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111.
Isocratic RP-HPLC method for rutin determination in solid oral dosage forms   总被引:1,自引:0,他引:1  
A rapid and sensitive assay for quantitative determination of rutin in oral dosage forms based on isocratic reversed phase high performance liquid chromatography (RP-HPLC) was developed and validated. Using a C(18) reverse-phase analytical column, the following conditions were chosen as optimal: mobile phase methanol-water 1:1 (v/v), pH 2.8 (adjusted with phosphoric acid), flow rate=1 mL min(-1) and temperature T=40.0 degrees C. Linearity was observed in the concentration range 8-120 microg mL(-1) with a correlation coefficient of 0.99982 and the limit of detection (LOD)=2.6 microg mL(-1), and limit of quantification (LOQ)=8.0 microg mL(-1). Intra- and inter-day precision were within acceptable limits. Robustness test indicated that the mobile phase composition and pH influence mainly the separation. The proposed method allowed direct determination of rutin in pharmaceutical dosage forms in the presence of excipients, but is not suitable for preparations where compounds structurally/chemically related to rutin may be present.  相似文献   
112.
The vasovagal reaction has been widely studied but its anatomic and physiological nature remains uncertain. The mechanisms underlying vasovagal reaction related to blood donation are not completely understood either. Does its occurrence depend on the blood donors' physical characteristics and health variables or psychological factors? On the basis that a psychological approach considerably prevents donor reactions, the effect of fruit juice ingestion was studied in a group of 1849 first-time high-school students as a simple strategy to avoid systemic reactions at blood donation. The reasons for the psychological effect of this hydration protocol are stressed also in light of previous physiological studies on the hemodynamic effects of water or carbohydrate drinks.  相似文献   
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IntroductionThe aim of this study was to investigate the allele and genotype frequencies of 8 human platelet antigen (HPA) systems among blood donors from the Blood Transfusion Institute of Serbia and to compare them with published studies. These data would be useful to establish the basis for a platelet apheresis donor registry.Material and MethodsSeventy-two unrelated male platelet apheresis/blood donors from Serbia were typed for 8 HPA systems (HPA-1 to HPA-6, HPA-9, and HPA-15) via the FluoGene method, based on polymerase chain reaction-sequence-specific amplification (PCR-SSP; PCR using sequence-specific primers) with fluorometric signal detection. Allele and genotype frequencies were estimated by direct counting and compared to the expected genotype frequencies according to the Hardy-Weinberg principle. The transfusion mismatch probability was calculated for every HPA specificity.ResultsThe allele frequencies were: HPA-1a, 0.868; HPA-1b, 0.132; HPA-2a, 0.917; HPA-2b, 0.083; HPA-3a, 0.611; HPA-3b, 0.389; HPA-5a, 0.903; HPA-5b, 0.097; HPA-9a, 0.993; HPA-9b, 0.007; HPA-15a, 0.472; and HPA-15b, 0.528. For HPA-4 and HPA-6 only allele a was detected.DiscussionThe HPA allele frequencies of European populations showed no significant differences in comparison with our results. Statistically significant differences were revealed in comparison with some populations of non-European origin. In the tested donors no HPA-2 bb genotype was detected, but we found 1 donor with the rare HPA-9b allele. The biggest transfusion mismatch probability in the Serbian population is for systems HPA-15 (37.4%) and HPA-3 (36.2%), which means that more than a third of random transfusions could cause mismatch in these systems. This study was enabled by the introduction of molecular HPA typing, and it provides initial results of the HPA allele and genotype frequencies in the population of blood donors in Serbia. They will be used to provide a compatible blood supply on demand for treating patients with alloimmune thrombocytopenic disorders. The successful implementation of PCR-SSP with fluorometric signal detection could be further complemented in the future by the introduction of high-throughput methods, which will largely depend on the available financial resources.  相似文献   
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Purpose :Women with ultrasonic evidence of polycystic ovaries are at higher risk of ovarian hyperstimulation syndrome (OHSS). We focused on investigating a possible association of the (TTTTA) n microsatellite polymorphism in the promoter of the CYP11A gene with OHSS during controlled ovarian hyperstimulation (COH). Methods :We evaluated 58 patients at high risk of OHSS (study group) and 58 control patients undergoing controlled ovarian hyperstimulation. Results :The difference in the allele distribution between both groups of patients was not statistically significant. The genotype distribution of 4+ (with at least one copy of the four-repeat-unit allele) and 4− (without the four-repeat-unit allele) genotypes was identical in the two groups. Conclusion :An association between the (TTTTA) n microsatellite polymorphism in the promoter of the CYP11A gene and the pathogenesis of OHSS could not be confirmed.The paper was presented in part at the European Human Genetics Conference 2004 (ESHG), in Munich, Germany at June 12, 2004.  相似文献   
116.
Objective: The aim of the study was to investigate which anamnestic, laboratory and ultrasound parameters used in routine practice could predict the nature of adnexal mass, thus enabling referral to relevant specialist. Methods: Study involved the women treated for adnexal tumors throughout a period of 2 years. On admission, detailed anamnestic and laboratory data were obtained, expert ultrasound scan was performed, and power Doppler index (PDI), risk of malignancy index (RMI) and body mass index (BMI) were calculated for all patients. Obtained data were related to histopathological findings, and statistically analyzed. Results: The study included 689 women (112 malignant, 544 benignant, and 33 borderline tumors). Malignant and borderline tumors were more frequent in postmenopausal women (P=0.000). Women who had benignant tumors had the lowest BMI (P=0.000). There were significant (P<0.05) differences among tumor types regarding erythrocyte sedimentation rate, CA125 and carcinoembryonic antigen (CEA) levels. Among ultrasound findings, larger tumor diameter and ascites were more frequent in malignant tumors (P=0.000). Women with malignant tumors had highest values of RMI and PDI (P=0.000). Conclusions: Anamnestic data, ultrasound parameters and laboratory analyses were all found to be good discriminating factors among malignant, benignant and borderline tumors.  相似文献   
117.
The use of 24-hour urinary sucrose and fructose as potential biomarkers for sugars consumption was investigated in two studies of 21 healthy participants living in a volunteer suite where dietary intake was known and all specimens collected. The dose-response was assessed in 12 males using a randomized crossover design of three diets containing constant levels of 63, 143, and 264 g of sugars for 10 days each. Both sugars and sucrose intake were significantly correlated with the sum of sucrose and fructose concentration in urine (0.888; P < 0.001). To assess effects with volunteers consuming their habitual varying diets, seven males and six females were fed their usual diet (assessed beforehand from four consecutive self-completed 7-day food diaries) for 30 days under controlled conditions in the volunteer suite. The mean (+/-SD) calculated total sugars intake was 202 +/- 69 g/d, 41% from sucrose. Mean (+/-SD) urinary sucrose and fructose were 36.6 +/- 16.6 and 61.8 +/- 61.3 mg/d, respectively. The sum of sucrose and fructose in urine was significantly correlated with sugars (0.841; P < 0.001) and sucrose intake (0.773; P = 0.002). In the regression, 200 g of sugars intake predicted approximately 100 mg of sucrose and fructose in urine. The correlation between individual means of randomized 16 days of sugars intake and 8 days of sugars excretion data (as used in validation studies) remained as high as that obtained with the means of 30-day measurements and the regression estimates were very similar. Twenty-four-hour urinary sucrose and fructose could be grouped into a new category of biomarkers, predictive biomarkers, that can be used in studies determining the structure of dietary measurement error in free living individuals and to relate sugars intake to disease risk.  相似文献   
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Background and purpose

