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对虾体内氯霉素含量测定方法的研究 总被引：1，自引：0，他引：1
应用ＨＰＬＣ技术建立常用药物氯霉素的虾体动力学研究方法。该方法的特点是：与微生物法、比色法、气相色谱法、荧光法及免疫法比较．测试准确、快速且灵敏度高。应用该方法可以从虾体内的血液、肌肉、肝胰脏、肠胃中分离出被虾吸收的氯霉素，并定量测定。在１—５０μｇ／ｍｌ范围内线性关系相关系数为０．９９９５。 相似文献
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Broodstock of Verasper moseri (Jordan and Gilbert) aged 3–4 years old were selected, and reinforced cultivation was conducted to promote maturation under
controlled water temperature and photoperiod conditions. Fertilized eggs were obtained by artificial fertilization, and the
development of embryos, larvae and juveniles was observed continuously. The results showed that the fertilized eggs of V. moseri were spherical, with transparent yolk and homogeneous bioplasm, and had no oil globule inside. The average diameter of the
eggs was 1.77±0.02 mm. The eggs of V. moseri were buoyant in water with salinity above 35. The cleavage type was typical discoidal. Young pigment cells appeared when
olfactory plates began to form. Hatching occurred at 187 h after fertilization at a water temperature of 8.5°C. The newly
hatched larvae, floating on the water surface, were transparent with an average total length of 4.69±0.15 mm. During the cultivation
period, when the water temperature was raised from 9 to 14.5°C, 4-day old larvae showed more melanophores on the body surface,
making the larvae gray in color. The pectoral fins began to develop, which enabled the larvae to swim horizontally and in
a lively manner. On days 7–8, the digestive duct formed. The yolk sac was small and black. The yolk sac was absorbed on day
11. Larvae took food actively, and body length and body height clearly increased. The rudiments of dorsal and anal fin pterygiophores
were discernible and caudal fin ray elements formed on day 19. On day 24, the larval notochord flexed upwards, and the rays
of unpaired fins began to differentiate. Pigment cells converged on the dorsal and anal fin rays, and the mastoid teeth on
the mandible appeared. On day 29, the left eyes of juveniles began to move upwards. Depigmentation began in some juveniles
and they became sandy brown in color on day 37. Most juveniles began to settle on the bottom of the tank. The left eyes of
juveniles migrated completely to the right side on day 50, when the average body length attained 2.5±0.18 cm, and juveniles
accomplished metamorphosis to young. The embryonic and larval characters of several flounder species are compared. 相似文献
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紫色土坡面降雨侵蚀试验研究 总被引：9，自引：0，他引：9
坡面水蚀的主要侵蚀动力来自降雨及其产生的地表径流,将坡面水蚀过程分为降雨侵蚀和径流侵蚀,可以从侵蚀动力、侵蚀特征差异与侵蚀规律等方面研究坡面水蚀过程与机理。应用人工模拟降雨及微小区测定技术,以大田紫色土为研究对象,模拟和测定不同雨强与不同坡度条件下降雨侵蚀过程和侵蚀量,揭示以降雨为主要动力的土壤降雨侵蚀特征和规律。研究结果表明：(1)小雨强(＜67．26 mm/h)下,紫色土坡面降雨侵蚀率具有稳定性,随着降雨历时的增加变化微小；大雨强(106．57 mm/h)下,降雨侵蚀率随降雨历时增加呈上下波动；(2)紫色土降雨侵蚀率与降雨强度呈线性相关,随降雨强度增加而直线增加；(3)降雨侵蚀率与坡度符合二次抛物线关系,随坡度的增加出现临界坡度,且临界坡度随雨强的变化而改变。在中小雨强(18．06～67．26 mm/h)条件下,临界坡度SK的变化范围在17°～19°。在大雨强条件下,临界坡度有逐渐增大的趋势；(4)当坡度与雨强共同影响产沙效应时,坡度对降雨侵蚀的影响较小,雨强能掩盖坡度对产沙的贡献。 相似文献
