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《Gaceta sanitaria / S.E.S.P.A.S》2021,35(4):352-354
ObjectiveTo identify high-risk content in food advertising that combines obesogenic features with a highly emotionally engaging format.MethodComparison of 304 videos (47 hours and 41 minutes) from 13 food brand channels (traditional advertising) and from 15 child YouTuber channels (endorsement and influence) posted in 2019. Exploratory content analysis of variables describing the communication style of the “challenges” format.ResultsChallenges are the most common type of content (53.3%; n = 162), with a greater prevalence on child YouTuber channels (59%; n = 131) than on brand channels (41%; n = 31).ConclusionsContent created by consumers is not covered by current audiovisual communication legislation. Increased control of these practices is urgently needed, in terms of legislation, self-regulation and codes of ethics. Creativity, enjoyment or mere entertainment is not a sufficient argument for the persuasive promotion of behaviors that endanger the physical health of children. 相似文献
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F. Bonnel A. Dimeglio P. Baldet P. Rabischong 《Surgical and radiologic anatomy : SRA》1984,6(1):53-61
Summary The authors analyze at several levels the biomechanical activity of the epiphyseal plate.From a histologic point of view, they show the role played by the different cell layers in growth.The rapid growth of long bones is well known in animals, not entirely in human beings. The factors involved in mechanical regulation of the epiphyseal plate are analyzed according to distraction and compression stresses. Other factors have also been reported (periosteum and muscle).Analysis of the literature reveals that biomechanical activity and the factors managing growth are not well known yet.A combined effort should be made to obtain better understanding of the surgical procedures carried out in pediatric orthopedics.
Comportement biomécanique du cartilage de croissance. Incidences cliniques
Résumé Les auteurs analysent le comportement biomécanique du cartilage de croissance à plusieurs niveaux.Sur le plan histologique ils montrent le rôle joué dans la croissance par les différentes couches cellulaires.La vitesse de croissance des os longs est bien connue chez les animaux et difficile à apprécier chez l'homme. Les facteurs intervenant dans la régulation mécanique du cartilage sont analysés en fonction des contraintes en compression et en détraction. Les autres facteurs (périoste et muscle) sont rapportés.L'analyse de la littérature montre combien le comportement mécanique et les facteurs régissant la croissance sont mal connus et mériteraient un effort de recherche conjugué pour mieux comprendre la portée des gestes chirurgicaux en orthopédie infantile.相似文献
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Elizabeth Knyihár-Csillik Ágotha Török Bert Csillik 《The Journal of comparative neurology》1990,297(4):594-612
Substance P-like immunoreactivity (SPLI) was localized in the superficial spinal dorsal horn of the rat by means of light and electron microscopic immunocytochemical techniques. Serial immunocytochemical sections were subjected to densitometric measurements with an electronic Image Analyser, and with aid of a computer program, a two-dimensional reconstruction of the fine neuroanatomical structure of the SPLI-active regions of the lumbosacral upper superficial spinal dorsal horn was obtained. SPLI activity in the superficial dorsal horn outlines four well-marked and distinctly differing regions, called, in the mediolateral sequence, areas A, B, C, and D, plus Cajal's noyeau interstitiel ("lateral spinal nucleus" = "nucleus of the dorsolateral fascicle," L). Lumbosacral dorsal rhizotomy results in an almost complete depletion of SPLI from ipsilateral areas A, B, C, and D; it induces decreased SPLI in the area of the lateral spinal nucleus (L), ipsi- or contralaterally in an alternating fashion. Transection of the segmentally related, ipsilateral peripheral nerve induces a marked depletion of SPLI from areas A, B, and C but only a slight decrease in area D and virtually none in the area of L. Whereas a simple crush of the peripheral nerve (axocompression) induces only a slight depletion of SPLI, if any, semiautomatic densitometric analysis of serial immunocytochemical sections proves that a controlled crush injury (axocontusion) results in depletion of SPLI from the upper dorsal horn, similar to transection of the peripheral nerve. Following regeneration of the ipsilateral, segmentally related peripheral nerve, the original immunocytochemical structure of the superficial dorsal horn is re-established by SPLI-positive axonal sprouts originating from previously damaged dorsal root axons. 相似文献
