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91.
前庭水管扩大综合征患者的人工耳蜗植入术 总被引:19,自引:2,他引:19
目的 评价前庭水管扩大综合征患者人工耳蜗植入术的安全性和可行性。方法 1995年5月1日~2002年6月1日因双耳重-极重度感音神经性聋在北京协和医院接受人工耳蜗植入术的患者312例中诊断为双耳前庭水管扩大者10例(3.2%),其中语前聋7例,语后聋3例。回顾性分析这10例患者的临床资料。结果 10例患者人工耳蜗电极植入顺利,8例耳蜗底回开窗时发生轻度井喷,迅速用颞肌筋膜牢固封闭圆窗制止井喷。全部患者术后未出现脑脊液漏、颅内感染、面瘫、中耳炎等并发症。开机6个月时8例患者具有开放性言语识别力,已进入普通学校(幼儿园、小学、大学)就读。另2例语前聋的幼儿视觉强化测听听阈达40dB HL,与其他无内耳畸形的全聋儿童术后效果差异无显著性。全聋前语言能力较好的5例患者术后语言能力明显好于语前聋的患者,语言交流基本听不出聋人特有的语音特征。另5例患者语言均有不同程度的进步。结论 尽管前庭水管扩大患者在人工耳蜗植入术中可能出现井喷,但术后未出现并发症且听力-言语康复效果好,因此重-极重度聋的前庭水管扩大综合征患者行人工耳蜗植入术是安全可行的。 相似文献
92.
Objective The study was to explore the safety, firmness and convenience of the fascia around the ischial spine as a new fixation site for the vaginal fornix. Methods Between June 2007 and January 2008, detailed dissections and related measurements of the regions around the ischial spine were performed on 10 Chinese female cadavers (3 unembalmed and 7 embalmed cadavers). At the same time, the sacrospinous ligament,the fascia on the ischial spine, the iliococcygeus fascia as well as the vaginal fornix were exposed and the pull-out strength sequentially tested using a digital push-pull force gauge. Results The fascia on the ischial spine was firm and strong, with a thickness of 3 about mm. No major vessels or nerves were observed on the ischial spine. The greatest pullout strengths of the sacrospinous ligament,the fascia on the ischial spine, the iliococcygeus fascia as well as the vaginal fornix were (102±26),(64±15),(33±8)and(32±6)N, respectively. Conclusion The fascia at 1 cm from anterior lateral ischial spine, free of major vessels and nerves, is safe and strong and could be used as a new site for suspension in vaginal prolapse. 相似文献
93.
The conduct of in vitro and in vivo drug-drug interaction studies: a Pharmaceutical Research and Manufacturers of America (PhRMA) perspective. 总被引:12,自引:0,他引:12
Thorir D Bjornsson John T Callaghan Heidi J Einolf Volker Fischer Lawrence Gan Scott Grimm John Kao S Peter King Gerald Miwa Lan Ni Gondi Kumar James McLeod R Scott Obach Stanley Roberts Amy Roe Anita Shah Fred Snikeris John T Sullivan Donald Tweedie Jose M Vega John Walsh Steven A Wrighton 《Drug metabolism and disposition》2003,31(7):815-832
Current regulatory guidances do not address specific study designs for in vitro and in vivo drug-drug interaction studies. There is a common desire by regulatory authorities and by industry sponsors to harmonize approaches, to allow for a better assessment of the significance of findings across different studies and drugs. There is also a growing consensus for the standardization of cytochrome P450 (P450) probe substrates, inhibitors and inducers and for the development of classification systems to improve the communication of risk to health care providers and to patients. While existing guidances cover mainly P450-mediated drug interactions, the importance of other mechanisms, such as transporters, has been recognized more recently, and should also be addressed. This article was prepared by the Pharmaceutical Research and Manufacturers of America (PhRMA) Drug Metabolism and Clinical Pharmacology Technical Working Groups and represents the current industry position. The intent is to define a minimal best practice for in vitro and in vivo pharmacokinetic drug-drug interaction studies targeted to development (not discovery support) and to define a data package that can be expected by regulatory agencies in compound registration dossiers. 相似文献
94.
DPC4/Smad4基因是新近被鉴定的一个肿瘤抑制基因 ,其编码的DPC4/Smad4蛋白是TGF β信号传导通路中的重要传导蛋白 ,是TGF β配体、受体结合后后续信号传导的胞质递质 ,参与TGF β受体激活后的信号传导。DPC4/Smad4调控的下游目的基因有p2 1WAF1、uPA、PAI 1、VEGF、TSP 1。转化生长因子 -β(transforminggrowthfactorbeta ,TGF β)信号传导通路的配体、受体、胞内信号传导分子Smad蛋白及其调控的下游目的基因等组成一个肿瘤生长的负性调节 ,通路中任何一个元件的异常都可引起信号传导紊乱 ,导致肿瘤发生 相似文献
95.
