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61.
本文作者改进了辣椒中辣椒素含量的测定法。即通过增设洋品空白管以消除色素的干扰;改变 Na_2CO_3溶液的浓度以缓和其操作条件及防止在低温时产生沉淀。本改良法具有简便、快速和重现性好之优点。 相似文献
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农民工结核病健康教育效果评价 总被引:1,自引:0,他引:1
目的 探讨开展结核病健康教育对提高农民工相关知识知晓率和态度正确率的作用.方法 对重庆市南岸区农民工进行结核病相关知识的健康教育,教育方式是由专科医生进行专题讲座.健康教育讲座前后在同一现场统一发放问卷,并当场收回,对教育前后农民工的结核病相关知识作一一配对比较.结果 调查15项内容,其中有14项内容教育前后有显著性差异.教育前农民工结核病知识知晓率为67.5%,教育后知晓率为99.5%;正向态度报告率从教育前的44.1%提高到60.1%.结论 健康教育能提高农民工防治结核病知识知晓率和态度正确率,此方法值得推广. 相似文献
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全营养素混合液(TNA)在肠外营养的应用 总被引:2,自引:0,他引:2
脂肪乳剂、葡萄糖、氨基酸、电解质、维生素及微量元素按一定程序混合配成10种全营养素混合液。在4℃14天贮存期内,10种混合液的pH和渗透压变化不大,不同混合液在不同时期的脂粒平均直径变化为0.3135±0.1012μm~0.4813±0.1893μm,94.93%脂粒的直径<0.6μm,无直径>6μm的脂粒,细菌培养阴性。74例共输全营养素混合液1,796次,无不良临床反应和异常实验室检查结果;用1周以上者大都显示氮平衡改善,用2周以上者血清转铁蛋白和白蛋白浓度可有不同程度升高。 相似文献
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Lina P Theodorakopoulou P Lionel Sadowsky Alex Jacobson William Lacefield 《American journal of orthodontics and dentofacial orthopedics》2004,125(3):329-336
The objectives of this study were to evaluate and compare the shear bond strengths and bond failure locations of 2 currently available orthodontic ceramic brackets. Forty polycrystalline ceramic brackets (Clarity, 3M Unitek, Monrovia, Calif) and 40 monocrystalline ceramic brackets (Inspire, Ormco, Orange, Calif) were bonded to 80 extracted premolars with the same bonding system. All bonded specimens were placed in distilled water for 42 hours at 37 degrees C followed by thermal cycling for 700 complete cycles. Forty ceramic brackets, 20 of each type, were tested on a universal testing machine to determine the shear force levels required to debond them. Forty ceramic brackets were removed with the debonding pliers recommended by the manufacturers. All teeth were examined under an optical microscope, and the adhesive remnant index was used to assess the bond failure locations. The mean shear bond strength of the Clarity brackets was 21.67 +/- 5.19 MPa, and the mean shear bond strength of the Inspire brackets was 20.32 +/- 8 MPa. The mean shear bond strengths of both brackets were higher than those considered clinically optimal. Most of the brackets (85% of Clarity and 75% of Inspire) tested on the machine failed at the bracket-adhesive interface. One premolar bonded with an Inspire bracket had enamel fracture upon debonding. Most of the brackets (90% of Clarity and 95% of Inspire) debonded with pliers failed at the bracket-adhesive interface. No enamel damage was evident in any specimen when the brackets were removed with the appropriate pliers. The results indicate that the safest way to remove ceramic brackets with respect to reducing the chance of enamel damage is to use the debonding technique specifically designed for each. 相似文献
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OBJECTIVES: To examine the effect of individual patient factors (age, parity, body mass index, menstrual cycle, menopause, hormone replacement therapy, bladder neck position and urethral mobility) on the appearance of Doppler flow in urethral vessels, to investigate the association between the Doppler flow parameters and intrinsic urethral function, storage and voiding, and to explore differences in the urethral vasculature between subjects with and without urodynamic stress incontinence (USI). METHODS: Over a 4-year period we prospectively performed imaging studies in 355 women, including 244 who denied any lower urinary tract symptoms within the previous 3 months (Group A) and 111 who had had lower urinary tract symptoms (Group B). Studies included morphologic assessment and Doppler flow investigation of the lower urinary tract. Vascular flow velocity and vessel density in the urethral vasculature were measured. For women in Group B, multichannel urodynamic studies were also performed. RESULTS: The urethral vasculature has five main branches of vessels. Their appearance was not affected by the menstrual cycle or menopause except for those of the anterior vaginal vessel and anterior branch of the middle urethral vessel. Other than that of the posterior urethral vessel, in which there was a correlation with parity, the resistance index (RI) was not affected by individual patient factors. However, there was a correlation between the vascular index (VI) and individual factors such as age (r = -0.336, P = 0.002), body mass index (r = -0.287, P = 0.028), menopause (r = -0.402, P < 0.001), and hormone replacement therapy (r = 0.392, P = 0.027). Only the VI and RI of the posterior urethral vessel correlated significantly with the urethral pressure profile. In subjects with lower urinary tract symptoms, the appearance of the urethral vasculature on power Doppler imaging and the corresponding RI and VI values were not correlated with objective evidence of USI. CONCLUSION: Patient factors may affect specific Doppler flow parameters of the urethral vasculature, which are related to intrinsic resting urethral closure. There is no difference in the appearance of the urethral vasculature in subjects with or without USI. 相似文献