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Cardiopulmonary surgeries need connectors for extracorporeal circulation. The patient's blood in contact with the tube surfaces modifies its plasmatic proteins, promotes platelet aggregation, and activates the complement system, unleashing thrombus formation. Thus, it becomes necessary for an anticoagulant to keep the circuit free from these events. Heparin is the anticoagulant used even after reports about its disadvantages. Platelet adherence seems to be very dependent on the quality from the surfaces that can promote cellular proliferation, aggregation, and thrombosis. In this study, we compare the quality of the heparin-coated and uncoated surfaces. We used a blood cell culture and scanning electron microscopy (SEM) to visualize the platelet aggregation. It was concluded that there are groove areas that permit platelet adherence, and if they are not coated totally by the heparin, aggregation still occurs although in lower scale than on the uncoated tubes.  相似文献   
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In the present study, extracellular glutamate (Glu) was monitored in real time using an enzyme electrode biosensor following traumatic brain injury (TBI) either with or without inducing hypoxia in the rat. We also measured the cortical contusion volume at 3 days after insult by staining with 2,3,5-triphenyltetrazolium chloride (TTC). Male Sprague-Dawley rats (300-400 g) were anesthetized and then subjected to lateral fluid percussion (FP) brain injury of moderate severity (3.5-4.0 atm), using the Dragonfly device model (no. HPD-1700). The experimental animals were divided into four groups. Group 1 (n = 10) was subjected to TBI only, group 2 (n = 10) to TBI followed by 20 min of moderate hypoxia (FiO2: 10%), group 3 (n = 4) to 20 min of moderate hypoxia without TBI, and group 4 (n = 4) to sham. Seventy-two hours after the insults, the animals were sacrificed, their brains were stained with TTC, and the lesion volumes were calculated. A surge in the extracellular Glu concentration occurred immediately after TBI in groups 1 and 2. There was no significant difference between the two groups. Group 2 showed a prolonged efflux of Glu during hypoxia ( < 0.05). In group 3, Glu continued to show a mild increase. The cortical contusion volume in group 2 was significantly larger than that in group 1. To evaluate the possible involvement of apoptosis in groups 1 and 2, separate rats were sacrificed under the same procedures after 1, 6, 24, and 72 h after insult (n = 2/group). Immunohistochemical analysis demonstrated an increased number of both the cysteine protease caspase-3-positive cells at 24 h and TUNEL-positive cells at 72 h in group 2. These results suggest that TBI with moderate hypoxia induced the prolonged efflux of Glu, which thus resulted in more cortical damage due to necrosis and apoptosis.  相似文献   
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BACKGROUND: The use of corticosteroids or cytotoxic/immunosuppressive agents such as cyclophosphamide, chlorambucil, and cyclosporine for the treatment of frequently relapsing nephrotic syndrome (FRNS) is limited because of their adverse effects. This study was conducted to evaluate the efficacy and safety of mizoribine, a relatively new immunosuppressive drug developed in Japan, in children with FRNS. METHODS: A double-blind, placebo-controlled, multicenter trial was carried out in children, from 2 to 19 years old, with FRNS. At relapse, patients were treated with prednisolone. According to a dynamic allocation, mizoribine or a placebo was concurrently administered to each patient. Prednisolone was gradually tapered and discontinued within 12 weeks. The test drug was maintained for 48 weeks. The primary end point was the relapse rate (the total number of relapses/the total treatment days for all patients). Analyses were performed according to the intention-to-treat principle. RESULTS: The primary analysis was conducted on 99 mizoribine- and 98 placebo-treated patients. The relapse rate was lower in the mizoribine group than in the placebo group (0.0055 vs. 0.0067; ratio 0.81, 95% CI, 0.61 to 1.05, P = 0.12). The hazard ratio of the cumulative remission rate between the two groups was 0.79 (95% CI, 0. 57 to 1.08). In the subgroups consisting of patients 10 years old or younger, the relapse rate ratio between the mizoribine subgroup (54 patients) and the placebo subgroup (57 patients) was 0.66 (95% CI, 0. 44 to 0.94, P = 0.017). The hazard ratio of the cumulative remission rate between the two subgroups was 0.56 (95% CI, 0.37 to 0.85, P = 0. 007). Hyperuricemia was the most common adverse event with mizoribine (16%), but was transient. CONCLUSIONS: Compared with the placebo, mizoribine significantly decreased the relapse rate and prolonged the remission period in the subgroup consisting of patients 10 years old or younger. This drug may be useful in young children with FRNS who generally relapse more frequently than older children.  相似文献   
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OBJECTIVES: To investigate the antitumor effects of Scutellariae radix and its components baicalein, baicalin, and wogonin on human bladder cancer cell lines (KU-1 and EJ-1) and a murine bladder cancer cell line (MBT-2). METHODS: Bladder cancer cells were incubated with various concentrations of the agents. Antiproliferative activity against the bladder cancer cell lines was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diplenyl tetrazolium bromide assay. In an in vivo experiment, the mice were subcutaneously injected with MBT-2 cells, and Scutellariae radix was orally administered at a dose of 2 or 10 mg per mouse one time daily for 10 days from day 11 to day 20. RESULTS: All the drugs inhibited cell proliferation in a dose-dependent manner, but baicalin exhibited the greatest antiproliferative activity. The concentration of baicalin necessary to obtain 50% inhibition was 3.4 microg/mL for KU-1, 4.4 microg/mL for EJ-1, and 0.93 microg/mL for MBT-2. For KU-1 and MBT-2, the percentage of cell survival significantly decreased (P <0.05) at a baicalin concentration of 1 microg/mL. In an in vivo experiment, antitumor effects of Scutellariae radix on C3H/HeN mice implanted with MBT-2 were investigated. All the control mice showed a progressive increase in tumor volume, reaching 2.81 +/- 0.18 cm(3) on day 20 and 5.36 +/- 0.44 cm(3) on day 25. However, when Scutellariae radix was orally administered at a dose of 10 mg per mouse one time daily for 10 days from day 11 to day 20, the tumor volume was 1.99 +/- 0.19 cm(3) on day 20 and 3.86 +/- 0.26 cm(3) on day 25, a significant inhibition of tumor growth (P <0.05). Conclusions. These results suggest that Chinese herbal medicines may become an attractive and promising treatment for bladder cancer.  相似文献   
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