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991.
提高森林质量是江西省林业建设攻坚战   总被引:1,自引:1,他引:0  
江西省林业提出“一个提高,两个调整,三个搞活”的施政方针,是三句话,六个字(提高、调整、搞活)组成的相互联系的一个整体,江西省林业建设现实中质量不高,结构不优、林业不活是个老大难问题,并集中表现在质量上,是计划经济与传统林业留下的后遗症.所以提高森林质量是林业建设攻坚战,是发展江西林业生产力的壮举,认真贯彻科教兴国发展战略,加大林业科教技投入,提高人材素质,选贤用能,组建一支精兵强将,夺取这一战役的辉煌胜利.  相似文献   
992.
针对汽车产品投资的特殊不确定性和其投资数额大、分阶段投入的状况,应用产品生命周期理论判定汽车产品项目的投资阶段,进而获得准确的阶段投资决策点,据此构建了基于汽车产品生命周期的汽车产品投资阶段判定和汽车企业投资决策点识别模型,并就影响识别的因素、阶段、模型进行数学表述,就汽车产品投资决策点抉择问题提出了解决的思路和方法.  相似文献   
993.
奶牛秸秆型日粮矿物质营养水平评价   总被引:2,自引:0,他引:2  
对淄博地区奶牛营养两次调查过程中,发现秸杆型日粮饲喂的奶牛可能存在矿物质缺乏问题。针对这一问题,测定日粮中钙、磷、铜、锰、铁、锌和奶牛血液中铜、锰、铁、锌元素的浓度,用以评价秸杆型日粮奶牛矿物质营养水平。结果表明:①秸杆型日粮存在矿物质营养不平衡问题,锰、锌元素不足,铁元素过剩。②秸杆型日粮矿物质营养具有互补作用。③评价奶牛矿物质营养水平的手段有待改进。  相似文献   
994.
模拟比较了随机选择、标记值选择及BLUP选择3种背景选择方法在标记辅助导入(利用标记辅助将供体群中的一个有利QTL等位基因导入到受体群中)的选择效果。前景选择是借助与目标基因连锁的两侧标记对目标基因进行间接选择。研究结果表明,在背景选择中,利用标记值选择能使受体基因组很快得到恢复,2个世代的回交就能恢复90%以上,4个世代的回交就能完全恢复。利用BLUP选择虽然不能使受体基因组迅速全部恢复,但能使特定的背景性状得到最大的遗传进展。  相似文献   
995.
A 45-day growth trial was conducted to investigate the effects of 4 concentrations (0, 40, 80, 120 mg·kg^-1 Zinc- Methionine (Zn-Met) supplementation on growth and serum biochemical indexes of Jirong rabbits (60-day-old). A total of 72 Jirong rabbits were randomly divided into 4 groups, 3 replicates with 6 rabbits each. The Met value in the basal diet was 0.60%. ADGs of group Ⅱ, Ⅲ and Ⅳ were significantly different than that of control, increased by 3.16%, 7.53%, 8.14% during 0-15 days and 7.58%, 15.60%, 15.71% during 16-30 days and 8.27%, 12.43%, 11.44% during 31-45 days (P〈0.05), but it was not significantly different in ADG among group Ⅱ, Ⅲ and Ⅳ (P〉0.05). The fur area and the density of hair of groups Ⅱ, Ⅲ and Ⅳ were not significantly different than that of control (P〉0.05). The content of serum zinc, AKP, ALB for groups Ⅱ, Ⅲ and Ⅳ were significantly different than that of control (P〈0.05). The serum TP and SUN in group Ⅱ, Ⅲ and IV were not significantly different than that of control (P〉0.05). The results show that dietary supplementation of Zn-Met is much more efficient than dietary without Zn-Met for 60-day-old Jirong rabbits.  相似文献   
996.
