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101.
The use of laryngeal mask airway (LMA) as an alternative to the endotracheal tube (ETT) is becoming more popular in the practice of anesthesia. It is undeniable that this device has numerous advantages over endotracheal tube, however it does not provide an airtight seal between the airway and atmospheric gases. This may lead to pollution of the operating room environment with nitrous oxide. One hundreds adult patients undergoing general anaesthesia were divided into two groups. The airway in Group I was maintained with LMA with spontaneous ventilation and ETT with intermittent positive pressure ventilation (IPPV) was used for Group II. The result demonstrated that the ETT group recorded concentrations of nitrous oxide that were well above the NIOSH recommended eight hour time weighted average of 25ppm throughout the duration of surgery when compared to patients using LMA.  相似文献   
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We have previously shown that adhesion of human platelets to immobilized collagen is extremely rapid, with initial rates approaching 3% of single particles adhering per 10 ms. Here, we have investigated adhesion efficiency to collagen as a function of platelet density. Platelet subpopulations: low-density (1.040 < d < 1.065 g/ml), intermediate-density (1.065 < d < 1.070 g/ml) and high-density (1.070 < d < 1.080 g/ml) were separated by Percoll density gradient centrifugation. They constituted 24%, 47% and 29% of the total platelet population and had mean volumes of 6.01, 7.37 and 8.21 fl, respectively. Using a continuous-flow, micro-affinity column, we found that the most dense (large) platelets exhibited initial rate of adhesion 4 times greater than the least dense (small) platelets. They were also less sensitive to inhibition by prostacyclin (PGI2). In contrast, there was no significant difference in aggregation induced by high doses of ADP and collagen, indicating that the most dense platelets were not preferentially involved in aggregation induced by high doses of agonists. These results suggest that normal circulating platelets can be distinctly heterogeneous in their ability to adhere to collagen under arterial-flow conditions. The greater efficiency of high-density platelets may be related to increased content of the glycoprotein Ia/IIa (GPIa/IIa) complex.  相似文献   
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The spatio-temporal distribution and the controlling factors of petroleum hydrocarbons (PHCs) in sediments of Chilika lagoon was investigated. Samples were collected during three seasons and quantified using UV-fluorescence spectroscopy. Concentrations of PHCs in surface sediments varies from 0.18 to 12.13 ppm (mean 3.71?±?3.94 ppm). Compared to the lagoon, the monitoring stations adjacent to jetties with high boating activities tend to have higher PHC concentrations, suggesting that the contribution is likely to be from fossil fuel combustion and accidental seepage. The sediment organic matter (OM) of Chilika ranges from 0.26% to 6.23%. PHC maintains a positive correlation with OM (p?<?0.05; f?=?0.334), indicating the long term deposition of PHC as sediment OM. However, there is no significant relation between PHC and sediment texture, indicating its negligible control over PHC. The recorded PHC concentrations are below the threshold limit (70 ppm) as classified by United States (US) National Academy of Sciences (NAS) and also lower than those reported from similar ecosystems in India and overseas. Since the long term deposition and the bioaccumulation of PHC cannot be avoided, it is essential to monitor these parameters periodically.  相似文献   
106.
Acute Infantile Encephalopathy Predominantly Affecting the Frontal Lobes (AIEF) is a relatively recent described entity. This article includes case reports of two patients who had bifrontal involvement during acute febrile encephalopathy. Case 1 describes a 1-y-old boy who presented with hyperpyrexia and dialeptic seizures. Imaging revealed significant bilateral frontal lobe involvement while serology proved presence of Influenza B infection. Over a period of one?wk, he recovered with significant cognitive decline and perseveratory behavior. Another 6-y-old boy presented with language and behavioral problems suggestive of frontal dysfunction after recovering from prolonged impairment of consciousness following a convulsive status epilepticus. Bilateral superior frontal lesions with gyral swelling was evident on neuroimaging. These cases are among the very few cases of AIEF described in recent literature and the article also reviews this unique subtype of acute encephalopathy.  相似文献   
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OBJECTIVE: To survey French trainees in Obstetrics and Gynaecology and evaluate their theoretical training and practice of vaginal breech delivery (VBD). STUDY DESIGN: We conducted a national survey between January and April 2004 among the 817 French trainees undergoing a 5-year training program in obstetrics and gynaecology. Trainees in years 1-3 were considered as juniors, and those in years 4 and 5 as seniors. Respondents were invited to specify whether they had received theoretical teaching in the management of VBD, and to indicate the number of VBDs they had performed during their training. RESULTS: The questionnaire was returned by 156 (19%) trainees and of these 140 questionnaires were suitable for analysis. Overall, 35% of the respondents had never been taught the management of a VBD. Among the senior trainees, 33% had performed less than four VBDs, and 23% had not received any teaching on how to manage a VBD. CONCLUSION: The level of theoretical training and practice in the management of VBD seems to have diminished and does not bring the French trainees in obstetrics and gynaecology to the required standard of competence.  相似文献   
110.
Little is known about insulin's wound healing capability in normal as well as diabetic conditions. We here report specific interaction of silver nanoparticles (AgNPs) with insulin by making a ~2?nm thick coat around the AgNPs and its potent wound healing efficacy. Characterization of the interaction of human insulin with silver nanoparticles showed confirmed alteration of amide-I in insulin whereas amide-II and III remained unaltered. Further, nanoparticles protein interaction kinetics showed spontaneous interaction at physiological temperature with ΔG, ΔS, Ea and Ka values ?7.48, 0.076, 3.84 kcal mol?1 and 6?×?105?s?1 respectively. Insulin loaded AgNPs (IAgNPs) showed significant improvement in healing activity in vitro (HEKa cells) and in vivo (Wister Rats) in comparison with the control in both normal and diabetic conditions. The underlying mechanism was attributed to a regulation of the balance between pro (IL-6, TNFα) and anti-inflammatory cytokines (IL-10) at the wound site to promote faster wound remodeling.  相似文献   
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