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991.
Seung-Hwan Kwon Shi-Xun Ma Hyun-Joong Joo Seok-Yong Lee Choon-Gon Jang 《Biomolecules & therapeutics.》2013,21(6):462-469
Eucommia ulmoides Oliv. Bark (EUE) is commonly used for the treatment of hypertension, rheumatoid arthritis, lumbago, and ischialgia as well as to promote longevity. In this study, we tested the effects of EUE aqueous extract in graded doses to protect and enhance cognition in scopolamine-induced learning and memory impairments in mice. EUE significantly improved the impairment of short-term or working memory induced by scopolamine in the Y-maze and significantly reversed learning and memory deficits in mice as measured by the passive avoidance and Morris water maze tests. One day after the last trial session of the Morris water maze test (probe trial session), EUE dramatically increased the latency time in the target quadrant in a dose-dependent manner. Furthermore, EUE significantly inhibited acetylcholinesterase (AChE) and thiobarbituric acid reactive substance (TBARS) activities in the hippocampus and frontal cortex in a dose-dependent manner. EUE also markedly increased brain-derived neurotrophic factor (BDNF) and phosphorylation of cAMP element binding protein (CREB) in the hippocampus of scopolamine-induced mice. Based on these findings, we suggest that EUE may be useful for the treatment of cognitive deficits, and that the beneficial effects of EUE are mediated, in part, by cholinergic signaling enhancement and/or protection. 相似文献
992.
英国伦理委员会的现状与分析 总被引:1,自引:0,他引:1
伦理委员会的主要职责是保护药物临床试验受试者的权益、安全和健康.现对英国伦理委员会的法律、法规、申请及审评程序等进行归纳分析,旨在对规范我国伦理委员会的运作具有参考借鉴作用. 相似文献
993.
目的了解婴幼儿泪囊炎病原菌的分布及耐药情况,为临床合理用药提供依据。方法用常规方法对婴幼儿泪囊炎分泌物标本进行病原菌分离培养鉴定,用纸片扩散法(K-B法)进行药物敏感性试验,对分离出的病原菌分布及耐药性进行分析。结果共分离出非重复病原菌208株,其中革兰阴性杆菌105株占50.5%(105/208),革兰阳性球菌100株占48.1%(100/208),真菌3株占1.4%(3/208)。分离率居首位的为肺炎链球菌占17.3%(36/208),其次为表皮葡萄球菌占13.0%(27/208)、肺炎克雷伯菌占10.6%(22/208)和副流感嗜血杆菌占9.6%(20/208)。氧氟沙星和左氧氟沙星对以上4种主要病原菌耐药率均〈30%。结论婴幼儿泪囊炎病原菌以肺炎链球菌、表皮葡萄球菌、肺炎克雷伯菌和副流感嗜血杆菌为主。氧氟沙星和左氧氟沙星对婴幼儿泪囊炎病原菌均具有较好的体外抗菌活性。 相似文献
994.
目的 探索添加"正圆形标记"后对印模固有形变规律的影响.方法 按美国牙科协会ADA标准,制作两个金属母模,并在其中1个上安置6根横断面为正圆形的钢针.分别对两个金属母模制取印模,获得A、B两组印模样本.用测量显微镜观察、测量标记线,比较两组印模的形变程度及规律.所获数据采用SAS 6.12软件的成组t检验比较.结果 A、B两组印模的形变范围分别为,藻酸盐0.38%~0.58%和0.43%~0.66%;硅橡胶0.38%~0.42%和0.33%~0.49%,两组之间差异无统计学意义(P〉0.05).结论 在口腔印模上添加正圆形标记点,不会影响印模本身固有的形变规律,该标记方法是可行的. 相似文献
995.
"生物海盗"事件频发,拥有丰富遗传资源和相关传统知识的发展中国家呼吁建立获取与惠益分享的国际制度,以管理遗传资源及其相关传统知识获取、利用和惠益分享行为,保障遗传资源及其相关传统知识提供者权益.《生物多样性公约》及其《名古屋议定书》等一系列国际文书的通过,逐渐完善了遗传资源获取和惠益分享国际规则和制度体系,保障了遗传资... 相似文献
996.
Bisma Parveez Nur Ayuni Jamal Hazleen Anuar Yusilawati Ahmad Abdul Aabid Muneer Baig 《Materials》2022,15(15)
Metal foams possess remarkable properties, such as lightweight, high compressive strength, lower specific weight, high stiffness, and high energy absorption. These properties make them highly desirable for many engineering applications, including lightweight materials, energy-absorption devices for aerospace and automotive industries, etc. For such potential applications, it is essential to understand the mechanical behaviour of these foams. Producing metal foams is a highly challenging task due to the coexistence of solid, liquid, and gaseous phases at different temperatures. Although numerous techniques are available for producing metal foams, fabricating foamed metal still suffers from imperfections and inconsistencies. Thus, a good understanding of various processing techniques and properties of the resulting foams is essential to improve the foam quality. This review discussed the types of metal foams available in the market and their properties, providing an overview of the production techniques involved and the contribution of metal foams to various applications. This review also discussed the challenges in foam fabrications and proposed several solutions to address these problems. 相似文献
997.
