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71.
Isakson BE Best AK Duling BR 《American journal of physiology. Heart and circulatory physiology》2008,294(6):H2898-H2904
Although much physiology in resistance vessels has been attributed to the cytoplasmic connection between endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), little is known of the protein expression between the two cell types. In an attempt to identify the proteins between ECs and VSMCs, mouse cremaster arterioles were stained with phalloidin-Alexa 594 and viewed on a confocal microscope that resolved "actin bridges" within the internal elastic lamina between ECs and VSMCs. To determine the incidence of protein, the pixel intensity from the antibodies on actin bridges were compared with the pixel intensity from antibodies within ECs or VSMCs. N-cadherin, desmin, connexin (Cx)40, and Cx43 and phosphorylated Cx43 at serine-368 were identified on actin bridges, but NG2, CD31, and Cx45 were not evident. Cx37 expression was more variable than the other connexins examined. Using this method on rat mesentery, we confirm the previously published predominance of Cx37 and Cx40 at the myoendothelial junction that was determined using electron microscopy. We conclude that this new method represents an important screening mechanism in which to rapidly test for protein expression between ECs and VSMCs and possibly a first-step in quantifying protein expression at the myoendothelial junction. 相似文献
72.
Pentzos Daponte A. Vienna A. Brant L. Hauser G. 《International Journal of Anthropology》2004,19(4):289-295
In 14141 male and 14141 female Greek children and adolescents ranging in age between seven and fifteen years the presence
of cheek dimples was investigated. Neither sex (12.6% in both female and males) nor side differences when expressed unilaterally
were observed. There was however a significant increase of dimples with age as well as significantly higher numbers of asymmetric
than symmetric expressions in all age groups.
With respect to these observations hypotheses of origin of cheek dimples and related effects of age are discussed. 相似文献
73.
The biomass, production and mortality of fine roots (roots with diameter <2.5 mm) were studied in a typical Mediterranean holm oak (Quercus ilex L.) forest in NE Spain using the minirhizotron methodology. A total of 1212 roots were monitored between June of 1994 and March of 1997. Mean annual fine root biomass in the holm oak forest of Prades was 71±8 g m–2 yr–1. Mean annual production for the period analysed was 260+11 g m–2 yr–1. Mortality was similar to production, with a mean value of 253±3 g m–2 yr–1. Seasonal fine root biomass presented a cyclic behaviour, with higher values in autumn and winter and lower in spring and summer. Production was highest in winter, and mortality in spring. In summer, production and mortality values were the lowest for the year. Production values in autumn and spring were very similar. The vertical distribution of fine root biomass decreased with increasing depth except for the top 10–20 cm, where values were lower than immediately below. Production and mortality values were similar between 10 and 50 cm depth. In the 0–10 cm and the 50–60 cm depth intervals, both production and mortality were lower. 相似文献
74.
Lora Sigmon Sarah Hoopes Morgan Booker Catherine Waters Kara Salpeter Brant Touchette 《Wetlands Ecology and Management》2013,21(1):45-54
Bioretention basins are man-made topographic depressions designed to collect and retain surface water runoff. In most cases these basins are used to prevent flooding and/or remove environmentally harmful pollutants and sediments from entering natural aquatic systems. To maximize environmental benefits, these systems are often planted with flood-tolerant wetland hydrophytes that are capable of withstanding extended periods of drought. Unfortunately, little is known about how these plants respond to extreme hydrologies while breaking seasonal dormancy. The purpose of this study was to better understand the morphological and physiological responses of three wetland species (Pontederia cordata L., Saururus cernuus L., and Schoenoplectus tabernaemontani C.C. Gmel. Palla) often used in bioretention basins while emerging from dormancy in either flooded or drought conditions. Results indicate that only S. tabernaemontani was affected morphologically by drought with lower leaf area and aboveground biomass. While significant reductions in stomatal surface indices were also observed in drought-treated S. tabernaemontani, all three species had reductions in stomatal conductance (g) when grown in drier soils. Moreover, drought conditions promoted decreases in leaf water potential (Ψ leaf) for all three species, and reductions in tissue water content (θ) for P. cordata and S. tabernaemontani. Based on the overall morphological and physiological responses, S. cernuus maintained the lowest productivity, and appeared to be the best suited for tolerating sustained soil water deficits. If high plant productivity is desired, however, S. tabernaemontani was able to maintain high plant growth while making necessary modifications that facilitated greater drought-resistance. 相似文献
75.
