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51.
The Laryngeal Mask Airway (LMA) is a frequently used efficient airway device, yet it sometimes seals poorly, thus reducing the efficacy of positive-pressure ventilation. The Perilaryngeal Airway (CobraPLA) is a novel airway device with a larger pharyngeal cuff (when inflated). We tested the hypothesis that the CobraPLA was superior to the LMA with regard to insertion time and airway sealing pressure and comparable to the LMA in airway adequacy and recovery characteristics. After midazolam and fentanyl administration, 81 ASA physical status I-II outpatients having elective surgery were randomized to receive an LMA or CobraPLA. Anesthesia was induced with propofol (2.5 mg/kg IV), and the airway was inserted. We measured 1) insertion time; 2) adequacy of the airway (no leak at 15-cm-H2O peak pressure or tidal volume of 5 mL/kg); 3) airway sealing pressure; 4) number of repositioning attempts; and 5) sealing quality (no leak at tidal volume of 8 mL/kg). At the end of surgery, gastric insufflation, postoperative sore throat, dysphonia, and dysphagia were evaluated. Data were compared with unpaired Student's t-tests, chi2 tests, or Fisher's exact tests; P < 0.05 was significant. Patient characteristics, insertion times, airway adequacy, number of repositioning attempts, and recovery were similar in each group. Airway sealing pressure was significantly greater with CobraPLA (23 +/- 6 cm H2O) than LMA (18 +/- 5 cm H2O, P < 0.001). The CobraPLA has insertion characteristics similar to the LMA but better airway sealing capabilities.  相似文献   
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We report an unusual severe systemic reaction that occurred in a woman after a (99m)Tc-methylene diphosphonate bone scan and for which no alternative explanation could be found. The bone scintigram showed diffusely increased uptake in the liver and kidneys accompanied by reversible dysfunction of these organs and dermatologic manifestations. We speculate that an immune-mediated mechanism may have caused this unusual reaction.  相似文献   
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Introduction: Anatomical studies have been conducted in different ethnic groups to measure the bony vertebral dimensions and to determine the normal limits which will serve as guidelines in assessing lumbar stenosis. Aim: To determine the normal range of measurements of lumbar vertebrae in Western Maharashtra population. Materials and methods: Various dimensions of lumbar vertebrae from L1 to L5 were measured in 420 lumbar vertebrae, collected from the Department of Anatomy, Government Medical College, Miraj, and other Medical colleges of Western Maharashtra. Results and discussion: Mean transverse diameter of vertebral body as well as of spinal canal and anteroposterior diameter of vertebral body were minimum at L1 and maximum at L5. The mean anteroposterior diameter of spinal canal showed a gradual decrease from L1 to L5 in both sexes. Making use of the above parameters, the canal body ratio and spinal index of Jones were calculated. These parameters were also compared with those of previous studies. Similarly, from the above parameters, the values suggestive of lumbar canal stenosis and intraspinal tumor were calculated. Conclusion: The present study shows regional and ethnic variation in the parameters of lumbar vertebrae, thus emphasizing the need to determine the normal range of values for different populations.  相似文献   
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Cryptococcus neoformans has a worldwide distribution. Meningoencephalitis is the most common manifestation of cryptococcosis. The outcome of a patient with cryptococcal infection depends on the immune status of the host. Patients with nephrotic syndrome are particularly susceptible to cryptococcal infection not only due to innate changes in their immune system but also because of the immunosuppressive agents used in the treatment. We report an 8-year-old boy with nephrotic syndrome, who developed cryptococcal meningitis and died of fulminant intracranial hypertension.  相似文献   
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The main objective of this study was to develop and characterize a pH-sensitive biodegradable polymeric nanoparticulate system for tumor-selective paclitaxel delivery. A representative hydrophobic poly(beta-amino ester) (poly-1) was synthesized by conjugate addition of 4,4'-trimethyldipiperidine with 1,4-butanediol diacrylate. Poly-1 (M(n) 10,000 daltons) nanoparticles were prepared by the controlled solvent displacement method in an ethanol-water system in the presence of Pluronic) F-108, a poly(ethylene oxide) (PEO)-containing non-ionic surfactant. Control and PEO-modified nanoparticles were characterized by Coulter counter, scanning electron microscopy (SEM), zeta potential measurements, and electron spectroscopy for chemical analysis (ESCA). Polymer degradation studies were performed in phosphate-buffered saline (PBS, pH 7.4) at 37 degrees C. Paclitaxel loading capacities and efficiencies were determined and release studies were performed in Tween)-80 (0.1%, w/v)-containing PBS at 37 degrees C. Control and PEO-modified nanoparticles, labeled with rhodamine-123, were incubated with BT-20 cells to examine the uptake and cellular distribution as a function of time. PEO-modified nanoparticles with an average size of 100-150 nm and a positive surface charge of 37.0 mV were prepared. SEM analysis showed distinct smooth, spherical particles. The ether (-C-O-) peak of the C(1s) envelope in ESCA confirmed the surface presence of PEO chains. Polymer biodegradation studies showed that almost 85% of the starting material degraded after 6 days. The maximum paclitaxel loading efficiency attained was 97% at 1.0% (w/w) of the drug. Paclitaxel release studies showed that approximately 10% was released in the first 24 h, 80% after 3 days, and the entire content was released in approximately 5 days. After 1 h of incubation, a large fraction of the administered control and PEO-modified poly-1 nanoparticles was internalized in BT-20 cells. Results of this study demonstrate that PEO-modified poly-1 nanoparticles could provide increased therapeutic benefit by delivering the encapsulated drug to solid tumors.  相似文献   
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Smile is one of the most natural and important expressions of human emotion. Man uses his lips mainly to register his emotions. Thus, the slightest asymmetry or weakness around the lips and mouth may transform this pleasant expression into embarrassment and distortion. The circumoral musculature, the major part of which is supplied by the marginal mandibular branch of the facial nerve, is the main factor in this expression. Therefore, an injury to this nerve during a surgical procedure can distort the expression of the smile as well as other facial expressions. This nerve often gets injured by surgeons in operative procedures in the submandibular region, like excision of the submandibular gland due to lack of accurate knowledge of variations in the course, branches and relations. In the present study, 50 facial halves were dissected to study the origin, entire course, termination, branches, muscles supplied by it, its anastomoses with other branches of facial nerve on the same as well as on the opposite side and its relations with the surrounding structures. The marginal mandibular branch of the facial nerve was found superficial to the facial artery and (anterior) facial vein in all the cases (100%). Thus the facial artery can be used as an important landmark in locating the marginal mandibular nerve during surgical procedures. Such a study can help in planning precise and accurate incisions and in preventing the unrecognized severance of this nerve during surgical procedures.  相似文献   
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Polymers are the high molecular weight compounds of natural or synthetic origin, widely used in drug delivery of formulations. These polymers are further classified as hydrophilic or hydrophobic in nature. Depending upon this characteristic, polymers exhibit different release behavior in different media. This property plays an important role in the selection of polymers for controlled, sustained or immediate release formulations. The review highlights the literatures related to the research made on several polymers regarding the release kinetics which made them a novel approach for modifying the action of the particular formulation.  相似文献   
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