长期力竭性训练对大鼠海马神经元凋亡的影响

目的:研究长期力竭性训练对大鼠海马神经元凋亡的影响及其基因调控机制;方法:对大鼠进行为期8周的力竭性游泳训练,用DNA原位末端标记法检测海马神经元的凋亡,并用免疫组化的方法观察海马神经元中bcl-2、bax的免疫反应活性;结果:1)长期力竭性训练后,大鼠海马神经元凋亡显著增加.海马神经元凋亡可能是力竭性训练导致运动能力降低和中枢性运动疲劳的病理生理机制.2)长期力竭性训练后,大鼠海马神经元中bcl-2蛋白的表达显著下降,bax蛋白的表达显著增加.因此,力竭性训练可抑制海马神经元bcl-2蛋白的表达而促进bax蛋白的表达,这可能是力竭性训练导致大鼠海马神经元凋亡发生的基因调控机制.     

几个重要生物实验的改进

本文通过实践摸索,发现几个重要生物实验中存在的弊端,并探索出一些行之有效,简单易行的改进方法,给同行提供参考。     

岩坑尖2#隧道病害调查及等级评价

岩坑尖2#隧道是甬金高速公路中最长的隧道,在运营期间出现不少裂缝、掉块等病害。为了保证隧道安全运营,对隧道进行了裂缝、掉块、错台、渗漏水等病害调查,通过素描和量测手段记录了隧道病害,结合地质条件、施工、施工监控量测、现场调查情况,系统的总结分析了病害产生的原因。发现地质因素、设计因素、偏压荷载以及施工因素是导致该隧道衬砌病害的主要原因;最后阐述了隧道病害等级的划分方法,并评价了隧道的病害等级,该隧道处于AA级,提出来进一步观察以确定是否影响衬砌结构的承载力和下一步的病害处治措施。     

小寒、大寒节气对肺心病失代偿期病人的影响

慢性肺源性心脏病是老年人的常见病、多发病,随着我国逐渐进入老龄化社会,肺心病失代偿期对老年人、对家庭、对社会的各方面影响将不断扩大。文章主要运用我国传统医学的理论阐述小寒、大寒季节对本病产生的影响,对疾病的发展及预后起着重要的临床指导作用。     

内质网应激介导细胞凋亡在运动预防非酒精性脂肪肝形成中的作用

摘要：目的：探讨运动对非酒精性脂肪肝（NAFLD）的预防作用及作用机理。方法： SD雄性大鼠随机分为对照组、模型组和运动组3 组。对照组给予普通饲料喂养,模型组予高脂饲料喂养,运动组在高脂饲料喂养的同时予运动干预,连续8周,直至实验结束。HE染色观察肝脏病理形态变化,TUNEL法测肝细胞凋亡,western blot检测CHOP、Caspase12和JNK蛋白表达,免疫组化检测CHOP、Caspase12和JNK蛋白阳性表达。结果：1）与对照组比较,模型组肝细胞脂肪性变明显,肝细胞凋亡指数升高,CHOP、Caspase12、JNK蛋白表达及阳性表达增加;2）与模型组比较,运动组肝细胞脂肪变性减轻,肝细胞凋亡指数减少,CHOP、Caspase12、JNK蛋白表达及阳性表达降低。结论：8周高脂饮食可成功复制NAFLD动物模型,内质网应激介导细胞凋亡参与NAFLD形成。运动对NAFLD形成具有较好的预防作用,其机制可能与运动可降低内质网应激介导细胞凋亡蛋白CHOP、JNK和Caspase12在肝细胞的表达,抑制肝细胞凋亡有关。     

基于Simulink的燃料电池汽车混合动力电驱动系统仿真

首先分析了燃料电池汽车混合动力电驱动系统基本结构并给出了等效电路,建立了电驱动系统的动态数学模型,主要包括:燃料电池系统、动力蓄电池、电动机和DC/DC转换器四个模块。采用最小二乘法对模型的参数进行了估计,典型工况下的估计结果显示模型的准确性。其次根据设计目标要求,设计了主要部件的功率参数,并提出了适合不同工作模式的车辆控制策略。然后基于Simulink软件平台,建立了前向式仿真模型。最后进行仿真试验,其结果分析表明,建立的电驱动系统模型有较好的动力性、经济性和平顺性,为燃料电池汽车整车研究提供了仿真平台。     

《西游记》中的观音“疥癞”形象源流考

《西游记》第八回中观音为寻取经人,幻化模样后的人间形象是一个满身病疮的,衣衫褴褛的落魄和尚。在人们心目中法相庄严的观音怎么会幻化成这样一副模样？这绝不是信手拈来的自由发挥,而是有着文献依据的。通过一连串相互继连的记载可以考证出其源流。     

阿尔茨海默病发病机理的研究进展

阿尔茨海默病(Alzheimer’s disease,AD)病因及发病机制尚未完全阐明,有关其发病机制有β-淀粉样蛋白假说、Tau 蛋白假说、炎症学说和氧化应激学说等多种.本文就现有较公认的发病机制研究进展作一综述.     

A case study of imported pulmonary coccidioidomycosis

Coccidioidomycosis is an endemic disease of the Western hemisphere. The cases in non-endemic areas are mostly imported. Determining a history of exposure is critical for performing the diagnosis of coccidioidomycosis, especially for cases occurring in a non-endemic area. In this study, a 71-year-old Chinese male presented to our hospital with chronic cough and malaise, and was found to have a mass in the middle lobe of right lung. He had been visiting Arizona, USA for four months before admission. Pulmonary coccidioidomycosis was confirmed by the results of histopathological examination after lobectomy. Typical microscopic features of Coccidioides are definitely diagnostic, but need be differentiated from other budding yeast infection or carcinoma histopathologically.     

Effect of epidermal growth factor on follicle-stimulating hormone-induced proliferation of granulosa cells from chicken prehierarchical follicles

The development of ovarian follicular cells is controlled by multiple circulating and local hormones and factors, including follicle-stimulating hormone (FSH) and epidermal growth factor (EGF). In this study, the stage-specific effect of EGF on FSH-induced proliferation of granulosa cells was evaluated in the ovarian follicles of egg-laying chickens. Results showed that EGF and its receptor (EGFR) mRNAs displayed a high expression in granulosa cells from the prehierarchical follicles, including the large white follicle (LWF) and small yellow follicle (SYF), and thereafter the expression decreased markedly to the stage of the largest preovulatory follicle. SYF represents a turning point of EGF/EGFR mRNA expression during follicle selection. Subsequently the granulosa cells from SYF were cultured to reveal the mediation of EGF in FSH action. Cell proliferation was remarkably increased by treatment with either EGF or FSH (0.1–100 ng/ml). This result was confirmed by elevated proliferating cell nuclear antigen (PCNA) expression and decreased cell apoptosis. Furthermore, EGF-induced cell proliferation was accompanied by increased mRNA expressions of EGFR, FSH receptor, and the cell cycle-regulating genes (cyclins D1 and E1, cyclin-dependent kinases 2 and 6) as well as decreased expression of luteinizing hormone receptor mRNA. However, the EGF or FSH-elicited effect was reversed by simultaneous treatment with an EGFR inhibitor AG1478. In conclusion, EGF and EGFR expressions manifested stage-specific changes during follicular development and EGF mediated FSH-induced cell proliferation and retarded cell differentiation in the prehierarchical follicles. These expressions thus stimulated follicular growth before selection in the egg-laying chicken.