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91.
Summary This short paper summarizes the basic concept and the technology of a new computed radiographic system which uses an energy-storage phosphorus panel called Imaging Plate as an image sensor. The Imaging Plate can be used to obtain radiographs in exactly the same way as the screen-film combination is used in conventional radiography. The system eliminates the drawbacks of conventional screen-film radiography by combining digital image processing and digitization of the x-ray energy pattern utilizing scanning laser stimulated luminescence.The major part of this paper was originally delivered at the 1984 AAPM Annual Summer School which was held on July 22–27 at University of Notre Dame, USA. Modified for the publication in the Neurosurgical Review.  相似文献   
92.
Metabolic syndrome (MetS) characteristics include chronic inflammation and elevated oxidative stress. This study assessed associations between circulating concentrations of micronutrients/phytochemicals and inflammatory/oxidative stress markers with MetS and MetS components. Adults (N = 606) from the European Health Examination Survey in Luxembourg (2013–2015) were randomly selected. We performed a multivariable logistic regression model using the least absolute shrinkage and selection operator to identify MetS-associated variables. Participants with MetS had higher concentrations of C-reactive protein (CRP), 8-iso-prostaglandin F2α, leptin, insulin, and vitamins E/A, but lower concentrations of adiponectin, beta-carotene, and oxidized low-density lipoprotein. A one-unit increase in log-CRP was associated with 51% greater odds of MetS (OR = 1.51 (95% CI: 1.16, 1.98)). Adults with a one-unit increase in log-leptin were 3.1 times more likely to have MetS (3.10 (2.10, 4.72)). Women with a one-unit increase in vitamin A were associated with 3% increased odds of MetS (1.03 (1.01, 1.05)), while those with a one-unit increase in log-adiponectin were associated with 82% decreased odds (0.18 (0.07, 0.46)). Chronic inflammation best characterized adults with MetS, as CRP, adiponectin, and leptin were selected as the main MetS determinants. Micronutrients did not seem to affect MetS, except for vitamin A in women.  相似文献   
93.
This paper continues the systematic review on proanthocyanidins and flavan-3-ols in the prevention and treatment of periodontal disease and covers the immunomodulatory effects, and animal- and clinical studies, while the other part discussed the direct antibacterial properties. Inflammation as a major response of the periodontal tissues attacked by pathogenic microbes can significantly exacerbate the condition. However, the bidirectional activity of phytochemicals that simultaneously inhibit bacterial proliferation and proinflammatory signaling can provide a substantial alleviation of both cause and symptoms. The modulatory effects on various aspects of inflammatory and overall immune response are covered, including confirmed and postulated mechanisms of action, structure activity relationships and molecular targets. Further, the clinical relevance of flavan-3-ols and available outcomes from clinical studies is analyzed and discussed. Among the numerous natural sources of flavan-3-ols and proanthocyanidins the most promising are, similarly to antibacterial properties, constituents of various foods, such as fruits of Vaccinium species, tea leaves, grape seeds, and tannin-rich medicinal herbs. Despite a vast amount of in vitro and cell-based evidence of immunomodulatory there are still only a few animal and clinical studies. Most of the reports, regardless of the used model, indicated the efficiency of these phytochemicals from cranberries and other Vaccinium species and tea extracts (green or black). Other sources such as grape seeds and traditional medicinal plants, were seldom. In conclusion, the potential of flavan-3-ols and their derivatives in prevention and alleviation of periodontal disease is remarkable but clinical evidence is urgently needed for issuing credible dietary recommendation and complementary treatments.  相似文献   
94.
Background: Polydatin is a stilbenoid with important antioxidant, anti-inflammatory, and immunomodulating properties. The aim of this study was to assess the anti-inflammatory preventive effect of polydatin in the mouse model of acute arthritis induced by calcium pyrophosphate (CPP) crystals. Methods: Acute arthritis was induced by the injection of a suspension of sterile CPP crystals into the ankle joint of Balb/c mice. Animals were randomized to receive polydatin or colchicine (the control drug) according to a prophylactic and a therapeutic protocol. The primary outcome was the variation of ankle swelling obtained after crystal injection and treatment, while histological parameters such as leukocyte infiltration, IL-1ß and CXCL1 levels and tissue expression were considered as secondary outcomes. Results: Prophylactic treatment with PD significantly diminished ankle swelling after 48 h from crystal injection. Secondary outcomes such as leukocyte infiltration, necrosis, edema, and synovitis were also decreased. PD caused a reduction in circulating levels of IL-1ß and CXCL1, as well as their tissue expression. By contrast, the therapeutic administration of PD did not have any beneficial effect. Conclusions: PD can effectively prevent acute inflammatory response to crystals in the mouse model of CPP crystal-induced arthritis. These results suggest that this bioactive compound might be used in the prevention of crystal-induced acute attacks in humans.  相似文献   
95.
扶芳藤化学成分研究   总被引:12,自引:0,他引:12  
目的:对扶芳藤的化学成分进行研究。方法:乙醇提取,硅胶柱色谱分离,葡聚糖色谱纯化,核磁、质谱、紫外、红外光谱及理化常数鉴定结构。结果:从氯仿提取液中分离鉴定了6个化合物,分别为刺苞木脂素A(1),3-O-咖啡酰基白桦酯醇(Ⅰ),3-O-咖啡酰基羽扇豆醇(Ⅱ),丁香脂素(Ⅳ),1,4-二羟基-2-甲氧基苯(Ⅴ),胡萝卜苷(Ⅵ)。结论:6个化合物均为首次从该植物中获得,而且化合物(Ⅰ)为新化合物。  相似文献   
96.