97.
BACKGROUND: Oxalate exposure produces oxidant stress in renal epithelial cells leading to death of some cells and adaptation of others. The pathways involved in these diverse actions remain unclear, but appear to involve activation of phospholipase A2 (PLA2) and redistribution of membrane phospholipids. The present studies examined the possibility that oxalate actions may also involve increased accumulation of ceramide, a lipid-signaling molecule implicated in a variety of pathways, including those leading to apoptotic cell death. METHODS: Ceramide accumulation was examined in renal epithelial cells from pig kidney (LLC-PK1 cells) and from dog kidney [Madin-Darby canine kidney (MDCK cells)] using the diacylglycerol kinase assay. Sphingomyelin degradation was assessed by monitoring the disappearance of 3H-sphingomyelin from cells that had been prelabeled with [3H]-choline. The effects of oxalate were compared with those of other oxidants (peroxide, xanthine/xanthine oxidase), other organic acids (formate and citrate), and a known activator of sphingomyelinase in these cells [tumor necrosis factor-alpha (TNF-alpha)]. Separate studies determined whether oxalate-induced accumulation of ceramide could be blocked by pretreatment with antioxidants [Mn (III) tetrakis (1-methyl-4-pyridyl) porphyrin (Mn TMPyP, a superoxide dismutase mimetic) or N-acetylcysteine (NAC; an antioxidant)], with an inhibitor of ceramide synthase [fumonisin B1 (FB1)] or with an inhibitor of PLA2 [arachidonyl trifluoromethylketone (AACOCF3)]. RESULTS: Oxalate exposure produced a significant time- and concentration-dependent increase in cellular ceramide. A reciprocal decrease in 3H-sphingomyelin was observed under these conditions. Increases in cellular ceramide levels were also observed after treatment with other oxidants (hydrogen peroxide, and xanthine/xanthine oxidase), activators of sphingomyelinase (TNF-alpha), exogenous sphingomyelinase, or arachidonic acid. Formate produced similar (albeit smaller) effects, and citrate did not. The oxidant-induced increases in ceramide were attenuated by pretreatment with NAC (a glutathione precursor) and MnTMPyP (a superoxide dismutase mimetic), suggesting a role for cellular redox states. The oxalate-induced increase in ceramide was also attenuated by pretreatment with AACOCF3, suggesting a role for PLA2. Pretreatment with FB1 produced a small but statistically insignificant attenuation of the response to oxalate. CONCLUSIONS: Oxalate exposure produces a marked accumulation of ceramide in renal epithelial cells by a process that is redox sensitive and mediated in part by activation of PLA2. Since cellular sphingomyelin decreased as ceramide increased, it seems likely that oxalate actions are mediated, at least in part, by an increase in sphingomyelinase activity, although alterations in ceramide synthase are also possible. Further study is required to define the steps involved in oxalate actions and to determine the extent to which ceramide signaling mediates oxalate actions. 相似文献
98.
Kobayashi N Ito M Nakamura J Cai J Cao C Hammel JM Fox IJ 《Transplantation proceedings》2000,32(7):2287-2288
99.
Emsley CL Gao S Li Y Liang C Ji R Hall KS Cao J Ma F Wu Y Ying P Zhang Y Sun S Unverzagt FW Slemenda CW Hendrie HC 《American journal of epidemiology》2000,151(9):913-920
The relation between trace element levels in drinking water and cognitive function was investigated in a population-based study of elderly residents (n = 1,016) in rural China in 1996-1997. Cognitive function was measured using a Chinese translation of the Community Screening Interview for Dementia. A mixed effects model was used to evaluate the effect of each of the elements on cognitive function while adjusting for age, sex, and educational level. Several of the elements examined had a significant effect on cognitive function when they were assessed in a univariate context. However, after adjustment for other elements, many of these results were not significant. There was a significant quadratic effect for calcium and a significant zinc-cadmium interaction. Cognitive function increased with calcium level up to a certain point and then decreased as calcium continued to increase. Zinc showed a positive relation with cognitive function at low cadmium levels but a negative relation at high levels. 相似文献
100.
目的:观察国产那法瑞林(nafarelin )长效制剂的长效作用及对大鼠垂体功能影响,并探讨其作用部位。方法:采用大鼠间质细胞睾酮 (RICT)法检测血清LH(luteinizing hormone)生物活性水平。结果:那法瑞林长效制剂在体内的持续释药时间为((40.0±6.8)d。单次理植3周后大鼠血LH的周期性分泌高峰及激发高峰均消失。预先理植长效制剂组大鼠血LH在切除双侧卵巢后变化不明显。结论:那法瑞林长效制剂确有长效作用,其通过作用于垂体而抑制大鼠垂体功能。 相似文献