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101.
102.
目的:研究中国安氏Ⅰ类错成人与美国安氏Ⅰ类错白人牙颌颅面形态结构的差异。方法:从西安市11所大学2098名新生中选取符合标准的101名(男53名、女48名)安氏Ⅰ类错样本。拍摄头颅定位X线片,用第四军医大学口腔医学院头影测量软件测量,用Alabama分析法与美国安氏Ⅰ类错白人颅颌面测量结果进行比较分析。结果:中国西安地区安氏Ⅰ类错成人上下颌突度大,面型较突;平面倾斜度、上下中切牙倾斜度及下中切牙至NB线距均较大;Y轴相对SN平面夹角增大,生长方向为后下。结论:与美国安氏Ⅰ类错白人比较,中国西安地区安氏Ⅰ类错成人颅面结构呈现颌骨突度大、下切牙唇倾及下颌趋向后下等特征。 相似文献
103.
目的 探讨在浅低温体外循环心脏跳动下完成小儿室间隔缺损修补术的可行性。方法 18例小儿室间隔缺损随机分为观察组和对照组 ,观察组在浅低温体外循环心跳下修补室间隔缺损 ,对照组为常规心脏停跳下修补室间缺损。测定心肌同功酶释放和三磷酸腺苷 ,观察左室压力 ,评价术野显露及气栓预防效果等。结果 观察组心肌同功酶释放明显低于对照组 ,三磷酸腺苷含量明显高于对照组 ,心肌超微结构基本正常 ,术中左室压力低于主动脉压力 ,术后无气栓发生。结论 浅低温体外循环心脏跳动下行小儿室间隔缺损修补术能更好地保护心肌。术野显露技术和防气栓的方法简便可行。 相似文献
104.
105.
K. Wyburn H. Wu G. Chen J. Yin J. Eris S. Chadban 《American journal of transplantation》2006,6(11):2612-2621
Interleukin-18 is predominantly a macrophage-derived cytokine with a key role in inflammation and cell-mediated immunity. Having previously demonstrated IL-18 upregulation in a rat model of kidney rejection, here we examined IL-18 in a fully MHC-mismatched murine model of acute kidney rejection using IL-18-deficient recipients (IL-18-/-) and animals administered neutralizing IL-18 binding protein (IL-18BP). Gene expression of IL-18 and its receptor were significantly upregulated in allografts compared to isografts, as was the cellular infiltrate (T cells and macrophages) (p < 0.001). Allografts developed kidney dysfunction (p < 0.05) and tubulitis (p < 0.01) not observed in controls. There was a significant reduction in gene expression of IL-18 downstream pro-inflammatory molecules (iNOS, TNFalpha and IFNgamma) in IL-18-/- recipients (p < 0.01), and IL-18BP-treated animals. The CD4+ infiltrate and IL-4 mRNA expression was greater in the IL-18-/- recipients than wild-type (WT) allografts and IL-18BP-treated animals (p < 0.05), suggesting a Th2-bias which was supported by IFNgamma and IL-4 ELISPOT data and an increased eosinophil accumulation (p < 0.001). Neither IL-18 deficiency nor neutralization prevented renal dysfunction or tubulitis. This study demonstrates increased production of IL-18 in murine kidney allograft rejection and provides evidence that IL-18-induced pathways of inflammation are active. However, neither IL-18 deficiency nor neutralization was protective against the development of allograft rejection. 相似文献
106.
Chuan-Bin Guo Nian-Hui Cui Guang-Yan Yu Ding-Xin Liu Shu-Cong Meng Qing Song 《Journal of oral and maxillofacial surgery》2003,61(8):909-912
PURPOSES: Inhibition of cerulenin on the endogenous fatty acid synthetic activities of oral squamous cell carcinoma (OSCC) and normal oral mucosa was assayed. METHODS: Squamous cell carcinoma and normal oral mucosa were collected fresh from surgical specimens. The collected tissues were minced in RPMI 1640 and divided into 3 groups: cerulenin treated, dimethylsulfoxide treated, and control. The tissues were incubated in [1(2)-(14)C]acetic acid, sodium salt for the last 2.5 hours of the treatment at 37 degrees C in 5% CO(2). After labeling, total lipids were extracted and counted for (14)C by scintillation counting. RESULTS: Endogenous fatty acid synthetic activities of oral squamous cell caranoma in the cerulenin-treated group decreased by 19% at 1 hour, 64% at 2 hours, and 87% at 4 hours; remained nearly unchanged in the dimethylsulfoxide-treated group; and increased slightly in the control group. The oral mucosa tissues were only mildly affected by cerulenin in fatty acid synthesis. CONCLUSIONS: Cerulenin significantly inhibits fatty acid synthetic activity in squamous cell carcinoma and only mildly affected the oral mucosa, indicating that the fatty acid synthetic pathway may be exploited as a target for developing anticancer drugs. 相似文献
107.
