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91.
Heredia-Rojas JA Caballero-Hernandez DE Rodriguez-de la Fuente AO Ramos-Alfano G Rodriguez-Flores LE 《Bioelectromagnetics》2004,25(1):63-68
The effect of in vivo exposure of mice to a 60 Hz sinusoidal magnetic field (MF) at 2.0 mT on male germ cells was studied. The cytological endpoints measured included meiotic chromosome aberrations in spermatocytes and sperm morphology. Three independent experiments were carried out: (a) animals exposed for 72 h, (b) 10 days/8 h daily, and (c) 72 h exposure to MF plus 5 mg/kg of Mitomycin-C. No statistically significant differences indicative of MF effects were observed between MF exposed and control animals. In addition, an opposite effect between MF exposure and Mitomycin-C treatment in terms of chromosomal aberrations and sperm morphology was observed. 相似文献
92.
93.
HOTAIR role in melanoma progression and its identification in the blood of patients with advanced disease 下载免费PDF全文
94.
Marina Lozano Almudena Estalrrich Luca Bondioli Ivana Fiore José‐Maria Bermúdez de Castro Juan Luis Arsuaga Eudald Carbonell Antonio Rosas David W. Frayer 《Evolutionary anthropology》2017,26(6):313-324
Fossil hominids often processed material held between their upper and lower teeth. Pulling with one hand and cutting with the other, they occasionally left impact cut marks on the lip (labial) surface of their incisors and canines. From these actions, it possible to determine the dominant hand used. The frequency of these oblique striations in an array of fossil hominins documents the typically modern pattern of 9 right‐ to 1 left‐hander. This ratio among living Homo sapiens differs from that among chimpanzees and bonobos and more distant primate relatives. Together, all studies of living people affirm that dominant right‐handedness is a uniquely modern human trait. The same pattern extends deep into our past. Thus far, the majority of inferred right‐handed fossils come from Europe, but a single maxilla from a Homo habilis, OH‐65, shows a predominance of right oblique scratches, thus extending right‐handedness into the early Pleistocene of Africa. Other studies show right‐handedness in more recent African, Chinese, and Levantine fossils, but the sample compiled for non‐European fossil specimens remains small. Fossil specimens from Sima del los Huesos and a variety of European Neandertal sites are predominately right‐handed. We argue the 9:1 handedness ratio in Neandertals and the earlier inhabitants of Europe constitutes evidence for a modern pattern of handedness well before the appearance of modern Homo sapiens. 相似文献
95.
96.
Eduardo Massad Annelies Wilder-Smith Raphael Ximenes Marcos Amaku Luis Fernandez Lopez Francisco Antonio Bezerra Coutinho Giovanini Evelim Coelho Jarbas Barbosa da Silva Jr Claudio José Struchiner Marcelo Nascimento Burattini 《Memórias do Instituto Oswaldo Cruz》2014,109(3):394-397
Brazil will host the FIFA World Cup™, the biggest single-event competition in the
world, from June 12-July 13 2014 in 12 cities. This event will draw an estimated
600,000 international visitors. Brazil is endemic for dengue. Hence, attendees of the
2014 event are theoretically at risk for dengue. We calculated the risk of dengue
acquisition to non-immune international travellers to Brazil, depending on the
football match schedules, considering locations and dates of such matches for June
and July 2014. We estimated the average per-capita risk and expected
number of dengue cases for each host-city and each game schedule chosen based on
reported dengue cases to the Brazilian Ministry of Health for the period between
2010-2013. On the average, the expected number of cases among the 600,000 foreigner
tourists during the World Cup is 33, varying from 3-59. Such risk estimates will not
only benefit individual travellers for adequate pre-travel preparations, but also
provide valuable information for public health professionals and policy makers
worldwide. Furthermore, estimates of dengue cases in international travellers during
the World Cup can help to anticipate the theoretical risk for exportation of dengue
into currently non-infected areas. 相似文献
97.
