen pulse) were measured. Before each test in the laboratory, the participants trained with the randomly assigned stockings (GCS or PLACEBO) for three weeks. No significant differences between GCS and PLACEBO were found in any of the cardiorespiratory parameters. In conclusion, the present study provides evidence that running with GCS for three weeks does not influence cardiorespiratory parameters in recreational runners. 相似文献
40.
Ostrosky EA Marcondes EM Nishikawa Sde O Lopes PS Varca GH Pinto Tde J Consiglieri TV Baby AR Velasco MV Kaneko TM 《AAPS PharmSciTech》2011,12(2):732-737
Even though the synthetic preservatives may offer a high antimicrobial efficacy, they are commonly related to adverse reactions
and regarded as having potentially harmful effects caused by chronic consumption. The development of natural preservatives
provides a way of reducing the amount of synthetic preservatives normally used in pharmaceutical and cosmetic preparations.
In addition, these agents have less toxic effects and represent a possible natural and safer alternative of the preservatives.
The purpose of this research was to evaluate the Rubus rosaefolius Smith extract efficiency as a natural preservative in base formulations. Of the extract, 0.2% (w/w) was assayed for its effectiveness of antimicrobial protection in two different base formulations (emulsion and gel). The
microbial challenge test was performed following the standard procedures proposed by The United States Pharmacopoeia 33nd,
European Pharmacopoeia 6th, Japanese Pharmacopoeia 15th, and the Cosmetics, Toiletries, and Fragrance Association using standardized
microorganisms. The results demonstrated that R. rosaefolius extract at the studied concentration reduced the bacterial inocula, satisfying the criterion in all formulations, even though
it was not able to present an effective preservative behavior against fungi. Thus, the investigation of new natural substances
with preservative properties that could be applied in pharmaceutical and cosmetic products is relevant due to the possibility
of substituting or decreasing the concentration of synthetic preservatives, providing a way for the development of safer formulas
for the use of consumers. 相似文献