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31.
慢性阻塞性肺疾病呼吸驱动影响因素分析 总被引:1,自引:0,他引:1
目的:探讨慢性阻塞性肺疾病(COPD)病人呼吸驱动与肺功能、血气及静息能量代谢之间的关系.方法:26例COPD和21例正常对照者分别测定口腔阻断压P0.1、呼吸肌功能[最大吸气压(PIMAX)、最大呼气压(P EMAX)]、肺通气功能[努力肺活量(FVC)、一秒率(FEV,%)]、残气(RV/TLC)、弥散功能(DLCO)、静息能量代谢(REE)、呼吸商(RQ)、血气分析及Borg分级等.结果:COPD组P0.1和P0.1/PIMAX高于对照组(P<0.01).相关分析COPD组P0.1与PaO2、SaO2负相关(r分别为-0.62,-0.53,P均<0.05),而与PaCO2相关性不明显.Borg分级与P0.1正相关(r=0.63,P<0.05),P0.1与FVC、FEV1%、RV/TLC、DLCO以及RQ无相关性,P0.1/PIMAX与REE有正相关关系(r=0.41,P<0.05).结论:COPD呼吸驱动增高,不仅与PaO2,SaO2相关,还与静息能量代谢及Borg分级等相关. 相似文献
32.
Jingxin Tianming Gang Geoffrey Ashley Lei Stephen T.C. 《Computerized medical imaging and graphics》2007,31(8):656-664
The human brain cortex is a highly convoluted sheet. Mapping of the cortical surface into a canonical coordinate space is an important tool for the study of the structure and function of the brain. Here, we present a technique based on least-square conformal mapping with spring energy for the mapping of the cortical surface. This method aims to reduce the metric and area distortion while maintaining the conformal map and computation efficiency. We demonstrate through numerical results that this method effectively controls metric and area distortion, and is computational efficient. This technique is particularly useful for fast visualization of the brain cortex. 相似文献
33.
AIMS: Overweight is common during late puberty in female patients with Type 1 diabetes. The aim of this study was to examine the change in body composition from late puberty to early adulthood in such female patients in comparison with age-matched control subjects. METHODS: Eighteen females with Type 1 diabetes and 19 healthy female control subjects were recruited for a case-control study at the age of 16-19 years (baseline). Six years later, 16 of the diabetic females and 17 of the control subjects were re-examined (follow-up). Body composition was assessed by dual energy X-ray absorptiometry. RESULTS: Body mass index (BMI) and fat mass index (total fat mass/height2) were significantly higher at baseline in the diabetic patients than in the control subjects (26.4 +/- 2.6 vs. 23.9 +/- 3.7 kg/m2, P < 0.05, and 10.0 +/- 2.4 vs. 8.0 +/- 2.8 kg/m2, P = 0.04, respectively). At follow-up, these parameters still tended to be higher in the diabetic group (27.8 +/- 4.9 vs. 24.6 +/- 5.7 kg/m2, P = 0.09, and 11.8 +/- 5.6 vs. 8.7 +/- 4.9 kg/m2, P = 0.05, respectively). BMI at baseline was strongly correlated to BMI at follow-up in both diabetic patients (r = 0.60; P < 0.05) and control subjects (r = 0.83; P < 0.01). CONCLUSIONS: Increased fat mass in pubertal girls with Type 1 diabetes seems to persist in young adulthood. This study emphasizes the need for new strategies to prevent the development of overweight during puberty in diabetic girls. 相似文献
34.
营养缺乏及补充维生素A对大鼠肺巨噬细胞功能的影响 总被引:2,自引:0,他引:2
采用Wistar大鼠,从怀孕16天进行限食喂养直到生后45天,干预组从生后第36天及第42天分别给予维生素A灌胃,每次2000IU。结果表明,补充维生素A可明显增加大鼠的胸腺重量、肺巨噬细胞的数目、巨噬细胞的吞噬功能及NO-2的分泌。维生素A可部分纠正营养缺乏导致的免疫缺陷、胸腺萎缩,活化肺巨噬细胞功能,其作用机制有待于进一步研究。 相似文献
35.
36.
根据窑顶辐射率,内表面积和角系数的变化,窑顶,胸墙和玻璃液面温度的改变,以及火焰-窑顶-胸墙-玻璃液面四者之间的辐射热交换,阐明了熔窑蜂状窑顶的节能机理。用计算机通过实例计算,定量表明了蜂窝状窑顶的节能效果。 相似文献
37.
38.
T. A. Larnach S. J. Boyd R. C. Smart S. P. Butler P. G. Rohl T. H. Diamond 《Calcified tissue international》1992,51(4):255-258
Summary Reproducibility of lateral spine dual energy X-ray absorptiometry (LAT DEXA) scans using a Lunar DPX-L scanner was assessed in a cadaveric phantom and in patients. One hundred phantom measurements over 7 months demonstrated a longitudinal stability of 1.7% (coefficient of variation, CV). Additional scans were performed with the phantom rotated by up to 20° in each of the three orthogonal planes to assess the effects of variable patient positioning. Horizontal and vertical rotation of the spine had little effect on the estimated bone mineral density (BMD), however, axial rotation of greater than 8° led to errors in the BMD measurement. One hundred consecutive patients had two lateral scans performed within 1 month. BMD (range 0.10–1.6 g/cm2) was determined for each scan by one operator. Significant overlap from ribs and pelvis was often seen with L2 and L4 vertebrae but one vertebra (L3) could be measured in every case. Intraoperator and interoperator variability was assessed by three experienced operators, each analyzing 10 patients' scans on five separate occasions, and was found to be less than 1.1% for a single vertebra. BMD estimation of vertebral bodies and midslices by lateral DEXA scans (CV% of 3.8% and 4.6%) have a 95% confidence interval of 0.074 g/cm2 and 0.096 g/cm2, respectively for two vertebrae. This variability is due mainly to axial rotation, with operator variability, horizontal rotation, and vertical rotation having little effect on BMD estimation. 相似文献
39.
40.
目的探讨双向线性能量和负压控制及不旋转核技术在晶状体悬韧带脆弱的白内障超声乳化手术中应用的临床效果。方法对220例(233只眼)悬韧带脆弱的白内障患者,应用双向线性能量和负压控制系统的高负压低能量技术结合不旋转核超声乳化法行白内障超声乳化联合人工晶体植入术。记录术中能量和相对能量复合参数以及并发症发生的情况,同时观察术后早期(1周内)和晚期(9~26个月)的矫正视力以及并发症发生情况。结果术后视力有明显提高。术前即存在轻度晶状体脱位(悬韧带断离范围小于1/4圆周)的15只眼中3只眼术中发生悬韧带断离范围轻度扩大(扩大范围小于1/8圆周);其它手术前未发现晶状体脱位的218只眼中2只眼术中发生局限性(小于1/8圆周)悬韧带断离。术后早期角膜一过性轻度水肿35只眼,15.2%;前房少量出血5只眼,2.1%;轻微虹膜炎45只眼,19.3%;瞳孔欠圆16只眼,6.9%。术后晚期前囊膜混浊122只眼,52.4%;前囊口收缩综合症5只眼,2.1%;后囊膜混浊76只眼,32.6%;人工晶体移位13只眼,5.6%;视网膜脱离3只眼,1.3%。结论利用双向线性能量和负压控制系统的高负压低能量技术结合不旋转核超声乳化法能最大程度地减少对晶状体悬韧带的旋转力和牵拉力,同时还降低了超声能量对悬韧带的冲击力,可最大限度地避免悬韧带的离断。 相似文献