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51.
In electromagnetic dosimetry, anatomical human models are commonly obtained by segmentation of magnetic resonance imaging or computed tomography scans. In this paper, a human head model extracted from thermal infrared images is examined in terms of its applicability to specific absorption rate (SAR) calculations. Since thermal scans are two-dimensional (2D) representation of surface temperature, this allows researchers to overcome the extensive computational demand associated with 3D simulation. The numerical calculations are performed using the finite-difference time-domain method with mesh sizes of 2 mm at 900 MHz plane wave irradiation. The power density of the incident plane wave is assumed to be 10 W/m2. Computations were compared with a realistic anatomical head model. The results show that although there were marked differences in the local SAR distribution in the various tissues in the two models, the 1 g peak SAR values are approximately similar in the two models. 相似文献
52.
Sharmistha Sinha Akram Astani Tuhin Ghosh Paul Schnitzler Bimalendu Ray 《Phytochemistry》2010,71(2-3):235-242
Herpes simplex viruses (HSVs) display affinity for cell-surface heparan sulfate proteoglycans with biological relevance in virus entry. Here, we exploit an approach to inhibiting HSV infection by using a sulfated fucoidan, and a guluronic acid-rich alginate derived from Sargassum tenerrimum, mimicking the active domain of the entry receptor. These macromolecules have apparent molecular masses of 30 ± 5 and 26 ± 5 kDa, respectively. They and their chemically sulfated derivatives showed activity against herpes simplex virus type 1 (HSV-1). Their inhibitory concentration 50% (IC50) values were in the range 0.5–15 μg/ml and they lacked cytotoxicity at concentrations up to 1000 μg/ml. The anti-HSV activity increased with increasing sulfate ester content. Our results suggest the feasibility of inhibiting HSV infection by blocking viral entry with polysaccharide having specific structure. 相似文献
53.
Sadegh Feizollahzadeh Reza Ghiasvand Abbas Rezaei Hossein Khanahmad Akram sadeghi Mitra Hariri 《Probiotics and antimicrobial proteins》2017,9(1):41-47
Probiotic therapies are going to be an effective alternative therapeutic strategy in the treatment and management of diabetes. The mechanism behind the essential effects of probiotic therapies in diabetic patients was not fully understood. The objective of this study was to evaluate the effects of probiotic soy milk containing Lactobacillus planetarum A7 on inflammation, lipid profile, fasting blood glucose, and serum adiponectin among patients with type 2 diabetes mellitus. Forty patients with type 2 diabetes, at the age of 35–68 years old, were assigned to two groups in this randomized, double-blind, controlled clinical trial. The patients in the intervention group consumed 200 ml/day of probiotic soy milk containing L. planetarum A7 and those in control group consumed 200 ml/day of pure soy milk for 8 weeks. Serum TNF-α, C reactive protein, adiponectin, lipid profile, and fasting blood glucose were determined before and after intervention. In intervention group, serum adiponectin in pre- and post-treatment did not show any significant changes (2.52 ± 0.74 vs 2.84 ± 0.61, P = 0.658), as well as changes in serum TNF-α and C reactive protein (172.44 ± 5.7 vs 172.83 ± 7.6, P = 0.278, 4.2 ± 1.4 vs 4.5 ± 1.9, P = 0.765, respectively). Low-density cholesterol and high-density cholesterol changed significantly (P = 0.023, P = 0.017, respectively), but fasting blood glucose did not show any significant changes. The results of this study showed that consumption of probiotic soy milk and soy milk has no effect on serum adiponectin and inflammation, but it can change lipid profile among type 2 diabetic patients. 相似文献
54.
