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331.
甘蔗ADP/ATP转运蛋白酶基因克隆及其序列的生物信息学分析 总被引:2,自引:1,他引:1
摘要:【研究目的】甘蔗(Saccharum officinarum Linn) 是C4光合途径作物,有着特殊的能量代谢系统,研究其能量代谢过程的ADP/ATP转运蛋白酶基因具有重要的意义。【方法】本研究采用同源克隆原理和PCR技术克隆甘蔗AAC转运蛋白酶基因,并应用生物信息学方法,对其进行多序列比对分析、物理性质分析、三级结构预测、亚细胞定位、跨膜区域预测和疏水性分析。【结果】克隆获得甘蔗AAC cDNA序列全长为1170bp,包括一个可编码387氨基酸的完整ORF。生物信息学分析显示,AAC家族基因的N端序列相对不保守,C端序列高度保守;其的分子量是42.265 kD,理论等电点是9.79,预测其为稳定的蛋白;GRAVY值为-0.099;含有6个跨膜区域;其6个跨膜螺旋(TM1-TM6)跨越磷脂双分子层结构,盐桥可能是通过中间的3个连接螺旋α1-α3共同构成的;定位在细胞质的概率为60.9%。【结论】本研究获得甘蔗AAC 完整ORF序列,并通过生物信息学预测该基因所编码的蛋白为一个稳定跨膜蛋白,其可能定位在细胞质。这些研究为甘蔗AAC基因的深入研究和应用奠定初步基础。 相似文献
332.
莱克多巴胺人工抗原的合成与鉴定 总被引:8,自引:0,他引:8
用戊二酸酐将盐酸莱克多巴胺活化成莱克多巴胺-戊二酸酐半醛,用混合酸酐法将莱克多巴胺-戊二酸酐半醛与KLH和BSA偶联,合成免疫原和包被抗原,经核磁共振法和紫外吸收法鉴定,偶联成功.用紫外吸收法测定免疫原和包被抗原的偶联比分别为24:1和2.5:1.用免疫原免疫新西兰白兔,采用间接ELISA法检测抗体效价,采用间接竞争ELISA法检测IC50值,获得了效价为1:6 000以上、IC50值为10 ng/mL的多克隆抗体,证明合成的人工免疫原具有免疫原性. 相似文献
333.
刘奎 《四川畜牧兽医学院学报》2007,5(5):183-186
大学生思想政治教育文化载体建设研究是近几年来我国思想政治教育学载体理论研究中涌现出的崭新课题之一。大学生思想政治教育文化载体是思想政治教育学载体理论的重要组成部分。研究大学生思想政治教育文化载体建设是对大学生思想政治教育载体理论的进一步深化和拓展。文中在分析大学生思想政治教育文化载体建设存在的问题及原因基础上。提出加强大学生思想政治教育文化载体建设的对策。 相似文献
334.
Ali Akbar MASOUDI Kazuyuki UCHIDA Kou YOKOUCHI Keiko MIYADERA Hiroyuki OGAWA Yoshikazu SUGIMOTO Tetsuo KUNIEDA 《Animal Science Journal》2007,78(6):672-675
Forelimb‐girdle muscular anomaly is a hereditary disorder of Japanese Black cattle characterized by tremors and astasia caused by hypoplasia of the forelimb‐girdle muscles. The locus responsible for this disorder has been mapped on a middle region of bovine chromosome 26. In this study, we applied marker‐assisted selection to identify the carriers of this disorder. Four microsatellite markers, DIK4440, BM4505, MOK2602 and IDVGA‐59, linked to the disorder locus were genotyped in 37 unaffected offspring of a carrier sire. Transmission of the mutant or wild‐type allele of the disorder locus of the sire to the 37 offspring was determined by examining the haplotypes of these markers. The results showed that nine and 18 of the 37 animals possessed the paternally transmitted mutant and wild‐type alleles, respectively, and therefore, the nine animals with the mutant allele were identified as carriers. We concluded that the marker‐assisted selection using these four markers can be applied for the identification of the carriers of forelimb‐girdle muscular anomaly of Japanese Black cattle. 相似文献
335.
Bernd Driessen DVM Dr. med. vet. DACVA ECVPT Benjamin Brainard VMD 《Journal of Veterinary Emergency and Critical Care》2006,16(4):276-299
Objective: To review the rationale behind and experiences with traditional and newly evolving concepts of fluid therapy in the traumatized patient, and to review conventional and novel fluid preparations for use in trauma resuscitation. Data sources: Human and veterinary clinical and research studies. Human data synthesis: Current treatment guidelines recommend aggressive fluid resuscitation with lactated ringers solution (LRS) or saline as optimum management of hemorrhagic shock in trauma, regardless of whether bleeding is controlled or not. The rationale behind this strategy is to restore intravascular volume as rapidly as possible to ensure adequate vital organ perfusion. Recently, this strategy has been challenged, especially in patients with uncontrolled hemorrhage, as neither laboratory evidence nor clinical trials support this practice. Current research indicates that vigorous fluid infusion may exacerbate bleeding and cause severe hemodilution, both impairing resuscitation outcome. As a result, a new line of thinking is emerging that balances the risks and benefits of intravenous volume infusion by offering the clinician alternative treatment strategies and emphasizes continuous endpoint‐oriented monitoring. ‘Hypotensive’ or ‘hypovolemic’ resuscitation techniques as well as initial volume replacement with fluids other than LRS or saline (e.g., hypertonic saline [HTS], HTS with dextran 70 [HTS‐D]) have been introduced in human medical practice as additional options for treatment of victims of trauma under certain circumstances. Clinical studies evaluating the use of hemoglobin‐based oxygen carriers (HBOCs) in the trauma setting are underway and may soon lead to an expansion of the fluid arsenal available to the clinician for treatment of trauma patients. Veterinary data synthesis: Based on available animal data, neither strict guidelines nor a clear fluid preference for resuscitation of traumatic shock have been defined. Although systematic clinical trials are missing, combinations of crystalloid and colloid (natural or artificial) appear to be as effective for resuscitation as crystalloid alone. Judicious use of an HBOC (e.g., Oxyglobin®) as a substitute for blood/red blood cells may be recommended in situations where whole blood or pRBCs are not or not yet available. Conclusions: The search for optimal methods of fluid resuscitation in trauma is ongoing. At this point the best solution is a differentiated approach to fluid therapy, one that tailors type and volume of resuscitation solution(s) used to the type and severity of injury in an individual patient and uses monitoring of perfusion and oxygenation parameters to guide resuscitation. Crystalloid fluids are effective for resuscitation but may need to be combined with or replaced by colloidal fluids in certain clinical situations. 相似文献
336.
