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91.
本文在研究分析了CMOSens质量流量计和控制器的基础上,研究设计了一套能与呼吸机周期同步且成比例地释放NO标气的NO输送系统,并用N O/NO 2电化学传感器连续监测治疗气中NO浓度和二氧化氮(NO 2)浓度。在NO治疗气浓度为20 ppm的情况下,通过整定系统软件参数后,呼吸机的吸气流量和NO供给流量的相位差为0,NO检测浓度相比较整定前的检测值平均增大2.15 ppm,更接近于NO设定浓度值,NO 2检测浓度≤0.2 ppm属于安全范围。结果表明经过整定后的系统系实现了和呼吸机周期同步地供给NO标气,并且提高了NO治疗气的精度、降低了NO由于被氧化而生成NO 2的可能性。 相似文献
92.
The purpose of this study was to investigate the time course of skeletal muscle adaptations resulting from high-intensity,
upper and lower body dynamic resistance training (WT). A group of 17 men and 20 women were recruited for WT, and 6 men and
7 women served as a control group. The WT group performed six dynamic resistance exercises to fatigue using 8–12 repetition
maximum (RM). The subjects trained 3 days a week for 12 weeks. One-RM knee extension (KE) and chest press (CP) exercises were
measured at baseline and at weeks 2, 4, 6, 8, and 12 for the WT group. Muscle thickness (MTH) was measured by ultrasound at
eight anatomical sites. One-RM CP and KE strength had increased significantly at week 4 for the female WT group. For the men
in the WT group, 1 RM had increased significantly at week 2 for KE and at week 6 for CP. The mean relative increases in KE
and CP strength were 19% and 19% for the men and 19% and 27% for the women, respectively, after 12 weeks of WT. Resistance
training elicited a significant increase in MTH of the chest and triceps muscles at week 6 in both sexes. There were non-significant
trends for increases in quadriceps MTH for the WT groups. The relative increases in upper and lower body MTH were 12%–21%
and 7%–9% in the men and 10%–31% and 7%–8% in the women respectively, after 12 weeks of WT. These results would suggest that
increases in MTH in the upper body are greater and occur earlier compared to the lower extremity, during the first 12 weeks
of a total body WT programme. The time-course and proportions of the increase in strength and MTH were similar for both the
men and the women.
Accepted: 6 September 1999 相似文献
93.
A simple device for fluid exchange is described, which allows the exchange of an unlimited number of solutions at low (10–1000 nl/min) constant perfusion rate. The applicability of the system has been tested in microperfusion experiments of rat distal tubules. At a luminal perfusion rate of 40 nl/min, the lag time was some 20 sec and 80 % fluid exchange time some 3 sec. Simple modification allows further reduction of the lag time. Under control conditions, the potential difference across the late distal tubule (PDte) approaches –19.4±2.5 mV (n = 27). Increase of luminal potassium concentration from 5.4 to 40 mmol/l hyperpolanzes PDte to –29.9±4.3 mV (n = 8). Amiloride (10 mol/l) leads to a reversible depolarization to –3.2±1.0 mV (n = 19), barium (1 mmol/l) to a reversible hyperpolarization to –25.8±2.6 mV (n = 19). As expected, PDte is largely created by amiloride sensitive sodium channels and is partially blunted by barium sensitive potassium channels. 相似文献
94.
41名肢残者十六项人格特质测验 总被引:1,自引:1,他引:1
张丹 《中国心理卫生杂志》1989,3(6):248-249,271
应用“卡特尔十六项人格特质测验问卷”,对41名肢残者和40名健全人进行对照研究。结果表明,肢残人较健全人在孤独性上具有明显的差异,偏于缄默,固执,关注外界信息,具有一定的防卫倾向。肢残人富于实验性,较健全人更自由、激进、好学,具有较强的独立工作能力,希望生活更充实多彩。在各项能力水平上,肢残上与健全人没有显著差别。不同性别肢残人人格特质在敏感性上差异明显,女性较理智和着重现实,而男性则偏于敏感,易感情用事。 相似文献
95.
The umbilical vascular bed of the rat placenta was perfused in situ. Ouabain (10–4M) in the perfusion fluid had no effect on the unidirectional flux of Na+ from the maternal (electrically negative) to the foetal (electrically positive) side of the placenta, or on the transplacental potential difference. This was taken to indicate that there is no significant active transport of Na+ across the placenta of the rat. 相似文献
96.
