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51.
HPLC测定益肤霜中红霉素和地塞米松的含量 总被引:5,自引:0,他引:5
采用HPLC测定益肤霜中红霉素和地塞米松的含量,控制制剂的质量。色谱条件:固定相为Kromasil C18柱;流动相为乙腈-0.2mol/L醋酸铵-水,流速0.8ml/min;检测波长215nm。以c对峰面积A作直线回归,红霉素在1.5-24g/L地塞米松在20-300mg/L的范围内,其浓度与峰面积呈直线关系。红霉素回收率为99.69%;地塞米松的回收率为100.28%。本法操作简便,结果准确, 相似文献
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Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals. 相似文献
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Duyn JH van Gelderen P Talagala L Koretsky A de Zwart JA 《Journal of magnetic resonance imaging : JMRI》2005,22(6):751-753
Measurement of brain perfusion using arterial spin labeling (ASL) or dynamic susceptibility contrast (DSC) based MRI has many potential important clinical applications. However, the clinical application of perfusion MRI has been limited by a number of factors, including a relatively poor spatial resolution, limited volume coverage, and low signal-to-noise ratio (SNR). It is difficult to improve any of these aspects because both ASL and DSC methods require rapid image acquisition. In this report, recent methodological developments are discussed that alleviate some of these limitations and make perfusion MRI more suitable for clinical application. In particular, the availability of high magnetic field strength systems, increased gradient performance, the use of RF coil arrays and parallel imaging, and increasing pulse sequence efficiency allow for increased image acquisition speed and improved SNR. The use of parallel imaging facilitates the trade-off of SNR for increases in spatial resolution. As a demonstration, we obtained DSC and ASL perfusion images at 3.0 T and 7.0 T with multichannel RF coils and parallel imaging, which allowed us to obtain high-quality images with in-plane voxel sizes of 1.5 x 1.5 mm(2). 相似文献
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An in vitro is described that attempts to detect patients with a potential for adverse systemic reactions to contrast material. This test involves measuring the rate of conversion of prekallikrein to kallikrein under certain standard conditions. In a preliminary retrospective study, the test could be used to identify such patients with a sensitivity of 88%, a specificity of 82%, and a predictive value of 79%. 相似文献
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Duyn A Van Eijkeren M Kenter G Zwinderman K Ansink A 《Acta obstetricia et gynecologica Scandinavica》2002,81(4):351-355
BACKGROUND: Only a small proportion of cervical cancer recurrences is detected during routine follow-up. We investigated which percentage of recurrences is detected during follow-up, which diagnostic tools are helpful to detect recurrent disease and which factors are of prognostic significance once recurrent disease has been established in patients treated for cervical cancer stage IB-IVA. METHODS: Characteristics of the primary tumor, characteristics of recurrent disease and follow-up were collected retrospectively from clinical records of 277 patients who achieved a complete remission of at least 3 months after primary treatment for cervical cancer in 1992, 1993 and 1994 in three university hospitals in the Netherlands. RESULTS: Of 277 patients, 47 (17%) developed recurrent disease; this was most often detected after self-referral (45%), and in 32% during routine follow-up. Survival did not differ significantly between these two groups. The presence of symptoms (87%) was the most important first abnormal test result leading to diagnosis of recurrence. In univariate analysis, disease-free interval (DFI) and treatment modality were significant prognostic factors for crude survival of recurrence. However, treatment modality varied considerably and the subgroups were small. Therefore, multivariate analysis was not feasible and clinically valid conclusions could not be drawn. CONCLUSIONS: In only 32% of all cases, recurrence was detected during a scheduled follow-up visit. In the majority of patients, recurrent cervical cancer was detected by symptoms (87%). In recurrent disease, DFI was a prognostic factor for survival. 相似文献
59.
Duyn A Van Eijkeren M Kenter G Zwinderman K Ansink A 《Acta obstetricia et gynecologica Scandinavica》2002,81(8):759-763
BACKGROUND: Only a small proportion of cervical cancer recurrences is detected during routine follow-up. We investigated which percentage of recurrences is detected during follow-up, which diagnostic tools are helpful to detect recurrent disease and which factors are of prognostic significance once recurrent disease has been established in patients treated for cervical cancer stage IB-IVA. METHODS: Characteristics of the primary tumor, characteristics of recurrent disease and follow-up were collected retrospectively from clinical records of 277 patients who achieved a complete remission of at least 3 months after primary treatment for cervical cancer in 1992, 1993 and 1994 in three university hospitals in the Netherlands. RESULTS: Of 277 patients, 47 (17%) developed recurrent disease; this was most often detected after self-referral (45%), and in 32% during routine follow-up. Survival did not differ significantly between these two groups. The presence of symptoms (87%) was the most important first abnormal test result leading to diagnosis of recurrence. In univariate analysis, disease-free interval (DFI) and treatment modality were significant prognostic factors for crude survival of recurrence. However, treatment modality varied considerably and the subgroups were small. Therefore, multivariate analysis was not feasible and clinically valid conclusions could not be drawn. CONCLUSIONS: In only 32% of all cases, recurrence was detected during a scheduled follow-up visit. In the majority of patients, recurrent cervical cancer was detected by symptoms (87%). In recurrent disease, DFI was a prognostic factor for survival. 相似文献
60.
Excel97在药物分析中的应用 总被引:1,自引:0,他引:1
目的:在药物分析中,电子表格软件MicrosoftExce197for Windows。方法:利用Excel的数据处理功能,进行药物的图表绘制、数据计算和统计处理,回归分析,特别是计算分析,并可建立分析数据库。结果和结论:Excel操作简单,功能强大,数据分析工作直观。 相似文献