To evaluate the oncological outcome of a three-implant high dose rate (HDR) brachytherapy (BRT) protocol as monotherapy for clinically localised prostate cancer.

Material and methods

Between February 2008 and December 2012, 450 consecutive patients with clinically localised prostate cancer were treated with HDR monotherapy. The cohort comprised of 198 low-, 135 intermediate- and 117 high risk patients being treated with three single-fraction implants of 11.5 Gy delivered to an intraoperative real-time, transrectal ultrasound defined planning treatment volume up to a total physical dose of 34.5 Gy with an interfractional interval of 21 days. Fifty-eight patients (12.8%) received ADT, 32 of whom were high- and 26 intermediate-risk. Biochemical failure was defined according to the Phoenix Consensus Criteria and genitourinary/gastrointestinal toxicity evaluated using the Common Toxicity Criteria for Adverse Events version 3.0.

Results

The median follow-up time was 56.3 months. The 60-month overall survival, biochemical control and metastasis-free-survival rates were 96.2%, 95.0% and 99.0%, respectively. Toxicity was scored per event with late Grade 2 and 3 genitourinary adverse events of 14.2% and 0.8%, respectively. Late Grade 2 gastrointestinal toxicity amounted 0.4% with no instances of Grade 3 or greater late adverse events to be reported.

Conclusions

Our results confirm HDR BRT to be a safe and effective monotherapeutic treatment modality for clinically localised prostate cancer.  相似文献   
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