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991.
《Bioscience, biotechnology, and biochemistry》2013,77(6):1171-1178
This study sought to encapsulate a high concentration of L-ascorbic acid, up to 30% (w/v), in the inner aqueous phase of water-in-oil-water (W/O/W) emulsions with soybean oil as the oil phase. Two-step homogenization was conducted to prepare W/O/W emulsions stabilized by a hydrophobic emulsifier and 30% (v/v) of W/O droplets stabilized by a hydrophilic emulsifier. First-step homogenization prepared W/O emulsions with an average aqueous droplet diameter of 2.0 to 3.0 μm. Second-step homogenization prepared W/O/W emulsions with an average W/O droplet diameter of 14 to 18 μm and coefficients of variation (CVs) of 18% to 25%. The results indicated that stable W/O/W emulsions containing a high concentration of L-ascorbic acid were obtained by adding gelatin and magnesium sulfate in the inner aqueous phase and glucose in both aqueous phases. L-Ascorbic acid retention in the W/O/W emulsions was 40% on day 30 and followed first-order kinetics. 相似文献
992.
S. El Issami M.A. Bsiss A. Matrane S. Hiroual S. Bennani Doubli N. Ben Raïs Aouad 《Médecine Nucléaire》2013,37(10-11):520-525
The presence of a parathyroid gland in ectopic position constitutes one of the leading causes of surgery failure. For this purpose, scintigraphy takes a major place in the anatomical localization of pathological parathyroid and so facilitates its treatment. The advent of hybrid cameras combining single photon emission tomography to CT (SPECT/CT) has further strengthened the contribution of this imaging modality in the precise localization of ectopic parathyroid and its anatomical relationships. The objective of our work is to illustrate the interest of hybrid imaging SPECT/CT, compared to planar scintigraphy and ultrasounds within the framework of primary hyperparathyroidism, particularly ectopic situation through three cases. 相似文献
993.
S. Yossi J. Sayegh P. Fosse A. Pajot J.-Y. Tanguy J.-F. Augusto 《Médecine Nucléaire》2013,37(9):397-400
Odontoid process is an atypical and very rare localization of osteomyelitis. We reported the case of a 72-year-old hemodialysed man with methicillin-sensitive Staphylococcus aureus osteomyelitis of the odontoid process. Osteomyelitis was diagnosed at MRI and 18F-FDG PET/CT. While clinical examination and conventional radiographs were non contributive, 18F-FDG PET/CT also allowed the diagnosis of right foot osteomylitis and multiple vertebral septic localizations. 18F-FDG PET/CT done at month 3 demonstrated a regression of the odontoid and foot hypermetabolic activity. This case illustrates the atypical presentation of this septic localization and the usefulness of 18F-FDG PET/CT to perform whole body screening and detect septic metastasis. 相似文献
994.
Retinoic acid (RA) contributes to cleft palate; however, the cellular and molecular mechanisms responsible for the deleterious effects on the developing palate are unclear. Wnt signaling is a candidate pathway in the cleft palate and is associated with RA in organ development; thus, we aim to investigate whether RA-induced cleft palate also results from altered Wnt signaling. Administration of RA to mice altered cell proliferation and apoptosis in craniofacial tissues by regulating molecules controlling cell cycle and p38 MAPK signaling, respectively. This altered cell fate by RA is a crucial mechanism contributing to 100% incidence of cleft palate. Moreover, Wnt/β-catenin signaling was completely inhibited by RA in the early developing palate via its binding and activation with RA receptor (RAR) and is responsible for RA-induced cleft palate. Furthermore, PI3K/Akt signaling was also involved in actions of RA. Our findings help in elucidating the mechanisms of RA-induced cleft palate. 相似文献
995.
Y Liu H Cheng Y Zhou Y Zhu R Bian Y Chen C Li Q Ma Q Zheng Y Zhang H Jin X Wang Q Chen D Zhu 《Cell death & disease》2013,4(2):e494
Myostatin, a member of the transforming growth factor-β superfamily, regulates the glucose metabolism of muscle cells, while dysregulated myostatin activity is associated with a number of metabolic disorders, including muscle cachexia, obesity and type II diabetes. We observed that myostatin induced significant mitochondrial metabolic alterations and prolonged exposure of myostatin induced mitochondria-dependent apoptosis in cancer cells addicted to glycolysis. To address the underlying mechanism, we found that the protein levels of Hexokinase II (HKII) and voltage-dependent anion channel 1 (VDAC1), two key regulators of glucose metabolisms as well as metabolic stress-induced apoptosis, were negatively correlated. In particular, VDAC1 was dramatically upregulated in cells that are sensitive to myostatin treatment whereas HKII was downregulated and dissociated from mitochondria. Myostatin promoted the translocation of Bax from cytosol to mitochondria, and knockdown of VDAC1 inhibited myostatin-induced Bax translocation and apoptosis. These apoptotic changes can be partially rescued by repletion of ATP, or by ectopic expression of HKII, suggesting that perturbation of mitochondrial metabolism is causally linked with subsequent apoptosis. Our findings reveal novel function of myostatin in regulating mitochondrial metabolism and apoptosis in cancer cells. 相似文献
996.