Simone Guarnieri Caterina Morabito Silvia Belia Laura Barberi Antonio Musarò Giorgio Fanò-Illic Maria A. Mariggiò 《PloS one》2014,9(9)
Muscle regeneration involves the activation of satellite cells, is regulated at the genetic and epigenetic levels, and is strongly influenced by gene activation and environmental conditions. The aim of this study was to determine whether the overexpression of mIGF-1 can modify functional features of satellite cells during the differentiation process, particularly in relation to modifications of intracellular Ca2+ handling.Satellite cells were isolated from wild-type and MLC/mIGF-1 transgenic mice. The cells were differentiated in vitro, and morphological analyses, intracellular Ca2+ measurements, and ionic current recordings were performed.mIGF-1 overexpression accelerates satellite cell differentiation and promotes myotube hypertrophy. In addition, mIGF-1 overexpression-induced potentiation of myogenesis triggers both quantitative and qualitative changes to the control of intracellular Ca2+ handling. In particular, the differentiated MLC/mIGF-1 transgenic myotubes have reduced velocity and amplitude of intracellular Ca2+ increases after stimulation with caffeine, KCl and acetylcholine. This appears to be due, at least in part, to changes in the physico-chemical state of the sarcolemma (increased membrane lipid oxidation, increased output currents) and to increased expression of dihydropyridine voltage-operated Ca2+ channels. Interestingly, extracellular ATP and GTP evoke intracellular Ca2+ mobilization to greater extents in the MLC/mIGF-1 transgenic satellite cells, compared to the wild-type cells.These data suggest that these MLC/mIGF-1 transgenic satellite cells are more sensitive to trophic stimuli, which can potentiate the effects of mIGF-1 on the myogenic programme. 相似文献
98.
99.
Luigi Catacuzzeno Antonio Michelucci Luigi Sforna Francesco Aiello Miriam Sciaccaluga Bernard Fioretti Emilia Castigli Fabio Franciolini 《The Journal of membrane biology》2014,247(1):45-55
The swelling-activated chloride current (I Cl,Vol) is abundantly expressed in glioblastoma (GBM) cells, where it controls cell volume and invasive migration. The transduction pathway mediating I Cl,Vol activation in GBM cells is, however, poorly understood. By means of pharmacological and electrophysiological approaches, on GL-15 human GBM cells we found that I Cl,Vol activation by hypotonic swelling required the activity of a U73122-sensitive phospholipase C (PLC). I Cl,Vol activation could also be induced by the membrane-permeable diacylglycerol (DAG) analog OAG. In contrast, neither calcium (Ca2+) chelation by BAPTA-AM nor changes in PKC activity were able to affect I Cl,Vol activation by hypotonic swelling. We further found that R59022, an inhibitor of diacylglycerol kinase (DGK), reverted I Cl,Vol activation, suggesting the involvement of phosphatidic acid. In addition, I Cl,Vol activation required the activity of a EHT1864-sensitive Rac1 small GTPase and the resulting actin polymerization, as I Cl,Vol activation was prevented by cytochalasin B. We finally show that I Cl,Vol can be activated by the promigratory fetal calf serum in a PLC- and DGK-dependent manner. This observation is potentially relevant because blood serum can likely come in contact with glioblastoma cells in vivo as a result of the tumor-related partial breakdown of the blood–brain barrier. Given the relevance of I Cl,Vol in GBM cell volume regulation and invasiveness, the several key signaling molecules found in this study to be involved in the activation of the I Cl,Vol may represent potential therapeutic targets against this lethal cancer. 相似文献
100.
Cristina Llopis-Belenguer Juan Antonio Balbuena Iván Galván-Femenía Abril Rodríguez-González 《PloS one》2015,10(11)
Phenotypic variation results from the balance between sources of variation and counteracting regulatory mechanisms. Canalization and developmental stability are two such mechanisms, acting at two different levels of regulation. The issue of whether or not they act concurrently as a common developmental buffering capacity has been subject to debate. We used geometric morphometrics to quantify the mechanisms that guarantee phenotypic constancy in the haptoral anchors of Ligophorus cephali. Canalization and developmental stability were appraised by estimating inter- and intra-individual variation, respectively, in size and shape of dorsal and ventral anchors. The latter variation was estimated as fluctuating asymmetry (FA) between anchor pairs. The general-buffering-capacity hypothesis was tested by two different methods based on correlations and Principal Components Analyses of the different components of size and shape variation. Evidence for FA in the dorsal and ventral anchors in both shape and size was found. Our analyses supported the hypothesis of a general developmental buffering capacity. The evidence was more compelling for shape than for size and, particularly, for the ventral anchors than for the dorsal ones. These results are in line with previous studies of dactylogyrids suggesting that ventral anchors secure a firmer, more permanent attachment, whereas dorsal anchors are more mobile. Because fixation to the host is crucial for survival in ectoparasites, we suggest that homeostatic development of the ventral anchors has been promoted to ensure the morphological constancy required for efficient attachment. Geometric morphometrics can be readily applied to other host-monogenean models, affording not only to disentangle the effects of canalization and developmental stability, as shown herein, but to further partition the environmental and genetic components of the former. 相似文献