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21.
BACKGROUND: 13C breath test analysis requires accurate 13CO2 measurements. AIM:: To perform a multicentre study to evaluate the repeatability and reproducibility of breath 13CO2 analysis. METHODS: Two series of 25 paired randomly coded tubes (each consisting of 23 13CO2-enriched breath samples and two samples of standard reference pure CO2 with certified delta 13CPDB) were sent to participating centres for 13CO2 measurement. Each series of tubes was analysed 10 days apart. The repeatability and reproducibility of 13C measurements was assessed by Mandel's k and h statistics. RESULTS: Twenty-two centres participated in the study: 18 showed good inter- and intra-laboratory variability, whilst four showed abnormally high inter- or intra-laboratory variability. Breath test results were also significantly affected by the accuracy of the 13C analytical procedures. CONCLUSIONS: A low accuracy of 13C measurements may significantly affect the results of breath tests, leading to inappropriate clinical decisions. Standardization of 13C analysis is required to guarantee optimal 13C measurements and accurate 13C breath test results.  相似文献   
22.
目的建立炎琥宁原料药HPLC含量测定方法。方法采用Lnertsil ODS-3柱(5μm 250×4.6mm),乙腈—磷酸盐缓冲液45:55为流动相,检测波长251nm。结果炎琥宁在50~500μg范围内线性关系良好,相关系数为0.99997。平均回收率为99.39%(RSD为0.4)。结论本法简便、准确、灵敏度高、重现性好,可用于炎琥宁的质量控制。  相似文献   
23.
李静  原坤  徐建国 《黑龙江医药》2002,15(2):112-113
利用高效液相色谱法对3个批号,经3000LS强光照射不同时间的注射用羟氨苄青霉素钠进行稳定性测试,结果表明注射用羟氨苄青霉素钠在强光照射下不稳定,含量不断降低,但经3000LS强光照射10天内含量仍均在标准含量80%以上。  相似文献   
24.
Most of the purported links between microbial agents and primary small-vessel anti-neutrophilic antibody-positive (ANCA) vasculitides remain speculative. There is strong circumstantial evidence for the role of Staphylococcus aureus in the development of Wegener’s granulomatosis, but its role in other ANCA-positive vasculitis syndromes is less clear. We describe a patient who developed a non-granulomatous, necrotizing small-vessel vasculitis with a positive anti-neutrophil cytoplasmic antibody of a perinuclear type (p-ANCA), along with anti-myeloperoxidase antibodies after recurrent episodes of methicillin-resistant Staphylococcus aureus bacteremia.  相似文献   
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Indinavir plasma levels are associated with antiretroviral efficacy; however, little data are available regarding toxicity. We assessed the relationship between indinavir pharmacokinetic (PK) characteristics and severe nephrolithiasis as well as other severe or serious adverse reactions. Patients included in the ANRS CO8 APROCO-COPILOTE cohort and receiving 800 mg indinavir three times daily as a first-line protease inhibitor were eligible for this study. To be included in the analysis, their plasma sample at month 1 (M1) had to be available (n = 282) to estimate using population PK modeling, indinavir PK characteristics, ie, maximum (Cmax) and trough plasma (Cres) concentrations, area under the curve (AUC), and observed/predicted concentration ratio (CR). A Cox model was used to estimate the independent effect of Cmax, Cres, AUC, and CR on the hazard of severe nephrolithiasis and serious adverse reactions. At M1, median Cmax was 6205 ng/mL, Cres 631 ng/mL, AUC 24,242 ng . h/mL, and CR 0.6. After a median follow up of 12 months, 11% of patients (30 of 282) had experienced at least one serious adverse reaction among which 12 were nephrolithiasis. In the multivariate analyses, early high indinavir Cres (ie, >/=1000 ng/mL at M1) was associated with a higher rate of severe nephrolithiasis (hazard ratio = 6.7; 95% confidence interval = 1.8-25.2; P < 0.01) and was also associated with a higher rate of all serious adverse reactions but only when nephrolithiasis were included among those cases. Prospective and early indinavir Cres determination should be recommended in the patient's care management and dosage adjustments.  相似文献   
27.
Fixed-dose combination (FDC) therapy is recommended for hypertension management in Nigeria based on randomized trials at the individual level. This cluster-randomized trial evaluates effectiveness and safety of a treatment protocol that used two-drug FDC therapy as the second and third steps for hypertension control compared with a protocol that used free pill combinations. From January 2021 to June 2021, 60 primary healthcare centers in the Federal Capital Territory of Nigeria were randomized to a protocol using FDC therapy as second and third steps compared with a protocol that used the same medications in free pill combination therapy for these steps. Eligible patients were adults (≥18 years) with hypertension. The primary outcome was the odds of a patient being controlled at their last visit between baseline to 6-month follow-up in the FDC group compared to the free pill group. 4427 patients (mean [SD] age: 49.0 [12.4] years, 70.5% female) were registered with mean (SD) baseline systolic/diastolic blood pressure 155 (20.6)/96 (13.1) mm Hg. Baseline characteristics of groups were similar. After 6-months, hypertension control rate improved in the two treatment protocols, but there were no differences between the groups after adjustment (FDC = 53.9% versus free pill combination = 47.9%, cluster-adjusted p = .29). Adverse events were similarly low (<1%) in both groups. Both protocols improved hypertension control rates at 6-months in comparison to baseline, though no differences were observed between groups. Further work is needed to determine if upfront FDC therapy is more effective and efficient to improve hypertension control rates.  相似文献   
28.
