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91.
92.
番鸭就巢期生殖激素水平的变化规律   总被引:10,自引:0,他引:10  
对番鸭就巢期不同时间的血浆生殖激素水平进行测试,揭示了不同就巢时间血浆生殖激素浓度变化的规律,并对就巢与激素之间的相关性进行分析。结果表明:(1)抱窝期血浆PRL含量(0.68±0.11ng/mL)极显著高于醒抱期的含量(0.33±0.04ng/mL)(P<0.01);(2)醒抱前后血浆LH含量差异很大,醒抱后LH含量(33.17±15.49mIU/mL)极显著高于抱窝期含量(5.56±1.99mIU/mL)(P<0.01);(3)抱窝期血浆E2含量(0.9±0.65ng/mL)极显著低于醒抱期含量(1.9±1.17ng/mL)(P<0.01);(4)PRL与LH、PRL与E2、LH与E2之间的相关系数分别为-0.923、-0.666和0.641。  相似文献   
93.
利用垂体细胞单层培养模型研究了30,60,90,120和150日龄北京黑猪母猪垂体细胞LH和FSH的释放及其对LRH-A3反应能力。结果表明,猪垂体细胞LH和FSH释放对LRH-A3的反应呈S形剂量依赖型同线。LH基础释放量和LRH-A3刺激的最大释放量在不同日龄间没有显著差异,说明初情期前母猪垂体细胞已达最大LH释放和对GnRH反应的能力。FSH的基础释放量和LRH-A3刺激的最在释放量在30日龄与60日龄之间无差异,但90日龄以后垂体细胞FSH的释施量随日龄增大而降低,提出可能由于垂体在体内时受过抑制素的作用。  相似文献   
94.
抑制素被动免疫对黄体中期山羊生殖激素分泌的影响   总被引:6,自引:0,他引:6  
为了探讨抑制素在山羊生殖激素分泌调节中的作用 ,本试验用抗抑制素血清对黄体中期雌山羊进行了被动免疫试验。将酪 30 -抑制素 α(1,30 ) NH2 与兔血清白蛋白螯合 ,用去势雄山羊制备抗抑制素血清 (INH- AS) ,最终滴度为 1∶96 0 0 0。对照血清来自牛血清白蛋白免疫的去势雄山羊。 12只黄体期日本 SHIBA山羊 ,肌注 PGF2α(2 mg/只 )进行同期发情处理 ,处理后 3~ 5 d母羊出现发情。在发情后 10 d(发情当天为 0 d) ,将母羊分为 2组 ,每组 6只。试验组颈静脉注射 INH- AS(2 0 m L /只 ) ,并在注射前 (0 h)和注射后 6、12、2 4、4 8、72、96、12 0 h采取外周血样 (肝素抗凝 ) ;对照组注射对照血清 (2 0 m L/只 )。抗凝血样离心 (4℃、170× g、15 min)分离血清 ,- 2 0℃保存待测。血清 FSH和 L H含量用NIDDK放免试剂盒测定 ,其中 FSH标记纯品为 NIDDK- o FSH- I- 1,标准品为 NIDDK- o FSH- RO- 1,一抗为 NIDDK-抗- o FSH- 1;L H标记纯品为 NIDDK- o L H- I- 3,标准品为 NIDDK- o L H- RP- 2 4 ,一抗为抗 - o L H- YM。二抗为山羊抗家兔Ig G。血清 E2 和 P含量用1 2 5I放免盒测定。测 E2 时 ,为除去游离脂肪 ,样品用 0 .5 m L乙腈 +2 m L乙烷处理。试验结果表明 ,注射 INH- AS后 12 h,血清 FSH含量显著提高  相似文献   
95.
本实验采用放射免疫测定技术(RIA)分析了9头屡配不孕母牛和6头正常母牛于发情开始后8天内的血清促黄体素(LH)的含量变化。测定结果表明:屡配不孕母牛的LH排卵峰值低于正常母牛,其峰值分别为2.71±1.00ng/ml和4.70±1.71ng/ml,差异显著(P<0.025)。为了初步验证LH峰值与屡配不孕之间的关系,对20头屡配不孕母牛在发情开始至配种前肌肉注射外源性LH180IU,其配种后60天的受胎率为70%(14/20),而未用LH处理的11头屡配不孕母牛的受胎率为18%(2/11),两者差异极显著(P<0.01)。上述实验结果提示:体内LH排卵峰值降低可能是导致乳牛屡配不孕的重要原因之一。  相似文献   
96.