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Gracilaria asiatica,being highly efficient in nutrient absorption,is cultivated in sea cucumber ponds to remove nutrients such as nitrogen and phosphate.It was cultured in a laboratory simulating field conditions,and its nutrient absorption was measured to evaluate effects of environmental conditions.Ammonia nitrogen(AN),nitrate nitrogen(NN),total inorganic nitrogen(TIN),and soluble reactive phosphorus(SRP) uptake rate and removal efficiency were determined in a 4×2 factorial design experiment in water temperatures(T) at 15℃ and 25℃,algae biomass(AB) at 0.5 g/L and 1.0 g/L,total inorganic nitrogen(TIN) at 30 μmol/L and 60 μmol/L,and soluble reactive phosphorus(SRP) at 3 and 6 μmol/L.AB and ambient TIN or SRP levels significantly affected uptake rate and removal efficiency of AN,NN,TIN,and SRP(P<0.001).G.asiatica in AB of 0.5 g/L showed higher uptake rate and lower removal efficiency relative to that with AB of 1.0 g/L.Nitrogen and phosphorus uptake rate rose with increasing ambient nutrient concentrations;nutrient removal efficiency decreased at higher environmental nutrient concentrations.The algae preferred to absorb AN to NN.Uptake rates of AN,NN,and SRP were significantly affected by temperature(P<0.001);uptake rate was higher for the 25℃ group than for the 15℃ group at the initial experiment stage.Only the removal efficiency of AN and SRP showed a significant difference between the two temperature groups(P<0.01).The four factors had significant interactive effects on absorption of N and P,implying that G.asiatica has great bioremedial potential in sea cucumber culture ponds. 相似文献
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王勇强 《华东地质学院学报》2004,27(3):260-264
软岩嵌岩桩作为一种基础形式，目前国内研究较少。文章探讨了国内外对本课题的一些研究，分析了侧阻力的激发机理，详尽地阐述了嵌岩段侧阻力的影响因素，并且讨论了侧阻力的计算公式，分析表明岩石的强度、桩岩界面的粗糙情况、岩石的模量、岩石的初始应力等都对侧阻力有影响。研究表明，嵌岩段侧阻力受桩表面的法向刚度所控制，嵌岩段的单位极限侧阻力受嵌岩比的影响不大，规范上的公式不完全适合软岩嵌岩桩。 相似文献
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为探究纳米锌在制备水产动物致病菌灭活疫苗应用中的可行性。本研究利用不同浓度的纳米锌水溶液在不同温度条件下对杀鲑气单胞菌(Aeromonas salmonicida)进行不同时长的孵育处理。研究显示,纳米锌对杀鲑气单胞菌的灭活效果与浓度、温度及孵育时间均呈现正相关性,在高浓度与高温条件下灭活菌体所需的时间短。检测了不同灭活条件下纳米锌对杀鲑气单胞菌菌体蛋白及免疫原性的影响,SDS-PAGE结果显示不同条件下纳米锌灭活的杀鲑气单胞菌菌体蛋白组成及丰度与正常菌体没有明显差异;而扫描电镜结果显示,在37℃条件下纳米锌会造成菌体结构破损并出现细菌碎片;ELISA检测结果4℃条件下各纳米锌浓度灭活组菌体抗原性均未受到显著性影响,然而在28℃条件下,200和400mg/L纳米锌灭活组菌体抗原性显著低于对照组,而在37℃条件下除50mg/L浓度组外,其它3个浓度灭活组抗原性均显著低于对照组。比较研究了100mg/L-28℃灭活组与甲醛灭活的全菌疫苗的免疫保护效果,结果显示纳米锌与甲醛灭活菌体免疫组鱼体的免疫保护率分别为86.2%与79.3%。利用鲤上皮瘤细胞对纳米锌的细胞毒性进行了检测,结果显示400mg/L浓度以下纳米锌对细胞的贴壁、生长及代谢均无明显影响。本研究结果说明纳米锌对杀鲑气单胞菌具有明显的灭活效果,且灭活的全菌疫苗表现出良好的免疫保护效果,而其对菌体的抑杀能力及损伤程度与温度和时间密切相关,本研究为纳米锌在水产全菌灭活疫苗的制备提供了基础。 相似文献
8.
Broodstock of Verasper moseri (Jordan and Gilbert) aged 3-4 years old were selected,and reinforced cultivation was conducted to promote maturation under controlled water temperature and photoperiod conditions.Fertilized eggs were obtained by artificial fertilization,and the development of embryos,larvae and juveniles was observed continuously.The results showed that the fertilized eggs of V.moseri were spherical,with transparent yolk and homogeneous bioplasm,and had no oil globule inside.The average diamete... 相似文献
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温度和体质量对仿刺参消化道排空时间和排便量的影响 总被引：1，自引：0，他引：1
实验测定了不同体质量的仿刺参(Apostichopus japonicus (Selenka))在不同温度条件下, 消化道的排空时间、排便量和排便率。按仿刺参体质量大小分设10 g ± 0.5 g、40 g ± 2.0 g 和70 g ± 3.5 g 三个体质量组, 以及6、9、12、15、18、21 ℃共6 个温度梯度。结果表明, 各体质量组仿刺参的排空时间均随温度的升高, 具有先增大后减小的趋势, 10 g ± 0.5 g 和40 g ± 2.0 g 组分别在12 和15 ℃时排空时间最长, 且在9～15℃时差异不显著(P＞0.05), 但显著大于其他温度组(P＜0.05), 70 g ± 3.5 g 组仿刺参在12 ℃时的排空时间达各组最大值36.4 h。在6、18 和21 ℃温度条件下, 仿刺参的排空时间随体质量的增大总体呈增长趋势, 各温度组仿刺参的排便量均随体质量的增大而增加。仿刺参的个体排便率随体质量的增加而增大, 而单位体质量排便率多数随体质量增大而减小。10 g ± 0.5 g 和40 g ± 2.0 g 组的排便率均在6 ℃时最高, 70 g ± 3.5 g 组在9 ℃时达最高, 然后降低。温度和体质量对仿刺参排空时间和排便量均有极显著的影响(P＜0.01), 二者的交互作用对排空时间的影响也是极为显著的(P＜0.01),但对排便量的影响不显著(P＞0.05)。 相似文献