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2.
本文报道八个双炔失碳酯类似物的小鼠抗早孕、抗着床试验结果,同时考查了生物活性与油水分布系数之间的关系,发现抗早孕活性与油水分布系数之间为线性相关。双炔失碳半琥珀酸酯的抗早孕效果优于已用于临床的双炔失碳丙酸酯。 相似文献
3.
336例创伤数据对中国人创伤评分权重系数的评价 总被引:1,自引:0,他引:1
目的为了评价国内对TRISS评分权重系数的修订,对336例创伤患者分别用国外权重和国内权重评定伤情后进行比较。方法336例采用TRISS法计算生存概率Ps,所需权重分别采用新近报道的国内权重和国外MTOS权重。Ps≥0.5预测生存,Ps<0.5预测死亡,将预测生死与实际生死结果进行比较。结果中国人权重在敏感性和区别度方面高于国外权重,误判率低于国外权重。结论中国人权重对中国人的创伤程度评估有价值,为进一步精确修订权重,建议建立大型中国人创伤数据库 相似文献
4.
Morphometrical procedures were used to quantitatively evaluate human oocytes and embryos in an IVF programme. The metaphase II oocyte was an irregular 3.5 x 10(6) microns 3 sphere of 1.05 coefficient of form. The ooplasmic volume of 1.4 x 10(6) microns 3 was reduced by 10% by fertilization. The zona pellucida behaved as a stable and almost spherical envelope of 1.8 x 10(6) microns 3 volume and 17 microns thickness. Through the first three cleavages, mean blastomere reduces 28.5% volume per division, evolving from an irregular spherical shape with 0.9 coefficient of form to an ellipsoid (0.8) at the 8-cell stage. The coefficient of diversity between sister blastomeres progressively moved from 1.4 to 1.6 during the first two (2n) cleavages. The coefficient of diversity also increased at 3-cell (2.2) and 6-cell (2.6) asynchronous divisions. Morphologically abnormal embryos showed some morphometrical differences. Embryos which successfully implanted and progressed to birth showed a higher coefficient of diversity between sister blastomeres. 相似文献
5.
K. -M. Braumann W. Kleemann U. Martens N. Maassen U. Maass W. Schmidt D. Böning 《Journal of molecular medicine (Berlin, Germany)》1988,66(9):397-403
Summary Parameters characterizing the hemoglobin oxygen affinity were determined in blood of 12 male patients suffering from arterial occlusive disease (AOD) of the legs and compared with data obtained earlier from healthy human subjects (controls). Due to a COHb content of 4.8%±2.2% in the cigarette-smoking AOD patients, the standard oxygen dissociation curve (ODC) was left-shifted, the half-saturation pressure (P50) amounted to 24.8±1.7 mmHg (3.30±0.23 kPa), although the 2,3-diphosphoglycerate concentration was increased to 15.3±1.7 µmol/g Hb. Correcting the effects of elevated COHb shifts the P50 to 26.3 mmHg (3.5 kPa) and increases the steepness of the ODC (Hill's n) from 2.79±0.27 to about 2.99, which is significantly different from controls. The Bohr coefficients after acidification of blood with lactic acid (BCLac) show high values at low oxygen saturations of hemoglobin (–0.50±0.04 in AOD patients, –0.32±0.04 in controls;P<0.05 at 10% SO2). The cause of the alterations in hemoglobin oxygen affinity may be a reduced mean erythrocyte age, but also the influence of unknown factors generated, e.g., from anaerobic muscle metabolism in AOD.Abbreviations AOD
Arterial occlusive disease of the legs
- BC
Bohr coefficient
- BCCO2
Bohr coefficient after acidification of blood with CO2
- BCLac
Bohr coefficient after acidification of blood with lactic acid
- DPG
2,3-Diphosphoglycerate
- ODC
Oxygen dissociation curve
- P50
Oxygen pressure when hemoglobin is half-saturated 相似文献
6.
Bavo Vanden Eynde Dirk Vienne Magda Vuylsteke-Wauters Dirk Van Gerven 《European journal of applied physiology》1988,57(4):430-434
Summary To determine the cardiorespiratory response to maximal exercise before, during and after the pubescent growth spurt, thirty boys were tested at yearly intervals over a period of six consecutive years. For each individual, peak height velocity (PHV) was determined. The age at PHV (¯X= 13.6 years) was taken as a standard of maturation. The results from all subjects at 1.5 and 0.5 years before and 0.5 and 1.5 years after PHV are presented. The highest oxygen uptake (
) obtained during an incremental bicycle ergometer test to voluntary exhaustion was taken as peak oxygen uptake (
peak). Across each of the four years studied, mean
peak (min=49.6; max=52.5 ml·kg–1·min–1) and mean heart rate (HR) at
peak (min=190; max=192) did not change significantly as a function of PHV. On the other hand, the respiratory quotient at
peak increased considerably from mean minima and maxima of 0.99 and 1.01 before PHV to 1.07 and 1.10 after PHV. Ventilatory equivalent for
(
), taken as an indicator of ventilatory economy, seemed to be unaffected by the maturation process. The steepest increase in circumpubertal oxygen pulse was found one year after PHV. Average stability coefficients (¯r), calculated from the inter-years correlations were high for height (¯r=0.95), weight (¯r=0.92), HR at
peak (¯r=0.74),
peak in 1/min (¯r=0.71), oxygen pulse (¯r=0.68) and tidal volume (¯r=0.64). 相似文献
7.