Objective: The present study aimed to evaluate the therapeutic effect and explore the underlying mechanisms of Longxue Tongluo Capsule (LTC) on ischemic stroke rats. Methods: Twenty-six rats were randomly divided into four groups, including sham group, sham + LTC group, MCAO group, and MCAO + LTC group. Ischemic stroke rats were simulated by middle cerebral artery occlusion (MCAO), and LTC treatment group were orally administrated with 300 mg/kg of LTC once daily for seven consecutive days. LTC therapy was validated in terms of neurobehavioral abnormality evaluation, cerebral infarct area, and histological assessments. The plasma metabolome comparisons amongst different groups were conducted by UHPLC-Q Exactive MS in combination with subsequent multivariate statistical analysis, aiming to finding the molecules in respond to the surgery or LTC treatment. Results: Intragastric administration of LTC significantly decreased not only the neurobehavioral abnormality scores but also the cerebral infarct area of MCAO rats. The interstitial edema, atrophy, and pyknosis of glial and neuronal cells occurred in the infarcted area, core area, and marginal area of cerebral cortex were improved after LTC treatment. A total of 13 potential biomarkers were observed, and Youden index of 11 biomarkers such as LysoPC, SM, and PE were more than 0.7, which were involved in neuroprotective process. The correlation and pathway analysis showed that LTC was beneficial to ischemic stroke rats via regulating glycerophospholipid and sphingolipid metabolism, together with nicotinate and nicotinamide metabolism. Heatmap and ternary analysis indicated the synergistic effect of carbohydrates and lipids may be induced by flavonoid intake from LTC. Conclusion: The present study could provide evidence that metabolomics, as systematic approach, revealed its capacity to evaluate the holistic efficacy of TCM, and investigate the molecular mechanism underlying the clinical treatment of LTC on ischemic stroke.  相似文献   
97.
ObjectiveTo know the perception and opinion of primary care health professionals on the impact of non-medicalizing group educational intervention (GRUSE) with women who present somatic symptoms without organic cause.DesignQualitative phenomenological study.SettingPrimary care health centers in Andalusia, during 2017 and 2018.Participants and/or contextsTwenty-four health professionals, selected according to their level of involvement in the GRUSE strategy (socio-educational groups).MethodA qualitative methodology is applied, through the phenomenological method. The technique used to collect the information is the discussion group, and a content analysis is carried out on it. The software Atlas.ti 8.0 is used as a support resource for the analysis.ResultsHealth professionals highlight group work as a means of achieving change, and point to the importance of intervention as a non-medicalizing strategy. They perceive that the participants obtain some benefits: the improvement of their personal well-being, the increase of their self-esteem and self-determination, and the generation of social networks, benefits that also affect their immediate surroundings.ConclusionsIn the opinion of the professionals, the strategy has positive effects on women and does not mean an increase in resources for the health system. In addition, they express the importance of provide women with tools to cope with daily life problems derivates mostly from gender mandates of a patriarchal society.  相似文献   
98.
99.
The development of a specific and sensitive immunologic ELISA detection system for methylphosphonoflouridic acid. 1,2,2-trimethylpropylester (soman) by the use of monoclonal antibodies (MAbs) is described. The monoclonal antibodies F71D7, F71H10, F71B12 and F71H9 originally produced against the soman derivative methyl phosphonic acid,p-aminophenyl 1,2,2-trimethylpropyldiester (MATP) also reacted with soman in a previously developed, direct competitive ELISA. After optimizing the ELISA system by varying the reaction mixture and the solvents for the organophosphate, 5.0×10–7 mol/l soman (80% purity), e.g. 2.5 ng or 2 ng pure soman per 25 l test buffer, could be detected after a total test duration of 40 min. A shortening of the incubation time to 10 min resulted in a drop of sensitivity to 1.8×10–6 mol/l soman. Various alcohols which may be used as extraction media for soman from various materials (isopropanol, ethanol and methanol) were shown to inhibit peroxidase activity and thereby reduce the sensitivity of the test. However, the influence of alcohols decreased with the shortening of incubation time. All monoclonal antibodies showed little cross reactivity to sarin and no cross reactivity to tabun and VX. Judging on the reactivity of the MAbs with MATP and soman oxidazed by 1,2-dihydrobenzol, some reactivity with some other (non-toxic) soman analogues containing the same pinacolyl group can be expected. There was no evidence for stereoselectivity of the MAbs tested. Finally, soman could be detected in different biological samples like human serum, goat serum, rabbit serum, chicken serum, milk, and tap water in concentrations between 1.3×10–6 and 2.0×10–6 mol/l.  相似文献   
100.
四乙基胺抑制蟾酥的强心效应   总被引:1,自引:0,他引:1  
[目的]观察蟾酥对离体蟾蜍心脏收缩运动的影响和各种受体阻断剂、钾通道阻断剂对这种效应的影响。[方法]将离体蟾蜍心脏收缩运动用张力换能器转换成电信号,通过Doctor-95 Super Lab软件系统在电脑上连续记录心率和收缩力的变化,并打印成曲线。[结果]取自蟾蜍同体耳后腺的蟾酥对离体蟾蜍心脏收缩运动有增强作用。M受体阻断剂阿托品(0.5g/L)和β受体阻断剂心得安(0.01g/L)不能阻断蟾酥对离体蟾蜍心脏收缩运动的增强作用,而α受体阻断剂酚妥拉明(0.5g/L)、非选择性钾通道阻断剂四乙基胺(10mmol/L)则明显抑制蟾酥对离体蟾蜍心脏收缩运动的增强作用。[结论]蟾酥是通过α受体作用于钾通道而增强离体蟾蜍心脏收缩运动。  相似文献   
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