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21.
We report a novel structural and magnetic investigation of carbon foam (CFM) materials filled with SmFeO3 crystals produced by (1) high temperature fusion between Sm2O3- and Fe3C-filled carbon onions and (2) annealing of iron filled CFM with nanosized Sm2O3. Presence of a defect-rich monolayer-like CFM arrangement characterized by sharp interfaces with a SmFeO3 single-crystal phase is demonstrated through TEM and HRTEM. Further, the presence of intense sp3-rich features with variable carbonate content is evidenced by XPS and Raman spectroscopy. Complementary VSM, SQUID and ESR show also presence of intrinsic magnetization features which appeared to be attributable to the interfacial vacancy-rich regions of the graphitic CFM layers, as confirmed by Raman spectroscopy. Together with these signals, possible ferromagnetic contributions from the SmFeO3 phase and α-Fe impurities are reported. These observations highlight therefore the presence of switchable interfacial magnetization features at the carbon/SmFeO3 interface due to the variable concentrations of vacancies at the CFM interface, opening new directions towards applications in magnetic and interfacial-driven ferroelectric devices.

We report a novel structural and magnetic investigation of carbon foam (CFM) filled with SmFeO3 crystals produced by (1) high temperature fusion between Sm2O3 and Fe3C-filled carbon onions, and (2) annealing of iron filled CFM with nanosized Sm2O3.  相似文献   
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The National Center on Birth Defects and Developmental Disabilities at the Centers for Disease Control and Prevention conducted a workshop in January 2006, entitled "Prioritizing a Research Agenda for Orofacial Clefts." The goals of the meeting were to review existing research on orofacial clefts (OFCs), identify gaps in knowledge that need additional public health research, and develop a prioritized research agenda that can help guide future public health research. Experts in the field of epidemiology, public health, genetics, psychology, speech pathology, dentistry, and health economics participated to create the research agenda. Research gaps identified by the participants for additional public health research included: the roles of maternal nutrition, obesity, and diabetes in the etiology of OFCs; psychosocial outcomes for children with OFCs; the quality of life for families and children with OFCs; and the health care costs of OFCs. To create the research agenda, the participants prioritized the research gaps by public health importance, feasibility, and outcomes of interest. This report summarizes the workshop.  相似文献   
24.

Background

Colitis, a colonic inflammatory condition, showed a linkage with hepatobiliary disorders such as cirrhosis. It has been reported that both endogenous opioids and nitric oxide (NO) play critical roles in colitis pathogenesis. Moreover, opioid and NO levels showed elevation in patients with cirrhosis. The aim of this study was to evaluate the effect of cirrhosis on the experimental model of colitis and the possible involvement of opioidergic/nitrergic systems in rats.

Methods

Colitis was induced by acetic acid 28 days after bile duct ligation (BDL). L-NAME, as an inhibitor of NO synthase and naltrexone, as an antagonist of opioid receptors were administered intraperitoneally to animals during 3 days after induction of colitis. Macroscopic colitis lesion area, inflammatory mediators change, NO metabolite levels, and colon microscopic injuries were assessed 3 days after induction.

Results

Cirrhosis significantly reduced the severity of damages to the colon. Administration of L-NAME (10 mg/kg), naltrexone (10 mg/kg) and co-administration of L-NAME (1 mg/kg) and naltrexone (5 mg/kg) significantly decreased the protective effect of BDL on colitis. Nitrite elevated levels in BDL rats were significantly diminished in L-NAME- and naltrexone-treated animals. Histopathology parameters and cytokines level alterations in the colon of acetic acid-treated animals after BDL was reversed after injection of L-NAME, naltrexone, and co-administration of L-NAME (1 mg/kg) + naltrexone (5 mg/kg).

Conclusion

Cirrhosis improved the intestinal damages induced by acetic acid in rats which may be mediated through interaction of nitrergic and opioidergic systems.  相似文献   
25.
Brain Imaging and Behavior - The pathophysiology of migraine as a headache disorder is still undetermined. Diffusion tensor imaging (DTI) has significantly improved our knowledge about brain...  相似文献   
26.
Vasheghani  Maryam  Hessami  Zahra  Rekabi  Mahsa  Abedini  Atefeh  Qanavati  Akram 《Obesity surgery》2022,32(5):1689-1700
Obesity Surgery - Currently, pneumonia caused by the coronavirus disease 2019 (COVID-19) is a pandemic. To date, there is no specific antiviral treatment for the disease, and universal access to...  相似文献   
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28.

Background

Leishmaniasis has been identified as a major public health problem in tropical and sub-tropical countries. The present study was aimed to investigate antileishmanial effects of various extracts of Berberis vulgaris also its active compoenent, berberine against Leishmania tropica and L. infantum species on in vitro experiments.

Methods

In this study in vitro antileishmanial activity of various extracts of B. vulgaris also its active compoenent, berberine against promastigote and amastigote stages of L. tropica and L. infantum was evaluated, using MTT assay and in a macrophage model, respectively. Furthermore, infectivity rate and cytotoxicity effects of B. vulgaris and berberine in murine macrophage cells were investigated.

Results

The findings of optical density (OD) and IC50 indicated that B. vulgaris particulary berberine significantly (P<0.05) inhibited the growth rate of promastigote stage of L.tropica and L.infantum in comparison to meglumine antimoniate (MA). In addition, B. vulgaris and berberine significantly (P<0.05) decreased the mean number of amastigotes in each macrophage as compared with positive control. In the evaluation of cytotoxicity effects, it could be observed that berberine as compared with B. vulgaris exhibited more cytotoxicity against murine macrophages. Results also showed that when parasites were pre-incubated with B. vulgaris their ability to infect murine macrophages was significantly decreased.

Conclusion

B.vulgaris particularly berberine exhibited potent in vitro leishmanicidal effects against L. tropica and L.infantum. Further works are required to evaluate the antileishmanial effects of B.vulgaris on Leishmania species using clinical settings.  相似文献   
29.
Leishmania infantum is the most frequent cause of visceral leishmaniasis and L. tropica has been rarely linked to the disease in Iran. In this study, bone marrow aspirates were collected from 10 child patients, suspected with visceral leishmaniasis referred to the Pediatric Wards of Kerman Medical Hospitals, Kerman, Iran during 2002–2011. Leishmania species were identified by using nested PCR in all slides. The PCR samples from nine patients indicated L. infantum as principal causative agent of visceral leishmaniasis and one L.tropica as a minor species.  相似文献   
30.
The role of under- and overreporting of energy intake in determining the dietary patterns is yet unclear, especially in the Middle Eastern countries. This study identifies the prevalence of misreporting among Tehranian women aged 18-45 years and to compare the dietary intake patterns of plausible and all energy reporters. Dietary intakes and anthropometric data were collected. FitMate™ metabolic analyzer and Goldberg equation were used in determining the under/overreporting of energy intake. Underreporters were more likely to be overweight and older compared to plausible reporters. Three dietary patterns emerged for all reporters, and two were identified for plausible reporters. Using only plausible reporters to determine dietary patterns was not similar to using all reporters. The proportion of underreporters was 59.3% in the mixture cluster, 30.4% in the unhealthy cluster, and 35.3% in the healthy cluster (p<0.05). Underreporting of energy intake is not uniformly distributed among dietary pattern clusters and tends to be less severe among subjects in the unhealthy cluster. Our data suggested that misreporting of energy intake might affect the dietary pattern analysis.Key words: Dietary patterns, Energy underreporting, Validity, Women, Iran  相似文献   
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