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为提高海棠种子发芽率,以湖北海棠(Malus hupehensis)种子为研究对象,探讨了不同浓度GA3、磁场强度、温度及低温层积处理对湖北海棠种子萌发的影响。结果表明:(1)0.1%和0.05%浓度的GA3处理,播种后20d,湖北海常种子发芽率显著高于对照(P0.05),但各处理间差异不显著(P0.05),播种后30~40d,经0.1%GA3处理的种子发芽率显著高于0.05%GA3和对照组(P0.05),最高可达82.0%;(2)与对照组相比,磁场处理显著提高种子发芽率(P0.05),播种后20d,5 000GS处理的种子发芽率显著高于2 000GS和对照组(P0.05),最高可达92.5%,播种后30~40d,不同磁场强度处理的种子发芽率显著高于对照组(P0.05),最高达82.0%,但各处理间差异不显著(P0.05);(3)20℃和40℃温水浸泡24h处理后20~40d,种子发芽率显著高于对照组(P0.05),增幅最高达86.2%;(4)低温层积处理后30~60d,其发芽率显著高于对照组(P0.05),最高达41.7%。 相似文献
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根据不同类型岩浆岩的岩石密度、磁性的不同,通过应用RGIS软件和Surfer软件对重磁异常分离、延拓、求导及重、磁特征信息的复合处理等,研究了小秦岭岩浆岩地球物理特征,结果表明:重磁反映岩浆岩带所处的构造单元部位、岩浆系列特征以及与矿带的时空关系,由此可将小秦岭划分为4段不同的岩性岩浆岩。 相似文献
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乌鲁木齐城市土壤磁化率特征及其环境意义 总被引:1,自引:0,他引:1
对乌鲁木齐市区及其周边地区45个地点的土壤样本进行磁化率测定。结果表明,乌鲁木齐城市土壤磁化率大都处于中低值区域,具有空间差异性的特征,进而结合采集点的土壤环境状况分析了乌鲁木齐城市土壤的环境特征,探讨乌鲁木齐城市土壤磁化率表征下土壤污染的影响机制。 相似文献
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Bahram Falahatkar Konrad Dabrowski Murat Arslan & Jacques Rinchard 《Aquaculture Research》2006,37(8):834-841
This study was conducted to examine the effects of different forms and concentrations of ascorbic acid (vitamin C), and different enrichment times (24 and 48 h post ovulation) on egg, embryo and alevin ascorbate concentrations and survival of rainbow trout (enrichment was at the ova stage). In experiments 1 and 2, fertilized eggs were immersed in water containing ascorbate at 0 (control), 100, 1000 mg L?1 l ‐ascorbic acid (AA) and 2000 mg L?1 l ‐ascorbyl monophosphate (AP). In experiment 3, 0 (control), 500 and 1000 mg L?1 AA neutralized (N) with NaOH, 1000 mg L?1 AA non‐neutralized (NN), 1000 and 2000 mg L?1 AP immersions were used. The mean total ascorbic acid (TAA) and dehydroascorbic acid (DHA) concentrations were measured before fertilization, at 3 and 24 h after fertilization, at the eyed stage, and in hatched alevins. We observed significant differences in TAA concentration at different immersion levels at 3 and 24 h after fertilization. Survival decreased significantly depending on the level of vitamin C, pH of the solutions and immersion time. We suggest that when broodstock rainbow trout do not have enough vitamin C in their ovaries, immersion of eggs in 1000 mg L?1 of neutralized AA may be useful. 相似文献
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《Journal of Exotic Pet Medicine》2014,23(3):287-293
A 3-month-old intact female ferret (Mustela putorius furo) was presented with a 2-month history of ataxia. On physical examination, the ferret had difficulty standing upright. During the neurologic examination, the patient had a left head tilt and positional strabismus, circled to the left, and was ataxic. Results of the complete blood count were consistent with a mild normocytic normochromic anemia. Initial treatment was supportive. Magnetic resonance imaging was performed and revealed an asymmetry of the inner ears. A brainstem auditory evoked response test was also performed. History, clinical signs, and diagnostic test results indicated that the ferret was suffering from congenital peripheral vestibular syndrome and left-sided deafness. Congenital disease should be considered in the differential diagnosis of young ferrets with peripheral vestibular syndrome. Supportive care and physiotherapy can improve balance and motor function, leading to an acceptable quality of life. 相似文献
100.
《Journal of Veterinary Behavior: Clinical Applications and Research》2014,9(5):269-273
A 32-month-old female 225-kg nonpregnant cross-bred Newsham sow presented a 6-week history of stereotypic behaviors when housed in a laboratory research facility. A behavioral examination over 12 daylight hours revealed 3 main stereotypic motor patterns, namely (1) oral-nasal gate manipulation defined as placement of the snout between the bars of the pen gate with repetitive, forceful up and down movement; (2) head weaving defined as repetitive lateral head and snout movement toward the pen gates while rocking back and forth on her forequarters with hooves remaining on ground at all times; and (3) body weaving defined as repetitive shifting of body weight from one side to the other with front hooves lifting alternately off the ground. The sow performed the oral-nasal gate manipulation and head and body weaving 4.0%, 12.4%, and 6.8% of her total baseline time budget, respectively. The presumptive diagnosis was oral-nasal and locomotory stereotypies. Three treatments were used to mitigate the duration and frequency of these stereotypic behaviors. Treatment 1—Social treatment (change social stimuli by providing visual and nose-to-nose contact with different neighboring sows); Treatment 2—Forage treatment (change foraging substrates by providing peat moss as a rooting substrate); and Treatment 3—Space treatment (change pen configuration by increasing space). The sow performed the oral-nasal gate manipulation and head and body weaving 0%, 0.4%, and 0.1% of her total time budget, respectively; social treatment: the sow performed the oral-nasal gate manipulation and head and body weaving 0.9%, 15.3%, and 11.3% of her total time budget, respectively; and forage treatment: the sow performed the oral-nasal gate manipulation and head and body weaving 0.5%, 28.0%, and 15.5% of her total time budget, respectively. This study is one of the first reports to evaluate the treatment of established stereotypies in a mature sow. Results suggest the promise of environmental enrichment as an effective treatment strategy. Further research is needed to evaluate the persistence of these behavioral changes and relative importance of different environmental manipulations provided. 相似文献