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51.
BACKGROUND/AIMS: Antibiotic resistance and poor compliance are the main causes of Helicobacter pylori (H. pylori) eradication failure. This study evaluated the eradication rate, tolerability, and compliance of levofloxacin- azithromycin combined triple therapy for H. pylori eradication. METHODS: 1) First-line eradication: A total of 78 H. pylori-positive patients were enrolled. Seventeen military men in Armed Forces Capital Hospital were treated with 7 days of levofloxacin-azithromycin combined triple therapy (omeprazole 20 mg bid, levofloxacin 500 mg od, and azithromycin 500 mg od), and 61 patients in Kangbuk Samsung Hospital were treated with standard PPI-based triple therapy (omeprazole 20 mg bid, amoxicillin 1.0 g bid, and clarithromycin 500 mg bid) for 7 days. 2) Second-line eradication: A consecutive series of 59 patients who failed H. pylori eradication with standard PPI-based triple therapy in Kangbuk Samsung Hospital were randomized to two groups. Thirty patients were retreated with 7 days of bismuth-based quadruple therapy (omeprazole 20 mg bid, bismuth 120 mg qid, metronidazole 500 mg tid, and tetracycline 500 mg qid), and remaining 29 patients were retreated with levofloxacin-azithromycin combined triple therapy. Patient's compliance and tolerability were evaluated at the end of treatment. The status of H. pylori infection was assessed 8 weeks later then. The successful eradication of H. pylori was defined as negative results from histology and CLO test, or 13C-urea breath test. RESULTS: First-line eradication rate of levofloxacin-azithromycin triple therapy was lower than that of standard PPI-based triple therapy, but there was no statistically significant difference (70.6% vs. 80.3%, p=0.390). Second-line eradication rate of levofloxacin-azithromycin combined triple therapy was significantly lower than that of bismuth-based quadruple therapy (ITT/PP 65.5%/73.1% vs. 90%/90%, p<0.0001). The compliances of all patients were more than 85%. Two of patients with levofloxacin-azithromycin combined triple therapy complained self-limiting side effects (mild dizziness; mild insomnia with general weakness). CONCLUSIONS: Levofloxacin-azithromycin combined triple therapy should not be recommended as the first-line or second-line H. pylori eradication regimen in Korea.  相似文献   
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OBJECTIVES: The aim of the study was to determine whether coronary stenosis can be detected and myocardial viability assessed after myocardial infarction from a single venous bolus injection of BR14, a new ultrasound contrast agent. BACKGROUND: BR14 is an ultrasound contrast agent that, like (201)Tl, demonstrates redistribution. Whether this principle can be used to determine myocardial viability is not known. METHODS: Non-critical (n = 6) or flow-limiting (n = 4) stenoses were placed on coronary arteries of 10 open-chest dogs, which then underwent 2 h of coronary occlusion followed by reperfusion through the stenosis. Hyperemia was induced to create flow mismatch in the dogs with non-critical stenosis. Hyperemia was not induced in dogs with reduced resting coronary blood flow. All dogs were given 2 ml of BR14 as a bolus injection and serial images were obtained. Myocardial blood flow (MBF) was measured using radiolabeled microspheres. At the end of the experiment, tissue staining was performed to determine infarct size and topography. RESULTS: Initial images demonstrated flow mismatch between the normal bed and that subtended by the stenosis (during hyperemia in dogs without critical stenosis and during rest in those with reduced resting MBF). The perfusion defect size correlated well with radiolabeled microsphere-derived hypoperfused zone (r = 0.89). Regions within the hypoperfused zone that had not undergone necrosis showed redistribution, whereas the necrotic regions showed a persistent defect, the size of which correlated well with infarct size (r = 0.80). CONCLUSIONS: Because of its ability to redistribute, BR14 can define regions of relative hypoperfusion and also discriminate between infarcted and viable tissue within the hypoperfused zone after a single venous injection. This property lends itself to assessing myocardial perfusion during exercise stress.  相似文献   
54.
Gastric tuberculosis presenting as a submucosal tumor   总被引:1,自引:0,他引:1  
  相似文献   
55.
