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101.
吕国梁 《闽西职业技术学院学报》2005,7(3):122-124
在龙岩中心城市行道树的树种种类、数量、规格及生长量实地调查的基础上,对14种主要行道树进行生长量分析比较,综合评价它们的适宜性,结果表明大叶榕、菩提、天竺桂等三种适宜性为优秀,樟树、石栗、洋紫荆、海枣、盆架木、黄花槐、桃花心木、木棉等八种适宜性为良好。为龙岩中心城市行道树种的选择提供依据。 相似文献
102.
Kenneth W. Hunt 《The Journal of environmental education》2013,44(3):30-32
Abstract The authors constructed a 32-item survey instrument to measure knowledge and aspects of attitudes (issue understanding and concern, locus of control, and verbal commitment) regarding sea turtle conservation on Zakynthos, Greece. It was completed by 332 5th and 6th grade students from 21 classes in 3 geographic settings. The results indicate low knowledge scores, but high score levels for attitudes. Knowledge, understanding and/or concern, and locus of control significantly correlated with grade level. Overall, a significant positive correlation between knowledge and attitudes was demonstrated. The findings of the study may be useful in designing environmental education programs to promote sea turtle conservation. 相似文献
103.
Aquatic invasive species (AIS) present a great challenge to ecosystems around the globe, and controlling AIS becomes increasingly difficult when the potential vectors are related to recreational activities. An approach combining education and outreach efforts to control AIS may be the best course of action. A survey was designed to measure public perceptions, knowledge of, and attitudes towards AIS, as well as public support for various management actions. Surveys were administered during the summer of 2013 at two boat launches where one launch had active outreach the previous summer and one that did not. A total of 400 surveys were completed with a response rate of 89%. There was support for most proposed management options, and respondents understood the urgency of managing AIS. There was a difference between the launches in how people responded, highlighting that educational programming may need to be tailored for specific recreational uses and recreational settings. 相似文献
104.
高邮市家鹅球虫种类的调查与鉴定 总被引:2,自引:0,他引:2
采用卵囊形态结构特征观察与回归动物试验相结合的方法,对江苏省高邮市家鹅感染球虫的种类进行了调查与鉴定.共查16个鹅群,球虫阳性16群,阳性率为100%.共检到1科2属6种球虫,其中艾美耳属(Eimeria)5种:鹅艾美耳球虫(E.anseris)、棕黄艾美耳球虫(E.fulva)、赫曼艾美耳球虫(E.her-mani)、有害艾美耳球虫(E.nocens)和多斑艾美耳球虫(E.stigmosa);泰泽属(Tyzzeria)1种:稍小泰泽球虫(T. parvula).稍小泰泽球虫检出率最高(100%,16/16),其次是赫氏艾美耳球虫(50.0%,8/16),为本次调查的优势种. 相似文献
105.
The living system on earth is largely using oxygen for burning metabolic fuel for energy. The toxicity of oxygen is largely due to the formation of free radicals in living systems. Stress is also responsible for the generation of free radicals. The evidence for the involvement of free radicals and oxidative injury in producing metabolic disturbance, maladjustment and many diseases has been accumulating since long. It is largely believed that the root cause of many chronic diseases is stress induced free radicals and resultant oxidative injury. 相似文献
106.
107.
D-氨基酸在食品中广泛存在。研究D-氨基酸诱导的酿酒酵母细胞内的活性氧的累积及其生物损伤。实验结果显示D-氨基酸抑制细胞生长,引起细胞内H2O2含量的升高,导致细胞内过氧化氢酶和过氧化物酶的活性增强。该结果表明H2O2是D-氨基酸诱导产生的活性氧的主要类型,氧化损伤是D-氨基酸对酿酒细胞毒性的主要机制。 相似文献
108.
Patrick C.Y.WOO Samson S.Y.WONG Jade L.L.TENG Kit-Wah LEUNG Antonio H.Y.NGAN Herman TSE Susanna K.P.LAU Kwok-Yung YUEN 《Journal of Zhejiang University. Science. B》2010,11(6):391-401
A straight, non-sporulating, Gram-variable bacillus (HKU24T) was recovered from the blood culture of a patient with metastatic breast carcinoma. After repeated subculturing in BACTEC Plus Anaerobic/F blood culture broth, HKU24T grew on brucella agar as non-hemolytic, pinpoint colonies after 96 h of incubation at 37 °C in an anaerobic environment and aerobic environment with 5% CO2. Growth was enhanced with a streak of Staphylococcus aureus. HKU24T was non-motile and catalase-negative, but positive for alkaline phosphatase, β-glucosidase, and α-glucosidase. It hydrolyzed phenylphosphonate and reduced resazurin. 16S rRNA, groEL, gyrB, recA, and rpoB sequencing showed that HKU24T occupies a distinct phylogenetic position among the Leptotrichia species, being most closely related to Leptotrichia trevisanii. Using HKU24T groEL, gyrB, recA, and rpoB gene-specific primers, fragments of these genes were amplified from one of 20 oral specimens. Based on phenotypic and genotypic characteristics, we propose a new species, Leptotrichia hongkongensis sp. nov., to describe this bacterium. 相似文献
109.
距瓣尾囊草是我国特有的濒危物种,仅在涪江上游有分布。该文分析了距辫尾囊草(Urophysa rochkii)群落土壤水分、pH和氮素状况。结果表明:距瓣尾囊草群落pH值与水分含量呈显著正相关;pH值、水分与全氮呈显著负相关。距瓣尾囊草群落土壤理化性质受周围植被等因素影响较大。该文的研究结果为拯救这一种濒危植物提供了基础数据。 相似文献
110.
目的探究长期运动训练对青年男性淋巴细胞凋亡及线粒体DNA(mtDNA)修复酶(8-氧鸟嘌呤DNA糖基化酶,OGG1)的影响及可能机制。方法训练组为20名男子足球专业运动员,对照组为20名男子大学生。2组均在功率自行车上完成递增负荷力竭运动。运动前和运动后即刻采集静脉血。流式细胞法检测淋巴细胞凋亡率,比色法检测超氧阴离子和羟自由基含量和Caspase-3,Caspase-9活性,高效液相色谱法检测mtDNA中8-氧鸟嘌呤(8-oxodG)含量,Western-blotting法检测线粒体OGG1蛋白(mtOGG1)表达水平。结果运动前和运动后,训练组与对照组比较,超氧阴离子、羟自由基、Caspase-3,Caspase-9活性、8-oxodG降低,OGG1升高;运动后,训练组与对照组比较,淋巴细胞凋亡率降低。对照组和训练组在运动后与运动前比较,淋巴细胞凋亡率、超氧阴离子、羟自由基、Caspase-3,Caspase-9活性和8-oxodG均升高,但训练组升高幅度低于对照组;运动后对照组OGG1降低,而训练组OGG1升高。结论一次性力竭运动诱导产生高水平ROS,并抑制mtOGG1表达,使mtDNA氧化损伤,促进淋巴细胞凋亡;长期耐力训练可通过抑制ROS生成,并提高mtOGG1表达,抑制运动性淋巴细胞凋亡。 相似文献