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101.
本文报道3-50岁214例心导纳微分环(CADL)和肺导纳微分环(PADL)最大向量振幅及方位正常值,结果随增龄变化振幅递减,方位递增,多数男>女,部分组间有差异。48例左向右分流先心病环体最大向量与肺动脉压之间呈平行关系,并探讨其临床意义。  相似文献   
102.
We describe a new respiratory valve system with minimal dead space, which allows measurement of ventilation and oxygen uptake during swimming. The device offers considerable advantages in efficiency and accuracy over current equipment, and can be used in conjunction either with a miniaturized telemetry system for oxygen uptake measurement or with a conventional system. The valve has a low airflow resistance, a small dead space (15 ml), and an electrically operating, closed-circuit pump to remove excess water from the expiratory tube. The external form and the buoyancy of the valve have been hydrostatically and hydrodynamically designed to reduce drag and to ensure a correct mass in the water. To obtain this result a very sophisticated material, carbon fibre, has been utilized. Our studies showed that this respiratory system is ideal for obtaining valid and reliable values of oxygen uptake during swimming, even at high speed and in endurance swimming tests.  相似文献   
103.
目的探讨PET-CT一体机在恶性肿瘤中的应用价值.方法收集已经明确诊断的全身不同部位的恶性肿瘤病例62例,经PET-CT检查后进行回顾性分析,采用目测和半定量分析方法.结果62例肿瘤病人共检出142个病灶,PET图像阳性率93.55%(58/62);PET图像阴性率6.45%(4/62);PET发现病灶而CT未完全发现病灶率19.4%(12/62);CT发现而PET未见浓聚率6.45%(4/62);原发灶未能找到率1.61%(1/62).标准化摄取值(SUV)大于2.5占78.2%(111/142);SUV2.5~2.0占14.8%(21/142);SUV小于2.0占7%(10/142).结论PET-CT与单纯PET,CT比较具有明显的优势,可以精确定位、定性,但PET-CT也有一定的局限性.  相似文献   
104.
中国社会主义政治文明建设是既要置于人类政治文明的背景之中 ,又要具有中国特色。政治文明建设价值选择是对政治文明发展趋向的整体确认 ,必须从政治理念、政治制度、政治行为、政治关系层面来把握。人类政治文明同质价值选择主要体现在权力制约、人民主权、治理方式 ;中国政治文明特质价值即社会主义定向和中国国情 ,这种价值选择体现在制度形态、治理形态、文化形态之中。  相似文献   
105.
The delayed cytotoxicity of the Multicentre Evaluation of In vitro Cytotoxicity (MEIC) reference chemicals was investigated in rat hepatoma-derived Fa32 cells. The cells were treated for 24 h with the test chemicals, and were than further cultured for 5 days in normal culture medium. The cytotoxicity was measured by the neutral red uptake inhibition, and the results were quantified by determining the NI50del. This is the concentration of test compound required to decrease the neutral red uptake with 50% compared with control cells. The results were compared with the acute NI50, the corresponding value measured immediately after 24 h treatment of the cells. On a total of 44 chemicals, nine showed delayed cytotoxicity (NI50del lower than or equal to NI50), 11 a probably delayed, and 24 no delayed cytotoxicity (NI50del more than 1.5×NI50). When the NI50del was compared with human toxicity, a correlation coefficient r2=0.761 was obtained. For the same series of 44 chemicals this correlation was clearly higher than that for human hepatoma-derived Hep G2 cells (r2=0.695). The Hep G2 assay was the best acute in vitro assay for the prediction of human toxicity within the MEIC study. Consequently, the delayed cytotoxicity assay on cultured Fa32 cells has the best prediction value so far obtained for the human toxicity.  相似文献   
106.
健康成人135例心率变异性时域分析   总被引:2,自引:0,他引:2  
目的:探讨国人心率变异时域分析各项指标的正常值。方法:应用清华-西安兰港监测系统对135例18~79岁健康成人连续24h动态心电图监测。结果:①心率变异性时域:SDNN、SDSD、SDANN、RMSSD、PNN50分别为129.52±27.25ms;21.18±8.20ms;114.78±26.84ms;31.36±12.67ms;8.50 ± 7.80ms,所测得正常值范围与国内外研究结果相似。②18~35岁组、36~59岁组,均与≥60岁组有非常显著的差异(P<0.01,或P<0.05)。③各年龄组男女间SDNN、SDSD、PNN50无显著差异(P>0.05),但SDANN男性较女性大(P<0.05);女性RMSSD较男性大(P<0.05)。结论:SDNN>100ms;SDSD>12ms;SDANN>87ms;RMSSD>18ms;PNN50>0.7%可作为HRV时域分析参考正常值。  相似文献   
107.
