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排序方式: 共有368条查询结果,搜索用时 15 毫秒
1.
血液标本放置时间和抗凝剂对血糖检测结果的影响 总被引:5,自引:0,他引:5
目的 :探讨两种抗凝剂的血液标本放置时间对血糖测定的影响。方法 :采集门诊健康人血液标本 30份 ,分别以肝素钠和氟化钠作抗凝 ,放置不同时间检测血糖值。结果 :及时分离血浆的血液标本血糖在 5h内差异无显著性。而血液离体后不及时分离血浆 ,血糖是随着时间延长而降低。氟化钠抗凝的血糖比肝素钠抗凝的血糖下降的程度要缓慢一些 ,所以临床上采集血液标本必须及时分离血浆 ,选用合适的抗凝剂 ,及时测定 ,减少误差 ,提高准确性 ,给临床提供准确的诊断依据 相似文献
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Controlled release of sugar and toxicant from a novel device for controlling pest insects 总被引:1,自引:0,他引:1
Xing Ping Hu Baruch S. Shasha Michael R. McGuire Ronald J. Prokopy 《Journal of controlled release》1998,50(1-3):257-265
A novel biodegradable device, designed for long-lasting residual effectiveness of feeding stimulant (sugar) and insecticide (dimethoate) against apple maggot flies and other insects, was formulated. The device is an 8-cm diameter fruit-mimicking sphere, consisting of 42–50% sugar entrapped in a mixture of gelatinized corn flour and wheat flour in the presence of glycerin, and coated with a layer of latex paint containing dimethoate and sugar. We found that the outer layer of paint prevents cracking of the sphere upon drying and creates a barrier to control the release of both sugar and dimethoate. Releases of each ingredient were screened first by chemical analysis and then by bioassays in the laboratory and in field cages against apple maggot flies. Chemical analysis demonstrated strong potential for controlled release of water-soluble feeding stimulant and water-insoluble insecticide measured as a function of the amount of rainfall and duration of exposure time. Field results showed greater than 70% insecticidal activity after 11 weeks of sphere exposure in an orchard. This device has the potential to be used for a variety of insect-control applications through manipulating its shape, color and texture into forms known to be attractive to target insects, and by employing various toxicants designed to be effective against such insects. 相似文献
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目的了解消化道肿瘤患者手术治疗前后肠道通透性的改变,探讨肠黏膜屏障功能是否受腹部手术的影响。方法选择手术治疗消化道肿瘤患者16例,在术前、术后1周口服乳果糖、甘露醇液后采集6小时尿样,尿样和乳果糖、甘露醇的标准样经肟化处理后通过气相色谱分析仪糖分子探针法进行检测分析其含量及比值。结果甘露醇峰、乳果糖峰出峰时间稳定,峰面积随含量增加而增加,并且呈线性相关;消化道肿瘤手术前后尿样中的乳果糖含量和乳果糖/甘露醇有显著性差异,乳果糖含量增高,而甘露醇含量手术前后无显著性差异。结论消化道肿瘤手术会导致肠黏膜通透性增加,出现肠黏膜屏障功能损害。 相似文献
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Paolo E. Puddu Alessandro Menotti 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(7):1949-1952
AimsFor several decades, there has been a notion that dietary fat is made of different components (at least SAFA, MUFA, and PUFA) that exhibit different and sometimes contrasting effects when associated with health and diseases: coronary heart disease (CHD) and cardiovascular diseases (CVD) in general. A similar fact is not noticed in carbohydrates and their components considering that even some major recent studies on the issue did not segregate simple carbohydrates from complex carbohydrates. In this study, we aimed to stress this need.Data synthesisA small number of selected studies are presented and commented where segregation of simple from complex carbohydrates was either performed or disregarded to address the inconsistency of not disentangling them.ConclusionsIf only total fats were considered in investigations where fat was studied, the present notion and attitude toward different roles of the various classes of fats, at least SAFA versus unsaturated (MUFA and PUFA) would be missing. Therefore, there is a need to disentangle simple from complex carbohydrates, and this should be systematically applied when addressing CHD or CVD mortality risks and their preventive measures. 相似文献
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ObjectiveThe aim was to investigate the effect of maltodextrin and sucrose association on the acidogenic and adherence profiles of cariogenic bacteria.DesignStreptococcus mutans (S. mutans) and Lactobacillus casei (L. casei) were cultivated in culture medium containing maltodextrin, sucrose, maltodextrin–sucrose mixture or glucose. Analyses of the acidogenicity and microbial adherence were conducted in triplicate for each microorganism and tested carbohydrate.ResultsFor L. casei, maltodextrin, sucrose and maltodextrin–sucrose mixture showed lower acidogenic potential compared to glucose. When the microorganism was S. mutans, sucrose and maltodextrin–sucrose mixture presented higher acidogenic potential compared to maltodextrin and glucose. Microbial adherence analysis revealed higher adherence for S. mutans in presence of sucrose and maltodextrin–sucrose mixture compared to maltodextrin and glucose. For L. casei, all the carbohydrates showed similar adherence percentages.ConclusionThe addition of maltodextrin to sucrose does not increase the cariogenicity of sucrose in terms of acidogenicity and adherence of the cariogenic bacteria. 相似文献
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ObjectiveTo investigate the acid-producing capacity from sugars and sugar alcohols of oral Lactobacillus collected in connection with radiation therapy (RT) to the head and neck region.DesignLactobacillus were collected from the tongue, buccal mucosa and supragingival plaque in 24 patients before, during, and after RT. The acid-producing capacity of Lactobacillus isolates (n = 211) was analyzed using a colorimetric fermentation test in microtiter plates. Solutions containing 2% sugars (sucrose, glucose, fructose, lactose) or sugar-alcohols (sorbitol and xylitol) were used. After 24 h of incubation, bacterial acid-producing capacity was determined as strong (pH < 5), weak (pH ≥5–≤ 6) or low/absent (pH > 6). Data regarding intake frequency of sugar-rich products and products with sugar-alcohols was collected.ResultsThe highest acid-producing capacity using the sugars was seen for isolates collected during RT. Sorbitol was fermented to a higher extent during and post RT, especially among isolates from plaque. Lactobacillus fermenting xylitol showed the highest acid-producing capacity during RT (p < 0.05). No statistically significant correlations between stimulated whole salivary secretion rate and acid-producing capacity, or between the intake frequency of sugar-rich products or sugar-alcohol containing products and Lactobacillus acid-producing capacity, were found.ConclusionThe results suggest that Lactobacillus isolates, collected from the tongue, buccal mucosa and supragingival plaque, have a higher acid-producing capacity using sugars and sugar-alcohols during RT than one year post RT. 相似文献
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目的 掌握广西辖区内糖厂密封放射源的使用分布情况,评价密封放射源对周围环境、职业人员、公众成员产生的辐射影响,为今后糖厂放射源的使用管理提供科学依据。方法 按监测规范合理布点,利用γ辐射剂量率仪对广西区内所有使用密封放射源的糖厂开展辐射环境现场测量,根据监测结果进行估算,并结合个人剂量监测结果进行分析。结果 密封放射源使用场所周围辐射剂量率高于环境本底水平,职业人员、公众成员会受到一定的辐射剂量。结论 职业人员及公众成员年有效剂量结果符合相关要求。 相似文献