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61.
申醒 《武汉体育学院学报》1999,(5)
观察了实验室自然光照对二乙酰一肟法测定血尿素结果的影响。发现光照对测量结果有显著影响。提示测量过程中要避免室外光直接照射 相似文献
62.
Using two experiments, this study aims to investigate how politically liberal or conservative message recipients respond to anti-tobacco appeals. The results show that in Study 1, respondents were exposed to a message about price policy. In Study 2, they were exposed to a message about a warning policy. In both studies, liberal participants more favorably evaluated anti-tobacco messages emphasizing feasibility rather than desirability, whereas conservative participants more positively evaluated messages emphasizing desirability rather than feasibility. Implications for policymakers and marketers are discussed. 相似文献
63.
Free radical generation and lipid peroxidation among the dry cell industry workers exposed to carbon
K. K. Reddy T. P. K. Reddy B. V. Somasekharaiah K. Soorya Kumari 《Indian journal of clinical biochemistry : IJCB》1998,13(1):27-32
A total of 75 healthy male dry cell industry workers exposed to carbon for 5, 8 and 10 years were compared with 48 controls
matched for age and economic status with respect to free radical generation, lipid peroxidation and antioxidant levels. Lymphocytes
were seperated from the whole blood and used for estimation of free radicals and antioxidants. Plasma lipid peroxidation products
were estimated in the form of thiobarbituric acid reactive substances. Significant increase in free radical generation and
lipid peroxidation products were observed in carbon exposed population than controls, and the increase was found to be significant
with increase in the period of exposure. The levels of antioxidants i.e., superoxide dismutase (SOD) and catalase were found
to decrease with the increase in exposure to carbon in industrial workers. These results suggest that exposure to carbon augments
free radical generation, lipid peroxidation and promotes decline in antioxidant enzymes. 相似文献
64.
大豆β-1,3-葡聚糖酶基因转化烟草及抗病性的研究 总被引:6,自引:0,他引:6
构建了大豆β-1,3-葡聚糖酶(β-1,3-glucanase)基因的植物表达载体pBI121-glu,并通过直接转化方法将其导入根癌农杆菌(A.tumefaciens)LBA4404受体菌中,构建了用于植物遗传转化的工程菌株LBA4404(pBI121-glu),并以烟草为转化对象进行了遗传转儿,获得了大量再生的转基因烟草.PCR,PCR-Southem以及Southem杂交检测结果表明目的基因已整合到烟草基因组中.转基因植株苗期抗立枯病实验表明,部分转化β-1,3-葡聚糖酶基因的工程烟草对立枯丝核菌(Rhizoctonia solani.)表明出不同程度的抗性提高. 相似文献
65.
Louise Spear-Swerling 《Reading and writing》2006,19(2):199-220
This study explored third-graders’ oral reading fluency (ORF) in easy text in relation to their third- and fourth-grade reading
comprehension. It also examined the children’s performance on two different measures of text exposure, a self-report questionnaire
and a title-recognition test. Although third-graders’ ORF related significantly to their reading comprehension, oral language
comprehension accounted for most of the variance in reading comprehension, whereas single word reading speed accounted for
most of the variance in ORF. Third-grade reading comprehension and ORF each predicted unique variance in children’s scores
on a fourth-grade state-mandated reading comprehension assessment. Scores on the self-report questionnaire correlated significantly
with third-grade ORF and fourth-grade reading; the self-report accounted for reliable variance in ORF even with all of the
other reading ability variables entered first. Results are consistent with the viewpoint that text exposure affects reading
fluency. They also demonstrate that ORF is a valuable predictor of middle-elementary children’s reading comprehension, even
when the ORF measure employs very easy text in which children achieve near-perfect word accuracy. 相似文献
66.
对烤烟3种常见病害进行分离计数,与BM高效腐熟剂对病害病原物影响对比,结果显示:BM高效腐熟剂在模拟条件下,使活体根结线虫Meloidogyne incognita雄虫数、雌虫数、卵囊数在10 d内分别减少61.31%、48.51%、49.22%;使烤烟黑胫病病原菌Phytophthora nicotiana、角斑病病原菌Pseudomonas angulata分别比对照减少97.68%、97.77%. 相似文献
67.
对羧基苯偶氮硫代若丹宁固相萃取光度法测定烟草及其添加剂中的汞 总被引:1,自引:0,他引:1
研究了对羧基苯偶氮硫代若丹宁 (CPATR)与汞的显色反应,在pH为3.5的醋酸-醋酸钠缓冲介质中,吐温-80存在下, CPATR与汞反应生成2:1稳定络合物,该络合物可被Waters Sep-Pak C18小柱固相萃取,用氮-氮二甲基甲酰胺(DMF)洗脱后用光度法测定,在洗脱液介质中,λmax=535 nm,体系摩尔吸光系数达8.70×103 m2/mol. 汞的质量浓度在0.05~4.0 mg/L内符合比尔定律. 该方法可用于烟草及其添加剂中汞含量的测定,结果满意. 相似文献
68.
皖西的水、肥、汽、热等自然资源丰富,适合优质烟的综合栽培技术措施的展开;适宜的烤烟良种为NC89,根据本地的降雨、土壤等自然条件,提出了一系列合理的施肥方法,适时的青苗移栽与轮作有密切联系,烟稻轮作在本地有良好的经济效益,且对烟叶的内外品质没有太明显的影响。 相似文献
69.
Many barriers restrict children’s access to nature resulting in negative consequences, including a lack of opportunities to learn and engage with the natural environment. Fortunately, environmental education programs offer participants an opportunity to counteract these challenges. While the benefits of environmental education as measured by pre-determined outcomes are well documented, research focused on participants’ perceptions and preferences related to their environmental learning experiences continues to be under-represented in the literature. Using a pre-/post-test survey approach, this study aimed to explore how an earth education summer camp, Sunship Earth TM, contributed to participants environmental learning experiences. Results suggest that Sunship Earth TM provides children with various EL opportunities that help to increase their understanding of some ecological concepts. Results also suggest that this learning experience may have helped to broaden participants’ understanding of environmental issues and actions, as well as enhance feelings of care, interest, and responsibility towards the environment. 相似文献
70.
晾晒烟感赤星病后游离氨基酸含量的研究 总被引:4,自引:0,他引:4
不同品种晾晒烟接种赤星菌后,游离氮基酸含量也不同。随品种抗病性由弱到强,碱性、芳香族、杂环族三类基酸全病程病健比下降,酸性、脂肪族、侧链为非极性、侧链不带电极性四类氨基酸则上升,酪、赖、精、胱等氨基酸下降,苯、组、脯、蛋、谷、天、丝、苏、甘、缬、亮等氨基酸上升。品种抗性越强,苯、酪、赖、精、组、脯、胱等氨基酸上升越早,消减也越快。游离氨基酸总增值量也随品种抗性增强而增大。 相似文献