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1.
1. The antiinflammatory actions of glucocorticoid steroids are thought to occur through induction of the protein lipocortin-1 (LC-1; annexin-1). The purpose of the current study was to investigate whether astrocytic LC-1 content was increased in the presence of a synthetic glucocorticoid, dexamethasone. 2. Steroid-induced changes in cellular levels of LC-1 in astrocytes were determined by electrotransfer and immunoblotting techniques. Separate cell fractions were investigated to study the influence of dexamethasone on astroglial LC-1 content. The effect of culture state on LC-1 expression was also examined. 3. Intracellular LC-1 content was found to decrease after initiation of culture, with a substantial rise in both cell proliferation and LC-1 expression occurring after the replenishment of medium containing steroid-free serum. A further increase in intracellular LC-1 occurred upon incubation with dexamethasone. The glucocorticoid-induced change in intracellular LC-1 was a time-dependent event and coincided with an increase in membrane-associated LC-1. 4. The findings in this study indicate that astrocytic LC-1 content is influenced by cell culture conditions and, in the presence of glucocorticoid steroids, the cellular localization of LC-1 is altered. This may indicate that LC-1 has functions at more than one cellular locality.  相似文献   
2.
We discovered that a food aversion could be conditioned in anesthetized sheep. Sheep were allowed to eat a familiar food (alfalfa-grain pellets) for 30 min, and 90 min later they were given either an intraruminal (IR) injection of water (C), an IR injection of LiCl (L), anesthesia followed by an IR injection of water (A), or anesthesia followed by an IR injection of LiCl (A+L). Induction of anesthesia was by an intravenous injection of pentobarbitone sodium, and maintenance of deep anesthesia was by halothane. Sheep were maintained in deep anesthesia for 2 h to ensure that the effects of LiCl on the acquisition of a food aversion, which occur within about 1 h, were completed before they awakened. When tested 5 days later, sheep that received LiCl (treatments L and A+L) consumed less alfalfa-grain pellets than sheep that did not receive LiCl (treatments C and A) (241 g vs. 306 g; p = 0.057). Intake of sheep that were anesthetized (treatments A and A+L) did not differ from that of sheep that were not anesthetized (treatments C and L) (295 g vs. 252 g; p = 0.183). Nor was there an interaction between LiCl and anesthesia (p = 0.423). Thus, we conclude that changes in preferences for foods caused by postingestive feedback occur automatically every time food is ingested (i.e., they are noncognitive), and the kind and amount of feedback is a function of the match between the food's chemical characteristics and its ability to meet the animal's current demands for nutrients.  相似文献   
3.
We have treated 50 patients with stage III, VI malignant tumors confirmed by pathology. The patients were divided into two groups. One group was treated by combination of chemotherapy and traditional Chinese medicine (treatment group); the other only by chemotherapy (control group). The effect of cancer treatment was evaluated according to the criteria of WHO. The results showed that the effective rate was 80% in treatment group and 52% in control group. The pain relieving rate was 68% in treatment group and 40% in control group (P < 0.01). This fact demonstrates that the application of traditional Chinese medicine can invigorate blood circulation, eliminate blood stasis, soften hardness and dissolve the mass, nourish blood and increase vigor. This kind of application can not only enhance the effect of cancer treatment but also increase the cancer pain relieving rate.  相似文献   
4.
The authors presented the cases of two children with inflammatory myofibroblastic (IMF) tumor and reviewed the literature to facilitate the preoperative recognition, delineate the clinical features, and describe the natural history of this entity. The first child had IMF tumor arising from the mesentery of the small intestine. He presented with an abdominal mass associated with severe inflammatory response manifested by fever, impaired growth, thrombocytosis, and microcytic, hypochromic anemia. After surgical resection, his fever resolved and his growth rate and the laboratory abnormalities normalized. Five months after initial diagnosis, the fever, anemia, and thrombocytosis recurred along with two tumors arising from the omentum and the abdominal soft tissue. After the second surgery, he remains free of recurrent disease for 30 months. The second child presented with a lung mass that was radiologically indistinguishable from pulmonary sequestration. After surgical resection, she remains free of recurrent disease for 18 months. IMF tumor should be considered in any solid tumor that occurs in association with a chronic inflammatory response. IMF tumor should also be considered in the differential diagnosis of pulmonary sequestration.  相似文献   
5.
D-Amino acid replacements and the determination of resulting structural changes are a useful tool to recognize amphipathic helices in biologically active peptides such as neuropeptide Y and corticotropin-releasing factor. In this paper the secondary structures of one amphipathic alpha-helical peptide and its double D-amino acid analog have been determined by means of 1H NMR and CD spectroscopies under equivalent conditions. The chemical shifts (NH and C alpha H) and the analysis of nuclear Overhauser effects show a split of the continuous helix for the all-L peptide into two helices at the position of double D-amino acid replacement. Hydrogen exchange rates correlate with water accessibilities in the hydrophobic/hydrophilic face and confirm the amphipathic helical structure in the all-L peptide as well as in its double D-amino acid analog. A significantly accelerated hydrogen isotope exchange rate is observed for the D-Ala9 backbone proton, implying an increased flexibility at that position. These results show that the incorporation of an adjacent pair of D-amino acids only causes a local change in structure and flexibility, which makes the double D replacement interesting as a tool for specific helix-disturbing modifications to search for helical conformations in biologically active peptides.  相似文献   
6.
Reviews the research concerning the possible functional roles of the prosodic aspects of infant-directed speech ("baby-talk"), and shows that this style of speaking could have both attentional and affective functions (in addition to linguistic ones). Studies of other speech registers could profit from taking similar approaches and even using similar techniques to those used in infant-directed speech research to tease apart the linguistic, attentional, and affective components of these other speaking styles. Nursing-home register is used to exemplify the importance of examining the social, emotional, and linguistic ramifications of a communication style separately. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
A 6-year-old white female was found to have an adenoid cystic carcinoma originating in a lacrimal gland. Eighteen months following diagnosis, the tumor recurred. Conservative surgery has been the sole mode of therapy. To date, after four operations and quadrimenstral imaging surveillance, there is no sign of disease progression. Our purpose is to record the unusual occurrence of an adenoid cystic carcinoma of the lacrimal gland in a child. An interim report, 32 months after diagnosis, is presented.  相似文献   
8.
Alfalfa juice was extracted from plants during the graving phases of the first and second crops. The alfalfa juice was dried and solute concentrations were measured periodically during the process using freezing point depression (FPD) as an indicator. Solute/solvent weight ratios were calculated from the freezing point depression of fresh unconcentrated 'uice extracted from both firsc and second crops. At the time of harvest, tie FPD was a function of this ratio. The first and second crops behaved distinctively different during the drying process, with the second having a larger soluce concentration and a greater FPD at a given moisture content. The appearance of preci itate during the drying process and the general1 large FPD makes this materiay a questionable product for drying vitg low temperature processes.  相似文献   
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