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991.
992.
The purpose of this study was to develop a new type of gene vector, polyamidoamine (PAMAM) dendriplex pharmaceutically modified, based on electrostatic interactions, by various anionic polymers. The γ-polyglutamic acid (γ-PGA)/PAMAM dendriplex and the α-PGA/PAMAM dendriplex formed a stable complex, although α-polyaspartic acid and heparin released pDNA from the complex. The addition of anionic polymer decreased the ζ-potential, although it did not greatly affect the size of the complex. As a result of an in vitro gene expression study of mouse melanoma cells, we found that the γ-PGA/PAMAM dendriplex showed high gene expression comparable to the PAMAM dendriplex, although the α-PGA/PAMAM dendriplex showed lower gene expression. Tail vein injection of the γ-PGA/PAMAM dendriplex into mice also led to high gene expression in the spleen and lung. The γ-PGA/PAMAM dendriplex showed no cytotoxicity and no agglutination, although severe cytotoxicity and agglutination were observed in the PAMAM dendriplex. Thus, we discovered that complexes of pDNA, PAMAM dendrimers, and γ-PGA showed higher gene expression in vitro and in vivo, and markedly lower toxicity. This complex is valuable and is expected to be a safe and effective gene vector.  相似文献   
993.
A novel method was developed to fabricate all-ceramic restorations which comprised CAD/CAM-fabricated machinable ceramic bonded to CAD/CAM-fabricated zirconia framework using resin cement. The feasibility of this fabrication method was assessed in this study by investigating the bonding strength of a machinable ceramic to zirconia. A machinable ceramic was bonded to a zirconia plate using three kinds of resin cements: ResiCem (RE), Panavia (PA), and Multilink (ML). Conventional porcelain-fused-to-zirconia specimens were also prepared to serve as control. Shear bond strength test (SBT) and Schwickerath crack initiation test (SCT) were carried out. SBT revealed that PA (40.42 MPa) yielded a significantly higher bonding strength than RE (28.01 MPa) and ML (18.89 MPa). SCT revealed that the bonding strengths of test groups using resin cement were significantly higher than those of Control. Notably, the bonding strengths of RE and ML were above 25 MPa even after 10,000 times of thermal cycling -adequately meeting the ISO 9693 standard for metal-ceramic restorations. These results affirmed the feasibility of the novel fabrication method, in that a CAD/CAM-fabricated machinable ceramic is bonded to a CAD/CAM-fabricated zirconia framework using a resin cement.  相似文献   
994.
Tacrolimus is a well-known potent immunosuppressant agent, which has various drug-drug or food-drug interactions. Previously, we found a renal transplant recipient who increased tacrolimus blood concentrations after ingestion of pomelo as a rare case. So, we investigated the effect of pomelo after its administration for one day or 3 consecutive days on the pharmacokinetics of tacrolimus in rats. We also confirmed the effects of grapefruit, turmeric, and ginger. The tacrolimus blood concentrations of the rats pre-treated with 100% pomelo juice were significantly higher than those pre-treated with water. On the other hand, the tacrolimus blood concentrations of the rats pre-treated with 50% pomelo juice were not significantly different from those pre-treated with water. The pomelo-tacrolimus interaction showed concentration dependency. Even low concentration of pomelo juice could enhance the blood concentrations of tacrolimus by repeated administration. The inhibitory effect of 100% pomelo juice disappeared 3 days after intake. The AUC values of tacrolimus in the rats pre-treated with grapefruit juice, ginger juice, and turmeric juice were significantly larger than those pre-treated with water. We could confirm the pomelo-tacrolimus interaction, which we discovered in a case study, quantitatively. We newly found the influence of turmeric and ginger on tacrolimus pharmacokinetics, comparable to pomelo.  相似文献   
995.
996.
Aim: The main purpose of this study was to evaluate the efficacy of paroxetine controlled‐release (CR) formulation compared to placebo. A secondary objective was to test the hypothesis that the CR decreases selective‐serotonin‐reuptake‐inhibitors‐induced nausea as its formulation allows more distal gastrointestinal absorption than the paroxetine immediate‐release (IR) formulation. Methods: We conducted this study in Japanese and Korean patients with major depressive disorder (MDD) in order to demonstrate the efficacy and safety of paroxetine CR compared with placebo. The primary efficacy end‐point was the adjusted mean change from baseline in the 17‐item Hamilton Rating Scale for Depression total score at Week 8. Results: A total of 416 patients with MDD were randomly assigned to the CR, IR and placebo groups. The mean change from baseline in the 17‐item Hamilton Rating Scale for Depression was ?12.8 in the CR group, ?12.5 in the IR group, and ?10.4 in the placebo group, which showed a statistically significant difference compared to placebo in CR (P < 0.001) and IR (P = 0.015). The incidence of adverse events was 65% in CR, 69% in IR and 55% in placebo. The adverse events were mostly mild or moderate in severity. In the early treatment period, when initiated from 12.5 mg, the incidence of nausea in the CR group was 6%, which was comparable with that of placebo (5%). Conclusion: Paroxetine CR is efficacious in the acute treatment of MDD and may have the potential benefit of decreasing the incidence of nausea in the early treatment period.  相似文献   
997.
998.
A 60-year-old man with angina was scheduled for total gastrectomy, splenectomy, and cholecystectomy. Bare-metal stents were implanted into his left anterior descending coronary artery four weeks before the operation. Aspirin and clopidogrel were administered until one week before the operation and then injection of to 15,000 units of heparin per day was given. Anesthesia was maintained with sevoflurane, remifentanil and fentanyl. At 330 minutes after starting the operation, 2-mm ST segment elevation was observed and it recovered immediately. After the operation, new 9-mm ST segment elevation in leads V2-V6 was observed. Emergent cardiac catheterization showed occlusion of the coronary artery with in-stent thrombosis. An additional stent was implanted and 10,000 units of heparin per day was injected. After five days, new stent thrombosis occurred and an additional stent was implanted. Administration of aspirin, clopidogrel and cilostazol was started immediately. Anesthesiologists should pay attention to the kind of coronary stent, consider the timing of the operation, and continue administration of aspirin.  相似文献   
999.
A 75-year-old man developed persistent dysphagia 2 months after successful total arch replacement with a long elephant trunk (ET) for a distal arch aneurysm. Enhanced computed tomography revealed not only complete thrombosis of the distal arch aneurysm, but also rapid expansion of another downstream aortic aneurysm with esophageal compression. Thoracic endovascular aortic repair was undertaken for this symptomatic aortic aneurysm, which was totally thrombo-excluded. ET might produce turbulent or jet-like blood flow from its tip in some situations and have a potential to accelerate the expansion of the downstream aneurysm. Additional endovascular ET completion is simple, effective, and less invasive.  相似文献   
1000.
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