The study was conducted to investigate the effects of active immunization against myostatin on the titer of myostatin antibody, carcass evaluation, activity of creatine kinase and the expression of the myostatin gene in pigs. Eighteen pigs were allotted into three groups (six pigs per group), and pigs in treatment 1, 2 and 3 were immunized with physiological saline, 1 mg or 4 mg myostatin per pig, respectively. Six pigs were killed by electrical stunning followed by exsanguination at BW of 100 kg. The results indicated that the titer of myostatin antibody was increased in treated groups compared to the control group on day 42 ( P  < 0.01) and d 84 ( P  < 0.01). The carcass lean percentage was significantly increased in the treatment groups compared to the control group ( P  < 0.01), and intramuscular fat was significantly decreased in the 4 mg group compared to the control group ( P  < 0.05). The muscle creatine kinase activity of pigs treated with 1 mg and 4 mg myostatin was lower than the control group. The immunization of myostatin signofocantly decreased the myostatin gene expression levels in muscle. It was concluded that optimal active immunization against myostatin could increase the content of myostatin antibody, suppress the activity of creatine kinase and the expression of myostatin gene, and therefore improve the carcass lean percentage for pigs.  相似文献   
997.
利用FC-空间中的有关FCB-映象和FCs-优化映象的极大元存在性定理,在乘积FC-空间中建立和证明了几个有较好容许性质的FCB-映象组和FCB-优化映象组的极大元存在性定理.  相似文献   
998.
玉米地膜育苗定向栽培技术能增产1 575 kg/hm2,增收2 076元/hm2,解决了玉米一播全苗的问题.通过试验和示范,形成了集成技术体系,为大面积推广提供了技术支撑.  相似文献   
999.
AIM: To investigate whether gold nanoparticles (GNPs) reverses adriamycin (ADM), resistance of human hepatocellular carcinoma drug-resistant cell line HepG2/ADM and to explore the potential mechanism. METHODS: The sensitivities of HepG2 cells and HepG2/ADM cells to ADM were tested by MTT assay before and after GNPs pretreatment. The apoptotic rate was examined by flow cytometry. The concentration of ADM in HepG2/ADM or HepG2 cells was determined by ultraviolet-visible spectrophotometer. The content of glutathione (GSH) in HepG2/ADM or HepG2 cells by DTNB method. RESULTS: The half maximal inhibitory concentrations (IC50) of ADM for HepG2/ADM cells were(29.46±1.73) mg/L and (15.18±0.85) mg/L before and after GNPs pretreatment,respectively. The IC50 of ADM for HepG2 cells was (9.16±2.03) mg/L before pretreatment. The apoptotic rate in GNPs+ADM group was higher than that in ADM group (P<0.05). The concentration of ADM in HepG2/ADM group was lower than that in HepG2 group (P<0.01). After GNPs pretreatment, the concentration of ADM in HepG2/ADM cells was higher than that before pretreatment. The content of GSH in HepG2/ADM group was higher than that in HepG2 group (P<0.01). After GNPs pretreatment, the content of GSH in the HepG2/ADM cells was lower than that before pretreatment. CONCLUSION: Gold nanoparticles can reverse ADM resistance of human hepatocellular carcinoma drug-resistant cell line HepG2/ADM, reduce the content of GSH and increase the concentration of ADM in HepG2/ADM cells.  相似文献   
1000.
AIM: To investigate the effect of rhynchophylline (Rhy) on blood pressure, cardiac hypertrophy and myocardial fibrosis in spontaneously hypertensive rats (SHR). METHODS: Spontaneously hypertensive rats were randomly divided into model group, high dose (10 mg·kg-1·d-1) and low dose (2.5 mg·kg-1·d-1) group of rhynchophylline, captopril group (17.5 mg·kg-1·d-1). Wistar-Kyoto rats were used as normal control. Respectively, systolic blood pressure was measured by tail cuff every 2 weeks. After 10 weeks, heart weight index and left ventricular weight index were calculated. The myocardial hydroxyproline and plasma angiotensin Ⅱ were detected. Moreover, basic myocardial histopathological changes and myocardial collagen fibres were observed by HE staining and Masson staining, respectively. The protein expression of TGF-β1 and Smad3 in the myocardium was measured by the methods of immunohistochemistry and Western blot. RESULTS: Compared with SHR model group, Rhy significantly reduced blood pressure (P<0.05), the levels of HYP in the myocardium (P<0.05) and the levels of AngⅡ in the plasma (P<0.01). The pathological damages of the myocardial tissues and collagen deposition were attenuated. The protein expression of TGF-β1 and Smad3 was significantly reduced by the treatment with Rhy (P<0.01). CONCLUSION: Rhynchophylline reduces blood pressure and adjusts to improve ventricular remodeling of SHR. The mechanism may be involved in the TGF-β1/Smad pathway and reducing AngⅡ content.  相似文献   
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