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酸雨对龙眼果树影响研究 总被引:2,自引:0,他引:2
通过大田和室内模拟试验,研究酸雨对龙眼果树的影响。结果表明酸雨使龙眼树叶、梢、芽的营养元素K、Mg、P、Fe、Zn、Mn渗出;叶绿素降低;酸雨中的H+、Cl-被吸收;细胞受损害,随着酸雨PH值下降,伤害程度加大,PH<3伤害是不可逆转的;Ca2+似有在逆境中迅速运输以起保护作用的倾向;每升含KH2PO4 1.0mg、Ca(NO3)2 3.3mg,FeSO442μg,H3BO329μg的混合液在酸雨之前或后喷淋果树,能降低伤害,浓度上限可至50倍。花、蕾、幼果受酸雨的伤害,程度是花>蕾>幼果,喷淋每升含Ca(NO3)23.3mg,KNO32.7mg,FeSO442μg的混合溶液可起保幼果作用。土壤肥沃、田间管理好、营养充分,能有效拮抗酸雨的侵害。 相似文献
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采用PXY104(含化学合成的HIV-env26肽基因4重串联体结构)为材料。温和裂解法提取质粒DNA,制备电泳纯化,Hind Ⅲ和EcoR Ⅰ酶解,低融点琼脂糖凝胶电泳回收HIV-DNA片段作为核酸探针;用[α-~(32)P]dATP通过缺口移位法标记,比放射性为4.05—6.69×10~7cpm/μgDNA通过分子杂交能测出lPg的靶DNA,初步试验结果表明,在本文试验条件下,可用该探针检测与之互补的核酸分子。 相似文献
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摘要 目的:分析2013~2017年黑龙江省居民疾病死亡构成情况,为提高全省居民的防病治病意识及加强居民的健康生活理念提供参考。方法:采用国家卫生统计网络直报系统及数理统计方法对2013~2017年全省居民疾病发病死亡构成变化进行分析。结果:全省居民死亡性别比例表现为男性高于女性,死亡年龄比例70岁以上最高,死因前三位依次为:循环系统疾病、肿瘤、呼吸系统疾病。循环系疾病中,以脑血管病、急性心梗、冠心病死亡率较高。结论:加强对循环系统疾病、恶性肿瘤及呼吸系统疾病的重点防治可能有助于减少本省疾病发病和死亡。 相似文献
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中华蜜蜂的欧洲幼虫腐臭病病原研究 总被引:1,自引:0,他引:1
采用中华蜜蜂Apis cerana cerana F.临床自然发病的欧洲幼虫腐臭病(European Foulbrood, EFB)幼虫,对其病原体进行了分离鉴定。结果表明:中华蜜蜂EFB的病原系蜂房蜜蜂球菌Melissococcus pluton。该菌为革兰氏阳性的兼性厌氧菌,形态学及染色特性、致病性试验、血清学试验和细菌DNA G+C mol%试验均证明中华蜜蜂和西方蜜蜂的EFB病原属于同属的蜂房蜜蜂球菌。生理生化特性结果与国外的早期研究结果相近似。该试验为不同地理位置、不同种寄主间蜂房蜜蜂球菌的遗传差异的研究,以及中华蜜蜂EFB病的防治学研究打下基础。 相似文献
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Hong-wei Bai Ye-yong Qian Bing-yi Shi Gang Li Yu Fan Zhen Wang Ming Yuan Lu-peng Liu 《PloS one》2013,8(11)
Background
Several case-control studies and cohort studies have investigated the association between fish intake and renal cancer risk, however, they yielded conflicting results. To our knowledge, a comprehensive assessment of the association between fish consumption and risk of renal cancer has not been reported. Hence, we conducted a systematic literature search and meta-analysis to quantify the association between fish consumption and renal cancer.Methods
A systematic search was performed using the PubMed, Embase, and Cochrane Library Central database for case-control and cohort studies that assessed fish intake and risk of renal cancer. Two authors independently assessed eligibility and extracted data. Fixed-effect and random-effect models were used to estimate summary relative risks (RR) and the corresponding 95% confidence intervals (CIs). Subgroup analyses, sensitivity analysis and cumulative meta-analysis were also performed.Results
A total of 12 case-control studies and three cohort studies published between 1990 and 2011 were included in the meta-analysis, involving 9,324 renal cancer cases and 608,753 participants. Meta-analysis showed that fish consumption did not significantly affect the risk of renal cancer (RR=0.99, 95% CI [0.92,1.07]). In our subgroup analyses, the results were not substantially affected by study design, region, gender, and confounder adjustments. Furthermore, sensitivity analysis confirmed the stability of results.Conclusions
The present meta-analysis suggested that there was no significant association between fish consumption and risk of renal cancer. More in-depth studies are warranted to report more detailed results, including stratified results by fish type, preparation method, and gender. 相似文献8.
用自制的苯基-琼脂糖CL-4B和羟基邻灰石等层析材料,从再生障碍性贫血病人尿中分离、纯化制得了红细胞生成素(EPO)。用多血小鼠红细胞~(56)Fe参入法测定该制品在体内的生物活力。用小鼠与人骨髓红系祖细胞培养法测其在体外的生物活力。实验结果说明,我们自制的EPO制品,不仅能用于动物,也能用于人骨贿红系祖细胞的培养。用Azocoll法测该制品中蛋白水解酶活力为阴性。 相似文献
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