禽类性别决定与分化相关基因的研究进展     

郑江霞  李显耀  杨宁 《中国畜牧杂志》2007,43(1):47-49

禽类的性别决定机制迄今尚无定论,目前较为公认的有以下几种假说:一是W染色体上携带性别决定基因(类似于哺乳动物的SRY)决定着个体的雌性化发育;二是Z染色体上某些基因的过表达(即不受剂量补偿效应限制)引发了个体的雄性化发育;三是前2种机制共同作用。已知禽类的性别决定候选基因有W染色体上的FET1、ASW和Z染色体上的DMRT1基因。此外,常染色体上的许多基因也参与禽类的性别决定和分化过程,如SOX9,AMH,cFOXL,CYP19A1等。  相似文献   

Diversity of grain proteins and bread wheat quality: I. Correlation between Gliadin Bands and Flour quality characteristics     

G. Branlard  M. Dardevet 《Journal of Cereal Science》1985,3(4):329-343

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化学镀Fe—Mo—W—B合金镀层的磁损耗     

王玲玲  周海萍 《湖南农业大学学报(自然科学版)》1997,24(4)

利用化学镀的方法制备了非晶态Ｆｅ－Ｍｏ－Ｗ－Ｂ四元合金镀层，利用Ｘ射线衍射方法屯镀层的结构，样品的磁损耗的由交流互感电桥原理测量，结果表明：具有较宽形成玻璃体能力的成分区域同时具有较低的磁损耗，与Ｆｅ－Ｍｏ－Ｂ非晶态合金镀层比较，Ｗ元素的加入并不明显改善镀层磁损耗，同时研究了样品在逐步退火过程中磁损耗随退火温度的变化规律。  相似文献   

Combination of serum phosphorylated neurofilament heavy subunit and hyperintensity of intramedullary T2W on magnetic resonance imaging provides better prognostic value of canine thoracolumbar intervertebral disc herniation     

Tadahisa MASHITA  Hiroaki KAMISHINA  Yuya NAKAMOTO  Yosuke AKAGI  Ataru NAKANISHI  Yusuke HARASAKI  Tsuyoshi OZAWA  Takashi UEMURA  Yui KOBATAKE  Shunsuke SHIMAMURA  Naoki KITAMURA  Sadatoshi MAEDA  Yuji UZUKA  Gerry SHAW  Jun YASUDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(4):433-438

The aim of this study was to evaluate the prognostic value of concurrent measurement of serum phosphorylated neurofilament heavy subunit (pNF-H) concentration and intramedullary T2W hyperintensity in paraplegic to paraplegic dogs. Our hypothesis was that concurrent measurement of these would provide a more accurate prediction of functional outcome in dogs with thoracolumbar intervertebral disc herniation (IVDH). A prospective case-control clinical study was designed using 94 dogs with acute onset of thoracolumbar IVDH. The association of serum pNF-H concentration, T2W hyperintensity on sagittal MRI (T2H/L2), deep pain perception and surgical outcome were evaluated with logistic regression analysis after three months for all 94 surgically treated dogs. Sensitivity to predict non-ambulatory outcome was compared among pNF-H and T2H/L2 and combination of both. Logistic regression analysis indicated that serum pNF-H concentration and T2H/L2 were significantly correlated with surgical outcome (P<0.05); however, deep pain perception was not (P=0.41). The results of logistic regression analysis indicated that the odds ratios of unsuccessful long-term outcome were 2.6 for serum pNF-H concentration, 1.9 for T2H/L2 and 2.3 for deep pain sensation. The sensitivity and specificity to predict non-ambulatory outcome for using serum parameter pNF-H>2.6 ng/ml, using T2H/L2 value of>0.84 and using both serum pNF-H and T2H/L2, were 95% and 75.7%, 65% and 86.5%, and 90.0% and 97.5%, respectively. Therefore, combined measurements of serum pNF-H and T2H/L2 might be useful for predicting long-term outcome in dogs with thoracolumbar IVDH.  相似文献   

硬枝碱蓬HPLC指纹图谱建立及模式识别研究     

马涛  赵宇  韩占江 《塔里木大学学报》2014,(4):96-104

为了对硬枝碱蓬样品质量进行评价,采用高效液相色谱法对9个不同采集地的硬枝碱蓬样品进行测定,建立指纹图谱,并结合中药相似度软件和主成分分析法进行模式识别研究。结果表明,试验确定的最佳条件为:提取溶剂为100%甲醇,用量为15 m L,流速为1.0 m L/min,色谱进样时间为20 min,流动相为甲醇(A)-水(B),采用100%甲醇等度洗脱,检测波长为254 nm。精密度试验、重现性试验、稳定性试验测定结果的相似度均在0.9以上,本研究所建立的基于主成分分析的模式识别方法准确可靠;中药相似度软件能够对不同地点的硬枝碱蓬材料进行区分,不同产地硬枝碱蓬的差异可清晰地显示出来。  相似文献   

