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991.
为筛选在城市生活污水中生长快、产油高的微藻,从污水样品中分离出40株微藻,采用高通量方法(96孔板培养、尼罗红染色)从中筛选出一株优良藻株,经18S rRNA基因序列分析及形态学鉴定属于小球藻属(Chlorella)。污水培养7 d后,其油脂含量达31.21%,污水的TN、NH+4-N、TP和COD去除率分别为71.6%、98.2%、99.4%和78.8%。该藻株在污水处理与微藻生物能源生产耦合系统中具有潜在的应用前景。 相似文献
992.
High quality requirements are set on durum wheat (Triticum durum) from semolina mills and pasta producers. For the production of semolina and pasta with good cooking quality, high grain protein content and vitreosity is required. The dependency of vitreosity on protein content as well as its stability under the influence of humidity was not well investigated up to now. We (1) compared two methods to determine vitreosity, (2) investigated the relationship between vitreosity and protein content, (3) developed a method to analyze vitreosity under humidity, and (4) examined the relationship between protein content and agronomical as well as quality traits in durum wheat. The results showed that the formation of vitreous kernels greatly depends on the protein content. To evaluate the stability of vitreosity under the influence of humidity a new method was elaborated and employed to assess the durum germplasm under study. This revealed that vitreosity of a durum wheat variety depends on the potential to form vitreous kernels but also to maintain this vitreosity under the influence of humidity. Our results further show that protein content is a central trait in durum wheat that strongly influences important traits like grain yield, vitreosity, and b-value. 相似文献
993.
Lorena Caro-Corrales Jose Caro-Corrales Angel Valdez-Ortiz Jose Lopez-Valenzuela Hector Lopez-Moreno Daniel Coronado-Velazquez Emilio Hernandez-Ortiz Jose Rendon-Maldonado 《Journal of insect science (Online)》2015,15(1)
The Mexican fruit fly, Anastrepha ludens Loew (Diptera: Tephritidae), is one of the most harmful pests of mango causing direct damage by oviposition on the fruit pulp. Mango for export is subjected to hydrothermal treatment as a quarantine method for the control of this pest, but exposure to heat for long periods of time reduces considerably the quality and shelf-life of treated fruit. The aim of this work was to study morphological changes of third-instar larvae and adults of A. ludens after in vitro exposure to high temperature at sublethal times. A heating block system was used to expose larvae at 46.1°C for 19.6 and 12.9 min, producing 94.6 and 70% mortality, respectively. Treated larvae were processed for optical microscopy. A fraction of surviving treated larvae was separated into containers with artificial diet to allow development into adults. Adult sexual organs were dissected and processed for transmission electron microscopy analysis. Results showed that 94.6% of the treated larvae died at 46.1°C for 19.6 min and none of the surviving larvae eclosed to adulthood, as they developed as malformed puparia. For the in vitro treatment at 46.1°C during 12.9 min, 70% of the treated larvae died and only 3.75% reached the adult stage, but ultrastructural damage in the male testes and in the female ovaries was observed. Additionally, 11.1% of the adult flies from the in vitro treatment also showed wing malformation and were incapable of flying. The analysis showed that surviving flies were unable to reproduce. 相似文献
994.
Ovulation induction in jundiá (Rhamdia quelen,Heptapteridae) using carp pituitary extract or salmon GnRH analogue combined with dopamine receptor antagonists 下载免费PDF全文
István Ittzés Tamás Szabó Ernani Carlos Kronbauer Béla Urbányi 《Aquaculture Research》2015,46(12):2924-2928
Jundiá (Rhamdia quelen) is an important species for aquaculture in temperate and subtropical climates. In the present study, the results of different forms of GnRH analogue treatments on ovulation in jundiá have been compared with those from treatment with carp pituitary. Seven out of eight females ovulated in groups treated with carp pituitary (4.0 mg kg?1 BW) and Ovaprim (0.5 mL kg?1 BW). Injection with sGnRHa (10 μg kg?1 BW) combined with metoclopramide (20 mg kg?1 BW) caused a significantly lower rate of ovulation with three out of eight females responding. None of the fish injected with sGnRHa (10 μg kg?1 BW) alone ovulated. Mean PGSI [(weight of stripped egg mass/BW of the female before stripping) × 100] and mean fertilization rate values were high and similar between treatment groups. The obtained results indicate that in jundiá, there is a strong dopamine inhibitory tone on gonadotropin secretion. The gonadotropin releasing activity of sGnRHa can be potentiated by dopamine receptor antagonists and the combined treatment is effective in inducing ovulation. In this regard, domperidone proved to be more potent than metoclopramide. 相似文献
995.
