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Plasma glutamate concentrations in human subjects are markedly lower when monosodium L-glutamate (MSG) is ingested in consomme with starch than when ingested in consomme alone. This study investigated whether sucrose had a similar effect. Six normal adult subjects (three male, three female) ingested two servings of beef consomme each providing 50 mg MSG/kg body weight in a randomized crossover design. One serving of consomme contained no added carbohydrate; the other provided 0.5 g sucrose/kg body weight. Ingestion of the consomme without sucrose significantly (p less than 0.05) increased the mean plasma glutamate concentration from baseline (4.44 +/- 0.97 mumol/dl) to a peak value of 18.1 +/- 6.99 mumol/dl 30 min after dosing. The area under the plasma glutamate concentration-time curve was 553 +/- 238 mumol/dl X min. When the consomme contained 0.5 g sucrose/kg body weight, both the mean peak plasma glutamate concentration (5.48 +/- 2.19 mumol/dl) and the area under the curve (105 +/- 46 mumol/dl X min) were significantly lower. These data confirm that metabolizable carbohydrate has a significant effect on plasma glutamate concentration response after MSG loading.  相似文献   
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Established nonexpanding hematomas can be successfully treated with minimal morbidity using standard liposucstion techniques at the bedside or in an outpatient setting under local anesthesia. The authors presents a series of eight patients and discuss current concepts of dealing with this common and distressing surgical complication.  相似文献   
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A technique to anesthetize turtles with ether is presented, in which a plastic cannula is passed through the glottis into the trachea. This procedure avoids apnea and allows ether vapours obtained from a chamber to be introduced, by the animal respiratory movements or by means of a pump, into the animal lungs. The anesthesia is rapidly obtained and lasts from 45-90 minutes. The time of recovery from anesthesia ranged from 60-90 minutes. With this technique no deaths were observed and the same animal could be anesthetized repeatedly.  相似文献   
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Parvalbumin 3 is an Abundant Ca2+ Buffer in Hair Cells   总被引:3,自引:0,他引:3  
Ca2+ signaling serves distinct purposes in different parts of a hair cell. The Ca2+ concentration in stereocilia regulates adaptation and, through rapid transduction-channel reclosure, underlies amplification of mechanical signals. In presynaptic active zones, Ca2+ mediates the exocytotic release of afferent neurotransmitter. At efferent synapses, Ca2+ activates the K+ channels that dominate the inhibitory postsynaptic potential. A copious supply of diffusible protein buffer isolates the three signals by restricting the spread of free Ca2+ and limiting the duration of its action. Using cDNA subtraction and a gene expression assay based on in situ hybridization, we detected abundant expression of mRNAs encoding the Ca2+ buffer parvalbumin 3 in bullfrog saccular and chicken cochlear hair cells. We cloned cDNAs encoding this protein from the corresponding inner-ear libraries and raised antisera against recombinant bullfrog parvalbumin 3. Immunohistochemical labeling indicated that parvalbumin 3 is a prominent Ca2+-binding protein in the compact, cylindrical hair cells of the bullfrog's sacculus, and occurs as well in the narrow, peanut-shaped hair cells of that organ. Using quantitative Western blot analysis, we ascertained that the concentration of parvalbumin 3 in saccular hair cells is approximately 3 mM. Parvalbumin 3 is therefore a significant mobile Ca2+ buffer, and perhaps the dominant buffer, in many types of hair cell. Moreover, parvalbumin 3 provides an early marker for developing hair cells in the frog, chicken, and zebrafish.  相似文献   
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The phospholipid-hydrolyzing enzyme phospholipase A2 (PLA2) (EC 3.1.1.4) exists in several forms which can be located in the cytosol or on cellular membranes. We review briefly cellular regulatory mechanisms involving covalent modification by protein kinase C and the action of Ca2+, cytokines, G proteins and other cellular proteins. The major focus is the role of phospholipid structure on PLA2 activity, including (1) the mechanism of PLA2 action on synthetic phospholipid bilayers, (2) perturbation of synthetic and cellular membranes with lipophilic agents and membrane-interactive peptides and (3) the ability of these agents to activate endogenous PLA2 activity, with emphasis on the venom and plant toxins melittin, cardiotoxin and Pyrularia thionein.  相似文献   
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