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991.
Introduction Recent advances in our understanding of the pathophysiological and molecular mechanisms involved in pulmonary arterial hypertension have led to the development of novel and rational pharmacological therapies. In addition to conventional therapy (i.e., supplemental oxygen and calcium channel blockers), prostacyclin or endothelin receptor antagonists have been recommended as a first-line therapy for pulmonary arterial hypertension. However, these treatments have potential limitations with regard to their long-term efficacy and improvement in survival. Furthermore, intravenous prostacyclin (epoprostenol) therapy, which is recommended by most experts for patients with New York Heart Association (NYHA) functional class IV, is complicated, uncomfortable for patients, and expensive because of the cumbersome administration system. Considering these circumstances, it is necessary to develop additional novel therapeutic approaches that target the various components of this multifactorial disease. Case report In this short review, we present an overview of the current treatment options for pulmonary arterial hypertension and describe a case report with primary pulmonary hypertension. A male patient with NYHA functional class IV and showing no response to calcium channel blockers and prostacyclin exhibited significantly improved exercise tolerance and hemodynamics and long-term survival for more than 2.5 years after receiving an oral combination therapy of a phosphodiesterase type 5 inhibitor (sildenafil), phosphodiesterase type 3 inhibitor (pimobendan), and nicorandil. Future perspective We also discuss the background and plausible potential mechanisms involved in this case, as well as future perspectives in the treatment of pulmonary arterial hypertension.  相似文献   
992.
993.
ObjectivesTo examine the torque moment that occurs between esthetic brackets and bendable alloy (stainless steel [SS], titanium-molybdenum [Ti-Mo], and titanium-niobium [Ti-Nb]) wires.Materials and MethodsThis study examined ceramic (CR), zirconium oxide (ZC), polycarbonate (PC), and conventional metallic brackets (MT) (upper, 0.018-inch and 0.022-inch slots) combined with SS, Ti-Mo, and Ti-Nb wires using elastic module ligation. The torque moments delivered by various wire and bracket combinations were measured using a torque gauge apparatus. The wire torque angles at 5–40° were examined.ResultsThe torque value increased in the order of CR, ZC, MT, and PC brackets for both 0.018-inch and 0.022-inch slots. The fracture points of the CR and ZC brackets combined with SS and Ti-Mo wires were approximately more than 30° and 35°, respectively. No fracture points were detected in the combination of ZC brackets and Ti-Nb wires.ConclusionsThe current study identified the material characteristics of CR, ZR, and PC brackets during torque tooth movements. The present results demonstrate a characteristic combined effect between different esthetic brackets and bendable alloy wires.  相似文献   
994.
995.
Tendency of isolated bacteria from infections in abdominal surgery during the period from April 2005 to March 2006 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 384 strains including 18 strains of Candida spp. were isolated from 161 (70.3%) of 229 patients with surgical infections. One hundred and ninty-five strains were isolated from primary infections, and 171 strains were isolated from postoperative infections. From primary infections, aerobic Gram-negative bacteria and aerobic Gram-positive bacteria were predominant, while aerobic Gram-positive bacteria were predominant from postoperative infections. The isolation rate of aerobic Gram-positive bacteria, such as Enterococcus spp. and Staphylococcus aureus were higher from both types of infections. Among anaerobic Gram-positive bacteria, the isolation rate of Peptostreptococcus spp. was the highest from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Pseudomonas aeruginosa, Klebsiella spp. in this order, and from postoperative infections, E. coli was the most predominantly isolated, followed by Klebsiella pneumoniae and P. aeruginosa. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both primary and postoperative infections. In this series, we noticed no vancomycin-resistant Gram-positive cocci, nor multidrug-resistant P. aeruginosa. But cefazolin-resistant E. coli producing extended spectrum fl-lactamase was seen in 5.0 per cents. We should be carefully followed up the facts that the increasing isolation rates of B. fragilis group and Bilophila wadsworthia which were resistant to both penicillins and cephems.  相似文献   
996.