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Oncogene SET Domain Bifurcated 1 (SETDB1)/ESET, an H3K9 methyltransferase, was originally discovered over two decades ago; however, its function in the immune response was not first reported until 2011. SETDB1 immune functions include B cell maturation, T cell activity regulation, and immune escape in cancer cells. In B lymphocytes, SETDB1 mediates the transition from pro-B to pre-B cells and represses endogenous retroviruses (ERV) to encourage B cell lineage differentiation and maturation. SETDB1 alters T cell function by methylating IL-2 and IL-17 promoters and mediating T cell lineage commitment and development. In addition, SETDB1 plays a critical role in ERV silencing within a variety of immune cells, which can indirectly weaken the immune response. Although SETDB1 is critical for normal immune cell function, overexpression in cancer cells negatively impacts immune cell fights against cancer through decreased tumour immunogenicity. Within cancer cells, SETDB1 overexpression represses production and infiltration of antitumour immune cells, mediates immune escape through TE and ERV silencing, represses the type I interferon pathway, and interferes in immune checkpoint blockade (ICB) outcomes by regulation of PD-L1 expression and IFN signalling. In this review, we further discuss the immunological mechanisms of SETDB1 in normal and cancerous cells and its implications in cancer immunotherapy. 相似文献
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Omoto M Imai T Seki K Nomura R Otahara Y 《Environmental health and preventive medicine》1997,2(3):105-116
Based on the fact that chemical products such as binding agents are produced by mixing three kinds of phosphates with different
ratios, we mixed metaphosphate, polyphosphate and pyrophosphate. Each was made to Na-phosphate, K-phosphate, and Ca-phosphate
and each was mixed with commercial feeds so that the content of P would be approximately 0.1, 0.15, 0.3, 0.4, 0.6 and 1.0%.
The prepared pellets were given to ICR, CF # 1 and AKR strains of mice at 29 days of age for 680 days and observations were
made through this experimental period at different stages. The observations were also carried out on the mice administered
with the experimental feeds for 1.5 months from 9 to 10.5 months of age. The observations were compared with those of the
control group at all times. As a result, plasma 1 α, 25 (OH)2 D3 and P levels were always significantly higher in the phosphate administered groups relative to the control. Urine P and Fe
increased while urine Ca decreased in the phosphate-treated groups.
The effect of phosphates on the bones was studied taking soft X-ray pictures of hind legs and applying microdensitometry to
them. Through these observations we recognized thinning of the cortex of bones, reduction of marrow trabecules and development
of osteophyte. Histological observations disclosed that changes in knee joint tissues were apparent; that is, a decrease in
or an irregular loss of the number of cells in superficial, intermediate, and radial strata of the joint cartilage, proliferation
of subchondral bone, and the development of osteophytes were noted. As for muscles, diameters of musclar fibers became smaller;
in particular, type II fibers showed greater shrinkage. Regarding kidneys, swelling and atrophy of glomerular capillaries,
proliferation of mesangial cells, nephroselerosis, swelling, thinning, and loss of tubular epithelium, interstitial tissue
inflammation, development of cylindruria, and deposition of calcium were observed. All these changes seem to be a particularly
advanced aspect of the changes which are more pronounced with increasing dose and age.
These changes were found even in the group administered with the feed containing 0.1% phosphorus, and, these changes were
dependent on the concentration level of P. It was observed that administration to older subjects for a short term (1.5 months)
produced effects stronger than those to younger subjects administered for a long term (10.5 months).
The effects of condensed Ca-phosphate on bones were similar to those of condensed Na- and K-phosphates, and, hence, it was
supposed that these effects were caused by phosphate radicals.
An erratum to this article is available at . 相似文献
100.