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排序方式: 共有294条查询结果,搜索用时 15 毫秒
1.
目的探讨银杏叶制剂对急性脑梗死的治疗效果。方法随机选择银杏叶制剂配合治疗及常规药物治疗急性脑梗死患者各42例,对不同时期单光子发射电子计算机断层扫描(SPECT)、经颅多普勒超声检查(TCD)及血液流变学进行对比分析。结果银杏叶制剂配合治疗组治愈率及显效率明显高于常规药物治疗组(P<0.01);银杏叶治疗组血液流变学指标全血粘度及血浆粘度均明显降低(P<0.01);SPECT及TCD均示脑缺血病灶有不同程度改善,但常规药物治疗组血液流变学、SPECT、TCD改善均不明显。结论银杏叶制剂治疗急性脑梗死效果显著。  相似文献   
2.
仙人掌清除·OH自由基及对DNA损伤的保护作用   总被引:4,自引:0,他引:4  
目的研究野生仙人掌和食用仙人掌水提物清除·OH自由基及对DNA损伤的保护作用。方法采用现代生物化学发光技术,在CuSO4-Phen-Vc-H2O2-DNA化学发光体系中测定野生仙人掌和食用仙人掌清除·OH自由基及对DNA损伤的保护作用。采用紫外分光光度计测定野生仙人掌和食用仙人掌水提物中核酸和蛋白质的OD值。结果野生仙人掌能明显清除·OH自由基,抑制DNA的氧化损伤,对DNA氧化损伤的保护作用与其浓度之间存在正比性量效关系。食用仙人掌核酸和蛋白质的OD值为野生仙人掌的2.73倍和2.58倍,但不显示清除·OH自由基作用。结论野生仙人掌对·OH自由基引起的DNA损伤有明显的保护作用。食用仙人掌有较高的营养价值,但无抗DNA氧化损伤的作用。  相似文献   
3.

Analyses of the nutrients are given for the leaves of wild Plantago major L., P. lanceolata L. and P. media L., from different locations of the southeast of Spain. The proximate composition, mineral elements (Na, K, Ca, Mg, Fe, Cu, Zn, Mn and P), fatty acids, vitamins (vitamin C and carotenes), nitrate and oxalic acid were determined. The results show the low proportion of available carbohydrates, ranging from 1.99 g (P. major) to 2.81 g (P. lanceolata) (per 100 g fresh weight). Oxalic acid was found in low amounts, between 33.5 mg (P. media) and 88.2 mg (P. lanceolata) (100 g f wt). P. major had the highest amounts of vitamin C (45.1 mg/100g f. wt.) and calcium (108mg/100g f. wt.). Polyunsaturated fatty acids were high in all species, ranging from 38.97% (P. media) to 46.07% (P. lanceolata). Nutrient ratios (K/Na; Ca/P and oxalic acid/Ca) were found to be favourable in most cases.  相似文献   
4.
目的了解国家第四次下调盐碘含量前后珠海市居民食用碘盐的碘含量变化。方法按GB/T 13025.7-1999《直接滴定法》测定2011和2013年居民食用盐碘含量,利用SPSS 17.0统计软件,计算并比较分析调整前后碘含量变化。结果 2011年调整盐碘含量前和2013年调整后的珠海市碘盐覆盖率分别是98.67%和98.57%(P〉0.05);碘盐合格率分别为99.26%和94.56%(P〈0.01);碘盐含碘量均值分别是30.43和24.41mg/kg(P〈0.01)。结论珠海市调整盐碘含量政策得到落实,调整后的碘盐合格率下降。  相似文献   
5.
目的在微流控芯片上构建模拟人体血管的三维血管管道,实现管道间的物质交换,并形成有自主出芽功能的血管,为血管生成相关的疾病机制研究、药物筛选等提供良好的平台工具。方法利用微流控技术,采用被动进样方式,使人体脐静脉内皮细胞(human umbilical vein endothelial cells,HUVEC)在微流控芯片上自主贴壁生长形成三维血管管腔,构建体外仿生三维单管道血管和双管道血管芯片。在此基础上,开展对血管响应刺激因子出芽的功能的验证实验。结果体外仿生的双管道芯片的构建成功率达80%以上。在血管管道,内皮细胞无需借助外力支撑,在芯片上自主形成直径300μm±50μm,细胞分布均匀的、类似体内血管的三维血管管腔;物质通过模拟体内的扩散过程达到血管管道,使血管管腔响应物质刺激而出现功能性的血管出芽。结论体外仿生三维血管微流控芯片在体外实现了体内血管的结构与功能,模拟了体内物质扩散对血管生成的影响,可以用于生理过程中血管生成的体外动态观察。  相似文献   
6.
