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1.
Development of new semen cryopreservation techniques improving sperm survival and ensuring availability of viable spermatozoa for a prolonged time‐period after AI is promising tools to reduce sensitivity of timing of AI and enhance overall fertility. The SpermVital® technology utilizes immobilization of bull spermatozoa in a solid network of alginate gel prior to freezing, which will provide a gradual release of spermatozoa after AI. The objective of this study was to compare post‐thaw sperm quality and in vitro sperm survival over time of Norwegian Red bull semen processed by the SpermVital® (SV) technology, the first commercialized production line of SpermVital® (C) and by conventional procedure applying Biladyl® extender (B). Post‐thaw sperm motility was not significantly different between SV, C and B semen (p > .05). However, sperm viability and acrosome intactness were higher for SV than C and B semen (p < .05). Small differences in DNA quality were observed (p < .05). Sperm viability after storage in uterus ex vivo was higher for SV than for C semen (p < .05). Furthermore, sperm survival in vitro over time at physiological temperature was significantly higher for SV semen than C semen as well as B semen during the incubation period of 48 hr (p < .05). In conclusion, the SpermVital® technology is improved and is more efficient in conserving post‐thaw sperm quality and results in higher sperm viability over time in vitro for SV than for C and B semen.  相似文献   
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土壤重金属钝化效果评估——基于大田试验的研究   总被引:4,自引:4,他引:0  
采用野外大田试验,研究了钙镁磷肥(Calcium-magnesia phosphate fertilizer)、麦饭石(Medical stone)、氧化铁吸附剂(Ferric oxide adsorbent)、氧化铝复合材料(Alumina composite)、植物型有机肥(Plant-based organic fertilizer)、牛粪(Cow dung)、骨炭(Bone char)对某地重金属污染农田的钝化修复效果,并利用动态加权评估方法评估了这几种钝化材料的综合适用性。试验结果表明:几种材料对土壤pH影响均较小,钙镁磷肥、麦饭石微量提高了土壤pH,与对照组相比分别增加0.68和0.74个单位;施加植物型有机肥、牛粪和骨炭提高了土壤有机质含量,与对照组相比分别增加了3.19、2.64 g·kg~(-1)和1.17 g·kg~(-1)(10.04%、8.31%和3.68%)。几种材料在0.6%的投加量下,除植物型有机肥外均有较好钝化效果,土壤有效态镉降低18%以上,且显著减少糙米中镉蓄积量(0.062~0.087mg·kg~(-1)),低于国家食品安全标准限值。为综合评估几种材料的效果及适用性,以土壤重金属有效态含量、糙米镉含量、修复成本和产量为指标构建动态加权函数综合评估模型,评估结果表明,钙镁磷肥的综合修复效果最好,其次为骨炭和植物型有机肥。  相似文献   
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The application of soil amendments to immobilize heavy metals is a promising technology to meet the requirements for environmentally sound and cost‐effective remediation. The present study was carried out to evaluate the result of phosphogypsum (PG) used alone and in combination with compost (CP) at a mix ratio of 1:1 wet weight ratio (PG + CP) at 10 and 20 g dry weight kg−1 dry soil, on heavy metal immobilization in contaminated soil and on canola growth. The results revealed that the Pb, Cd and Zn uptake of canola plants was reduced by the application of PG alone and when it was mixed with CP as compared with untreated soil. At an application rate of 10 g dry weight kg−1 dry soil of (PG + CP) the dry weight of canola plants increased by 66·8% was increased in comparison with its weight in the untreated soil. The addition of PG alone resulted in more pronounced immobilization of heavy metal as compared with PG mixed with CP. Plant growth was improved with CP addition, but heavy metals immobilization was the greatest in PG alone treatments. Results suggest that PG may be useful for the immobilization of heavy metals in contaminated soils. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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自从Piezo操作系统应用于显微操作代替了传统的机械注入方法以来,小鼠胞质内单精注射的成功率就大大提高了。单精注射(ICSI)的基本原理并不复杂,但是许多研究表明小鼠精子的质膜、顶体、制动时间均会对ICSI的结果造成影响。文章概述了小鼠单精注射的基本原理及小鼠精子质膜的完整性,顶体反应,制动时间与ICSI成功率之间的关系,以期在此基础上提出今后的研究方向,对于分析受精过程的发生,改进单精注射技术及进一步提高受精率,都具有重要的理论意义及实践价值。  相似文献   
