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171.
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The raw material of tocopherol succinate was tested for preparation of the "Tocopherol Succinate Reference Standard (Control 981)". The analytical data obtained were: infrared spectrum same as that of the Tocopherol Succinate Reference Standard (Control 8510); specific absorbance, E(1%)1 cm (286 nm) = 40.7; thin-layer chromatography, no impurities detected until 50.0 microgram; high-performance liquid chromatography (HPLC),three impurities detected and amount of tocopherol succinate estimated to be 98.2%, loss on drying, 0.19%, assay by HPLC, 101.7%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Reference Standard (Control 981).  相似文献   
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A new technique of video-assisted thoracic sympathectomy through retrosternal pulmonary junction can be done safely using a scope guide and a flexible scope. Bilateral thoracic sympathectomy was performed, employing a single skin incision, in 18 patients with palmar hyperhidrosis. The advantages include minimal neuralgia and superior cosmesis.  相似文献   
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BACKGROUND/PURPOSE: Previous studies have shown that total parenteral nutrition (TPN) influences host immunity, but the mechanism is unclear. This study explored the effect of TPN solution on neutrophil phagocytosis and whole-blood cytokine production in response to coagulase-negative staphylococci in vitro challenge. METHODS: Blood samples were taken from five enterally fed infants (age <6 months) and six healthy adults. Samples were incubated for 45 minutes with four isovolemic solutions: (A) control (saline), (B) TPN (0.1 microL/mL of blood), (C) TPN (1 microL/mL), (D) TPN (10 microL/mL). Solution C (1 microL/mL) corresponded to TPN-blood ratio used in clinical practice. After incubation, blood was challenged with coagulase-negative staphylococci. Neutrophil phagocytosis was measured by flow cytometry after 40 minutes of bacterial challenge, and tumour necrosis factor alpha (TNF-alpha) was measured by enzyme-linked immunosorbent assay (ELISA) after 2 hours of bacterial challenge. RESULTS: In infant blood, TNF-alpha production after coagulase-negative staphylococci challenge was impaired after the addition of a "physiological" dose of TPN solution (1 microL/mL of blood) as well as "supranormal" doses (10 microL/mL of blood). In adult blood, a similar effect was observed only after the addition of a supranormal dose of TPN. In both the infant and adult blood, there was no direct effect of TPN solution on neutrophil phagocytosis. CONCLUSIONS: These results suggest that infants are more susceptible than adults to TPN-related depression of cytokine production. The level of proinflammatory cytokines may be important in the host defence against bacterial infection.  相似文献   
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Plasminogen activator (PA) expression plays an important role in smooth muscle cell (SMC) migration and may therefore contribute to mechanical force-induced arterialization of vein grafts. The aim of this study was to determine whether pulse pressure due to pulsatile flow modulates SMC migration via urokinase (u-PA)-dependent mechanisms. Using a perfused transcapillary culture system, human umbilical vein SMC were exposed to pulse pressures (0-56 mmHg), in the absence or presence of human umbilical vein endothelial cells (EC) by varying pulsatile flow rates (0 ml/min to 25 ml/min). SMC cultured in the absence of EC increased their migration following exposure to increased pulse pressure (248+/-14%). Both u-PA and matrix metallo-proteinase 1 (MMP-1) expression was significantly elevated in SMC exposed to pressure as compared to static controls. The role of proteases in the pulse pressure-induced enhancement of SMC migration was confirmed following pretreatment with aprotinin, an anti u-PA antibody and metalloproteinase inhibitors (181+/-14% for aprotinin vs. 256+/-25% for control, 108+/-4% for anti-u-PA antibody vs. 233+/-17% for non-immune IgG, and 114+/-9% for BB-94, 105+/-7% for BB-3103 vs. 222+/-5% for control). Using SMC derived from u-PA gene knock-out mice, the SMC migratory response to increased pulse pressure was completely inhibited despite a significant increase in MMP expression in these cells. These results suggest that pulse pressure due to pulsatile flow induces SMC migration in vitro via u-PA and MMP-dependent mechanisms. Moreover, u-PA gene deletion results in blunting of pressure-induced SMC migration despite the endogenous upregulation of metalloproteinase. Modulation of u-PA expression by pressure may thus represent an important mechanism whereby hemodynamic forces regulate smooth muscle cell migration.  相似文献   
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The rate of infection with TT virus (TTV), a novel single-strand DNA virus was evaluated and the clinical and laboratory features in affected Japanese medical workers were analysed. TTV DNA was measured in 356 medical workers and in 150 age-matched controls using a seminested polymerase chain reaction. TTV DNA was detected in 62 of 356 medical workers (17.4%). There were no differences in the prevalence of TTV infection between medical workers and controls (18.9%) and in the characteristics of medical workers with TTV infection and medical workers without it, except that the mean age of patients with TTV infection was higher than that of patients without TTV. The medical workers were drawn from three groups: medical doctors, nurses and clinical laboratory technicians. There was no statistically significant difference between the rate of TTV infection in the three groups. These findings suggest that the risk of TTV infection in medical workers is low and not related to liver dysfunction.  相似文献   
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