目的构建SARS冠状病毒N蛋白的原核表达质粒,诱导重组蛋白表达并纯化,鉴定其抗原性。方法以我国SARS冠状病毒GDH株总RNA为模板,采用RT-PCR技术扩增N蛋白的全长基因,TA克隆后测序。构建pET-23d的N基因表达载体,用IPTG诱导目的蛋白表达,利用硫酸铵沉淀、分子筛层析及离子交换层析纯化重组蛋白,免疫印迹鉴定重组蛋白。结果RT-PCR扩增出1269bpSARS冠状病毒N蛋白的基因片段,其序列分析结果与SARS-CoVGD01、BJ01株的同源性为99.92%;该基因在大肠杆菌表达系统中高效表达,占可溶性蛋白的33.57%,表达产物为非融合的可溶性蛋白,Westernblot结果显示重组N蛋白具有良好的抗原性;纯化后重组N蛋白纯度为92.9%。结论成功构建了SARS冠状病毒N蛋白的重组表达质粒,并在大肠杆菌中以非融合蛋白的形式得到高效的可溶性表达,为SRAS的诊断和疫苗的研制奠定了基础。  相似文献   
29.
Hodgkin lymphoma (HL) incidence with HIV infection may have increased with the introduction of combination antiretroviral therapy (cART), suggesting that immune reconstitution may contribute to some cases. We evaluated HL risk with cART during the first months of treatment. With 187 HL cases among 64 368 HIV patients in France, relative rates (RRs) and 95% confidence intervals (CIs) of HL were estimated using Poisson models for duration of cART, CD4 count, and HIV load, with and without adjustment for demographic/clinical covariates. HL risk was unrelated to cART use overall, but it was related to time intervals after cART initiation (P = .006). Risk was especially and significantly elevated in months 1-3 on cART (RR 2.95, CI 1.64-5.31), lower in months 4-6 (RR 1.63), and null with longer use (RR 1.00). CD4 count was strongly associated with HL risk (P < 10??), with the highest HL incidence at 50-99 CD4 cells/mm3. With adjustment for CD4 count and covariates, HL risk was elevated, but not significantly (RR 1.42), in months 1-3 on cART. HIV load had no added effect. HL risk increased significantly soon after cART initiation, which was largely explained by the CD4 count. Further studies of HIV-associated HL are needed.  相似文献   
30.
ACCESSIBLE SUMMARY: ? The purpose of this study was to examine differences in substance use disorders, psychiatric disorders and nicotine dependence among 323 women and men accessing a smoking cessation programme in an addiction treatment setting in Vancouver, British Columbia, Canada. ? Individuals with substance use and psychiatric disorders have smoking prevalence rates nearly double that of the general population. Yet, there are distinct differences between men and women in their smoking behaviour and responses to smoking cessation treatment. Few studies have examined such sex differences among individuals with substance use and psychiatric disorders. ? The study found that compared with individuals with no psychiatric diagnosis, those with a mood, anxiety and psychotic disorders were significantly more likely to be female; whereas compared with those without a substance use disorder, individuals with alcohol, cocaine or marijuana disorder were more likely to be male. Moreover, among women having an anxiety disorder history and smoking a greater number of cigarettes per day were significantly associated with high nicotine dependence. Among men, smoking a greater number of cigarettes per day and having a lower confidence in quitting were significantly associated with high nicotine dependence. ? These findings suggest the need for appropriate assessment of smoking behaviour and nicotine dependence among individuals accessing addictions treatment services. Moreover, these findings further provide evidence of the need for tailored interventions for tobacco dependence among men and women with histories of substance use and psychiatric disorder. ABSTRACT: Most individuals in drug treatment programmes use tobacco and are dependent on nicotine. For 323 participants (65% men, mean age = 49.3 years) with a history of substance use disorder (SUD) and/or psychiatric disorders (PD) enrolled in a tobacco dependence clinic programme, we compared baseline characteristics among women and men and examined factors associated with nicotine dependence (ND). Individuals with mood, anxiety and psychotic disorders were more likely to be female, whereas men were more likely to be characterized by alcohol, cocaine and marijuana use, older age, older age at smoking initiation and higher confidence in quitting smoking scores. In stratified multivariate analyses, among women, history of an anxiety disorder and a greater number of cigarettes smoked per day were associated with higher ND scores; among men, a greater number of cigarettes smoked per day and higher confidence in quitting scores were associated with higher ND scores. Given the differences in smoking, SUD and PD histories between women and men accessing addiction treatment, and differential associations with ND, it is important to further explore factors that may enhance tailored treatments and inform future studies examining biological and psychosocial factors for tobacco use in SUD and PD treatment populations.  相似文献   
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