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101.
The feasibility and accuracy of using a mock treatment to screen suitable patients for respiratory-gated image-guided radiotherapy was investigated. Radio-opaque fiducials implanted adjacent to the liver tumor were used for online positioning to minimize the systematic error in patient positioning. The consistency in the degree of correlation between the external and internal fiducials was analyzed during a mock treatment. This technique could screen patients for gated therapy, reduce setup inaccuracy, and possibly individualize treatment margins.  相似文献   
102.
Unique properties of thermodynamic activity of solvents in topical semisolids and its effects on in vitro product performance have not been fully understood. Mechanistic investigation was undertaken to demonstrate the significance of thermodynamic potential of solvents [water activity (aw) or solvent activity (as)] on in vitro performance of model topical formulations. Drug transport across synthetic membranes was found to decrease with decreasing water activity of formulations. Similarly, in vitro permeation of model permeant (caffeine) across porcine epidermis was found to decrease with decreasing water activity of formulations. Notably, relatively low water activity formulations (aw, 0.78) induced dehydration in porcine skin associated with significant structural changes like detachment of individual stratum corneum layers. Inclusion of hydrating agents (propylene glycol) in low water activity (aw, 0.78) formulations restored hydration levels and structural integrity of porcine skin. Most importantly, incremental inclusion of propylene glycol in low water activity formulations (aw, 0.78) enhanced in vitro permeation of model permeant (fluorescein sodium). Further investigation revealed that variability in processing conditions (high shear mixing during emulsification step) could modulate water activity in semisolid formulations despite their compositional sameness. In retrospect, water activity was found to be a critical quality attribute of topical semisolid products which impacts overall product performance and drug delivery.  相似文献   
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104.
Human beings and ecosystems are being possibly exposed to CNTs, as there is a rise in global production rate of carbon nanotubes (CNTs). This may affect the health of humans and increases the environmental risk. We have already reported the pulmonary toxicity due to the inhalation of MWCNTs. We claim that a compound with anti-inflammatory and antioxidant activity may ameliorate the CNT-induced toxic effect. With this view, we have investigated the ameliorative effect of intravenously-administered nano bis-demethoxy curcumin analog (NBDMCA) against MWCNTs-induced inhalation toxicity by examining the lung histopathology for inflammatory cell dynamics, pulmonary remodeling and estimating the inflammatory biomarkers in the broncho-alveolar lavage fluid. We observed that NBDMCA could ameliorate the injury as evidenced by the decline in the levels of markers of inflammation, cell damage, and the histopathological changes induced by MWCNTs. We conclude that NBDMCA may be used to reduce the risk of MWCNTs-induced inhalation toxicity.  相似文献   
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106.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Occurrence of faecal indicator bacteria (FIB) is being reported regularly by various researchers. But there...  相似文献   
107.
