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EVA ÅKERLÖF B. FREDRICSON O. GUSTAFSSON A. LUNDIN† N. O. LUNELL L. NYLUND L. ROSENBORG Å. POUSETTE 《International journal of andrology》1987,10(5):663-669
Two methods of separating human sperm were compared using twenty-two semen samples. The sperm were separated by a swim-up technique or by self-migration on a Percoll gradient followed by medium change. After separation, the sperm obtained were assessed for progressive motility, ATP content, energy charge index ([ATP + 0.5 ADP]/[ATP + ADP + AMP]) and morphology. In general, and especially for semen samples containing less than 20 X 10(6) sperm/ml, separation by Percoll gradient selected sperm that were superior to those separated by the swim-up technique. The relatively high energy charge index (greater than 0.8) showed that the sperm tolerated the separation conditions well. It is suggested that self-migration on a Percoll gradient should prove useful for obtaining sperm of high quality. 相似文献
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S. Vemuri 《Chemical biology & drug design》2005,65(4):433-439
Abstract: Precise determination of the peptide content in drug substance samples depends highly upon the particular peptide compound and methodology used. Four independent methods were evaluated and compared to determine which would produce the best experimental precision for analysis of thymalfasin (thymosin α‐1). Four different methods were evaluated including elemental analysis (CHN), quantitative amino acid analysis (AAA), high‐performance liquid chromatography (HPLC), and Kjeldahl. This study demonstrates that the AAA method is highly variable in one laboratory while quite precise in another laboratory. Similarly, HPLC results depended on the laboratory conducting the study with more precise values obtained under cGMP. On the contrary, the CHN method yielded highly precise [i.e. <2% coefficient of variation (CV)] values. As precise knowledge of protein content is fundamental for the compounding of final pharmaceutical product of a specific potency, the CHN analysis is recommended for peptide content determination of the drug substance thymalfasin. 相似文献
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Fengxiu Ouyang Binyan Wang Lester M. Arguelles Xiping Xu Jianhua Yang Zhiping Li Liuliu Wang Xue Liu Genfu Tang Houxun Xing Craig Langman Xiaobin Wang 《Archives of osteoporosis》2007,2(1-2):29-43
Summary We prospectively examined bone growth patterns in 894 children aged 6–17 years at the baseline visit, with a 6-year follow-up.
Results show bone “tracking” over a six-year interval and sexual dimorphism of bone attained levels and timing of peak bone
growth. Our findings underscore childhood and adolescence as critical periods for building bone and developing gender differences.
Introduction Bone growth patterns were prospectively examined in 894 Chinese children (496 males), aged 6–17 yrs, from a population-based
twin cohort. Whole-body bone area (BA), bone mineral content (BMC), and bone mineral density (BMD) were measured by DEXA at
baseline and a 6-yr follow-up.
Methods Graphic smoothing plots and generalized estimating equations were used to model bone attained levels, growth, and “tracking”.
Results Attained levels of BMC and BA increased curvilinearly with age. Male attained levels were higher than females after age ∼15 yr,
but BMD was lower between 13–17 yrs (Tanner stage I to IV). In both genders, peak BMC and BMD growth lagged ∼2 yrs behind
peak BA growth, which lagged 2 yrs behind peak height growth. Peak bone growth occurred 1–3 yrs later in males. Over the 6-yr
follow-up, all bone measurements “tracked”, but “shifting” across ranks also occurred, and baseline tertile ranking influenced
bone growth. Females with early menarche had higher attained levels than females with late menarche at age 12–13 yrs.
Conclusion Our findings confirm and expand previous studies on peak bone growth conducted in Caucasian cohorts, particularly sexually
dimorphic and maturational effects. The significant “tracking” of bone measurements in this 6-yr follow-up study underscores
the importance that osteoporosis prevention should begin in childhood and adolescence.
Fengxiu Ouyang and Binyan Wang contributed equally to this article.
