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41.
影响波尔山羊超排效果的因素   总被引:4,自引:0,他引:4  
对204只(次)波尔山羊采用C IDR+FSH+PG法超数排卵(以下简称超排),发情配种后第6天采用手术法从子宫角采胚,采胚成功率为92.16%(188/204),头均获胚(16.68±7.89)枚,其中头均获可用胚(14.11±8.37)枚,可用胚率84.66%(2 654/3 135)。对不同国家产FSH、不同剂量FSH、注射LRH+P4、不同季节、重复超排、左右侧卵巢等因素对波尔山羊超排效果的影响进行了研究。结果表明,以日本和国产(动物所)FSH超排效果为佳,头均获可用胚分别为(15.66±8.26)枚(n=89)和(15.39±6.91)枚(n=23);日本产FSH 14~16 mL组效果最佳,头均获可用胚(19.63±8.96)枚(n=19);注射LRH+P4组头均获可用胚(16.04±8.84)枚(n=80),极显著高于对照组(12.16±7.68)枚(n=62);春季、秋季、冬季超排头均获可用胚分别为(10.86±5.10)枚(n=7)、(11.30±8.29)枚(n=23)、(11.00±6.17)枚(n=10),差异不显著;重复超排(间隔12月)第1次头均获可用胚(15.08±5.12)枚(n=26),第2次头均获可且胚(16.92±8.32)枚(n=26)。  相似文献   
42.
将18头荷斯坦产奶牛随机分为试验6组,每组3头,试验Ⅰ~Ⅵ组奶牛依次饲喂不同精粗料比(精料:粗料)的TMR1(20∶80)、TMR2(30∶70)、TMR3(40∶60)、TMR4(50∶50)、TMR5(60∶40)、TMR6(70∶30)的日粮,探讨不同精粗料比TMR对奶牛粪尿、N、P的排泄量和CH4释放量的影响。结果,饲喂TMR4与饲喂TMR1和TMR6的奶牛相比,每头奶牛每年CH4释放量减少15.20Kg和89.84Kg;粪便排泄量减少1.37t和1.41t;N降低3.71kg和17.50kg;P减少2.59kg和4.07kg,比TMR1FCM提高10.54%(P〈0.05);乳脂率增加9.67%(P〈0.05);乳糖增加7.26%(P〈0.05),能减少奶牛对土壤水源及空气的污染,提高奶牛的生态效益和经济效益。  相似文献   
43.
CD4分子为动物辅助性T细胞(TH)和部分胸腺细胞的共受体与信号传导分子,参与TCR介导的TH细胞活化和胸腺细胞分化过程。本研究应用RT-PCR和RACE技术从猪胸腺细胞总RNA中扩增克隆了猪CD4全长cDNA序列,并进行了序列特性分析。序列分析结果表明,在猪胸腺细胞和外周血淋巴细胞中存在2种方式剪接的CD4 mRNA转录本,其中一种mRNA转录本缺失编码40个氨基酸残基的120nt序列,提示该转录本可能编码猪分泌型CD4分子;猪CD4全长cDNA序列为2715nt。其中5′非编码区159nt,3′非编码区1183nt,1374nt的开放阅读框编码457个氨基酸的猪CD4前体蛋白(含4个糖基化住点);猪CD4分子的7个Cys残基(Cys^43、Cys^122、Cys^327、Cys^418、Cys^421、Cys^444和Cys^446)和2个Ser残基(Ser^432和Ser^439)在动物种间保守;在猪CD4分子胞浆区.存在高度保守的Src家族蛋白酪氨酸激酶p56^kk。识别位点KKTCQC和内化相关双亮氨酸基序。推导氨基酸序列分析结果显示,猪与人、免、猫、狗和鼠CD4蛋白的氨基酸同源性分别为56.0%,54.5%。56.9%,56.5%和44.9%。  相似文献   
44.
武玲萱  刘钊  王静 《中国蔬菜》2014,1(9):42-43
晋萝卜4 号是以雄性不育系4-01A 为母本,自交系03-37-1 为父本配制而成的秋冬萝卜一代杂种,生育期80 d(天)。地上部叶丛半直立,叶片稀疏,肉质根圆柱形,表皮光滑,出土部分皮绿色,入土部分皮白色,近1/2 露出地面。含水量适中,肉质甜脆,商品性好。肉质根纵径30 cm,横径7~8 cm,单根质量1.5 kg,每667 m2 产量5 000 kg 左右。适宜山西省及其周边地区种植。  相似文献   
45.
46.