Mycotoxins are a group of toxic secondary metabolites produced in the food chain by fungi through the infection of crops both before and after harvest. Mycotoxins are one of the most important food safety concerns due to their severe poisonous and carcinogenic effects on humans and animals upon ingestion. In the last decade, insects have received wide attention as a highly nutritious, efficient and sustainable source of animal-derived protein and caloric energy for feed and food purposes. Many insects have been used to convert food waste into animal feed. As food waste might contain mycotoxins, research has been conducted on the metabolism and detoxification of mycotoxins by edible insects. The mycotoxins that have been studied include aflatoxins, fumonisins, zearalenone (ZEN), vomitoxin or deoxynivalenol (DON), and ochratoxins (OTAs). Aflatoxin metabolism is proved through the production of hydroxylated metabolites by NADPH-dependent reductases and hydroxylases by different insects. ZEN can be metabolized into α- and β-zearalenol. Three DON metabolites, 3-, 15-acetyl-DON, and DON-3-glucoside, have been identified in the insect DON metabolites. Unfortunately, the resulting metabolites, involved enzymes, and detoxification mechanisms of OTAs and fumonisins within insects have yet to be identified. Previous studies have been focused on the insect tolerance to mycotoxins and the produced metabolites; further research needs to be conducted to understand the exact enzymes and pathways that are involved.  相似文献   
7.
目的 了解中国市售食用植物油中氯丙醇酯和缩水甘油酯的污染状况.方法 采用同位素稀释-气相色谱-质谱联用法对2015-2017年全国市售1309份食用植物油样品中的总3-氯丙醇酯、2-氯丙醇酯和缩水甘油酯进行检测并对污染水平进行分析.结果 植物油中3-氯丙醇酯检出率为81.83%,平均值为1.21 mg/kg.其中茶油中...  相似文献   
8.
目的:调查药食两用薏苡仁中污染真菌多样性,为其安全使用提供参考依据。方法:收集薏苡仁样品18批,提取真菌DNA并扩增ITS2序列,基于Illumina MiSeq PE250平台进行高通量测序。结果:共检测到4门18纲44目99科149属的真菌,子囊菌门Ascomycota是最优势菌门,镰刀菌属Fusarium(3.05%~60.32%)是属水平最优势属,其次是曲霉属Aspergillus(2.20%~45.44%)、白僵菌属Beauveria(0.07%~63.21%)、链格孢属Alternaria(0.80%~11.92%)、Arachnomyces(0.03%~39.36%)和青霉属Penicillium(0.24%~8.03%)。此外,共检测到5种潜在产毒真菌,分别是烟曲霉A.fumigatus、土曲霉A.terreus、梨孢镰刀菌F.poae、囊状青霉P.capsulatum和展青霉P.paxilli。结论:高通量测序技术可以快速有效地检测薏苡仁中污染真菌种类,为薏苡仁污染真菌毒素提供风险预警。  相似文献   
9.
Most of the food packaging materials used in the market are petroleum-based plastics; such materials are neither biodegradable nor environmentally friendly and require years to decompose. To overcome these problems, biodegradable and edible materials are encouraged to be used because such materials degrade quickly due to the actions of bacteria, fungi, and other environmental effects. In this work, commonly available household materials such as gelatin, soy protein, corn starch, and papaya were used to prepare cost-effective lab-scale biodegradable and edible packaging film as an effective alternative to commercial plastics to reduce waste generation. Prepared films were characterized in terms of Fourier transform infrared spectroscopy (FTIR), water vapor transmission rate (WVTR), optical transparency, and tensile strength. FTIR confirmed the addition of papaya and soy protein to the gelatin backbone. WVTR of the gelatin-papaya films was recorded to be less than 50 g/m2/day. This water vapor barrier was five times better than films of pristine gelatin. The gelatin, papaya, and soy protein films exhibited transparencies of around 70% in the visible region. The tensile strength of the film was 2.44 MPa, which improved by a factor of 1.5 for the films containing papaya and soy protein. The barrier qualities of the gelatin and gelatin-papaya films maintained the properties even after going through 2000 bending cycles. From the results, it is inferred that the prepared films are ideally suitable for food encapsulation and their production on a larger scale can considerably cut down the plastic wastage.  相似文献   
10.
用噬菌体筛选抗癌药   总被引:9,自引:2,他引:9  
有些有诱导及(或)抗噬菌体的物质可能是抗癌药。我们用噬菌体对287种中草药进行了抗癌药初筛。结果显示:①14种中草药有诱导及抗噬菌体作用;②15种中草药仅有诱导作用;③28种中草药有强抗噬菌体作用。若进一步用肿瘤细胞培养或实验肿瘤动物进行筛选研究,这些中草药可作为首选药。  相似文献   
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