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91.
目的:探讨ω-3多不饱和脂肪酸和三羟异黄酮孕期营养干预对子代大鼠乳腺癌增殖细胞核抗原(PCNA)、雌激素受体(ER)、乳腺癌易感基因1(BRCA1)表达的影响.方法:怀孕大鼠随机分为正常对照组、ω-3多不饱和脂肪酸组、三羟异黄酮低剂量组、三羟异黄酮高剂量组、ω-3多不饱和脂肪酸和三羟异黄酮混合组.选用其雌性子代进行甲基亚硝基脲(MNU)诱导乳腺癌.其中母体为正常对照的分别为子代的正常对照组(Con)和模型组(Mod),其余分组按照母体暴露情况进行划分,分别为ω-3多不饱和脂肪酸组(ω-3PUFA)、三羟异黄酮低剂量组(LGEN)、三羟异黄酮高剂量组(HGEN)、ω-3多不饱和脂肪酸和三羟异黄酮混合组(ω-3PUFA+GEN).观察其乳腺癌发生情况,同时采用RT-PCR和免疫组化检测正常乳腺组织和乳腺癌组织中PCNA、ER和BR-CA1的mRNA或蛋白表达水平.结果:ω-3多不饱和脂肪酸和三羟异黄酮孕期营养干预后可以减少雌性子代MNU诱导乳腺癌的发生,与Con组比较,Mod组乳腺癌组织中BRCA1和ER mRNA表达水平上调,PCNA、ER表达量增加.与Mod组比较,ω-3PUFA组、GEN组乳腺癌组织中BRCA1、ERmRNA及PCNA、ER表达量明显降低.结论:孕期暴露于ω-3PUFA和GEN可降低雌性子代MNU诱导乳腺癌的发生,并下调PCNA、ER和BRCA1的表达量. 相似文献
92.
药用真菌子实体多糖SEC-HPLC图谱的相似度定量评价研究 总被引:1,自引:0,他引:1
目的:对灵芝属Ganoderma下4个种共7个菌株及灰树花Grifola frondosa和云芝Trametes versicolor共9种子实体粗多糖进行了体积排阻HPLC色谱(SEC-HPLC),并分析了相似度.方法:各样品水提物的HPLC图谱用平方欧氏距离法计算了相似度,用离差平方和法进行聚类分析.结果:灵芝属内各样品聚类距离为8,灰树花与云芝的聚类距离为16,它们与灵芝属的距离为25,说明同一灵芝属内的不同种及同种不同菌株所产生的多糖分子量分布近似度远高于来自树花菌属的灰树花或栓菌属的云芝.结论:此方法可量化描述不同多糖间SEC-HPLC的相似关系,有作为真菌多糖样品质量控制手段的潜在能力. 相似文献
93.
Akirin是近来发现的在骨骼肌生长发育和免疫反应中具有重要作用的基因。简要综述了akirin基因与免疫反应、骨骼肌发育和再生、myostatin基因和NF-κB因子的关系,同时分析了禽类akirin2基因的研究进展,最后对akirin基因的应用前景也进行了简单探讨,以期为akirin基因在医学和畜牧业中的深入研究和应用提供参考。 相似文献
94.
3-Nitropropionic acid (3-NP), an irreversible inhibitor of succinate dehydrogenase enzyme (SDH), induces neurodegeneration similar to that observed in Huntington’s disease (HD). Reduction of prepulse inhibition (PPI) of acoustic startle response, locomotor hypoactivity, bilateral striatal lesions as well as brain oxidative stress are major features of HD. The present study was designed to investigate neuroprotective effect of Ginkgo biloba extract (EGb 761) on 3-NP induced neurobehavioral changes and striatal lesions.Rats administered 3-NP (20 mg/kg, s.c.) for five consecutive days exhibited PPI deficits and locomotor hypoactivity whereas, pretreatment of animals with EGb 761 (100 mg/kg, i.p. for 15 days) ahead of and during the induction of HD by 3-NP (20 mg/kg for 5 days starting at day 8) ameliorated 3-NP-induced neurobehavioral deficits. Administration of 3-NP increased the level of striatal malondialdehyde (MDA). This effect was prevented in animals pre-treated with EGb 761. Changes in the level of apoptotic regulatory gene expressions, following 3-NP treatment, were demonstrated as both an up-regulation and a down-regulation of the expression levels of striatal Bax and Bcl-xl genes, respectively. In addition, an up-regulation of the expression level of striatal glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was also observed. Pre-treatment with EGb 761 caused a down-regulation in striatal GAPDH and Bax together with an up-regulation of striatal Bcl-xl expression level as compared to the 3-NP treated group. Histochemical examination of striatal tissue showed that EGb 761 significantly prevented 3-NP induced inhibition of SDH activity. Histopathological examination further affirmed the neuroprotective effect of EGb 761 against 3-NP toxicity.Taken together, these results suggest that EGb 761 has a neuroprotective role in the current HD paradigm, which may be related to improvement of energy metabolism, antioxidant properties and antiapoptotic effects. 相似文献
95.
96.
