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21.
Examined how environmental and physical characteristics contribute to the emergence of adolescent girls' dating behavior. The premise was that one set of individual characteristics, pubertal processes, may have more influence on girls' dating behavior in one context than in another, specifically more in girls who attend dance schools than in those who do not. Seventh to ninth grade girls were seen, 59 who were enrolled in national classical ballet company school and 328 who were not. Body image, dating behavior, career aspirations, pubertal status, and maturational timing were assessed via self-report and maternal report. Dancers were less likely to date than nondancers. A Dance/Nondance Group?×?Pubertal Status interaction was found: Premenarcheal dancers had lower dating scores than postmenarcheal dancers, whereas menarcheal status was not related to dating in nondancers. With regard to body image, a Breast Development?×?Dance/Nondance Group interaction was found, with breast development being negatively related to body image in dancers and unrelated in nondancers. Findings are discussed in terms of interactions between environmental and physical characteristics and the goodness of fit between contextual demands and a girl's particular physical characteristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
22.
The ion-exchange properties of a synthetic hydrosodalite (Na-hS) have been investigated by kinetic and thermodynamic analysis of exchange reactions of the original sodium form for lithium, potassium and calcium forms. Kinetic curves, modelled by a Langmuir-type equation, revealed that exchange rate for lithium and for potassium are of the same order, whereas they are two order faster than for calcium. Thermodynamic analysis of the cation exchange isotherms pointed out that sodalite is selective for sodium over the other three cationic forms examined, which is consistent with the preference exhibited by the sodalite type for sodium environments, either in natural or in laboratory crystallization. Na/Li and Na/Ca exchanges are incomplete, whereas unexpectedly Na/K exchange turns out to be complete, even though K+ dimension exceeds the width of the access window to sodalite cages. The obtained results have been discussed in terms of Eisenman–Sherry theory, pointing out agreements and discrepancies.  相似文献   
23.
Metal-organic framework (MOF) incorporating conductive graphene-like layers were synthesized and characterized. The selected MOF, HKUST-1, combines high surface area, water stability, simple preparation and low costs. Graphene-like layers incorporated into the MOF structure were obtained by a two-step oxidation/reduction wet treatment of a high surface carbon black. MOF composites were produced at different carbonaceous layers content. It was shown, through a wide characterization of the samples, that the composites preserve the main features of the parent MOF, additional exhibiting a tunable electrical conductivity.  相似文献   
24.
25.
Clinical and diagnostic findings of Paget's disease of the jaws are reported; up to date etiological and pathogenical hypotheses are presented. Laboratory data of increased P.A. as a marker of disease evolution is pointed out, particularly the relationship increasing hydroxyprolinuria, because the increase of a malignant transformation. Surgery, always modeling, is limited to cases of severe facial dysmorphosis associated or not with the local disturbance due to compression; in any case it is suggested to perform the surgery in the phases of inactivity of disease, to avoid local complications, such as hemorrhage a infection.  相似文献   
26.
The occurrence and localization of neurotrophins and their specific TrK receptor-like proteins in the adrenal gland of chicken, duck and ostrich were examined by immunohistochemical methods. In all species studied NGF-, TrK A- and TrK C-like immunoreactivity was observed in neurons and fibers of adrenal ganglia. Thin TrK A- and TrK C-like immunoreactive fibers were also observed among chromaffin cells. NT-3-like immunoreactivity was detected in chromaffin cells as revealed by the double immunolabelings NT-3/chromogranin A and NT-3/DbetaH. The interrenal tissue never showed IR to any neurotrophins and TrK tested, and none of the adrenal structures displayed immunoreactivity to BDNF and TrK B. Double immunolabelings NGF/TrK A, NGF/TrK C and TrK A/TrK C showed colocalization in some neurons and fibers in adrenal ganglia. In adrenal glands of the species studied, the distribution of neurotrophins and TrK receptors could suggest an involvement of NT-3 on neuronal populations innervating adrenal ganglia by means of its high affinity receptor TrK C and low affinity receptor TrK A. In addition, NGF could be utilized by neuronal populations of adrenal ganglia through its preferential receptor TrK A by an autocrine or paracrine modality of action.  相似文献   
27.
