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It has been suggested that placebo analgesia involves both higher order cognitive networks and endogenous opioid systems. The rostral anterior cingulate cortex (rACC) and the brainstem are implicated in opioid analgesia, suggesting a similar role for these structures in placebo analgesia. Using positron emission tomography, we confirmed that both opioid and placebo analgesia are associated with increased activity in the rACC. We also observed a covariation between the activity in the rACC and the brainstem during both opioid and placebo analgesia, but not during the pain-only condition. These findings indicate a related neural mechanism in placebo and opioid analgesia. 相似文献
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The live attenuated temperature-sensitive (ts+) Mycoplasma synovia (MS) strain, MS-H, is used as a vaccine in a number of countries to control virulent MS infection in commercial chicken flocks. Nine out of 50 isolates made from flocks vaccinated with MS-H were found to have lost the ts+ phenotype of the original vaccine strain. In order to examine the influence of the ts- phenotype on virulence of the isolates, four of the ts- isolates, the MS-H vaccine, and the vaccine parent strain 86079/7NS were administered by aerosol in conjunction with infectious bronchitis virus to 3-wk-old specific-pathogen-free chickens. The four ts- clones induced only minimal air sac lesions that were not different in severity from those caused by MS-H vaccine; however, the vaccine parent strain 86079/7NS caused air sac lesions that were significantly greater than those of MS-H and all ts- clones. The vaccine parent strain 86079/7NS and two of the ts- clones were recovered from the air sacs of the respectively infected chickens whereas the MS-H vaccine and two other ts- clones were not. Three of the ts- isolates caused increased tracheal mucosal thicknesses that were significantly greater than those from birds inoculated with MS-H, and one caused increased tracheal mucosal thicknesses that were significantly less than those from birds inoculated with 86079/7NS. In conclusion, unlike the MS-H vaccine, the MS-H ts- clones were associated with minor changes in tracheal mucosa; however, unlike the vaccine parent strain, they did not induce lesions in the air sacs. These results suggest that factors other than ts+ phenotype are involved in the attenuation of the MS-H vaccine. 相似文献
996.
Metolachlor is one of the most widely used herbicides in the world for controlling weeds. It has been detected in both ground and surface waters in the United States, and there are rising concerns in regard to its health risks and in developing effective treatment processes for its removal from water. Degradation of metolachlor via ultraviolet (UV) photolysis and an UV/hydrogen peroxide advanced oxidation process (AOP) was studied. The quantum yield of metolachlor at 254 nm was found to be 0.302 +/- 0.001 mol E-1 through direct UV photolysis in the range of pH 6-8. The second-order rate constant of the reaction between metolachlor and hydroxyl radical was determined to be 9.07 (+/-0.21) x 10(9) M-1 s-1 by using a competition kinetics model that utilized nitrobenzene as a reference compound. In addition, these parameters were successfully applied in modeling the kinetics of elimination of metolachlor using an UV/H2O2 process in both laboratory and natural waters. The formation of several photolysis byproducts was identified using gas chromatography/mass spectrometry, and a scheme for the metolachlor photodegradation pathway is proposed. 相似文献
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Biswas A Sharma BK Vermillion K Willett JL Cheng HN 《Journal of agricultural and food chemistry》2011,59(7):3066-3070
This paper describes the preparation of a new type of branched vegetable oil and its methyl ester that involves the formation of acetonides. A facile and environmentally friendly synthesis has been found to produce acetonides that entails the use of ferric chloride as a catalyst and is conducted at room temperature. The products have been fully characterized with the help of model compounds, including elemental analysis, infrared (IR) spectroscopy, nuclear magnetic resonance (NMR), and gas chromatography-mass spectrometry (GC-MS). 相似文献
999.
Lisa Smart BVSc Karl E. Jandrey DVM DACVECC 《Journal of Veterinary Emergency and Critical Care》2008,18(4):393-398
Objective: To describe the case management for a dog diagnosed with a nasopharyngeal polyp.
Case summary: A 9-week-old Shar-Pei puppy presented for progressive dyspnea and collapse. Clinical signs were consistent with an upper airway obstruction (UAO) and a temporary tracheostomy was performed. The puppy was at first diagnosed with and treated for brachycephalic airway syndrome but continued to exhibit signs of an UAO after soft palate resection. Nasopharyngoscopy revealed a nasopharyngeal polyp causing the UAO, which was surgically removed. The puppy has been free of clinical signs for 1 year after removal of the polyp.
New or unique information provided: This is the first report of a nasopharyngeal polyp causing a life-threatening UAO in a puppy. It emphasizes the importance of examining the nasopharyngeal space in neonates presenting with UAO. 相似文献
Case summary: A 9-week-old Shar-Pei puppy presented for progressive dyspnea and collapse. Clinical signs were consistent with an upper airway obstruction (UAO) and a temporary tracheostomy was performed. The puppy was at first diagnosed with and treated for brachycephalic airway syndrome but continued to exhibit signs of an UAO after soft palate resection. Nasopharyngoscopy revealed a nasopharyngeal polyp causing the UAO, which was surgically removed. The puppy has been free of clinical signs for 1 year after removal of the polyp.
New or unique information provided: This is the first report of a nasopharyngeal polyp causing a life-threatening UAO in a puppy. It emphasizes the importance of examining the nasopharyngeal space in neonates presenting with UAO. 相似文献
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