Kafeel Ahmad Asma Ashfaq Muhammad Ashraf Nudrat Aisha Akram Sumaira Yasmin 《人类与生态风险评估》2016,22(3):597-610
Levels of Mo, As, Se, Fe, Cu, Zn, Ni, and Pb were determined in a vegetable commonly consumed in Pakistan. Samples were collected from three different sites (Ratokala, Phularwan, and Mailowal) supplied with three different water sources. Mo and Pb in water and Mo and As in C. sativum were higher than the suggested standards at the international level. Lower bioconcentration factor and pollution load index were seen at Site-I than at other sites. A positive association was found between the rhizosphere metals and those of the vegetable at all three sites. Enrichment factor at three sites ranged from 0.28 to 10.39. The highest value of daily intake of metals was found for Fe (0.245 mg/kg/day) and of the health risk index for As (70.41) at the wastewater inundated site. It is inferred that uptake of Mo, As, Cu, Ni, and Pb through C. sativum represents a high health danger to the individuals using this vegetable. 相似文献
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56.
Helen L. Henry Chhanda Dutta Noreen Cunningham Raymond Blanchard Robert Penny Chilung Tang Gail Marchetto Shu-Yin Chou 《The Journal of steroid biochemistry and molecular biology》1992,41(3-8)
The synthesis of 1,25(OH)2D3 is a critical control point in the regulation of calcium metabolism, and possibly in the growth and differentiation of a number of cell types. This paper reviews our current understanding of the regulation of this process at the cellular and molecular levels, with the emphasis on the mechanisms of feedback control 1,25(OH)2D3 itself, control of parathyroid hormone, the roles of cyclic AMP dependent protein kinase and protein kinase C, and the interaction between the various intracellular regulators of 1,25(OH)2D3 production. 相似文献
57.
58.
Background
The spread of agriculture into Europe and the ancestry of the first European farmers have been subjects of debate and controversy among geneticists, archaeologists, linguists and anthropologists. Debates have centred on the extent to which the transition was associated with the active migration of people as opposed to the diffusion of cultural practices. Recent studies have shown that patterns of human cranial shape variation can be employed as a reliable proxy for the neutral genetic relationships of human populations.Methodology/Principal Findings
Here, we employ measurements of Mesolithic (hunter-gatherers) and Neolithic (farmers) crania from Southwest Asia and Europe to test several alternative population dispersal and hunter-farmer gene-flow models. We base our alternative hypothetical models on a null evolutionary model of isolation-by-geographic and temporal distance. Partial Mantel tests were used to assess the congruence between craniometric distance and each of the geographic model matrices, while controlling for temporal distance. Our results demonstrate that the craniometric data fit a model of continuous dispersal of people (and their genes) from Southwest Asia to Europe significantly better than a null model of cultural diffusion.Conclusions/Significance
Therefore, this study does not support the assertion that farming in Europe solely involved the adoption of technologies and ideas from Southwest Asia by indigenous Mesolithic hunter-gatherers. Moreover, the results highlight the utility of craniometric data for assessing patterns of past population dispersal and gene flow. 相似文献59.
Recreational boats in tow between lakes are a known vector of the spread of aquatic invading species (AIS), but we have no test of the hypothesis that recreational boats are also a vector of secondary spread of AIS among freshwater ecosystems via in-water transport i.e., while boating between interconnected waterways. In this study, we surveyed recreational boaters travelling into Lake Simcoe (44°25′N, 79°20′W), Ontario, Canada, on their recreational activities, boat maintenance, and travel destinations, measured the degree of vessel fouling, and sampled all standing water and attached macrophytes associated with their vessels. A total of 321 zooplankton individuals comprising 15 different species were collected from the standing water in vessels, including veligers of the invasive zebra mussel Dreissena. The volume of water collected within the vessels significantly increased the number of zooplankton transported. Zooplankton species from pelagic habitats or with planktonic life stages were collected more frequently than species that occupy littoral or benthic habitats, likely reflecting the recreational activities of boaters. Patterns of boater activities, movements and hygiene habits, suggest recreational boating in the Lake Simcoe region is contributing to the spread of native and invasive species into nearby waterways. Our study validates the widespread assumption that recreational boats are an important in-water vector for the secondary spread of both native and invasive zooplankton species. Future management strategies to reduce the spread of AIS should be aimed at increasing awareness of boater hygiene practices, particularly the frequent draining of standing water. 相似文献
60.
Neghal Kandiyil Nishath Altaf Akram A. Hosseini Shane T. MacSweeney Dorothee P. Auer 《PloS one》2012,7(10)