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991.
A simple spectrophotometric method for determination of glucosamine release from sustained release (SR) hydrophilic matrix tablet based on reaction with ninhydrin is developed, optimized and validated. The purple color (Ruhemann purple) resulted from the reaction was stabilized and measured at 570 nm. The method optimization was essential as many procedural parameters influenced the accuracy of determination including the ninhydrin concentration, reaction time, pH, reaction temperature, purple color stability period, and glucosamine/ninhydrin ratio. Glucosamine tablets (600 mg) with different hydrophilic polymers were formulated and manufactured on a rotary press. Dissolution studies were conducted (USP 26) using deionized water at 37+/-0.2 degrees C with paddle rotation of 50 rpm, and samples were removed manually at appropriate time intervals. Under given optimized reaction conditions that appeared to be critical, glucosamine was quantitatively analyzed and the calibration curve in the range of 0.202-2.020 mg (r=0.9999) was constructed. The recovery rate of the developed method was 97.8-101.7% (n=6). Reproducible dissolution profiles were achieved from the dissolution studies performed on different glucosamine tablets. The developed method is easy to use, accurate and highly cost-effective for routine studies relative to HPLC and other techniques.  相似文献   
992.
Transscleral diode laser therapy for cyclodialysis cleft induced hypotony   总被引:1,自引:0,他引:1  
In order to evaluate the efficacy of transscleral diode laser therapy for treatment of cyclodialysis cleft associated with ocular hypotony, transscleral diode laser therapy was used in two patients with cyclodialysis cleft. It was applied over the cleft area in two rows of 14 applications in a post-traumatic patient and of 8 applications in a post-trabeculectomy patient at a power setting of 2500 mW and duration of 2000 msec. The clefts were closed with restoration of normal intraocular pressure and recovery of visual function in both patients. Transscleral diode laser therapy seems to be a safe, simple and non-invasive method for closure of the cyclodialysis clefts, especially in patients inappropriate for argon laser photocoagulation and those with opaque cornea.  相似文献   
993.
Graft-versus-host disease (GVHD) is a common complication of allogeneic bone marrow transplantation (allo-BMT). Ocular surface disease (OSD) is one of the most common manifestations of chronic ocular GVHD, yet little is known about it. In this article, we review the available literature on this condition and present results from our study of the manifestations of OSD in the chronic phase (>3 months duration) post allo-BMT. Our study consisted of a retrospective chart review of 62 allo-BMT patients with chronic OSD evaluated at our center between 1995 and 2002. The clinical features, systemic associations, treatment, and status of OSD at the last follow-up are presented and discussed in the context of other reports of OSD in GVHD.  相似文献   
994.
995.
Prostaglandin E(1) (PGE(1)) has been used to treat pulmonary hypertension and peripheral artery occlusive disease and has been successfully employed for pharmacological bridging to transplantation in patients with chronic end-stage heart failure. In addition to its vasoactive effects PGE(1) was shown to stimulate angiogenesis in animal models. Recently we showed that PGE(1)-induced angiogenesis in hearts of patients with ischemic heart disease. We proposed that the angiogenic action of PGE(1) is mediated by vascular endothelial growth factor (VEGF). In the present paper we studied a possible effect of PGE(1) on the expression of VEGF-1 in cultured human adult cardiac myocytes (HACM) and cultured human adult cardiac fibroblasts (HACFB), respectively, to identify a cellular source of VEGF-1 in patients treated with PGE(1). We also aimed to delineate mechanisms involved in a possible regulation of VEGF-1 by PGE(1) in these cells. When HACM, isolated from human myocardial tissue, were treated with PGE(1), a significant up to 3-fold increase in VEGF-1 production could be observed. These results could be confirmed on the level of specific mRNA expression as determined by real-time polymerase chain reaction. The effect of PGE(1) on VEGF-1 expression could be blocked by H089, an inhibitor of cAMP-dependent protein kinase A. In HACFB, also isolated from human myocardial tissue, no effect of PGE(1) on VEGF-1 production was seen. If this effect of PGE(1) is also operative in the in vivo situation, one could speculate that cardiac myocytes could be a cellular source of PGE(1)-induced VEGF-1 expression in patients treated with this drug.  相似文献   
996.
997.
ObjectiveTo evaluate the preventive effect of neonatal circumcision on urinary tract infection and the incidence of complications following neonatal circumcision using Plastibell.Materials and methodsA prospective study was carried out between 2004 and 2008. During this period, there were 3000 neonatal circumcisions. All of the cases were examined for any complications 1 week later, and occurrence of meatal stenosis was followed up to 15 months of age. In this group, urine analysis and culture was successfully performed four times for 2000 circumcised infants at 1.5, 3, 9 and 15 months. In the control group of 3000 uncircumcised infants, 1000 cases accomplished urine analysis and culture at the same designated intervals.ResultsA positive urine culture was observed in none of the circumcised cases and in 20 (2%) uncircumcised cases after obtaining a suprapubic bladder aspiration sample. The latter 20 infants were circumcised and follow-up cultures were negative in 17 cases. The overall complication rate in the circumcised group was 1.6%. The difference in frequency of urinary tract infection between the two groups was statistically significant (P < 0.0001).ConclusionNeonatal circumcision has few complications and reduces the incidence of asymptomatic urinary infection. It may be considered as a preventative health measure.  相似文献   
998.

Objective

A study to validate and calibrate Pediatric Index of Mortality-2 (PIM2) in children admitted to our pediatric intensive care unit (PICU).

Methods

This is a prospective cohort study performed in Bahrami Children''s Hospital affiliated to Tehran University of Medical Sciences. We studied the patients admitted to PICU from May 2007 to November 2008. Clinical measures were identified upon arrival in PICU. We used PIM2 score and logistic regression analysis to compare expected mortality risk with observed mortality rate. Receiver operating characteristics (ROC) curve analysis was done and standardized mortality ratio was calculated. PIM2 Index assessment was performed by use of Hosmer and Lemeshow goodness-of-fit test.

Findings

240 patients were included in this study. The model fit was achieved adequately (P value=0.741). The area under the ROC curve was 0.795 (0.715-0.875 for 95% confidence interval) and standardized mortality ratio was 1.8 (1.28-2.465 for 95% confidence interval) High-risk group diagnosis with adjusted odds ratio (AOR)=14.75, pupil reaction to light (AOR=0.13) and duration of stay in PICU (AOR=1.03) had significant statistical association to pediatric mortality.

Conclusion

PIM2 is a good index for prediction of mortality in our pediatric intensive care unit. This study revealed that there is significant statistical association between the children mortality and the length of hspita;ization, pupillary light reflex and the risk level category on admission.  相似文献   
999.
1000.
High-dose methotrexate treatment requires pharmacological monitoring in order to tailor administration of folinic acid to reduce side effects. The aim of the study was to validate the adaptation of the EMIT reagent on the l'Unicel DxC 600? Beckman Coulter. The establishment of two assays was necessary to obtain a quantification limit as low as possible (0.05 μmol/L). The linearity of the adapted methods extends from 0.05 to 0.25 μmol/L on the one hand, and from 0.25 to 1 μmol/L on the other hand. For each method, fidelity and accuracy were studied and the limits of detection and quantification were quantified. The correlation with the FPIA method was performed on the Abbott TDX(?). The results of all tests are satisfactory with coefficients of variation (CV) of repeatability and reproducibility of less than 6%. However the daily assays are heavy as 66% of blood samples require at least two dosages and 30% a manual dilution.  相似文献   
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