研究不同酸碱性溶液浸泡、不同光照变化、不同低温冷冻、不同温度水浴和不同时间超声波处理对‘伯乐一号’黄瓜种子萌发的影响。采用双层滤纸培养法对处理后的种子进行培养,观察记录种子的发芽势、发芽率和发芽指数,并对数据进行统计分析。实验显示,pH 9碱性溶液浸泡、持续黑暗处理、 48 h冷冻处理、30℃水浴处理和20 min超声波处理均可以提高‘伯乐一号’黄瓜种子发芽率;其中以48 h冷冻处理的‘伯乐一号’黄瓜种子发芽率最高,达到89.33%。总结出‘伯乐一号’黄瓜种子萌发的最适处理方法,对生产实践中有效促进其种子萌发及人工栽培具有重要的指导意义。 相似文献
996.
997.
2013年7月,陕西省汉中某大鲵养殖场发生以大鲵体表和四肢多处溃烂并伴有出血为特征的疾病,染病大鲵大量死亡。经临床观察、病理解剖及实验室检测,最后确诊病原为大鲵虹彩病毒。通过采取综合防治措施,养殖场大鲵疫情得到有效控制。 相似文献
998.
为对送检的发病藏香猪病死因进行确诊,本试验采用常规PCR、RT-PCR及荧光定量PCR方法,并结合流行病学调查、临床诊断及病理剖检等实验室检测对送检病料进行诊断,结果显示病死猪心脏、肺脏充血出血,肺脏肉变,气管内充满白色泡沫,全身淋巴结出血;荧光定量PCR方法检测猪圆环病毒呈阳性,PCR方法检出猪伪狂犬病病毒特异性条带,未见猪传染性胸膜肺炎放线杆菌、猪肺炎支原体条带,RT-PCR方法未扩增出猪瘟病毒、猪繁殖与呼吸综合征病毒特异性条带;血液涂片染色镜检可见猪附红细胞体。结果表明病死猪为猪伪狂犬病、猪圆环病毒病与猪附红细胞体病混合感染,采用经实验室诊断给出的综合防治方案治疗后,疫情得到控制。本次病例的诊治为养猪业可能发生的猪伪狂犬病、猪圆环病毒病、猪附红细胞体病的混合感染提供了有效的防治方法和借鉴经验。 相似文献
999.
[目的]研究不同温度处理对阿魏侧耳菌丝胞外酶活力和原基形成的影响,为生产中阿魏菇生长发育的调控和高效栽培提供参考依据.[方法]以阿魏侧耳(CGMCC 5.00774)为菌种,采用棉籽壳、麸皮、玉米粉为培养料培养菌丝至生理成熟,分别进行5、10和15℃低温处理(对照处理25℃),于第5、10、15、20、25和30d取样测定培养料中菌丝羧甲基纤维素酶(CMC酶)、半纤维素酶(HC酶)、淀粉酶、漆酶、蛋白酶的活力,观察各处理原基形成情况.[结果]与对照组相比,5、10、15℃低温处理后CMC酶和HC酶活力降低,漆酶、淀粉酶、蛋白酶活力则一直高于对照组.5℃处理25和30 d及10℃处理25和30 d的样品出现原基,其他处理均未出现原基.[结论]低温处理能引起菌丝胞外酶活力的变化,阿魏侧耳原基分化的最适低温处理条件是10℃,25 d. 相似文献
1000.
为探讨预热处理对尾巨桉木材干缩性和材色的影响,分别在100℃饱和蒸汽和120℃过热蒸汽条件下对尾巨桉木材进行预热处理。对预热处理前后的尾巨桉木材进行干缩率及色度指数的测定,应用扫描电镜对预热处理后尾巨桉木材的微观构造进行分析。结果表明:1)100℃饱和蒸汽可以使尾巨桉的干缩性降低,材色无明显变化;120℃过热蒸汽处理使尾巨桉在干燥过程中出现较多缺陷,如皱缩、内裂等,但可以有效促使桉木颜色向珍贵树种颜色转变。2)经120℃过热蒸汽处理,尾巨桉木材导管中纹孔的内含物被部分排出,细胞被压扁,宏观尺寸发生变形,是导致尾巨桉出现干燥缺陷的主要原因。 相似文献