MA Wei  YANG Jia-yao  AN Liu  ZOU Qi  ZHANG Xiao  LIU Nian 《园艺学报》2021,36(12):2258-2263
AIM To observe the effect of Fuzilizhong decoction on the inflammatory damage of non-alcoholic fatty liver disease (NAFLD) rats and to explore its mechanism. METHODS SPF male SD rats were randomly divided into 6 groups: control group, model group, high dose (20 mg·kg-1·d-1), middle dose (10 mg·kg-1·d-1), low dose (5 mg·kg-1·d-1) Fuzilizhong decoction group and Yishanfu (30 mg·kg-1·d-1)group, 8 rats in each group. A NAFLD rat modelwas established by intragastric administration of fat emulsion for 4 weeks. Then the drug was given for 4 weeks in each treatment group. HE staining was performed to observe the histopathological changes of the rat liver.The serum levels of interleukin-2(IL-2), IL-6 and tumor necrosis factor-α(TNF-α) were measured by ELISA. The expression of toll like receptor 4(TLR4) and NF-κB p65 in liver tissues at mRNA and protein levels was determined by RT-qPCR and Western bolt,respectively. RESULTS Compared with control group, the inflammatory damage of liver tissue was more serious, the serum levels of IL-2, IL-6 and TNF-α, the mRNA expression TLR4 and NF-κB p65 in liver tissues were significantly increased in model group(P<0.05). However, compared with model group, the liver pathological changes in each treatment group were significantly relieved, the serum levels of IL-2, IL-6 and TNF-α, the mRNA expression of TLR4 and NF-κB p65 in liver tissues were significantly reduced(P<0.05).In addition, the changes of TLR4 and p-NF-κB p65 protein levels in liver tissue were consistent with the changes of TLR4 and NF-κB p65 mRNA. CONCLUSION Fuzilizhong decoction attenuates the inflammatory damages of NAFLD in rats by inhibiting TLR4/NF-κB p65 signaling pathway.  相似文献   
47.
AIM To observe effects of emotional stimulation on expression of stromal cell-derived factor-1(SDF-1) and CXC chemokine receptor 4 (CXCR4) in plasma, platelets, aortas, hippocampus and bone marrow of apolipoprotein E gene knockout (ApoE-/-) mice, and to reveal the possible mechanism of the aggravated atherosclerotic plaque vulnerability by emotional stimulation. METHODS Thirty 8-week-old male ApoE-/- mice were randomly divided into normal control group, high fat group, and emotional stimulation group. Ten 8-week-old inbred C57BL/6J mice served as blank control group. After 12 weeks of intervention, the serum levels of SDF-1 and CXCR4 were investigated by ELISA. The protein levels of SDF-1 and CXCR4 in platelets, aortas, hippocampus and bone marrow were determined by Western blot. The pathological damage of aortas was observed by oil red O staining. RESULTS Compared with blank control group, normal control group and high fat group, the mice subjected to emotional stimulation showed more serious atherosclerosis in aortas detected by oil red O staining, and increased levels of SDF-1 and CXCR4 in the plasma and aortas were also observed (P<0.05). The results of Western blot showed that the protein levels of SDF-1 and CXCR4 in platelets, aortas and hippocampus were increased in the mice subjected emotional stimulation, but the expression of SDF-1 and CXCR4 in the bone marrow was decreased (P<0.05). CONCLUSION Imbalance of SDF-1/CXCR4 may be the key target by which emotional stimulation accelerates the progression of atherosclerosis.  相似文献   
48.
AIMTo investigate the roles of protein phosphatase 4 (PP4) in down-regulation of endothelial nitric oxide synthase (eNOS) Ser633 phosphorylation induced by palmitic acid (PA). METHODSHuman umbilical vein endothelial cells (HUVECs) were treated with PA at 25 μmol/L, 50 μmol/L, 100 μmol/L and 200μmol/L for 36 h, or treated with PA at 100 μmol/L for 12 h, 24 h, 36 h and 48 h. Protein phosphatase 2A (PP2A) family inhibitor fostriecin (FST, 20 nmol/L) or okadaic acid (OA, 5 nmol/L) was selected to pretreat the HUVECs for 30 min. Protein phosphatase 4 catalytic subunit (PP4c) siRNA or protein phosphatase 2A catalytic subunit (PP2Ac) siRNA was transfected into the HUVECs. The protein expression levels of of eNOS, PP4c and PP2Ac, as well as the level of eNOS Ser633 phosphorylation, were detected by Western blot. The intracellular nitric oxide (NO) content was measured by DAF-FM DA. RESULTS(1) Compared with control group, the levels of eNOS Ser633 phosphorylation were decreased in PA groups in which the HUVECs were treated with 25 μmol/L, 50 μmol/L, 100 μmol/L and 200 μmol/L PA for 36 h (P<0.05) and 100 μmol/L PA for 24 h, 36 h and 48 h (P<0.05). No significant difference in the level of total eNOS protein expression among all the groups was observed. (2) Compared with control group, both FST and OA pretreatment reversed the reduction of eNOS Ser633 phosphorylation (P<0.05) and the decrease in intracellular NO content (P<0.05) induced by PA. No significant difference in the level of total eNOS protein expression among all the groups was observed. (3) Compared with si-Control group, the PP4c protein expression was significantly reduced (P<0.05), while the level of eNOS Ser633 phosphorylation was significantly increased in si-PP4c group (P<0.05). Although the levels of PP2Ac protein expression declined significantly (P<0.05), the level of eNOS Ser633 phosphorylation remained unchanged in si-PP2Ac group. No significant differencein the level of total eNOS protein expression among all the groups was found. CONCLUSION PA significantly reduces the level of eNOS Ser633 phosphorylation and the content of NO in the HUVECs, which may be due to PA inducing the activation of the PP2A family member PP4 rather than PP2A.  相似文献   
49.