目的明确人SR-AI转基因小鼠的一些形态、脏器、血液学和血浆脂质参数,为人SR-AI转基因小鼠模型的应用提供相关依据.方法用游标卡尺和电子称量天平测量人SR-AI转基因小鼠的吻长、眶间距、体长、尾长及12个脏器系数并与C57BL/6J小鼠进行比较分析;用SysmexK-4500型全血自动多参数血液分析仪检测其血液学指标;并用酶法分别测定血浆总胆固醇、甘油三酯和高密度脂蛋白胆固醇含量.结果人SR-AI转基因小鼠外部形态指标和脏器系数与C57BL/6J小鼠比较差异没有显著意义(P>0.05);转基因小鼠的各项血液学指标无明显改变,血脂蛋白成分的改变亦未显示统计学意义(P>0.05),甘油三酯的浓度略有增高(P<0.05).结论人SR-AI转基因小鼠的外部形态指标、脏器系数及各项血液学指标均无明显改变,适合用作动脉粥样硬化模型的研究. 相似文献
8.
加权关联度评价计划免疫工作质量 总被引:3,自引:0,他引:3
目的 :探求客观定量、准确可行、简便易行、能反映计划免疫工作质量全貌的综合评价方法。方法 :采用加权关联度分析对达州市 2 0 0 2年计划免疫监测结果进行评价。结果 :求得达州市 7个县市计划免疫监测结果的加权关联度值 ,列出其频数分布 ,估计回归方程 r=- 0 .3175 0 .185 7y,r=0 .995 3,差异有显著性意义 (P<0 .0 5 ) ,经合理分档 ,得出计划免疫工作质量优秀的县市 3个 ,中等的 3个 ,较差的 1个 ,符合实际情况。结论 :加权关联度分析能直观、定量、简明、准确地反映计划免疫工作质量 ,适用于计划免疫工作质量的综合评价。 相似文献
9.
In contrast to other reliability estimates, test-retest reliability (or reproducibility) captures not only the measurement error of an assessment instrument, but also the stability of the construct measured. Consequently, one would expect any departure from identity (Y = X) of measurement pairs (X first, and Y second measurement) to be treated as 'error' by the respective reproducibility statistic, even if 'true' changes happened, e.g. worsening of a disease due to its natural course. The Pearson correlation, still often advocated for continuous measures in test-retest reliability studies, however captures the degree of linearity (Y = bX + a): perfect relationship can be computed, even if the measurement pairs differ not only by a additive constant 'a', but also because of a multiplication of the X-values with the slope 'b'. Therefore, intraclass correlation coefficients (ICCs) have been proposed as alternative statistics for reproducibility. However, only ICCs with absolute agreement definition of concordance capture the degree of identity. ICCs with a consistency definition of concordance measure the degree of additivity (Y = X + a). ICCs are calculated from repeated measures analyses of variance (ANOVAs), and a common population variance must be is assumed for the different measurements. Given this assumption, an ICC computed from a one-way ANOVA seems to be the best choice for this purpose. Otherwise, Lin's concordance correlation coefficient is recommended as identity measure. 相似文献
10.
《Injury》2016,47(5):1072-1077
BackgroundSeveral studies have examined the relationship between injury volumes and trauma centre outcomes, with varying results attributable to differences in the measurement of volume's effect on mortality and differences in how characteristics are addressed as potential confounders.MethodsThis analysis includes all trauma cases reported to the NTDB 2012. The effect of trauma centre volume on patient mortality risk was measured in three different contexts: as a linear function of trauma centre volume, as a dichotomous function comparing patients in trauma centres with and without 1200 or more cases, and as a non-linear function of trauma centre volume. Multivariable weighted Hierarchical Generalized Linear Models were used to account for the combined effects of facility level and patient level covariates. Patient level mortality risk was assessed using the ACS Trauma Quality Improvement Programme methodology.ResultsTrauma centre volume was not a statistically significant predictor (at the α = 0.01 level) of patient mortality risk, in any of the three models. Comprehensive adjustments for patient level risk were obtained, with excellent discrimination between survivor and decedent cases. The addition of trauma volume to baseline patient mortality risk yielded no improvement in the accuracy of any model. These results were not sensitive to the inclusion of Level II trauma centres. Equivalent results were obtained by repeating the analysis for the Level I subpopulation only.ConclusionsCase volume may be a reasonable standard for determining whether adequate numbers of injured patients are available to support training needs and experience requirements of a Level I trauma centre. However, case volume is not a useful predictor of patient mortality in individual facilities. Trauma centre volume has no independent effect, after accounting for the patient level characteristics that predominantly influence mortality. 相似文献