目的:研究人参皂甙Rd(Ginsenoside Rd)预处理对谷氨酸所致PC12细胞损伤的影响。方法:将体外培养的PC12细胞分为3组,分别为对照组(Control)、谷氨酸损伤组(Glu)和人参皂甙Rd预处理组(Rd)。Control组细胞正常培养;Glu组细胞暴露于含10mM谷氨酸的DMEM培养基中损伤24 h;Rd组细胞经50μM的人参皂甙Rd预处理30 min后,在谷氨酸浓度为10 mM的DMEM培养基中损伤24 h。采用MTT检测细胞活力和乳酸脱氢酶(LDH)检测试剂盒检测LDH释放量;流式细胞仪检测胞内活性氧(ROS)水平;Western blot检测还原型谷胱甘肽蛋白(GSH)表达;专用试剂盒检测细胞内过氧化氢酶(CAT)和超氧化物歧化酶(SOD)含量,相差显微镜观测细胞形态。结果:50μM的人参皂甙Rd预处理30 min,可明显提高谷氨酸诱导的PC12细胞的活力,降低其LDH释放量、胞内ROS含量,并提高胞内GSH蛋白表达,增加CAT、SOD含量并改善细胞形态。结论:人参皂甙Rd预处理可减轻谷氨酸引起的PC12细胞损伤。 相似文献
97.
Micelle‐enhanced spectrofluorimetric method for determination of sitagliptin and identification of potential alkaline degradation products using LC‐MS
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A novel, quick, simple and highly sensitive spectrofluorimetric method was developed and validated for the determination of sitagliptin (SG) in its pharmaceutical formulations. The proposed method is based on investigation of the fluorescence spectral behavior of sitagliptin in an SDS micellar system. In an aqueous solution of phosphate buffer pH 4.0, the fluorescence intensity of SG in the presence of SDS was greatly enhanced, by 200%, i.e. twofold enhancement. The fluorescence intensity of SG was measured at 300 nm after excitation at 270 nm. The method showed good linearity in the range 0.03–10.0 µg/mL with a good correlation coefficient (r = 0.9998). The limits of detection and quantitation values were 5.31 and 16.1 ng/mL, respectively. The proposed method was successfully applied to the analysis of SG in its single and co‐formulated commercial tablets; the results were in good agreement with those obtained using a reference method. Application of the proposed method was extended to stability studies of SG after exposure to different forced degradation conditions according to the ICH guidelines, such as acidic, alkaline, thermal, photo‐ and oxidative stress. The chemical structure of certain potential degradation products (DPs) were investigated using LC‐MS. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
98.
一直以来,生态学家和进化生物学家对森林群落物种多样格局及其形成机制持有不同的观点。虽然Robert Ricklefs将进化和生态过程整合的观点已经被群落生态学家广泛接受,但是区域物种进化历史以及局域群落微进化过程是否能够影响群落生态学过程以及这些过程如何影响群落结构和动态还有待商榷。经典的生态位理论同时强调了种间和种内生态位分化对群落多样性维持的影响。但是生态学家普遍认为种间差异足以代表群落内个体间的相互作用关系,并且由于进化过程导致的种内分化往往涉及较长的时间尺度,因此,虽然种内差异是自然选择的重要材料,物种对环境的适应性进化过程所导致的种内分化对群落构建的影响往往被生态学家所忽视。为此,通过回顾种间和个体生态位分化的研究历史,对两类研究分别进行简要阐述,强调在今后的群落生态学研究中需要考虑个体分化对局域群落构建的影响。 相似文献
99.
Thirty five females and 15 males of New Zealand White mature rabbits about 6 months of age, were assigned to 1–5 dietary treatments (7 does+3 bucks for each): uncontaminated control diet, naturally aflatoxin contaminated diet without or with 1,2 and 3% bentonite. Rabbit fed with the aflatoxin-diet had a decreased (P<0.01 or 0.05) physical semen characteristics of bucks and a reproductive performance traits of does. The values of conception rate (%), gestation length (days), litter size (n) and litter weights (g) at birth and viability (%) of litters of doe rabbits, fed with the aflatoxin-diet, recorded, respectively: 64.5; 31.0; 4.4; 275.0 and 57.1 versus 85.6; 30.3; 7.9; 508.0; and 100 for those fed with the uncontaminated diet. Addition of bentonite to the aflatoxin contaminated diet improved in general the physical semen characteristics of buck and reproductive performance traits of doe rabbits. The results of the study demonstrate that adding 1% of Egyptian raw bentonite to the naturally aflatoxin contaminated rabbit diets can provide an effective, cheap and safe practical technique for preventing the aflatoxicosis in mature rabbits. 相似文献
100.
目的:探讨大鼠补充一定剂量牛磺酸及微量营养素后,能否通过影响视感受器或视中枢NO合成酶(NOS)表达及第二信使(cGMP)合成,影响视觉信号传导。方法:Wistar大鼠随机分为三组,即对照组(正常饲料组)、实验1组(5倍需要量组)和实验2组(10倍需要量组),喂养3周后,每组动物再随机分为光照组和暗适应组(平均照度为3.03LX),以正常饲料喂养72h,大鼠活杀取样,以放射免疫方法分析cGMP含量 相似文献