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In the present study, we aimed to investigate a protective role for resveratrol against the effects of immobilization stress on corpora lutea(CL) of mice in early pregnancy. A total of 45 early-pregnant mice were divided into no immobilization stress(NIS) group, immobilization stress(IS) group, and immobilization and resveratrol treatment(IS+RES) group(n=15). Mice were immobilized in plastic tubes(50 mL) for 3 h per day during day 1 to 7 of pregnancy. In the IS+RES group, 5 mg kg–1 d–1 of resveratrol was administered just prior to application of stress. We analyzed apoptotic activity in CL by Western blotting analysis(WB), transmission electron microscopy(TEM), and immunohistochemistry(IHC). Serum progesterone levels were examined with radioimmunoassay(RIA). IHC results showed that the intensity of positive staining for Bax was increased, and for Bcl-2 was decreased in CL after IS, while resveratrol treatment reversed the positive staining for Bax and Bcl-2. WB revealed that immobilization stress up-regulated the expression of Bax and caspase-9, and downregulated Bcl-2 expression, while resveratrol treatment attenuated the effects of immobilization stress on the expression of Bax, Bcl-2 and caspase-9. According to our TEM results, apoptosis as defined by chromatin condensation was found in CL after immobilization stress, while resveratrol inhibited the apoptosis. We also demonstrated that immobilization stress decreased progesterone concentrations and ovarian expression of StAR, while resveratrol restored the concentrations of progesterone and expression of StAR back to normal. These results indicated that immobilization stress induced luteal regression while resveratrol inhibited luteal regression, suggesting that resveratrol plays a protective role on corpora lutea of mice during early pregnancy.  相似文献   
3.
湘南地区引进杂柑天草接穗在尾张温州蜜柑树上进行高接换种研究发现:高接后第二年始果,第三年有一定产量;春季萌动始于3月上旬,3月中旬现蕾,4月中下旬盛花期,5月下旬至10月底为果实膨大期,果实成熟期在11月中下旬;果实平均单果重206 g;果实汁多味浓,可溶性固形物12.9%,100 g鲜果肉含维生素C 33.17 mg,可滴定酸0.53%;树势中等偏弱。  相似文献   
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应用层理结构的分类指标——流核比 ,对泥石流堆积层理的正粒序、反粒序和混杂粒序等进行成因差异分析。当粘性泥石流体的流核比在 12~ 5 0之间时 ,砾石质点在蠕动流场中作向上垂直运动 ,形成筛积的层理结构。  相似文献   
6.
辽宁省盘锦沿海地区田菁的栽培及其改良盐土的效果   总被引:1,自引:0,他引:1  
辽宁省滨海盐渍土多分布于低洼易涝地区,以盘锦沿海地区为主.这些盐碱地,除部分已开垦种植外,尚有大面积荒地.已被垦殖的土地,也因盐碱重,肥力低,危害作物出苗和生长,引起作物减产,甚至成片死亡,严重地影响单位面积产量和总产量.为了加速盐碱地的改造利用,使达到稳产高产,种植绿肥作物是有效措施之一;特别是在水旱轮作中,绿肥占着重要的地位.因此研究绿肥作物的栽培和提高土壤肥力的作用,对农业生产的发展具有重大的实践意义.本文系根据1957年到1964年的部分研究资料加以整理,供各地参考.  相似文献   
7.
根据香菇单核菌丝体135A和135B的全基因组测序,通过生物信息学方法分析筛选出香菇功能基因CAP、GLA1、TLG1结构域中的非同义SNP位点,开发出3对SNP-CAPS分子标记。结果表明:这3对功能基因SNP-CAPS分子标记可将23个香菇单核体供试菌株分成135A型(分别为16株、20株、2株)和135B型(分别为7株、3株、21株),这些标记表现出的多态性为进一步研究香菇菌株的来源和功能基因的定位提供参考价值;并建立起可以简单、快速、准确地调查重要功能基因的SNP位点变异情况的方法。  相似文献   
8.
不同施肥技术对南方红豆杉幼林生长量的影响   总被引:2,自引:0,他引:2  
通过正交试验设计探索研究施用不同种类肥料、不同施肥数量及不同施肥方法对南方红豆杉幼林生长量的影响差异。结果表明:在福建省闽南海拔600m以上丘陵山地以A3(硫酸钾复合肥+发酵牛粪便)+B2(硫酸钾复合肥10g+发酵牛粪便100g)+C1(放射沟施)最佳;1a生南方红豆杉幼林平均地径达2.5cm,平均高达146.3cm。  相似文献   
9.
Objective To examine circulating total and free thyroid hormone (T3 and T4) concentrations, determine serum iodothyronine binding characteristics and estimate thyroid stimulating hormone (TSH) activity in sera of coastal and inland koalas.
Design A prospective study.
Procedure Koala serum T3 and T4 were measured by radioimmunoassay. T4 binding parameters were determined by radioligand binding and electrophoresis. Koala TSH values were determined by bioassay.
Results Mean total T4 concentrations were 3.2 ± 2.1 nM although values were significantly higher in inland-dwelling females in comparison to coastal-dwelling males. Free T4 was 3.3 ± 2.1 pM. Total and free T3 were 0.4 ± 0.2 nM and 1.4 ± 0.9 pM respectively, although these values were at the lower end of the assay detection limit and should be viewed with reservation. Electrophoresis of [125I]-T4-labelled serum revealed only two proteins of electrophoretic mobility similar to human transthyretin (TTR) and albumin. Scatchard analysis of T4 binding to serum gave a curvilinear plot, which could be resolved into two binding sites with affinities identical to that of TTR and albumin but both of low concentration. The bioactivity of the TSH present in the sera was measured using a cell line (JP09) transfected with the human TSH receptor. The mean level of stimulation found in the sera corresponded to a bovine TSH activity of less than 10 mU/L.
Conclusion These results suggest that the serum concentrations of free and total thyroid hormones in koalas are low compared to other marsupials and very low compared to eutherian mammals. The mechanism of maintenance of euthyroidism in this species remains to be determined.  相似文献   
10.
Six dogs with previously implanted arterial, central venous, pulmonary arterial and left atrial catheters received halothane anaesthesia, and halothane anaesthesia plus administration of a balanced electrolyte solution given over one hour, in a cross-over experiment. Parameters measured included temperature, heart rate (HR), respiratory rate (f), arterial and mixed venous blood-gases and acid-base parameters, mean arterial pressure ( AP ), mean pulmonary artery pressure ( PAP ), mean left atrial pressure ( LAP ), mean central venous pressure ( CVP ), packed cell volume (PCV), total plasma protein (TPP), plasma sodium, potassium and chloride concentrations, and urinary sodium and potassium concentrations.
During halothane anaesthesia there were significant decreases in AP , PCV, TPP, f, and significant increases in arterial and mixed venous oxygen, and glucose concentrations, when compared with conscious control values. When intravenous fluid was administered during anaesthesia, there were significant decreases in temperature, AP , PCV and TPP, with significant increases in PAP , CVP and f, when compared with values during anaesthesia alone. After one hour recovery period from anaesthesia, dogs receiving intravenous fluids had significantly decreased PaO2 values and significantly increased pH when compared with anaesthesia alone. There was an average urinary excretion of 7 mmol of sodium and 5 mmol of potassium during anaesthesia, and 36 mmol of sodium and 8 mmol potassium during fluid administration.  相似文献   
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