目的探讨高频超声引导定位穿刺前臂浅静脉的应用价值。方法对40例常规浅静脉穿刺失败,采用高频探头在同一体表区域寻找并标记浅静脉走行及深度,确认进针方向后再次静脉穿刺,必要时采用实时引导。结果11例经高频超声标记、29例经高频超声实时引导静脉穿刺均一次成功。结论高频超声引导下静脉穿刺的成功率高,无并发症,是一种简便有效的方法,值得在临床推广应用。 相似文献
108.
Alex Zacharek Jieli Chen Xu Cui Ang Li Yi Li Cynthia Roberts Yifan Feng Qi Gao Michael Chopp 《Journal of cerebral blood flow and metabolism》2007,27(10):1684-1691
Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2. 相似文献
109.
目的目前,对中国人抑郁体验的现象学理解很大程度上依赖于西方教科书和国际诊断系统中的描述。而临床经验告诉我们,不同地区、不同文化对情绪痛苦的表达有着各自的特点;但中国在这方面还缺乏研究。为此,我们采用民俗学方法对广州地区就诊人群的抑郁体验进行了研究。方法在广州市精神卫生中心门诊,采用定额取样招募40例有抑郁情绪的患者;问及的合适的病人共43人,只有3人不同意参加。采用开放式深入民俗学访谈了解患者的抑郁体验,即让患者用他们自己的话来讲述患病经历。对访谈进行录音,转录为文字并译成英文。对中英文记录分别进行了内容分析。结果除了西方教科书和诊断系统中描述的抑郁症状外,还发现了六个情感体验的类别:本地情感语汇、具身的情绪体验、隐含的忧伤、难以言状的痛苦、情绪不良造成的人际不和谐,以及专注于失眠。结论精神病学教科书和诊断系统中的描述未能涵盖中国抑郁患者对抑郁症状的全部体验。需要进一步研究抑郁体验与生活事件的关联及其在不同文化下的表现方式,这样才能作出与文化相适应的有效诊断。 相似文献
110.
目的 研究川芎嗪(tetraethylplyrazine,TMP)拮抗链霉素耳毒性作用及其对耳蜗外毛细胞外向K^+通道的影响,寻求两者的相关性,旨在探讨川芎嗪拮抗耳中毒作用的离子通道机制。方法 选取豚鼠60只,随机分为6组,即对照组、链霉素组、川芎嗪低浓度组、川芎嗪高浓度组、川芎嗪低浓度+链霉素组和川芎嗪高浓度+链霉素组,分别注射生理盐水(2.5ml/kg)、链霉素(450mg/kg)、川芎嗪(12mg/kg)、川芎嗪(60ms/ks)、川芎嗪(12mg/kg)+链霉素(450mg/kg)、川芎嗪(60mg/kg)+链霉素(450mg/kg),用药10天后检测各组豚鼠ABR反应阈,并采用全细胞膜片钳技术观察川芎嗪对耳蜗外毛细胞Ca^2+敏感K^+电流和延迟外向K^+电流的影响。结果 结果表明川芎嗪明显降低链霉素所致的豚鼠ABR反应阈升高,提示川芎嗪具有明显的拮抗链霉素耳毒性作用;川芎嗪能明显增大豚鼠耳蜗外毛细胞Ca^2+敏感K^+电流和延迟外向K^+电流,并呈浓度依赖关系。结论 川芎嗪可能通过增大K^+通道电流而发挥其降低链霉素耳毒性作用,推测这是其抗耳毒性作用机制之一。 相似文献