Background & AIM: To make the endoscopic characteristics and clinical appearance of refractory ulcerative colitis (UC) clear, we studied the frequency and location of refractory lesions of severe UC patients. Methods: The subjects were a total of 68 patients with severe UC. 41patients were identified with refractory UC, defined as poor response to high-dose systemic steroids (SH-resistant UC), and another group of 27 patients had non-refractory UC (SH-responsive UC). Two groups were compared by the following item; endoscopic findings, locations, effect of treatment, and relation to CMV infection. Results: In SH-resistant UC, longitudinal ulcer and extensive mucosal abrasion were found with high frequency, and there were refractory lesion significantly in proximal colon. In case of UC with refractory lesion, there is a high possibility that treatment is ineffective. Of 14 UC patients with refractory lesion treated with LCAP, 10 obtained remission, whereas only 12 of 30 those patients with treated by only steroids achieved remission. Of 11 steroid-refractory UC patients with CMV detected, were refractory to steroids and had undergone. Conclusions: The findings of this study suggest that it is very important to decide on a patient’s medication by relying on exact diagnosis concerning the condition of UC by endoscopy. Received 20 July 2006; accepted 22 August 2006  相似文献   
997.
998.
BACKGROUND: 4-[3,5-Bis (trimethylsilyl) benzamido] benzoic acid (TAC-101) is a novel retinobenzoic acid derivative which has a specific binding affinity to the retinoic acid receptors (RAR)alpha and RARbeta. Using time-dependent FACScan analysis, it was observed that TAC-101 induced apoptosis in a DLD-1 human colon cancer cell line. In this study, the induction of apoptosis-related proteins and the activities of caspases in a DLD-1 cell line under medication with TAC-101 were investigated. MATERIALS AND METHODS: DLD-1 cells were cultured with different concentrations of TAC-101 for 12, 24 and 48 h. The expressions of Fas, TNF-R1, DR3, bcl-2, Bax and Bid were measured using a Western blot analysis. The activities of caspase-3, -8 and -9 were measured using a colorimetric protease assay kit. RESULTS: The Western blot analysis showed that TAC-IO1 had almost no effect on the level of Bcl-2, Bax or Bid protein. Although TAC-101 did not change the expression of TNF-R1 and DR3, TAC-101 increased the expression of Fas in both a time- and a dose-dependent manner. A 3-fold increase in caspase-3 activity and a 1.5-fold increase in caspase-8 activity were observed in cells treated with TAC-101 in comparison to the control cells (p<0.01). CONCLUSION: Our data indicate that the death receptor root of the apoptotic signal transduction in DLD-1 cells mainly participates in the apoptotic induction of TAC-101. Because the compounds inducing apoptotic activity are frequent targets of cancer therapy, TAC-101 may be a good candidate for use in the treatment of colon cancer.  相似文献   
999.
Background Heat shock protein 70-2 (HSP70-2) has a cytoprotective role in various conditions and also protects the gastric mucosa. Recently, polymorphism of HSP70-2 at position 1267 was suggested to be associated with carcinogenesis. We investigated the association of this polymorphism with the risk of gastric cancer in the present study. Methods We examined 223 patients (159 men and 64 women, mean age 64.8 years) with gastric cancer who underwent gastrointestinal endoscopy at our department. The controls were 200 age-matched patients (140 men and 60 women) without gastric cancer diagnosed by gastrointestinal endoscopy. Genotyping was done by PCR-based restriction fragment length polymorphism analysis, and the PCR products were digested with PstI. The two allelic forms, corresponding to the presence or absence of the PstI site, were designated as the P1 allele and P2 allele, respectively. Logistic regression analysis was performed to calculate an odds ratios (ORs) for differences of HSP70-2 polymorphism between the two groups. Results Among the 223 patients with gastric cancer, 46 (20.6%) had P1/P1, 177 (79.4%) were P1 carriers, and 6 (2.7%) were P2/P2. In the control group, 33 (16.5%) patients had P1/P1 polymorphism, 167 (83.5%) were P1 carriers, and 12 (6.0%) were P2/P2. The OR for gastric cancer of subjects with P2/P2 polymorphism relative to P1 carriers was 0.43 (95% CI = 0.16–1.17) (P = 0.097). Among females, the OR for gastric cancer of subjects with P2/P2 polymorphism relative to P1 carriers was 0.10 (95% CI = 0.012–0.838) (P = 0.014). This polymorphism was also associated with a lower risk of middle third cancer (OR = 0.13; 95% CI = 0.02–1.00). Conclusions P2/P2 polymorphism of HSP70-2 at position 1267 was associated with a lower risk of gastric cancer in females.  相似文献   
1000.
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