Jahr JS Driessen B Lurie F Tang Z Louie RF Kost G 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2001,30(1):39-45
Abstract: This study was designed to validate in vitro oxygen saturation (SO2 ) measurements with the NOVA CO-Oximeter (Nova Biomedical Corp, Waltham, Mass, USA) in canine blood containing hemoglobin (Hb) glutamer-200 bovine (Hb-200; Oxyglobin, Biopure, Cambridge, Mass, USA) as a Hb-based oxygen carrier recently introduced into clinical practice. In the first set of experiments, stored blood from 6 mixed-breed canine blood donors was used. Target PO2 levels were reached in aliquots of blood samples by tonometry. Oxygen saturation was then measured with the test device and calculated based on known PO2 values. In the second set of experiments, total oxygen content was directly measured by means of an oxygen-specific electrode in aliquots of fresh whole arterial, venous, and mixed (arterial-venous) blood withdrawn from the same canine blood donors. Hb-200 was added to those blood samples to yield plasma Hb concentrations of 1.62, 3.25, 6.50, and 9.75 g/dL. Based on Hb content and SO2 measured by the NOVA CO-Oximeter in these samples, total oxygen content was also calculated for each sample and compared with measured values. A strong correlation was found between SO2 values measured with the co-oximeter in samples after tonometry, and calculated SO2 based on known PO2 . Directly measured total blood O2 content varied by ≤ 5% from values computed based on co-oximeter measurements of Hb content and SO2 . These results did not change with different levels of oxygenation of the samples or different plasma Hb-200 concentrations. In conclusion, the NOVA CO-Oximeter is an accurate analyzer for measurement of SO2 after Hb-200 administration to canine blood. 相似文献
337.
以木炭、泥炭、花土、有机肥、菌糠为不同基质载体,利用前期从植物根际分离出的3株溶磷菌和1株联合固氮菌制作PGPR菌肥,并进行田间随机区组试验,研究其对燕麦草产量和籽粒产量的影响。结果表明,除菌肥4以外,其余处理活菌数均符合《微生物肥料》NY227-94质量标准,其中,菌肥1和菌肥2的活菌数最优,适宜作为PGPR菌肥载体;施用不同PGPR菌肥对燕麦的株高、干草产量和籽粒产量具有明显的促进作用,其中,各处理对株高影响不显著,而燕麦草产量的增产效果与作物所处的生育期有关,灌浆期菌肥1的促生效果良好,成熟期菌肥5的促生效果较佳。菌肥1干草产量和籽粒产量较ck分别提高20.4%和10.8%,说明以配方1可作为PGPR菌肥的良好载体。 相似文献
338.
探讨鸡粪作为微生物肥料载体的可行性.以干燥或发酵处理的鸡粪为载体经辐照处理后,分别接种固氮菌、解磷巨大芽孢杆菌、硅酸盐细菌和枯草芽孢杆菌制作微生物肥料.以煤渣为载体设对照组,通过测定有效活菌数和杂菌率,优化鸡粪处理的最佳方法;从保存时间、温度、光照、pH值几个因素探讨微生物肥料的稳定性.结果表明,经堆肥腐熟并辐照处理的鸡粪作载体效果最佳,固氮菌肥和硅酸盐细菌肥料的保质期在6个月,磷菌肥和枯草杆菌肥的保质期在9个月;阳光直射处保存3个月的菌肥有效活菌数低,杂菌率高,而室内暗处保存的活菌数高,杂菌率低;菌肥的保存温度超过30℃时,有效活菌数急剧下降,杂菌率上升;将菌肥的pH值调至7时,有利于提高有效活菌数.可见鸡粪可用作微生物肥料的载体,保存在避光阴凉干燥处可有效提高菌肥的有效活菌数,从而延长产品的保存期. 相似文献
339.
340.
以海藻酸钠和壳聚糖为原料,合成了固定化微生物载体材料,对海藻酸钠含量、壳聚糖含量、固化时间、覆膜时间等对载体硬度的影响进行了研究,并将其作为固定化啤酒酵母(Saccharomyces cerevisiae)的载体应用于麦汁发酵,探讨了上述4种因素对外观发酵度的影响.结果表明,随着海藻酸钠、壳聚糖质量分数的增加和固化时间、覆膜时间的延长,载体硬度逐渐增加,当海藻酸钠质量分数为1.0%、壳聚糖质量分数为0.8%、固化时间为3 h、覆膜时间为10 m in时,其外观发酵度最高. 相似文献