The amino acid intermediate homocysteine (Hcy) is formed during the metabolism of methionine to cysteine. Hyperhomocysteinemia (HHcy) is recognized as an independent risk factor for coronary atherosclerosis. The circulating levels of total Hcy (tHcy) can increase due to intake of foods rich in methionine or deficiencies of vitamins such as folate, pyridoxine and cyanocobalamin, which are required for the metabolism of Hcy. In addition, mutations in the genes coding for Hcy metabolizing enzymes can contribute to an increase in tHcy levels. Clinical and epidemiological studies have shown that an elevated level of tHcy measured in serum or plasma is a strong predictor of cardiovascular disease risk, which appears to be greatest in patients who have HHcy following a methionine load. Intimal hyperplasia (IH) (intima/media [I/M] ratio) is the universal response of a vessel to injury and may result in vasoconstriction when left unattended. The effect of dietary HHcy on balloon catheter-injured carotid artery and its modulation (if any) by the peroxisome proliferator-activated receptor agonist gamma rosiglitazone was evaluated in 12-week-old female Sprague-Dawley rats fed either a control diet or a diet containing 1% L-methionine. Once the rats were established on the diet, the group that was fed 1% L-methionine was further subdivided and either given an aqueous preparation of 3 mg/kg/day rosiglitazone or the vehicle via oral gavage for one week. This was followed by surgically injuring the left carotid artery using a Maverick Over-The-Wire catheter (2.0 mm × 20 mm, 3.2F; Boston Scientific, USA). The rats were continued on their respective diets and drug regimen for 21 days postsurgery. On day 22 of the procedure, the rats were sacrificed for collection of blood, the carotid arteries and liver for biochemical and histological evaluation. Compared with controls there was a significant increase in both tHcy levels and I/M ratio in the rats fed 1% L-methionine (5.4±0.28 μM versus 32.8±3.01 μM, P<0.002; and 0.175±0.05 versus 1.05±0.23, P<0.005, respectively). The effect of rosiglitazone in rats fed the control diet was not prominent. On the other hand, administration of rosiglitazone to the rats on the 1% L-methionine diet significantly reduced the levels of serum tHcy (16.6±2.1 μM versus 32.8±3.01 μM, P<0.001); however, the tHcy levels remained significantly elevated compared with animals on the control diet (P<0.002). The group receiving the L-methionine diet plus rosiglitazone had an inhibition in the development of IH compared with those receiving the L-methionine diet alone (I/M of 0.278±0.041 versus 1.05±0.23, P<0.01). Moreover, the development of IH in the group receiving the L-methionine diet plus rosiglitazone treatment was not significantly different from that observed in the group on the control diet without rosiglitazone (0.278±0.041 versus 0.175±0.05, respectively). These findings may have important implications in deciphering the molecular mechanisms involved in the augmentation of IH in HHcy and modulation of this process by rosiglitazone.  相似文献   
108.
Myasthenic gravis (MG) is an autoimmune disease associated with acetylcholine receptor deficiency. Patients with MG exhibit increased sensitivity to non-depolarising muscle relaxants. In an attempt to avoid neuromuscular blockers, we used sevoflurane in two myasthenic patients undergoing trans-sternal thymectomy. Inhalation of 8% sevoflurane in oxygen using vital capacity technique produced rapid, pleasant and smooth induction and provided good tracheal intubating conditions. In both patients anaesthesia was maintained with 1.5-2% end-tidal concentration of sevoflurane and nitrous oxide in oxygen without adjunctive neuromuscular blocking agents. There were minimal changes in cardiovascular variables and recovery was faster. It is suggested that sevoflurane may be the main anaesthetic for both induction and maintenance in myasthenic patients undergoing trans-sternal thymectomy.  相似文献   
109.
This random multistage cross sectional population survey was undertaken to determine the prevalence of diabetes mellitus (DM) and impaired fasting glycemia/glucose (IFG) in subjects aged 25 years and above in India. The study was carried out in 108 centers (49 urban and 59 rural) to reflect the size and heterogeneity of the Indian population. 41,270 (20,534 males and 20,736 females) subjects were studied. 21,516 (10,865 males and 10,651 females) were from urban areas and 19,754 (9669 males and 10,085 females) from rural areas. Blood samples were taken after a fast of 10-12h and the subjects were categorized as having IFG or DM using the 1997 American Diabetes Association criteria. The age and gender standardized prevalence rate for DM and IFG in the total Indian population was 3.3 and 3.6% respectively (P < 0.001). The standardized prevalence of DM and IFG in urban areas was significantly higher than that for the rural population (urban DM prevalence 4.6% versus rural DM prevalence 1.9%, P < 0.001; urban IFG prevalence 4.8% versus rural IFG prevalence 2.5%, P < 0.001). There was no statistically significant difference in the prevalence between DM (4.6%) and IFG (4.8%) in the urban population. The rural prevalence of IFG (2.5%) was significantly (P <0.001) more than the rural prevalence of DM (1.9%). Type 2 diabetes is a major health problem is India.  相似文献   
110.
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