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Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate whether the preparation of Descemet membrane endothelial keratoplasty (DMEK) grafts into various shapes affect their...  相似文献   
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Responses of the isolated vas deferens of guinea pig to clonidine (inhibition of contractions to field stimulation at 2.5 Hz), tyramine (inhibition of contractions to field stimulation at 10 Hz), prostaglandin E2 (inhibition of contractions to field stimulation at 10 Hz), and noradrenaline (contraction of longitudinal muscle) were determined after administration of decamethrin (18 mg kg-1, ip) once a day for 3 consecutive days. Treatment with decamethrin produced a subsensitivity of the prejunctional alpha 2-adrenoceptor system as evidenced by the fact that the alpha 2-agonist clonidine was less effective in decreasing nerve-stimulated induced contractions of the vas deferens. In addition, the presynaptic action of tyramine on postganglionic motor transmission was impaired. However, no detectable changes in the inhibition by prostaglandin E2 of twitch responses were produced by decamethrin. Decamethrin treatment had a significant effect on noradrenaline responsiveness, causing an increase in the maximum contractile response, indicative of an enhanced postreceptor mechanism. The present results suggest that decamethrin treatment reduces peripheral presynaptic adrenoceptor sensitivity. This reduction will lead subsequently to increased noradrenaline release and postsynaptic adrenoceptor upregulation.  相似文献   
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To explore the radioprotective effect of a standardized North American ginseng extract (NAGE) on human peripheral blood lymphocytes (PBL), a micronuclei (MN) assay was conducted in PBL obtained from 12 volunteers. NAGE (50-1000 microg/mL) and WR-1065 (1 mM and 3 mM) were applied to PBL cultures at 0 h and 90 min post-irradiation. It was found that (1) the baseline MN yield of PBL ranged from 14.4 +/- 1.5 to 15.9 +/- 1.5 per 1000 binucleated cells (p > 0.05); after irradiation (1 Gy and 2 Gy), the MN yield increased sharply; (2) MN yields declined with increasing concentrations of NAGE and WR-1065. Even at 90 min post-irradiation of 1 Gy, the maximum level of MN reduction rate caused by NAGE and WR-1065 was 53.8% and 59.2%, respectively; after 2 Gy irradiation, it was 37.3% and 42%, respectively; (3) the MN distribution in PBL followed a non-Poisson distribution in all cases; and (4) both NAGE and WR-1065 showed no significant effect on the proliferation index of lymphocytes. The results indicate that NAGE is a relatively non-toxic natural product, which can be administered as a dietary supplement and has the potential to be a radiation countermeasure.  相似文献   
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OBJECTIVE: We investigated whether gestational diabetes mellitus is associated with monocyte-chemoattractant-protein-1 (MCP-1) and soluble CD40 ligand (sCD40L), the functional relevant proteins in the inflammatory process. METHODS: In all 32 women with gestational diabetes mellitus, 18 women without gestational diabetes mellitus and 40 nonpregnant women were included. MCP-1 and sCD40L were measured at the time of the oral glucose tolerance test (second trimester), in the third trimester and postpartum. RESULTS: MCP-1 was higher in pregnant women (women with gestational diabetes mellitus and without) than in nonpregnant women (p < 0.001) in the third trimester, and also in the second trimester and postpartum. MCP-1 was elevated in patients with gestational diabetes mellitus in the third trimester compared to healthy pregnant women (p = 0.007). In gestational diabetes mellitus, MCP-1 increased from the second to the third trimester (p = 0.003). We found no association of sCD40L and gestational diabetes mellitus. CONCLUSION: The elevation of MCP-1 in the third trimester in gestational diabetes mellitus suggests an association between inflammation and GDM. Copyright (c) 2008 John Wiley & Sons, Ltd.  相似文献   
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