AIM To investigate the effect of sulodexide (SDX) on high glucose-induced damage in retinal microvascular endothelial cells. METHODS (1) High-fat diet combined with intraperitoneal injection of streptozocin were used to induce type 2 diabetes mellitus (DM) followed by injection of saline or SDX in C57BL/6J male mice. Retinal microvascular leakage and density, and the protein levels of NLRP3 inflammasome-related proteins, zonula occludens-1 (ZO-1) and NADPH oxidase 4 (NOX4) were measured. (2) Human retinal microvascular endothelial cells (HRMECs) were treated with normal glucose or high glucose with or without SDX, and were further transfected with siRNA to knock down NOX4, or infected by adenovirus to over-express NOX4. The protein levels of ZO-1, VE-cadherin (VE-Cad), NOX4 and NLRP3 inflammasome-related proteins as well as the level of reactive oxygen species (ROS) were detected. RESULTS Treatment with SDX increased the protein level of ZO-1, attenuated retinal leakage and NLRP3 inflammasome activation, and enhanced the density of microvasculature and the number of ganglion cells in diabetic retinas. The protein levels of ZO-1 and VE-Cad were decreased, while the levels of NOX4, NLRP3 inflammasome-related proteins and ROS generation were increased in high glucose-treated HRMECs. Silencing of NOX4 inhibited high glucose-induced increases in NLRP3 inflammasome and ROS generation, and decreases in the protein levels of ZO-1 and VE-Cad. Over-expression of NOX4 significantly increased the levels of NLRP3 inflammasome-related proteins and ROS generation in HRMECs, and reduced the protein levels of ZO-1 and VE-Cad. Treatment with SDX partly reversed NOX4 over-expression-induced changes. CONCLUSION SDX alleviates hyperglycemia-induced retinal microvascular endothelial injury via inhibiting NOX4/ROS/NLRP3 pathways.  相似文献   
50.
This study was conducted to evaluate the effects of different concentrations of dietary lipids on body composition and liver function in juvenile red drum, Sciaenops ocellatus. Diets were formulated to contain 40% crude protein from solvent-extracted menhaden fish meal and 0, 7, 14 or 21% lipid from menhaden fish oil. The basal diet, without supplemental fish oil, contained lipid at 0.4% of dry weight. The diets were fed to groups of 25 juvenile red drum initially averaging 7.3 ± 0.18 g fish–1 in a recirculating culture system for 8 weeks and weight gain was recorded. After an additional 8 weeks, 16 fish from each treatment were sacrificed and the following measurements were recorded: hepatosomatic index (HSI), intraperitoneal fat (IPF) ratio, and liver -tocopherol, malondialdehyde (MDA) formation, and cytochrome P-4501A activity (measured as 7-ethoxyresorufin O-deethylase (EROD) activity). The activity of alanine and aspartate aminotransferases and concentrations of -tocopherol also were measured in plasma.Weight gain was significantly (p<0.05) affected by dietary lipid concentration, with values ranging from 361% of initial weight for fish fed the basal diet to 527% of initial weight for fish fed the diet containing 7% lipid. The HSI and IPF ratio values also were significantly affected by lipid with the lowest values recorded for fish fed the basal diet and the highest values observed in fish fed the diet containing 21% lipid. Increasing dietary lipid significantly increased oxidative stress as reflected in reduced -tocopherol in liver and plasma and increased MDA formation in the liver, although no overt pathological signs were observed. These findings suggest that lipid concentrations between 7 and 14%, when the diet contains 60 IU vitamin E kg–1, are likely to limit oxidative stress and result in normal physiological responses of red drum.  相似文献   
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