Multiple‐cycle breakthrough tests of a binary gas mixture of the halogenated anesthetic sevoflurane (SF) and water vapor were performed on both the synthesized chromium‐based metal organic framework (Cr‐MOF) and a conventionally used reference adsorbent. At 1 vol % SF and 50 % relative humidity mixture composition, the Cr‐MOF (MIL‐101) showed a significantly higher SF adsorption capacity, lower water vapor adsorption capacity, and no roll‐up effect compared to the reference sample. After each adsorption measurement, the saturated column was regenerated. MIL‐101 showed higher stability with minor SF capacity loss after 14 cycles, while the reference sample lost about a half of the SF capacity after 17 cycles.  相似文献   
28.
Leptin is a modulator of food intake and energy homeostasis both in mammals and in some species of nonmammals vertebrates. In this study, we reported for the first time, using an immunohistochemical and immunochemical approach, the presence and distribution of immunoreactivity to leptin-like protein in the gastroenteric tract of Dicentrarchus labrax (bass) and Carassius auratus (goldfish), two teleostean species with different feeding and different adaptative morphological organization of the gastroenteric tract. Bass stomach showed intense immunoreactivity to leptin-like protein in all regions, with immunoreactive cells located at the base of the mucosal plicae and at the apical margin of the gastric crypts. Immunoreactive fibers and neuronal cells were observed close to vascular structures in the pyloric region. In bass and goldfish intestine, rare immunoreactive cells were observed along the mucosal epithelium mostly at the base or the apex of intestinal folds in the proximal and medium intestine; numerous immunoreactive nerve fibers in the circular and longitudinal layers of the tunica muscolaris as well as in the myenteric plexus were observed. Western blot analysis recognized a ~15 kDa signal with a similar expression pattern for goldfish and sea bass. Our results could contribute to confirm the evolutive conservation of leptin-like proteins and their probably precocious functional diversification in fish.  相似文献   
29.
The aim of the present work is the study of the bacteriostatic/bactericidal effect of a silver-containing mesoporous bioactive glass obtained by evaporation-induced self-assembly and successive thermal stabilization. Samples of the manufactured mesophase were characterized by means of transmission electron microscopy and N2 adsorption/desorption at 77 K, revealing structural and textural properties similar to SBA-15 mesoporous silica. Glass samples used for bioactivity experiments were put in contact with a standardized, commercially available cell culture medium instead of lab-produced simulated body fluid, and were then characterized by means of X-ray diffraction, field emission scanning electron microscopy and Fourier transform infrared spectroscopy. All these analyses confirmed the development of a hydroxyl carbonate apatite layer on glass particles. Moreover, the investigated mesostructure showed a very good antibacterial effect against S. aureus strain, with a strong evidence of bactericidal activity already registered at 0.5 mg/mL of glass concentration. A hypothesis about the mechanism by which Ag affects the bacterial viability, based on the intermediate formation of crystalline AgCl, was also taken into account. With respect to what already reported in the literature, these findings claim a deeper insight into the possible use of silver-containing bioactive glasses as multifunctional ceramic coatings for orthopedic devices.  相似文献   
30.
The hypercholesterolemia-atherosclerosis association is now established; hypercholesterolemia may induce vascular-cell activation, subsequently increasing expression of adhesion molecules, cytokines, chemokines, growth factors, and other key inflammatory molecules. Among inflammatory molecules expressed by vascular cells, integrins play a critical role in regulating macrophage activation and migration to the site of inflammation, by mediating cell-cell and cell-extracellular matrix interactions. The main lipid oxidation products present in oxidized LDL that may be responsible for inflammatory processes in atherogenesis, are cholesterol oxidation products, known as oxysterols. This study demonstrates the effect of an oxysterol mixture, compatible with that detectable in human hypercholesterolemic plasma, on the expression and synthesis of β1-integrin in cells of the macrophage lineage. The molecular signaling whereby oxysterols induce β1-integrin up-regulation is also comprehensively investigated. Over-expression of β1-integrin depends on activation of classic and novel members of protein kinase C and extracellular signal-regulated kinases 1 and 2, as well as of the up-stream G-protein (Gq and G13), c-Src, and phospholipase C. In addition, the localization of β1-integrin in advanced human carotid plaques is highlighted, marking its importance in atherosclerotic plaque progression.  相似文献   
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