用 1/N 展开法研究钨的能谱     

陈小林符力平  张庆营 《湖南农业大学学报(自然科学版)》2004,31(1)

用玻色子1／N展开技术研究了6个钨同位素的能谱和约化电磁跃迁概率B(E2)．结果表明，展开式的高阶项十分重要，6个核的能级能量的理论值和实验值的方均根差，最大的是154keV，最小的只有11keV，符合得令人满意．而且理论能正确地符合实验方面跃迁概率的“回弯”现象．  相似文献   

抗虫杂交棉W8225留叶枝栽培技术研究     

刘圣田  韩长胜  李泽田  朱兴胜  马德辉  吴丙娟  刘继永 《中国种业》2007,(9):44-45

抗虫杂交棉新品种W8225已通过山东省农作物品种审定委员会审定。为了适应留叶枝栽培棉区良种良法配套推广应用，最大限度地发挥优良品种的增产潜力，我们于2005-2006年开展了W8225留叶枝栽培技术研究。结果表明，W8225留叶枝栽培措施的最优组合方案为：每hm^2栽培密度27000株，施尿素525kg、磷酸二铵375kg、硫酸钾225kg，摘早蕾8个户蛛。  相似文献   

Application of low‐phosphorus‐containing legume residues reduces extractable phosphorus in a tropical Ultisol     

Eklou A. Somado  Ronald F. Kühne  Kanwar L. Sahrawat  Mathias Becker 《植物养料与土壤学杂志》2007,170(2):205-209

Application of legume green manure (GM) is suggested to be effective in increasing the availability of native soil phosphorus (P) and the dissolution and utilization of phosphate rock (PR)‐P by food crops. Experiments were conducted to study the dynamics of extractable P (P extracted by Bray‐1‐extracting solution) of an Ultisol amended with or without GM residues of contrasting P concentrations in the absence of growing plants. In two separate experiments, GM residues of Aschynomene afraspera (a flood‐tolerant legume) and of Crotalaria micans (upland) with varying P concentrations were added to an acidic soil amended with PR‐P or triple superphosphate (TSP) in plastic bottles. Soil moisture was brought to field capacity of the soil in the upland experiment and saturated with distilled water in the lowland setup. This was done to simulate aerobic upland and anaerobic lowland soil conditions in the relevant plastic bottles. Only P concentration of the residues added varied, while lignin and C : N ratios were similar. A temperature of 25°C was maintained throughout the experiment. Changes in soil extractable Bray‐1‐P were measured at the end of the incubation period (60 or 80 d). In the aerobic soils, extractable P in the combined PR+GM or TSP+GM treatments was significantly lower than in the PR‐ or TSP‐ treated soils. The amendment with GM residues alone significantly increased Bray‐1‐P over the unamended control in the case of the inorganic P‐fertilized GM residues. The trend in extractable P was similar in the soils incubated under anaerobic conditions. However, in the case of PR, concentrations of P extracted by Bray‐1 solution did not significantly change in the presence or absence of GM. The results suggest that the incorporation of GM residues with low P concentration does not lead to a net P release in upland or lowland soils. These results have implications for nutrient cycling in farming systems in W Africa as most of the soils are poor and very low in available P.  相似文献   

牛心朴子草对烟草病毒病的防效试验   总被引：1，自引：0，他引：1  

周德海  宋玉川  王玉军  朱常香 《山东农业科学》2007,(6):76-78

采用室内枯斑寄主法和田间生测试验,测定了植物源Antofine抗病毒水剂——牛心朴子草W制剂对烟草病毒病的防治效果。室内测定结果显示:将牛心朴子草W制剂与病毒汁液混合后接种,对病毒的抑制效果为70%~80%;先喷制剂,24 h后再接种病毒,对病毒抑制效果为40%~50%;先接种病毒,2 h后再喷制剂,基本无抑制效果。田间对烟草病毒病的防治效果显示:牛心朴子草W制剂对PVY、CMV和TMV的综合防治效果为40%~50%,与目前生产上用的常规药剂病毒必克和菌克毒克防效相近。  相似文献   

水仙在湖南引种栽培技术的研究Ⅰ．下种时期和覆盖对水仙生长发育的影响     

龙岳林  李筑荪  唐前瑞  刘丽辉  张宏志 《湖南农业大学学报(自然科学版)》1995,(3)

根据水仙生长发育对环境条件的要求，结合湖南长沙的气候特点，着重探讨了水仙下种时期和覆盖措施对叶片生长、水仙球的产量和质量的影响，结果表明：９月２５日下种，且在低温期间采用薄膜覆盖的效果最佳，其商品率和出口率分别达到了７８．０％和６３．４％．  相似文献