行列资料诊断试验预告值和准确度的一次性标化研究   总被引:1,自引:0,他引:1  
本文建立了行列资料诊断试验预告值和准确度的一次性标化方法,省去了标化过程理论样本Nt的设定和求有关理论值的计算过程,导出行列资料中标准化Ⅰ级阳性预告值和标准化Ⅱ级阳性预告值、标准化Ⅰ级阴性预告值和标准化Ⅱ级阴性预告值、标准化可疑预告值和标准化准确度的一次性标化公式。分析了标化与非标化预告值的关系及转化规律。  相似文献   
108.
目的探讨50岁以上正常人左室舒张期脉冲多普勒频谱的参数变化情况。方法选择一年半时间内受检的所有50岁以上正常人475例,按每10岁为一组分4组进行分析。受检者取左侧卧位,常规显示心尖四腔心切面,取样容积置于二尖瓣尖,使声束与二尖瓣血流方向夹角<15°,以连续三个心动周期的平均值分别测量E峰、A峰、E/A及E峰减速时间并统计。结果发现E峰高于正常值低限的例数、平均E峰血流速度以及E/A均随着年龄的增加而下降,E峰减速时间则随着增龄而增加。结论左室舒张期血流频谱的所有参数与年龄有显著的相关性,明显随着增龄而变化,并且有其规律性。  相似文献   
109.
Summary Since 1992, efforts have been made to combat onchocerciasis in Guatemala through mass distribution of ivermectin. The impact of the campaign is assessed by taking skin-snips from sentinel groups within selected communities. This method gives an estimate of the prevalence and intensity of infection, and thus the efficacy of the treatment. In some communities people are becoming reluctant to volunteer for skin-snipping, and so there is a need for an alternative technique that will give quantitative results. In most hyperendemic communities in Guatemala, biting blackflies are so ubiquitous that few people object to allowing 10 to 20 flies to engorge upon them. We examined data on the quantitative uptake of microfilariae by Simulium ochraceum before and after ivermectin distribution to see whether results similar to skin-snip data could be obtained. Counts of microfilariae ingested by S. ochraceum are compared to the numbers found in skin-snips from the same volunteers. In a group of 31 untreated infected persons, a skin-snip survey detected 64.5% positive, while feeding flies (vector microfilarial uptake, VmfU) detected 96.8%. Post-treatment, in a sample of 58 of whom 52 (89.7%) had a history of infection, both skin-snips and VmfU detected 54.2%. Vector blood meals contained more microfilariae than a mg of skin before treatment, but both recorded about equal numbers after treatment. When the data set was subdivided to compare samples taken at 2–3, 6–8 and 14–17 months post-treatment, the effect of ivermectin was still apparent at 6–8 months, but had virtually disappeared by 14 months post-treatment. A surprising observation was that the flies ingested fewer microfilariae from treated persons than was expected from the skin densities as estimated by skin-snip. This effect lasted for over 8 months, and could indicate that ivermectin has a greater effect on transmission than previously suspected. We conclude that VmfU could be used as an alternative to skin-snipping, and discuss the ethical implications.  相似文献   
110.
对甲状腺机能亢进症(甲亢)患者进行了临床辨证分型,同步观察甲皱微循环及检测TT_3 TT_4 FT_4I、吸~(131)碘率,探讨它们之间的关系。结果表明甲亢患者微循环积分明显高于对照组(P<0.01),但不同类型甲亢的血淤情况亦不相同。心肝火旺型的微循环积分低于气滞痰凝型和血瘀型,但TT_3、TT_4、FT_4I明显增高;气滞痰凝型居中;血淤型的微循环积分明显增高,但TT_3、TT_4、FT_4I低于其他两型。吸~(131)碘率三型间无差异(P>0.05)。  相似文献   
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