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81.
BackgroundPhlebotomy is one of the most important steps in the preanalytical phase of a clinical laboratory process. In order to decrease phlebotomy errors, this specific procedure should be taught in detail by laboratory organizations. Our study aims to practice the training program on venous blood sampling and observe the close follow-up results.MethodsIn this observational study, 127 students who started their summer internship in Antalya Education and Research Hospital were given a one-day theoretical phlebotomy training in accordance with the Venous Blood Sampling Guidelines. After the theoretical training, phlebotomy applications of 10 students who were working in the field of out-patient blood sampling were observed both with and without their knowledge. A comprehensive checklist related to phlebotomy was created by the trainers in Antalya Education and Research Hospital and the observers answered each question as yes or no. For the statistical analysis, IBM SPSS Statistics 21.0 was used.ResultsAfter the theoretical education, the trainees were observed but no significant difference was found between the first and the second informed observations (p = 0.125). The students were observed three times more in the following week without their knowledge. There was a statistically significant difference between the first and the third unannounced observations (p=0.001).ConclusionsIn order to perform phlebotomy correctly, apart from theoretical education, a close follow-up is necessary too.  相似文献   
82.
贮食行为是动物应对食物资源的季节性和不可预测性变化的一种适应性生存策略。在群居性贮食动物中,同胎个体常表现出不同的贮食水平,而关于贮食行为与动物的个性和代谢水平之间的关系尚缺乏研究。本文以长爪沙鼠(Meriones unguiculatus)为对象,在筛选出具有高贮食和低贮食行为特征个体的基础上,比较了两组动物的个性特征(勇敢行为和探索能力)、静止代谢率、血清甲状腺激素水平、贮食期间的运动距离和贮食后的平均每日代谢率等。结果发现:高、低贮食长爪沙鼠的数量各占49%(22/45)和47%(21/45),两组动物之间的个性特征、静止代谢率和血清甲状腺激素均没有显著差异。在贮食期间高贮食个体的运动距离显著高于低贮食个体,且在停止贮食后,高贮食个体的平均每日代谢率显著低于低贮食个体。这些结果表明,在室内条件下,长爪沙鼠的贮食量高低与个性和静止代谢率无关,但高贮食个体会在停止贮食后降低其总能量消耗,以补偿贮食过程中的高能量代价。  相似文献   
83.
Carotenoids of 47 species of insects belonging to Hemiptera, including 16 species of Sternorrhyncha (aphids and a whitefly), 11 species of Auchenorrhyncha (planthoppers, leafhoppers, and cicadas), and 20 species of Heteroptera (stink bugs, assassin bugs, water striders, water scorpions, water bugs, and backswimmers), were investigated from the viewpoints of chemo-systematic and chemical ecology. In aphids, carotenoids belonging to the torulene biosynthetic pathway such as β-zeacarotene, β,ψ-carotene, and torulene, and carotenoids with a γ-end group such as β,γ-carotene and γ,γ-carotene were identified. Carotenoids belonging the torulene biosynthetic pathway and with a γ-end group were also present in water striders. On the other hand, β-carotene, β-cryptoxanthin, and lutein, which originated from dietary plants, were present in both stink bugs and leafhoppers. Assassin bugs also accumulated carotenoids from dietary insects. Trace amounts of carotenoids were detected in cicadas. Carotenoids of insects belonging to Hemiptera well-reflect their ecological life histories.  相似文献   
84.
