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61.
Bikas K. Arya Dennis Robert Sangeeta Das Bhattacharya Jayanta Mukhopadhyay 《Health Policy and Technology》2013,2(2):85-93
Drug resistance—arising from the misuse and overuse of antimicrobial agents—is becoming a major concern as new strains of resistant microorganisms are emerging and fewer new antimicrobial drugs are in development. This paper presents an idea of implementing a Real Time Web Based Information System to monitor changes in the antibiotic sensitivity of microorganisms, located at different areas and time periods based on data collected from accredited laboratories. This pattern can be mapped over geographical map of the area and can be interpreted by clinicians/policy makers. The authors demonstrate the use of such information system using cross sectional data obtained from a nasopharyngeal swab survey of 151 children affected with HIV. Such system can aid physicians to improve the choice of antibiotic to be administered using real time data. 相似文献
62.
Shilpee Das Jagruti L. Desai Hetal P. Thakkar 《Indian journal of pharmaceutical sciences》2013,75(6):707-715
The objective of the present work was to formulate gemcitabine hydrochloride loaded functionalised carbon nanotubes to achieve tumour targeted drug release and thereby reducing gemcitabine hydrochloride toxicity. Multiwalled carbon nanotubes were functionalised using 1,2-distearoylphosphatidyl ethanolamine-methyl polyethylene glycol conjugate 2000. Optimised ratio 1:2 of carbon nanotubes:1,2-distearoylphosphatidyl ethanolamine-methyl polyethylene glycol conjugate 2000 was taken for loading of gemcitabine hydrochloride. The formulation was evaluated for different parameters. The results showed that maximum drug loading efficiency achieved was 41.59% with an average particle size of 188.7 nm and zeta potential of −10−1 mV. Scanning electron microscopy and transmission electron microscopy images confirmed the tubular structure of the formulation. The carbon nanotubes were able to release gemcitabine hydrochloride faster in acidic pH than at neutral pH indicating its potential for tumour targeting. Gemcitabine hydrochloride release from carbon nanotubes was found to follow Korsmeyer-Peppas kinetic model with non-Fickian diffusion pattern. Cytotoxic activity of formulation on A549 cells was found to be higher in comparison to free gemcitabine hydrochloride. Stability studies indicated that lyophilised samples of the formulation were more stable for 3 months under refrigerated condition than at room temperature. Thus carbon nanotubes can be promising carrier for the anticancer drug gemcitabine hydrochloride. 相似文献
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R. Sinert S. Zehtabchi S. Desai P. Peacock B. T. Altura B. M. Altura 《Scandinavian journal of clinical and laboratory investigation》2013,73(3):317-326
Objective. Prior studies have been equivocal about whether or not serum levels of the divalent ions calcium and magnesium are altered during different types of seizures. Magnesium is a potential modulator of seizure activity because of its ability to antagonize the excitatory calcium influx through the N‐methyl‐D‐aspartate (NMDA) receptor. We hypothesize that serum ionized levels of calcium (Ca2+) and magnesium (Mg2+) would be altered significantly during certain types of seizures. Material and methods. A convenience sample of seizure patients presenting to an emergency department (ED) were enrolled in this prospective study. Novel ion‐selective electrodes were used to measure Ca2+ and Mg2+. Data were reported as mean values±standard deviations. Group comparisons were analyzed by ANOVA with post‐hoc testing using the Bonferroni, or the Fisher exact test, where appropriate, α = 0.05 (two‐tailed). Results. Forty‐nine patients with seizure and 32 healthy racially matched controls were included in the study. Seizure patients had a significantly (p<0.001) lower mean Mg2+, but not total serum Mg and a significantly (p<0.001) higher Ca2+/Mg2+ ratio than that in controls. Conclusions. We were able to show significantly lower Mg2+ and higher ionized Ca2+/Mg2+ ratios in seizure patients compared with a racially matched control group. 相似文献
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67.
Shaunak Desai Anil Sethi Christopher C. Ninh Stephen Bartol Rahul Vaidya 《European spine journal》2010,19(11):1953-1959
Cervical pedicle screws have been reported to be biomechanically superior to lateral mass screws. However, placement of these
implants is a technical challenge. The purpose of this investigation was to use an anatomic and a clinical study to evaluate
a technique for placement of the pedicle screws in the C7 vertebra using fluoroscopic imaging in only the anteroposterior
(A/P) plane. Ten adult cadaver C7 vertebrae were used to record the pedicle width, inclination and a suitable entry point
for placement of pedicle screws. A prospective study of 28 patients undergoing posterior instrumentation of the cervical spine
with C7 pedicle screw placement was also performed. A total of 55 C7 pedicle screws were placed using imaging only in the
A/P plane with screw trajectory values obtained by the anatomic study. Radiographs and CT scans were performed post-operatively.
The average posterior pedicle diameter of C7 vertebra was 9.5 ± 1.2 mm in this study. The average middle pedicle diameter
was 7.1 mm and the average anterior pedicle diameter was 9.2 mm. The average transverse pedicle angle was 26.8 on the right
and 27.3 on the left. CT scans were obtained on 20 of 28 patients which showed two asymptomatic cortical wall perforations.
One screw penetrated the lateral wall of the pedicle and another displayed an anterior vertebral penetration. There were no
medial wall perforations. The preliminary results suggest that this technique is safe and suitable for pedicle screw placement
in the C7 vertebra. 相似文献
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69.
Background: Placement of sciatic catheters with ultrasound and stimulating catheters is known. Literature regarding catheter placements with only ultrasound is limited. We aimed to investigate the feasibility of performing continuous sciatic nerve block exclusively with ultrasound guidance and minimal equipment. Method: Forty ASA 1 and 2 patients aged 8 months–10 years posted for congenital talipoequinovarus surgery were included in the study. Continuous sciatic catheters were placed under ultrasound guidance with 18‐ gauge Tuohy needle at the infragluteal fold. Then, 0.25% of bupivacaine 0.5 ml·kg?1 bolus was injected followed by continuous infusion later. Half the volume of the drug was injected prior to catheter insertion to improve visibility. The sciatic nerve, needle tip and shaft, catheter tip and the drug spread were visualized. The efficacy of the block intraoperatively and postoperatively was evaluated. Results: The sciatic nerve, needle shaft, and tip were well visualized in all 40 patients. The catheter tip was seen in 72.5% of patients. The effect of block was complete intraoperatively and postoperatively. Clinically significant complications were absent. Conclusion: We conclude that in children, continuous sciatic catheters can be accurately and efficaciously placed with minimal equipment with ultrasound alone. 相似文献
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