目的 通过食道心房起搏负荷试验 ,使用彩色多普勒超声心动图对左心室室壁运动状态及左心室舒缩功能改变进行评价 ,以提高冠心病诊断的检出率 ;方法 使用心脏程序刺激仪经食道起搏导管调整心率达次极量 ;同时使用彩色多普勒超声心动仪进行左心室室壁运动记分并记录二尖瓣口及主动脉瓣环部血流频谱 ;结果 经食道心房起搏增加心脏负荷 ,应用左心室每搏量 (SV)、主动脉瓣环部流速积分 (VTIAO)、等容舒张时间 (IVRT)、二尖瓣口流速积分(VTIMV) )、快速充盈分数 (RFI)及室壁运动记分指数 (WMSI)作为指标在冠心病诊断中可提高检出率 ,以WMSI结合其它两项左心室舒缩功能阳性指标 ,其冠心病诊断的检出率为 95 % ,假阳性率为 3% ;结论 经食道心房起搏彩色多普勒负荷超声心动图 (TPDE)在冠心病诊断中有较高的应用价值 ,因其简便、实用和安全 ,宜在临床广泛推广使用 相似文献
97.
he present study examined strain differences in the light-dark preference among four strains of rats. The test was done in the home-cage situation under 12L:12D cycles. Data from four strains were compared: BN/Kyo, BDIX/Nem, Wistar/Nu, and F344/NSlc. These strains differed in the light-dark preference measured by the ratio of the time spent in the field area of the home cage during the light period. BN/Kyo and BDIX/Nem spent the most time (approx. 23%) in the field during the light period, while F344/NSlc spent the least time (approx. 5%). Wistar/Nu fell between the two (approx. 12%).This study was conducted as partial fulfillment for the master's degree, submitted to Nagoya University by the first author. It was presented at the 47th Annual Conference of the Japanese Society of Animal Psychology. 相似文献
98.
目的:临床评价增殖性瘢痕的颜色需要定量测量.本实验主要研究增殖性瘢痕色度的测量方法,实现瘢痕颜色的定量测量,为临床诊治提供量化依据.材料与方法:采用以光电积分式测量原理设计的色彩分析仪对增殖性瘢痕患者19人,共65个测试点按不同部位分为四组进行色度测量,并与正常组对照.用CIE-XYZ色度标准表达测量值,配合色度图直接观察瘢痕的疗效.结果:增殖性瘢痕各部位组的色度坐标值与相应的对照组比较均有显著性差异(P<0.05).结论:本实验的测量方法是有效的,能准确、定量反映增殖性瘢痕颜色的变化.可用量化指标总结、分析、报告治疗结果. 相似文献
99.
序列解剖层片的全局和局部色彩校正 总被引:1,自引:0,他引:1
本研究提出了一种全局和局部相结合的序列解剖层片的色彩校正算法。利用数字人层片(中国女婴一号)上提供的彩色灰度卡对相邻层片间各颜色通道的色彩差异进行全局校正,以消除解剖数据集沿垂直方向的光照变化;再利用线性校正模型和差值图像各通道(R、G、B)的灰度局部直方图,对解剖数据集进行局部色彩差异校正。重建结果表明,经过全局和局部色彩校正后,重建视图中的明暗条纹基本消失,说明层片间颜色的不连续现象得到了校正。 相似文献
100.
A racial difference in apolipoprotein E allele frequencies between the Japanese and Caucasian populations 总被引:2,自引:0,他引:2
We have examined the apo E phenotype frequencies in the Japanese population (n = 576, 16-78 years of age). Apo E phenotypes were determined by the rapid flat gel isoelectric focusing method that we previously reported. The apo E phenotype frequencies in the Japanese were 0.3% for E2/2, 6.1% for E3/2, 71.9% for E3/3, 0.7% for E4/2, 19.3% for E4/3 and 1.7% for E4/4. The apo E allele frequencies were 0.037, 0.846 and 0.117 for the epsilon 2, epsilon 3 and epsilon 4 alleles, respectively. These frequencies were compared with those in the Caucasian populations (n = 3033) reported by Sing & Davignon (1985). There was a significant difference in the apo E phenotype frequencies between the Japanese and Caucasian populations. In addition, a significantly lower frequency of the epsilon 2 and epsilon 4 alleles and a significantly higher frequency of the epsilon 3 allele were found in the Japanese than those reported for the Caucasian populations. It is concluded that there is a racial difference in the apo E allele frequencies between the Japanese and Caucasian populations. 相似文献