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ObjectiveTo assess the sedative and immobilization effect of intranasal administration (INS) of midazolam (MID) without or with INS dexmedetomidine (DXM), and some physiological changes induced by the drugs. The ability of INS atipamezole to reverse the DXM component was also assessed.Study designProspective ‘blinded’ experimental study.AnimalsIn total, 15 pigeons.MethodsPigeons were sedated by INS MID alone at a dose of 5 mg kg−1 (group MID, n = 6) or in combination with INS DXM at a dose 80 μg kg−1 (group MID-DXM, n = 6). Measurements were made of heart rate (HR), respiratory rate (fR) and cloacal temperature (CT). The degree of sedation was assessed at 15 minutes prior to, immediately after, and at intervals until 100 minutes after drug administrations. Following MID-DXM, INS atipamezole (250 μg kg−1) was administered and the same indices measured 5 and 10 minutes later.ResultsMID had no effect on HR and fR, and although CT decreased, it remained within physiological range. MID-DXM caused significant falls in HR, fR and CT that persisted until the end of sedation. Atipamezole antagonized sedation and cardiorespiratory side effects of MID-DXM within 10 minutes of application. In addition, for MID compared to MID-DXM, the lowest sedation scores [10 (7–14) and 10.5 (5–14) versus 2 (1–4) and 2 (1–5)] were achieved in the 10th and 20th minute versus the 20th and 30th minute of the sedation, respectively.Conclusions and clinical relevanceMID alone, given INS had minimal side effects on vital functions but caused inadequate immobilization of pigeons for restraint in dorsal recumbency. MID-DXM caused an effective degree of immobilization from 20 to 30 minutes after administration, at which time birds tolerated postural changes without resistance. Atipamezole antagonized both side effects and sedation, but complete recovery had not occurred within 10 minutes after its application.  相似文献   
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ObjectiveTo study the effects of the addition of hyaluronidase (HA) to an etorphine/azaperone drug combination on induction times of immobilization.Study designExperimental part-randomized ‘blinded’ cross-over study.AnimalsEight wild managed blue wildebeest (Connochaetes taurinus).MethodsAnimals were immobilized, on separate occasions separated by two weeks, with one of four treatments. Treatments were; ‘Control drugs (CD), etorphine 0.01 mg kg−1 + azaperone at 0.1 mg kg−1; treatment 1 CD + 5000IU HA; treatment 2 CD + 7500 IU HA; and treatment 3 etorphine 0.007 mg kg−1 + azaperone at 0.07 mg kg−1 + 7500 IU HA. Times to first effect and to immobilization (from darting to possible to approach and blindfold) were measured. anova was used to compare treatments. Results are given in means ± SD (range).ResultsFor control, and treatments 1–3 respectively, times (in minutes) to first effect were 1.58 ± 0.42 (1.02–2.10), 1.64 ± 0.42 (0.95–2.17), 1.12 ± 0.24 (0.80–1.48) and 1.60 ± 0.21 (1.13–1.88) and to immobilization were 5.38 ± 1.53 (3.82–8.07), 3.80 ± 1.14 (2.02–5.50), 3.51 ± 1.08 (2.28–5.52) and 4.46 ± 0.67 (3.30–5.40). Compared to control, time to first effect for treatment 2 was significantly shorter. Time to immobilization was significantly quicker in all three treatments containing HA than that for control.Conclusion and clinical relevanceHyaluronidase can reduce the time to immobilization when used in the immobilizing dart, and might be usefully incorporated into etorphine combinations for darting wildlife.  相似文献   
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生物炭固定化微生物技术具有高效、成本低和环境友好性的优点,在土壤修复中展现出巨大的应用潜力,成为目前的研究热点。本文在系统总结国内外生物炭固定化微生物技术修复污染土壤的最新研究进展基础上,重点分析了生物炭作为载体的适宜性,探讨了微生物筛选的重要性,对比分析了固定化方法(如吸附法、包埋法、交联法和共价结合法等),探究了不同环境因素对生物炭固定化微生物技术修复污染土壤效果的影响,揭示了生物炭与微生物修复重金属和有机污染土壤过程中多种作用机制的协同效应,既包括生物炭作为固定化载体对微生物的保护及快速定殖作用,也包括生物炭对污染物的吸附作用,还包括微生物对污染物的降解作用。最后,对该技术在土壤污染修复中的应用提出了展望和建议。  相似文献   
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