Source(s) of support: This study is supported in part by grant R01 HD049059, R01 HL0864619 and R01 AR045651 from the National
Institute of Health and by the Food Allergy Project. 相似文献
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接触镜与泪液形态关系的临床评价 总被引:1,自引:0,他引:1
目的 :观察配戴不同种类接触镜后眼表面泪膜的形态、稳定性及泪液量的变化。方法 :对日戴SCL、RGPCL和Ortho KCL的 2 14名近视患者 4 2 8只眼 ,利用表面泪膜观察装置 (DR 1)观察戴镜前后眼表泪液膜和戴镜状态下镜上泪液膜的形态分级 ,同时测定泪膜破裂时间 (BUT)。利用酚红染色棉丝测定SCL戴镜前后的泪液量 ,并用折射仪 (AtagoCL 1)测量SCL含水量的变化。结果 :SCL配戴者随戴镜时间延长 ,BUT明显缩短 (P <0 .0 1) ,RGPCL和Ortho KCL配戴者戴镜 5年以内 ,BUT无明显变化 (P >0 .0 5 )。戴镜后RGPCL ,Ortho KCL和非戴镜正常眼三组间眼表泪膜分级比例差异无显著性 ,SCL组Ⅰ级比例为 6 .5 % ,显著低于其他组(16 .1%~ 2 3.0 % )。镜上泪膜 ,SCL、RGPCL和Ortho KCL三组均以Ⅳ级为主 (分别占 5 4 .4 %、5 3.4 %和 5 1.5 % ) ,SCLⅠ级比例仅 1.9% ,显著低于另二组 (分别占 6 .2 %和 12 .4 % )。SCL配戴者随戴镜时间延长 ,泪液量轻度减少 ,SCL含水量在戴镜 1w后即显著降低。结论 :科学配戴接触镜对泪液膜质量无明显影响 ,但SCL长期使用可能对泪膜有一定干扰作用。 相似文献
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应用双光子及单光子吸收测定技术,检测了92名出生3d内的新生儿骨矿质含量,其中巨大儿30名,正常体重儿32名,低出生体重儿30名,其孕龄分别是40.1±0.7、39.1±1.5和37.4±1.2孕周。结果表明,巨大儿、正常体重儿、低出生体重儿的全身骨矿质含量分别是101.6±28.8、85.2±19.8、59.9±27.2g/cm2,巨大儿骨矿质含量最高,正常体重儿次之,低出生体重儿最低,差异有显著性(P<0.01)。颅骨、肱骨、股骨的骨矿质含量与全身的骨矿质含量有高度的相关性,相关系数分别是0.943、0.879和0.745(P<0.01)。全身的骨矿质含量与出生体重、孕龄及头围有高度相关性,相关系数分别是0.755、0.596和0.556(P<0.01)。提示颅骨、肱骨及股骨的任一部位均可代表全身的骨矿质含量,肱骨是确定全身骨矿质含量较好的部位,新生儿骨矿质含量受出生体重、孕龄及头围的影响较大。 相似文献
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We assessed the mechanics and morphology of the lung in 165 rats treated neonatally with either room air (RA), O2, RA + steroids, or O2, + steroids. Newborn Sprague-Dawley male rats were randomly assigned to these groups. O2,-exposure (0.96-1.0 FiO2 lasted 5 days, and dexamethasone treatment consisted of eight daily S.C. injections of drug or buffer in successive doses of 0.5,0.4.0.3,0.2,0.1, 0.1. 0.1. and 0.1 mg/kg. At 58 days, right ventricular systolic pressure (RVP) was measured. At 60 days, all rats were sacrificed for obtaining lung weight and DNA, saline pressure-volume (P-V) curves, and morphometry. We weighed right ventricles (RV) and left ventricles + septa (LV). Hyperoxia alone did not, but steroid decreased survival rate to 79.4% (95.3% in RA rats, P < 0.02). Only 21 of 40 (52%) O2 + steroids rats survived, less than in both RA groups (P < 0.001). RV weight, RVP and muscularization of alveolar duct arteries were significantly increased in O2 vs. RA rats. In RA + steroids rats, weight of the LV was decreased but RV, RVP, and lung vasculature were not affected. These effects were additive in the O2 + steroid group. Wet lung weights and DNA were increased for RA + steroid rats over all others. O2 and steroids shifted the P-V curve to the left and O2+ steroids still further. Maximal lung volume increased significantly with RA + steroids and still further in O2 + steroids but not in O2 alone. O2 and steroids significantly increased the mean linear intercept and O2 + steroids even more so. In O2- and steroid-treated rats, the parenchymal air space increased. In conclusion, both neonatal hyperoxia and steroid administration caused aberrations in the growth of lung and connective tissue. The effects of the two were additive. The vascular system, maximal lung volume, and DNA responded differently, presumably by different modes of action. Pediatr Pulmonol. 1993; 16:81–88. © 1993 Wiley-Liss, Inc. 相似文献
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本文用气相色谱法对居住福州、长乐、宁化三个地区270名健康人群发铬含量进行调查。结果表明:福州地区发铬值高于其它两地区,并有非常显著性差异。总体发铬算术平均数与国内外部分地区所报导的结果比较接近,但在性别及年龄间差异不明显。对三个地区发铬值与当地土壤铬含量进行相关分析,r=0.9978,二者呈正相关,并有非常显著性意义。 相似文献