Basal activities of certain pheasant hepatic and intestinal biotransformation enzymes and modulation of their activities by anthelmintics flubendazole (FLBZ) and mebendazole (MBZ) were investigated in subcellular fractions that were prepared from liver and small intestine of control and FLBZ or MBZ treated birds. Several oxidation, reduction and conjugation enzyme activities were assessed. In the liver, treatment of pheasants by FLBZ or MBZ caused very slight or no changes in monooxygenase activities and conjugation enzymes. More significative changes were detected in small intestine. Metyrapone and daunorubicin reductase activities were increased by both substances in the liver. This is the first evidence that certain benzimidazoles modulate reductases of carbonyl group. With respect to the relatively slight extent of the changes caused by FLBZ or MBZ we can assume that repeated administration of therapeutic doses of both FLBZ and MBZ has probably no serious influence on pheasant biotransformation enzyme system.  相似文献   
97.
Cmponent Study on Flavonoids From Leaves of Dendrocalamus Latiflorus   总被引:5,自引:0,他引:5  
从麻竹(Dendrocalamus latiflorus)叶中分离得到四个黄酮类化合物。经性质和光谱(UV,IR,MS,1HNMR,13CNMR等)法鉴定其结构,分别为牡荆苷(?),芦丁(II),山奈酚-3-O-β-D-芸香糖苷(III),山奈酚-3-O-β-D-葡萄糖基(1-2)-α-L-鼠李糖苷(IV)。四种化合物均为首次从该植物中得到。  相似文献   
98.
Fan D  Zhou X  Zhao C  Chen H  Zhao Y  Gong X 《Fitoterapia》2011,82(6):805-810
Quercetin-3-O-β-D-glucuronide, isolated from Polygonum perfoliatum L., was evaluated by antiviral efficacy against influenza A virus and anti-inflammatory activity in vivo in mouse, and it was used for quality evaluation of P. perfoliatum L.. In vivo study, oral administration of quercetin-3-O-β-D-glucuronide significantly suppressed ear edema induced by dimethyl benzene and peritoneal permeability induced by acetic acid in mice, and quercetin-3-O-β-D-glucuronide also showed to possess inhibitory activity against influenza A virus (FLUAV). In the present study, additionally, a rapid, simple and sensitive method for quantitative analysis of quercetin-3-O-β-D-glucuronide in P. perfoliatum L. was developed using high performance liquid chromatography (HPLC) coupled with photodiode array detection. The separation was carried out on a Lichrosher-C18 column (250 mm × 4.6 mm, 5 μm) together with a C18 guard column at isocratic elution systems of methanol (A) and 0.05% aqueous phosphoric acid (B) (43:57, v/v) with detection wavelength at 258 nm and column temperature at 30 °C. The method was validated for linearity, repeatability, limit of quantification (LOQ), precision and robustness. The contents of quercetin-3-O-β-D-glucuronide in 28 samples from different regions of China were between 0.06% and 2.09%. The developed analytical method was applied to investigate P. perfoliatum L. and for quality control of the herb.  相似文献   
99.
Tang DQ  Wei YQ  Yin XX  Lu Q  Hao HH  Zhai YP  Wang JY  Ren J 《Fitoterapia》2011,82(6):920-926
Quercetin's protective effects on the glomerulosclerosis of diabetic nephropathy (DN) in rat mesangial cells were investigated. The cell cycles, type IV collagen and laminin, TGF-β1 mRNA, Smad 2/3 and Smad 7, and activities of cell antioxidases were measured. Compared with the high glucose group, quercetin may decrease the cell percentages of G0/G1 phase, Smad 2/3 expression, laminin and type IV collagen, and TGF-β1 mRNA level significantly. The antioxidant capacity, the cell percentages of S phase and Smad 7 expression was significantly increased by quercetin. These results suggest that quercetin is a protective agent against glomerulosclerosis in DN.  相似文献   
100.
The present study was undertaken in five major forest types (dominated by Quercus semecarpifolia, Quercus floribunda, Acer acuminatum, Abies pindrow and Aesculus indica, respectively) between 2400 and 2850 m a.s.l. in a moist temperate forest of the Mandal-Chopta area in the Garhwal region of Uttarakhand, India. The aim was to assess the variation in composition and diversity in different vegetation layers, i.e., herb, shrub and tree, among these five forest types. Diversity indices, such as the Shannon-Wiener diversity index, density, total basal cover, Simpson’s concentration of dominance index, Simpson’s diversity index, Pielou’s equitability, species richness, species heterogeneity and β-diversity, were calculated to understand community structures. Dominance-diversity curves were drawn to ascertain resource apportionment among various species in different forest types.  相似文献   
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