BackgroundSeafood present important advantages for human nutrition, but it can also accumulate high levels of toxic and potentially toxic elements. Culinary treatments could influence seafood chemical element content and element bioavailability. In this study, the influence of culinary treatments on the total concentration and on the bioavailability of Cd, Cr, Cu and Pb in shark, shrimp, squid, oyster, and scallop was assessed.MethodsBoiling, frying, and sautéing with or without seasonings (salt, lemon juice and garlic) were evaluated. Total concentration and bioavailability of Cd, Cr, Cu and Pb in seafood after all these culinary treatments were compared with those in uncooked samples. Analytes were determined by triple-quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS). An alternative to express the results avoiding underestimated or overestimated values was proposed.ResultsThe analytes concentration in seafood without culinary treatment varied from 0.0030 μg g−1 (shrimp) to 0.338 μg g−1 (oyster) for Cd; 0.010 μg g−1 (squid) to 0.036 μg g−1 (oyster) for Cr; 0.088 μg g−1 (scallop) to 8.63 μg g−1 (oyster) for Cu, and < 0.005 μg g−1 (shrimp, squid and oyster) to 0.020 μg g−1 (shark) for Pb. Only Cd (in scallop) was influenced by culinary treatments (reduction from 37 to 53 % after boiling, frying, and sautéing). Bioavailability percentage varied from 11% (oyster) for Cd; 18% (oyster) to 41% (shark) for Cr; 6% (shark) for Cu, and 8% (oyster) for Pb. Bioavailability percentage was not influenced by culinary treatments.ConclusionCadmium concentration was reduced in scallop after some culinary treatments (reduction o 37-53% after boiling, frying, and sautéing), but bioavailability percentage was not influenced. The employed analytical method was adequate for the purpose, presenting import results for food safety assessment about the influence of culinary treatments on metals concentration and bioavailability in seafood.  相似文献   
85.
觅食是获取营养物质和能量的重要途经。对于栖息在四季分明地区的灵长类动物而言,低温以及食物资源相对匮乏的冬季是其生存和生长发育的瓶颈期。本研究以安徽黄山的野生藏酋猴(Macaca thibetana)天湖山群为对象,于2019年11月至2020年1月采用瞬时扫描取样法(Instantaneous scan sampling)采集猴群觅食行为数据,并分析其冬季食物组成及食物中各化学成分含量对取食的影响。结果显示,野生藏酋猴在冬季共取食23科31属34种植物,主要包括壳斗科(Fagaceae,21.62%)、樟科(Lauraceae,17.57%)、蔷薇科(Rosaceae,8.11%)的植物,取食部位以叶片(66.22%)和果实(种子)(24.32%)为主。不同取食部位的水分、总糖、淀粉、脂肪、单宁等成分存在显著差异。其中,叶片的水分含量高于果实(种子)、茎和芽,茎和果实(种子)含有较高的总糖,果实(种子)的淀粉和脂肪含量最高,芽的单宁含量最高。此外,取食植物中的总糖含量高于非取食植物。结果表明,野生藏酋猴适应寒冷冬季与食物匮乏的觅食策略是对植物种类、植物部位及其主要营养成分的综合结果。  相似文献   
86.
近年来,为了解决人类社会发展和环境资源的矛盾日益突出的问题,人造肉越来越多的进入人们的视野。通常所说的人造肉,可以分为植物蛋白肉和细胞培养肉。其中植物蛋白肉已经逐步开始商业化,细胞培养肉采用动物细胞进行培养,与真实肉制品更为接近。文中在分析细胞培养肉本质基础上,探讨细胞培养肉对肉类生产行业、消费者群体以及人类未来可持续发展的积极意义。在生物伦理学的视角下,研发和生产细胞培养肉有助于保障人类社会的可持续发展、提升动物福利、减少资源需求、改善肉制品营养功能,并为其他行业的发展提供新的增长点。此外,对于细胞培养肉生产涉及的食品安全、技术滥用、技术监管层面上的伦理风险提出进行了深入思考,希望能从生物伦理学的层面为人造肉行业的可持续发展提供参考。  相似文献   
87.
More than 68 billion chickens were produced globally in 2018, emphasising their major contribution to the production of protein for human consumption and the importance of their pathogens. Protozoan Eimeria spp. are the most economically significant parasites of chickens, incurring global costs of more than UK £10.4 billion per annum. Seven Eimeria spp. have long been recognised to infect chickens, with three additional cryptic operational taxonomic units (OTUs) first described more than 10 years ago. As the world’s farmers attempt to reduce reliance on routine use of antimicrobials in livestock production, replacing drugs that target a wide range of microbes with precise species- and sometimes strain-specific vaccines, the breakthrough of cryptic genetic types can pose serious problems. Consideration of biological characteristics including oocyst morphology, pathology caused during infection and pre-patent periods, combined with gene-coding sequences predicted from draft genome sequence assemblies, suggest that all three of these cryptic Eimeria OTUs possess sufficient genetic and biological diversity to be considered as new and distinct species. The ability of these OTUs to compromise chicken bodyweight gain and escape immunity induced by current commercially available anticoccidial vaccines indicates that they could pose a notable threat to chicken health, welfare, and productivity. We suggest the names Eimeria lata n. sp., Eimeria nagambie n. sp. and Eimeria zaria n. sp. for OTUs x, y and z, respectively, reflecting their appearance (x) or the origins of the first isolates of these novel species (y, z).  相似文献   
88.
