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51.
Nishard Abdeen Albert Cross Gregory Cron Steven White Thomas Rand David Miller Giles Santyr 《Magnetic resonance in medicine》2006,56(2):255-264
We used the dual capability of hyperpolarized 129Xe for spectroscopy and imaging to develop new measures of xenon diffusing capacity in the rat lung that (analogously to the diffusing capacity of carbon monoxide or DLCO) are calculated as a product of total lung volume and gas transfer rate constants divided by the pressure gradient. Under conditions of known constant pressure breath-hold, the volume is measured by hyperpolarized 129Xe MRI, and the transfer rate is measured by dynamic spectroscopy. The new quantities (xenon diffusing capacity in lung parenchyma (DLXeLP)), xenon diffusing capacity in RBCs (DLXeRBC), and total lung xenon diffusing capacity (DLXe)) were measured in six normal rats and six rats with lung inflammation induced by instillation of fungal spores of Stachybotrys chartarum. DLXeLP, DLXeRBC, and DLXe were 56 +/- 10 ml/min/mmHg, 64 +/- 35 ml/min/mmHg, and 29 +/- 9 ml/min/mmHg, respectively, for normal rats, and 27 +/- 9 ml/min/mmHg, 42 +/- 27 ml/min/mmHg, and 16 +/- 7 ml/min/mmHg, respectively, for diseased rats. Lung volumes and gas transfer times for LP (TtrLP) were 16 +/- 2 ml and 22 +/- 3 ms, respectively, for normal rats and 12 +/- 2 ml and 35 +/- 8 ms, respectively, for diseased rats. Xenon diffusing capacities may be useful for measuring changes in gas exchange associated with inflammation and other lung diseases. 相似文献
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54.
目的 探讨肺上沟癌的临床特点及放疗疗效和不良反应。方法 回顾性分析 3 3例肺上沟癌住院病人的临床特征和常规放疗的疗效。结果 肺上沟癌占原发性支气管肺癌的 2 9% ,常见症状为 :患侧肩、背和上肢疼痛 ( 78 8% ) ,后 1,2 ,3肋骨或椎骨破坏( 5 7 6% ) ,Horner’s综合征 ( 3 6 7% ) ;少见的症状为 :咳嗽 ( 2 7% ) ,咯血 ( 9% ) ;中位生存期为 8 4月 ;1,3 ,5年生存率分别为 3 5 6% ,12 3 % ,4 6% ;放疗反应可耐受。结论 肺上沟癌相当少见 ,其临床特征基本符合pancoast综合症 ,本病预后差 ,但放疗可缓解疼痛 ,提高生存质量。 相似文献
55.
Despite numerous studies of approach- and avoidant mindsets, relatively little research has addressed the impact of such motivational orientations on performance and emotion in a real-time, multi-task setting. A laboratory simulation is reported that examines the influence of an induced approach-centered, an avoidance-centered, and a “neutral” motivational mindset upon multiple aspects of task performance, self-regulatory cognition, and affect. Undergraduate females randomly assigned to one of three mindset conditions performed a simulated automobile drive across one practice and two experimental trials. Dependent measures included divided attention, behavioral indicators of driving “cautiousness” in relatively safe straight roadway sections as well as during more risk-filled driving, multiple aspects of self-regulatory thinking (including self-monitoring, intended effort, and self-administered consequences), and positive and negative affect. Results revealed that the avoidant mindset produced poorer executive attention (i.e., fewer correctly detected divided attention events), more “cautious” driving behavior and reduced performance variability (i.e., greater control) when driving on presumably safe, straight roadway sections, lower self-reports of intended effort, and greater negative affect relative to the approach mindset. Results are intepreted within a self-regulation-centered motivational framework. Implications of the multi-task simulation for the study of normal and disordered adjustment are considered. 相似文献
56.
机械通气治疗小儿急性肺损伤 总被引:1,自引:0,他引:1
目的:探讨小儿急性肺损伤(ALI)的临床治疗。方法:对本院综合ICU1998年4月至2002年4月发生的22例小儿ALI的临床治疗情况进行回顾性分析。结果:本组22例小儿ALI采用呼吸末正压机械通气(PEEP)联合大剂量甲基强的松龙冲击治疗,有效率为86.36%;3例死亡,死亡率为13.64%,死于多器官功能不全综合征(MODS)。结论:机械通气治疗小儿ALI应选择最佳PEEP,动态监测动脉血气指标和X线胸片,在综合治疗基础上加用大剂量甲基强的松龙冲击治疗能收到较好的疗效。 相似文献
57.
论我国医患冲突成因及和谐关系构建 总被引:6,自引:3,他引:3
目前我国医患之间的矛盾与冲突,实质上是新时期我国社会矛盾在卫生工作中的具体表现,反映了社会群体在经济状况、价值取向、角色意识、道德水平、法律法规等多方面的矛盾与冲突。和谐医患关系应是构建我国和谐社会的内容之一。和谐医患关系的构建需要完善的社会医疗保障体系建立、国家卫生行政管理加大、财政补偿合理投入、医疗服务质量提高、医学知识教育普及与提高、媒体理性传播、社会大众道德控制水平提升,法律法规完善等全方位的努力,有赖于医事主体双方及全社会的关注与通力改善。 相似文献
58.
D. J. Lederer S. M. Arcasoy R. G. Barr J. S. Wilt E. Bagiella F. D'Ovidio J. R. Sonett S. M. Kawut 《American journal of transplantation》2006,6(10):2436-2442
We previously reported poorer survival among non-Hispanic blacks and Hispanics with idiopathic pulmonary fibrosis (IPF) compared to non-Hispanic whites at our center. In the current study, we hypothesized that these disparities would exist in a nationwide cohort of wait-listed patients with IPF. We performed a retrospective cohort study of 2635 patients with IPF listed for lung transplantation between 1995 and 2003 at 94 transplant centers in the United States. The age-adjusted mortality rate was higher among non-Hispanic blacks [hazard ratio (HR) = 1.24, 95% confidence interval (CI) 1.06-1.45, p = 0.009] and Hispanics (HR = 1.29, 95% CI 1.06-1.56, p = 0.01) compared to non-Hispanic whites. These findings persisted after adjustment for transplantation, medical comorbidities and socioeconomic status. Worse lung function at the time of listing appeared to explain some of these differences (HR for non-Hispanic blacks after adjustment for forced vital capacity percent predicted = 1.16, 95% CI 0.98-1.36, p = 0.09; HR for Hispanics = 1.21, 95% CI 0.99-1.48, p = 0.056). In summary, black and Hispanic patients with IPF have worse survival than whites after listing for lung transplant. 相似文献
59.
董频 《山东医大基础医学院学报》2006,(4)
目的:运用软硬腭前移的手术方法扩大鼻咽下口,改善因鼻咽部狭小致阻塞性睡眠呼吸暂停综合征患者的呼吸暂停症状。方法:手术切除硬腭后份使其缩短、悬雍垂软腭成形并将软腭拉向前,扩大鼻咽下口。结果:患者术后自觉症状及客观评价疗效满意。结论:软硬腭前移鼻咽下口扩大显著改善鼻咽下口狭小导致的阻塞性睡眠呼吸暂停患者的症状。 相似文献
60.
N Simelela 《International journal of gynaecology and obstetrics》2006,94(3):292-300
Preventing unintended pregnancies through access to modern family planning could avert 20-35% of maternal deaths, saving the lives of more than 100,000 women each year. Obstacles to wider access still exist, but they may be overcome by overt policy commitment to reproductive health services, partnership between stakeholders, community involvement and quality programs. 相似文献