The regional specialization of brain function has been well documented in the mouse and fruitfly. The expression of regulatory factors in specific regions of the brain during development suggests that they function to establish or maintain this specialization. Here, we focus on two such factors—the Drosophila cephalic gap genes empty spiracles (ems) and orthodenticle (otd), and their vertebrate homologues Emx1/2 and Otx1/2—and review novel insight into their multiple crucial roles in the formation of complex sensory systems. While the early requirement of these genes in specification of the neuroectoderm has been discussed previously, here we consider more recent studies that elucidate the later functions of these genes in sensory system formation in vertebrates and invertebrates. These new studies show that the ems and Emx genes in both flies and mice are essential for the development of the peripheral and central neurons of their respective olfactory systems. Moreover, they demonstrate that the otd and Otx genes in both flies and mice are essential for the development of the peripheral and central neurons of their respective visual systems. Based on these recent experimental findings, we discuss the possibility that the olfactory and visual systems of flies and mice share a common evolutionary origin, in that the conserved visual and olfactory circuit elements derive from conserved domains of otd/Otx and ems/Emx action in the urbilaterian ancestor. 相似文献
997.
998.
《Archives of animal nutrition》2013,67(3):243-259
In order to study the main effects of particle size, three ruminally fistulated cows (550 to 580 kg BW) were fed a constant low concentrate level (3.56 kg DM/d, 20% of total DMI) and a fibre‐rich hay (approximately 60% NDF in DM) in long (28.7 mm), chopped (9.2 mm) and fine ground (2.9 mm) form in a 3 x 3 Latin square design. In another three factorial experiment with 8 wethers (4 animals were ruminally fistulated, mean BW = 68 kg) the main effects and interactions of the above mentioned hay particle sizes at two concentrate levels (10.4 to 13.3% and 29.5 to 40.1% of DMI, resp.) and two intake levels (restricted and ad libitum) were investigated. In comparison to long hay (28.7 mm), feeding of chopped hay (9.2 mm) at low concentrate levels, increased not only the hay intake (7% in dairy cows and 13% in sheep) but also the intake of digestible organic matter (12% in dairy cows and 32% in sheep), due to an increase in the apparent digestibility of OM by 3.8% in dairy cows and 8.2% in sheep. Ad libitum feeding of fine ground hay in combination with low concentrate amount in the ration increased the passage rate in the hindgut and consequently the hay intake, but not the intake of DOM, due to a significant depression of digestibility, especially of fibre fractions (4 to 7% in dairy cows and 4.5 to 14% in sheep), in comparison to 28.7 and 9.2 mm hay particle sizes. The digestibility decreased significantly with restricted feeding of fine ground hay in sheep only in comparison to 9.2 mm particle size. A threefold increase of concentrate amount levelled out all effects of the particle size reduction. The effect of particle size was more pronounced in sheep than in dairy cows. 相似文献
999.
Some experts suggest that sedation of laboratory rodents with isoflurane before euthanasia with carbon dioxide (CO2) is a humane alternative to euthanasia with CO2 alone, but little research has compared aversion with these agents. Albino rats were tested in a light–dark box where they had the choice between remaining in a dark compartment filling with isoflurane or CO2, or escaping to a lit compartment. Experiment 1 validated the procedure by confirming that rats responded to agent and light intensity. In experiment 2, 9/16 and 0/16 rats remained in the dark compartment until recumbent when initially exposed to isoflurane and CO2, respectively. In experiment 3, more rats remained in the dark compartment until recumbent during initial (10/16) versus re-exposure (1/16) to isoflurane. These results indicate that initial exposure to CO2 is more aversive than isoflurane, and that re-exposure to isoflurane is more aversive than initial exposure. We conclude that sedation with isoflurane is a refinement over euthanasia with CO2 alone for rats that have not been previously exposed to inhalant anaesthetics. 相似文献
1000.
A.D. Bradshaw 《Plant Ecology & Diversity》2013,6(4):303-311
Summary In the light of all that has been discovered about the mechanism of evolution it has become tempting to follow Darwin's lead and to “see no limit to this power“. Yet a careful examination of situations in which evolution is known to be occurring in some species, shows complete absence of evolution in others. This not because these species have not had the opportunity; in many situations there may even be uncolonised bare space. The explanation must lie in the supply of appropriate variation. A tacit assumption of evolution by natural selection is that the necessary variation is always available. Yet there is no a priori justification for this. Evidence from populations in nature, particularly of species which are potential colonists of old metal mine workings and similar metal contaminated habitats, shows that the species that successfully colonise these habitats, by the evolution of metal tolerant populations, possess within their normal populations the necessary variation. But those species which fail to colonise these habitats, despite the opportunity, do not possess this variation. This applies also at the level of the population, in the replicated evolutionary situations occurring under electricity pylons. Such evidence, together with arguments from theory, suggests that the failures of evolution have been as important as its successes in moulding the living world as we see it today, and that the reasons for failure must be sought at the molecular level in limitations to the origin of new variation. 相似文献