为探明三氟苯嘧啶不同种子处理方式对稻飞虱的田间防治效果、防治时长以及对稻田蜘蛛和水稻的安全性,为该药剂种子处理防治稻飞虱提供科学依据,本研究设置10%三氟苯嘧啶悬浮剂按不同浓度(0.375、0.75、1.125和1.5 g a.i./kg种子)对水稻种子分别以干种子拌种(干拌)、清水浸种后拌种(湿拌)和药剂浸种3种方式,清水处理作为空白对照.结果表明,3种处理方式下的水稻发芽率和出苗率均与空白对照间无显著差异,播种后100 d,各浓度对稻飞虱的防治效果均在90%以上;当药剂浓度相同时,干拌与湿拌防治时长要优于药剂浸种;不同浓度三氟苯嘧啶药剂处理在3种方式下稻田蜘蛛种群数量均略低于空白对照田蜘蛛数量.因此,水稻生产中使用三氟苯嘧啶0.375~1.5 g a.i./kg种子干拌或湿拌处理,可有效降低田间稻飞虱种群数量,对天敌蜘蛛影响较小,对水稻种子发芽、出苗安全,可在水稻生产中推广使用.  相似文献   
89.
Pathogenic and spoilage fungi cause enormous challenges to food related fatal infections. Plant essential oil based classical emulsions can functions as antifungal agents. To investigate the antifungal spectrum, that is the scope of the nanoemulsion composed of Cleome viscosa essential oil and Triton-x-100 fabricated by ultrasonication method. Minimum inhibitory and fungicidal concentration of essential oil nanoemulsion (EONE) was tested against food borne pathogenic C. albicans. The MIC and MFC values ranged from 16.5 to 33 µl/ml with significant reduction on biofilm of C. albicans isolates. The alteration of molecular fingerprints was confirmed by Fourier transformed infrared spectroscopy and subsequent reduction of chitin levels in cell walls was noted by spectroscopic analysis. The EONE and their bioactive compounds cause collateral damage on C. albicans cells.  相似文献   
90.
Food producing animals harbouring bacteria carrying drug resistance genes especially the metallo-beta-lactamase (MBL) pose high risk for the human population. In addition, formation of biofilm by these drug resistant pathogens represents major threat to food safety and public health. In this study, metallo-β-lactamases (MβLs) producing Pseudomonas spp. from camel meat were isolated and assessed for their biofilm formation. Further, in vitro and in silico studies were performed to study the effect of flavone naringin on biofilm formation against isolated Pseudomonas spp. A total of 55% isolates were found to produce metallo-β-lactamase enzyme. Naringin mitigated biofilm formation of Pseudomonas isolates up to 57%. Disturbed biofilm architecture and reduced the colonization of bacteria on glass was observed under scanning electron microscope (SEM) and confocal laser scanning microscope (CLSM). The biofilm related traits such as exopolysaccharides (EPS) and alginate production was also reduced remarkably in the presence of naringin. Eradication of preformed biofilms (32–60%) was also observed at the respective 0.50 × MICs. Molecular docking revealed that naringin showed strong affinity towards docked proteins with binding energy ranging from −8.6 to −8.8 kcal mol−1. Presence of metallo-β-lactamase producers indicates that camel meat could be possible reservoir of drug-resistant Pseudomonas species of clinical importance. Naringin was successful in inhibiting biofilm formation as well as eradicating the preformed biofilms and demonstrated strong binding affinity towards biofilm associated protein. Thus, it is envisaged that naringin could be exploited as food preservative especially against the biofilm forming food-borne Pseudomonas species and is a promising prospect for the treatment of biofilm based infections.  相似文献   
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