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91.
Hormonal asynchronies during oestrus, related to the presence of suprabasal plasma-progesterone (P4) concentrations and a delayed ovulation, interfere with the fertility of repeat-breeder heifers (RBH). Since tubal dysfunction can occur in connection with hormonal asynchronies and constrained availability of fertile spermatozoa at the time of ovulation, the present study tested the hypothesis that frequent sperm deposition from onset of oestrus to ovulation may improve pregnancy rates in RBH. Five RBH and five virgin heifers (VH; controls) were repeatedly artificially inseminated (AI) at 6 h intervals from onset of oestrus to spontaneous ovulation. Hormone analyses revealed suprabasal P4 concentrations and a delay in the occurrence of the luteinising hormone (LH) surge, but a normal cortisol profile in RBH. Compared with controls, RBH presented longer interval from onset of oestrus to ovulation, and therefore, received more AIs. Pregnancy rates in RBH reached control levels (60%; NS), indicating that the hypothesis might be correct. Pregnancy rates in VH were below the expected range, presumably attributed to a deleterious influence of the frequent handling. The study suggests that pregnancy rates can be improved in RBH by frequent AI in relation to spontaneous ovulation. However, this practice of repeated manipulations, while seeming not to show adverse effects, lacks practicality for routine use.  相似文献   
92.
阿魏蘑、白灵菇及杏鲍菇亲缘关系的研究   总被引:6,自引:0,他引:6  
利用PCR产物克隆测序测定了阿魏蘑、白灵菇与杏鲍菇rDNA内转录间隔区(ITS)的序列,并对所测序列进行分析.结果表明,阿魏蘑、白灵菇和杏鲍菇三者之间具有较近的亲缘关系,白灵菇与杏鲍菇具有非常近的亲缘关系,但阿魏蘑、白灵菇和杏鲍菇为3个不同的种.  相似文献   
93.
杨桃果实生长发育过程中营养品质的变化   总被引:8,自引:0,他引:8  
杨桃(Averrhoa arambola L.)为华南地区重要的热带水果。本试材为华南农业大学园艺分场种植的3年生盆栽马来西亚甜杨桃,砧木为酸杨桃。在杨桃的开花期,选择生长势、开花数量和时间较一致45株为试材,再选择受精时间一致的果实做标记。采样时问从开花后(2003年7月15日)至杨桃充分成熟(2003年10月25)。测定杨桃果实中的糖(蒽酮比色法)、有机酸(HPLC法)、维生素C(2,6-二氯靛酚钠滴定法)和单宁(高锰酸钾滴定法)的含量。  相似文献   
94.
《动物防疫法》自1998年1月1日实施至今已有7年了,其在加强动物防疫工作的管理及预防、控制和扑灭动物疫病,促进养殖业发展,保护人体健康方面发挥了积极的作用。但在实际工作中,我们常常感到《动物防疫法》中的一些条款规定不明确、不具体,造成可操作性差,难以落实;同时一些罚则设置不当,处罚力度小,与相关法律衔接不上,起不到应有的作用。  相似文献   
95.
Five animals in a colony of cynomolgus monkeys (Macaca fascicularis) died or were euthanatized because of alveolar echinococcosis, during a period of 5 years. The remainder of the colony was screened for possible infection with Echinococcus multilocularis, using serology and ultrasonography. A total of 46 animals out of a group of 55 were examined. The presence of anti-Em2 antibodies analyzed with enzyme-linked immunosorbent assay was demonstrated in 3 monkeys. In 2 of these 3 monkeys, multilocular structures compatible with metacestodal cysts in the liver were identified, using ultrasonography. The presence of alveolar echinococcosis was subsequently confirmed at postmortem examination in 1 animal. The other animals are still alive. Two other monkeys were negative in the serological examination but had cystic structures in the liver, which were identified as bile duct cysts at postmortem examination in 1 animal. The other monkey is still alive. These findings suggest that serology for antibodies against the Em2 antigen may represent a useful method in identifying animals that might be infected with E. multilocularis and are therefore at risk of developing fatal alveolar echinococcosis.  相似文献   
96.