This paper addressed the issues of both direct and indirect synthesis of Ni aluminides by pack cementation (pure Ni and IN 718 superalloy). On the Al-Ni diffusion twosome under pressure, at temperatures below and above the Al melting temperature, the appearance and evolution of diffusion porosity because of the Kirkendall–Frenkel effect manifestation was highlighted. It has been confirmed that, as the temperature rises above the Al melting temperature, the porosity decreases. Nickel-based superalloys, and in particular IN 718, significantly increase their performance by increasing the aluminides proportion in the top diffusion coating. This is made possible by changing the value of the Al and Ni weight percentage ratio in this area (noted as Al/Ni). In the case of the diffusion twosome between IN 718 and pack aluminizing mixtures, having in their composition as active components Al powder, Ferroaluminum (FeAl40) or mixtures of Al and Fe powders, at processing temperatures above the Al melting temperature, by modifying the active component of the mixture, substantial changes in the Al/Ni values were observed, as well as in the maximum %Al in the diffusion coating and of its thickness. It was found that, when switching from Al to FeAl40 or powder mixture (Al + Fe), the Al/Ni value changes between 3.43 and 1.01, from initial subunit values. The experiments confirmed that the highest %Al in the top aluminized diffusion coating, for IN 718, was obtained if the powder mixture contained 66.34 wt.% Al. 相似文献
998.
VINCENT J. HYAMS 《Clinical otolaryngology》1978,3(2):117-126
The differential diagnosis of approximately 2000 cases of palatine tonsillar malignancy contained in the Otolaryngic Pathology Registry of the Armed Forces Institute of Pathology are presented to include basic statistics of age, race and sex. These statistics and others from the World English language medical literature are compared and discussed briefly. Pertinent information points out the overwhelming predominance of squamous (epidermoid) carcinoma, the delayed medical attention of patients and hence the advanced clinical state of the disease when first diagnosed, the involvement of cervical lymph nodes in the majority of cases and the causative relationship of alcoholism. A discussion of the various histological types of tonsillar carcinoma suggests a simplification of the current microscopic classification. 相似文献
999.
目的评价鼻腔扩容术治疗OSAHS患者主客观症状的改善情况。方法观察30例行鼻腔扩容术的成年OSAHS患者,所有患者于术前进行多道睡眠图(PSG)描记,鼻声反射和鼻阻力测试等鼻功能检查,填写白天嗜睡主观评分Epworth嗜睡量表(Epworth sleepiness score,ESS)、鼻塞主观视觉模拟量表(visual analogue scale,VAS)评分、鼾声评分量表,以上主客观检查于鼻腔手术后3个月重复记录。所有患者接受鼻腔扩容术(鼻中隔三线减张成形术、双侧下鼻甲外移、双侧中鼻甲内移和双侧中鼻道鼻窦对称性开放)。结果鼻腔扩容术后患者鼻腔总阻力显著降低[(0.89±0.23)kPa·s/L vs(0.29±0.12)kPa·s/L,P〈0.01],鼻塞VAS评分显著降低[8.2±1.1 vs 2.1±0.73,P〈0.01],白天嗜睡ESS评分显著降低(12.7±1.2 vs 8.6±2.9,P〈0.01),打鼾程度减轻(62.2±25.6 vs 45.6±18.6,P〈0.01)。轻度OSAHS患者呼吸暂停低通气指数(apnea and hypopnea index,AHI)较术前显著下降(P〈0.05),觉醒指数较术前显著下降(P〈0.01),最低动脉血氧饱和度(lowest SaO2,LSaO2)较术前显著升高(P〈0.01)。中度和重度OSAHS患者的AHI指数、觉醒指数、LSaO2均较术前无显著改变(P〉0.05)。LSaO2、睡眠结构各阶段的比例、快动眼睡眠阶段的长度在所有OSAHS患者均没有显著变化(P〉0.05)。30例OSAHS患者鼻腔扩容术的总体有效率为26.7%。结论鼻腔扩容手术可以改善OSAHS患者鼻塞及白天嗜睡、睡眠打鼾等相关睡眠主观症状,并在一定程度上改善OSAHS患者的阻塞性睡眠呼吸暂停的严重程度,应适当选择其手术适应证。 相似文献
1000.
目的 探讨头颈肿瘤组织标本的采集、保存,组织库构建方法,以及信息化管理技术。方法 收集手术切除和活检的头颈肿瘤组织、癌旁组织、远端正常组织及患者和正常人外周血标本(分离出血清、血浆、淋巴细胞、干细胞等),置于液氮或-80℃低温冰箱冷冻保存;同时建立一套系统管理组织标本库,使标本库规模化、信息化、智能化。结果 共收集新鲜组织标本220份,血液标本476份。其中肿瘤组织120份(包括肿瘤组织、癌旁组织);非肿瘤组织100份。肿瘤患者血液标本316份,非肿瘤患者血液标本160份。结论 标本库的建立使少见的头颈肿瘤组织标本集约化、规模化,极大提高了标本利用的效率,达到了资源共享的目的。 相似文献