Gillian C. L. Lachelin H. A. Brant G. I. M. Swyer V. Little E. O. R. Reynolds 《BMJ (Clinical research ed.)》1972,1(5803):787-790
In a sextuplet pregnancy which followed gonadotrophin therapy the principal problems were threatened abortion, premature labour, and placental insufficiency. Delivery was by caesarean section soon after the onset of labour at 32 weeks. The five liveborn babies thrived. The sixth was a macerated stillbirth. 相似文献
76.
Clare Brant 《Ethnos》2013,78(4):544-563
Olfactory studies are truly multidisciplinary, from anthropology to zoology. What literary criticism can offer is analysis of the language of smell and the discourses of olfactory practice which give smell meanings. In this paper I explore the poetics of odour in selected contexts in the developed West of the twenty-first century. I argue that the language of smell is elusive, contradictory, disguised: nonetheless, it deploys metaphor, story, personal meaning and social meaning, all frames that ‘nest’ together. I demonstrate contradictions of olfactory practice with reference to urban space and technologies of scent, acting on bodies and places. I argue that a relationship between scent, identity and space can be understood in terms of an olfactory sublime, to which there is also resistance, sanctioned by new laws. In public space, the complexity of deodorisation appears in the conflict between fragrance-free and compulsory olfaction, as I argue with reference to Halifax, Nova Scotia and to the London Underground. 相似文献
77.
78.
Joan Francesc Mir Sebastián Zagmutt Mathieu P Lichtenstein Judit García-Villoria Minéia Weber Ana Gracia Gemma Fabriàs Josefina Casas Miguel López Núria Casals Antònia Ribes Cristina Suñol Laura Herrero Dolors Serra 《Molecular neurobiology》2018,55(9):7216-7228
Lipid metabolism, specifically fatty acid oxidation (FAO) mediated by carnitine palmitoyltransferase (CPT) 1A, has been described to be an important actor of ghrelin action in hypothalamus. However, it is not known whether CPT1A and FAO mediate the effect of ghrelin on the cortex. Here, we show that ghrelin produces a differential effect on CPT1 activity and γ-aminobutyric acid (GABA) metabolism in the hypothalamus and cortex of mice. In the hypothalamus, ghrelin enhances CPT1A activity while GABA transaminase (GABAT) activity, a key enzyme in GABA shunt metabolism, is unaltered. However, in cortex CPT1A activity and GABAT activity are reduced after ghrelin treatment. Furthermore, in primary cortical neurons, ghrelin reduces GABA release through a CPT1A reduction. By using CPT1A floxed mice, we have observed that genetic ablation of CPT1A recapitulates the effect of ghrelin on GABA release in cortical neurons, inducing reductions in mitochondrial oxygen consumption, cell content of citrate and α-ketoglutarate, and GABA shunt enzyme activity. Taken together, these observations indicate that ghrelin-induced changes in CPT1A activity modulate mitochondrial function, yielding changes in GABA metabolism. This evidence suggests that the action of ghrelin on GABA release is region specific within the brain, providing a basis for differential effects of ghrelin in the central nervous system. 相似文献
79.
80.
J L Arsuaga I Martínez C Lorenzo A Gracia A Mu?oz O Alonso J Gallego 《Journal of human evolution》1999,37(3-4):431-457
In this article we study the cranial remains of the late Lower Pleistocene human fossils from Gran Dolina (Sierra de Atapuerca, Spain), assigned to the new species Homo antecessor. The cranial remains belong to at least five individuals, both juveniles and adults. The most outstanding feature is the totally modern human morphology of the very complete face ATD6-69, representing the earliest occurrence of the modern face in the fossil record. The Gran Dolina fossils show in the face a suite of modern human apomorphies not found in earlier hominids nor in contemporary or earlier Homo erectus fossils. There are also traits in the Gran Dolina fossils shared with both Neandertals and modern humans, which reinforce the hypothesis that Neandertals and modern humans form a clade, and that the Gran Dolina fossils are a common ancestor to both lineages. 相似文献