AIM:To explore the effect of brain ischemia injury on cell proliferation and nestin expression in cortex and subependymal zone (SEZ).METHODS:Using a local brain ischemia model(MCAO), BrdU positive cells of cortex and subependymal zone (SEZ), also nestin positive cells, were observed by immunohistochemistry.RESULTS:BrdU and nestin positive cells in SEZ of MCAO rats were obviously increased. In cortex, only nestin positive cells were observed.CONCLUSION:Neural stem cells in SEZ and cortex were activated after brain ischemia, it may be related with neural recovery after brain ischemia injury.  相似文献   
97.
汪俏梅  胡家恕 《园艺学报》2003,30(3):286-286
Glucoraphanin (4-甲基亚磺酰丁基芥子油苷 )在青花菜中含量丰富 ,其降解产物Sulforaphane具很强的抗癌活性。本试验以‘Marathon’青花菜为试材 ,将新鲜花球切成小花球后用 10 0mg/L的NaClO表面消毒 1min ,清水洗净。分别取 6 5 0g花球置于 0℃、 5℃和 10℃冷藏 ,并在 5℃下进行 5种气调处理 :1)Air,2 )Air+10 %CO2 ,3)Air+2 0 %CO2 ,4) 1%O2 ,5 ) 1%O2 +10 %CO2 。每一处理分别在处理当天、处理后 3、 6、 9、 12d取样 5 0g ,真空冷冻干燥 ,并研磨成粉末状贮藏于 4℃待用。将 0 .2g冷冻干燥样品在沸水中煮 10min ,35 0 0g离心 5m…  相似文献   
98.
优质高产菜豆新品种‘无筋2号''   总被引:2,自引:0,他引:2  
‘无筋2号’为优质高产菜豆新品种,生长势旺盛,耐肥抗倒,播种至采鲜荚生育期45d左右,结荚性好,豆荚饱满,商品性好,适宜速冻加工出口,鲜荚产量17—18t/hm^2,高产地块可达20t/hm^2以上。  相似文献   
99.
AIM:To investigate the role of expression of peroxisome proliferator-activated receptor α(PPAR α) in pathogenesis of rat fatty liver.METHODS:The rats were treated with a low dose of carbon terachloride (CCl4) and fed a high fat diet to produce fatty liver. We determined the concentrations of triglyceride (TG), total cholesterol (TC), free fatty acid (FFA) in liver and the alanine aminotransferase (ALT) activity, tumor necrosis factor-α (TNF-α), FFA in serum and the degree of hepatocytic steatosis. Total RNA of liver was extracted, and the expression of PPAR α were analyzed by semi-quantitative RT-PCR method.RESULTS:In model group, the hepatocytic PPAR α mRNA expression decreased to 0.41±0.28, compared to 1.41±0.29 in the control group (P<0.01). The contents of TG, TC, FFA in model rat liver were (1.88±0.20) mmol·L-1, (11.03±1.12) mmol·L-1 and (1 260.38±151.27) μmol·L-1, respectively, compared to (0.53±0.10) mmol·L-1, (1.25±0.25) mmol·L-1 and (334.30±27.09) μmol·L-1 in the control group (P<0.01). The activity of ALT, concentrations of TNF-α and FFA in serum were also increased remarkably in model group.CONCLUSION:Oxidation of fatty acid and utilization of lipids in liver are affected by reducing the expression of PPAR α, which result lipid accumulation in liver.  相似文献   
100.
该文通过分析巴旦杏在甘肃河西地区引种培育过程中出现的问题,总结出用容器育苗和大田开沟点播相结合来培育接穗,以山桃为砧木嫁接巴旦杏的引种驯化技术.结果表明,容器培育接穗比直接大田点播出苗率、成活率分别提高了10%和15%;巴旦杏与山桃嫁接表现出极好的亲和性,嫁接成活率为90%.  相似文献   
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