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71.
This paper analyses the relationship between the thickness of the anterior femoral head cartilage (FHC), as measured by ultrasound, and some anthropometric parameters, such as height, weight, skeletal and chronological age. In addition, it provides standard norms for FHC thickness in a paediatric population. Both hips were examined in 213 consecutive subjects (99 boys and 114 girls), aged 1.9–14 years. Seventy-four subjects underwent hand and wrist X-rays for skeletal maturation: 32 of these were dropped from the study because a discrepancy as high as two standard deviations was found between their skeletal and their chronological age. The thickness of FHC correlated strongly with skeletal and chronological age, standing height and body weight. A side difference of 0.2 mm in FHC was considered to be abnormal. The study population was divided into 13 groups according to chronological age and values of FHC for boys and girls are provided for each group. It is suggested that the magnitude of hyaline FHC is a valuable feature in the evaluation of skeletal maturation in children. 相似文献
72.
73.
To study the biological effects of extremely low frequency (ELF) electric fields, a fundamental study is conducted of the human perception threshold of an electric field. The perception threshold is measured with human subjects, and the results are analysed. It is clear that field perception is based on the movement of hair and not on other sensations. Variance in the perception threshold and its causes are investigated. The perception threshold decreases by almost 30% as the relative humidity increases from 50 to 90%. The perception threshold is also dependent on the physical condition (length and density) of the hair and the psychological condition (degree of awareness) of the subject. The dependence on these is much smaller than that on relative humidity. The cause of the gender difference in the threshold is ascribed to the difference in the physical condition of the hair. Through this study, some factors to be taken into account for the safety standard are made clear. 相似文献
74.
目的:建立对甲苯咪唑微丸进行定性鉴别和含量测定的方法。方法:采用薄层层析法进行定性鉴别,用紫外分光光度法进行含量测定。结果:含量测定方法平均回收率为100.6% , R S D= 1.72% 。结论:所用方法简便可靠,可控制甲苯咪唑微丸的质量。 相似文献
75.
目的:评价血液透 析前注射单剂量低 分子量肝素( L M W H)与持续 输注普通肝素( S H)对复用透析器 效率的影响。方法:对 30 例慢性透 析患者进行随机交叉对照研究,观察第一、四次透析的透析器纤维包裹容量 ( F B V)、透析前血球压积 ( H C T)及透析 2 h 尿素氮、肌酐 清除率,另外,利用生色底物法测定透析 0 h、2 h、4h 血浆肝素抗 Fxa 水平。结果:同 S H 组比, L M W H 组透析器复用次数明显增加( P< 0.05),第四次复用透析器 F B V 及透析 2 h 尿素氮、肌酐清除 率无明显 下降( P< 0.05), S H 组则明显 下降( P< 0.05),透析 2 h 两组血浆肝素活性抗 Fxa 水平无明显差异( P< 0.05),透析 4 h L M W H 组明显高于 S H 组( P< 0.05)。结论:透析前 单剂量注射 L M W H 能保护复用透析器清 除率,值得临床上进一步推广。 相似文献
76.
R. D. Snee 《International archives of occupational and environmental health》1981,48(3):219-242
Summary An evaluation of the major studies of the effects of airborne lead on blood lead levels of male and female adult and child populations is presented. Analysis of these studies shows that the blood lead-air lead slope for adults is approximately 1.0 for both men and women. This implies that an exposure to an additional 1 g Pb/m3 of air can result in an increase of approximately 1 g Pb/100 ml of blood. The precision of the slope for adults is rarely better than ±0.5 to ±0.7 and can be as large as ±1.0. A large portion of this uncertainty in the calculated slope is due to blood lead measurement error. The slope of the blood lead-air lead response for children ranges from 0.7 to 1.4 and is approximately the same as that for adults. The accuracy of this number is less clear for children than adults due to the small data base. Many of the studies of children have been on populations living in the vicinity of smelters. It is questioned whether these data are representative of the air lead exposure of children living in urban and suburban communities. 相似文献
77.
We report our clinical experience with phototherapy in 3802 infants; 3629 were exposed to "standard" daylight phototherapy and 173 to "high-intensity" blue-light phototherapy. High-intensity blue-light phototherapy was twice as effective as standard daylight phototherapy in decreasing bilirubin concentrations. No failures occurred with high-intensity phototherapy compared with an overall failure rate of 1.84/1000 with daylight lamps; these cases were transferred to high-intensity phototherapy with prompt response. Rebound after cessation of phototherapy was greater in those exposed to high-intensity blue light with a significantly greater number requiring a second exposure. However, the incidence was still low. No third exposure was required in any infant. Nursing of infants under high-intensity blue light was more difficult and inconvenient as was clinical monitoring. The light also caused more stress on the nursing and medical personnel. However, the infants tolerated both types of phototherapy equally well. High-intensity blue-light phototherapy would seem to be the treatment of choice for infants with rapidly increasing or very high bilirubin levels, as well as in those not responding adequately to daylight phototherapy. 相似文献
78.
Information on premarital sexual attitudes of unmarried undergraduates was obtained from random samples on the same campus in 1968 and 1972. Students in 1972, compared with those in 1968, reported (1) more permissive attitudes toward premarital sexual behavior (both men and women), (2) fewer differences in attitudes between men and women, and (3) less adherence to the double standard. In contrast to earlier research on premarital sexual attitudes, these differences need not be due to the markedly different populations compared, or generalizable only to sociology and psychology students, or indicative of only those who chose to volunteer for study (volunteer bias).This research received support from the Institute for Research in Social Science and the University Research Council, University of North Carolina at Chapel Hill. 相似文献
79.
银菊清解片的质量标准研究 总被引:3,自引:0,他引:3
目的:建立了银菊清解片(野菊花,薄荷油,忍冬藤,对乙酰氨基酚等)的质量标准。方法:采用理化方法和薄层色谱法对银菊清解片的主要成分对乙酰氨基酚,马来酸氯苯那敏进行鉴别,并采用系数倍率法不经分离地直接测定对乙酰氨基酚的含量。结果:平均回收率为99.70%,RSD=0.83%(n=10)。结论:该法简便可行,结构准确,可用于该制剂的质量控制。 相似文献
80.