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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   
95.
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   
96.
Echocardiography     
Echocardiography occupies a unique place as an investigative tool in cardiology. This introduction to the technique reviews the basic principles and outlines the diagnosis of common cardiac lesions. Being entirely noninvasive, echocardiography can be repeated to ascertain the severity and observe the progression of cardiac lesions.  相似文献   
97.
A flat blood sugar response to the oral glucose tolerance test has long been accepted as an implication of impaired intestinal absorption of carbohydrate. However, this study indicates that the flat response is a normal variant and depends on how the test is performed and when the blood is sampled. It also is conjectured that the carbohydrate challenge may trigger a burst of insulin that modifies the blood sugar response.  相似文献   
98.
Sepsis due to unabated inflammation is common. Increased production of pro-inflammatory cytokines, free radicals, and eicosanoids has been detected in sepsis and other critical illnesses but could also be due to decreased synthesis and release of anti-inflammatory molecules. Increased serum adipose-fatty acid-binding protein (A-FABP) levels can cause insulin resistance and have been reported in the critically ill, serve as a marker of prognosis, and thus link metabolic homeostasis and inflammation. A-FABP can be linked to the expression of Toll-like receptors, macrophage activation, synthesis and release of pro-inflammatory cytokines interleukin-6 and tumor necrosis factor-alpha, activation of cyclooxygenase 2 (COX-2) expression, and eicosanoid synthesis, events that can cause insulin resistance and initiation and progression of inflammation and sepsis. Unsaturated fatty acids and their anti-inflammatory products, such as lipoxins, resolvins, and protectins, may suppress A-FABP expression, inhibit macrophage and COX-2 activation, and decrease production of pro-inflammatory cytokines and ultimately could lead to a decrease in insulin resistance and resolution of inflammation and recovery from sepsis. Serial measurement of these pro- and anti-inflammatory molecules and correlation of their levels to the progression to or recovery from (or both) sepsis and other inflammatory processes may form a new approach to predict prognosis in inflammatory conditions and eventually could lead to the development of new therapeutic strategies.  相似文献   
99.
The dorsolateral pontine nucleus (DLPN) is a major component of the cortico-ponto-cerebellar pathway that carries signals essential for smooth pursuit. This pathway also carries visual signals that could play a role in visually guided motor learning in the vestibular ocular reflex (VOR). However, there have been no previous studies that tested this possibility directly. The aim of this study was to determine the potential role of the DLPN in short-term VOR gain adaptation produced by viewing a scene through lenses placed in front of both eyes. In control experiments, adaptation of VOR gain was achieved by sinusoidal rotation (0.2 Hz, 30 degrees /s) for 2 h while the monkey viewed a stationary visual surround through either magnifying (x2) or minifying (x0.5) lenses. This led to increases (23-32%) or decreases (22-48%) of VOR gain as measured in complete darkness (VORd). We used injections of muscimol, a potent GABA(A) agonist (0.5 microl; 2%), to reversibly inactivate the DLPN, unilaterally, in three monkeys. After DLPN inactivation, initial acceleration of ipsilateral smooth-pursuit was reduced by 35-68%, and steady-state gain was reduced by 32-61%. Despite these significant deficits (P < 0.01) in ipsilesional smooth pursuit, the VOR during lens viewing was similar to that measured in preinjection control experiments. Similarly, after 2 h of adaptation, VORd gain was not significantly different (P > 0.61) from control adaptation values for either ipsi- or contralesional directions of head rotation. This was the case even though a stable ipsilesional smooth pursuit deficit persisted throughout the full adaptation period. Our results suggest that visual error signals for short-term adaptation of the VOR are derived from sources other than the DLPN perhaps including other basilar pontine nuclei and the accessory optic system.  相似文献   
100.
Reports on metastatic differentiated carcinoma in endemic goiter regions are scarce. The aim of this study was to look into the clinicopathological profile and outcome of patients with metastatic differentiated thyroid carcinoma (DTC) of endemic origin. This was a retrospective study of 28 cases of metastatic DTC out of a total of 140 DTC patients managed between 1990 and June 1999. Demographic data, clinicopathological profile, operative and radioiodine ablation therapy details, and follow-up findings were noted. The overall incidence of distant metastases in our series was 20%. Mean age was 48.5 +/- 12.8 years (32.1%patients were < 45 years). Most metastases were detected synchronously (85.7%) and were multiple, with the skeletal system being the commonly affected site. Out of 22 cases having skeletal metastases, 6 patients were young (< 45 years). Though most patients with skeletal metastases had follicular carcinoma (FTC), 4 cases had papillary thyroid cancer (PTC). Near total or total thyroidectomy was done in 26 cases. Sixteen patients required regional lymph node dissection. Resection of metastases was performed in 9 cases.Histopathological diagnosis was PTC, FTC, and poorly differentiated carcinoma in 32.1%, 50.0%, and 17.9% of cases, respectively. Most patients had good symptomatic palliation following administration of I131 therapy. In 17.9% of cases there were locoregional recurrences. There was an overall 28.6% mortality. Two patients expired in the perioperative period. Six others died in follow-up (all within 3-9 months). In contrast to iodine sufficient regions, the incidence of metastases was high; the majority of cases had synchronous, symptomatic skeletal metastases. Skeletal metastases were not infrequent even in cases of PTC and in young patients. One-third of the cases were young. Though survival was poor despite aggressive management, significant symptomatic palliation could be achieved in most cases.  相似文献   
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