Probing the surface morphology of microthin fibers such as naturally occurring biofibers is essential for understanding their structural properties, biological function, and mechanical performance. The state-of-the-art methods for studying the surfaces of biofibers are atomic force microscopy imaging and scanning electron microscopy, which well characterize surface geometry of the fibers but provide little information on the local interaction potential of the fibers with the surrounding material. In contrast, complex nematic fluids respond very well to external fields and change their optical properties upon such stimuli. Here we demonstrate that liquid crystal droplets deposited on microthin biofibers—including spider silk and cellulosic fibers—reveal characteristics of the fibers’ surface, performing as simple but sensitive surface sensors. By combining experiments and numerical modeling, different types of fibers are identified through the fiber-to-nematic droplet interactions, including perpendicular and axial or helicoidal planar molecular alignment. Spider silks align nematic molecules parallel to fibers or perpendicular to them, whereas cellulose aligns the molecules unidirectionally or helicoidally along the fibers, indicating notably different surface interactions. The nematic droplets as sensors thus directly reveal chirality of cellulosic fibers. Different fiber entanglements can be identified by depositing droplets exactly at the fiber crossings. More generally, the presented method can be used as a simple but powerful approach for probing the surface properties of small-size bioobjects, opening a route to their precise characterization.Natural microfilaments produced by plants, insects, or spiders are fascinating materials not just because of their specific properties such as wear resistance, elasticity, tensile strength, and toughness (15) but also because of their microorganization (69). Their macroscopic properties can match properties of materials like kevlar but are at the same time biocompatible and biodegradable (10). These fascinating macroscopic properties actually originate from bulk and surface properties of the fibers (1). The chemical composition of the threads combined with their morphology determines the final properties of the material (1113). The mechanical properties of the spider fibers are determined by the existence of a lyotropic liquid crystalline phase, from which the threads are drawn (14). Such silks are known to include nanoscale networks of defects and cavities that yield surface structures notably dependent on the spider species (3). These differences do not affect much the mechanical performance of the fibers (1, 3, 5). From a technological perspective, many attempts have been made to reproduce these natural bionetworks (1517). In fact cellulose-based fibers with few micrometers of diameter, produced by electrospinning, can also acquire different morphologies depending upon the processing conditions, giving diverse features of the final threads and mats (18). Therefore, probing the surface structure of the microfibers is crucial for a complete understanding of their individual and interthreaded properties.From another perspective, nematic complex fluids are materials which are inherently responsive to diverse external stimuli, notably including diverse surface interactions which in the literature are known as the surface anchoring (19). Being effectively elastic materials, the orientational order of nematics responds on long, typically micrometer scales (2022), which results in a spatially varying birefringence that can be optically detected (23). Recently, it was demonstrated that glass fibers induce numerous defects in a well-aligned nematic liquid crystal cell and thus provide a simple illustration of topological phenomena (24). It is also known that liquid crystal droplets can considerably change their structure by the action of otherwise imperceptibly small external stimuli (21). Pierced nematic and chiral nematic droplets develop defects that can be controlled by the liquid crystal elasticity, chirality, and surface boundary conditions (25, 26) indicating exceptional sensitivity. Therefore, to generalize, putting nematics into contact with diverse surfaces (18, 27) can be used as a simple but very powerful technique to detect the surface properties of microobjects such as biological fibers.In this paper we demonstrate the surface morphology sensing of biorelevant fibers, including spider silk and cellulosic microfibers, by nematic droplets that are sprayed onto the fibers. Specifically, we explore the chiral and achiral nature of the fiber’s surface and the in-plane or perpendicular alignment fields the fibers impose on the nematic. Droplets with degenerate in-plane and perpendicular alignment of the nematic at their free surfaces are explored, combining experiments and numerical modeling, to allow for tuning of the sensing precision. Further, the entanglement sites of the fiber webs are explored, with the droplets deposited at the sites clearly revealing contact, noncontact, and entangled morphologies.  相似文献   
56.
Background:Supraglottic airway (SGA) devices do not definitively protect the airway from regurgitation of gastric contents. Increased gastric pressure and long operation time are associated with development of complications such as aspiration pneumonia. The aim of this study was to compare intragastric pressure between second-generation SGA and endotracheal tube (ETT) devices during long-duration laparoscopic hepatectomy.Methods:A total of 66 patients was randomly assigned to 2 groups; 33 patients each in the ETT and SGA groups. Intragastric pressure was continuously measured via a gastric drainage tube with a three-way stopcock connected to the pressure monitoring device. Normal saline was added to the end of the gastric drainage tube at each operation time point.Results:Intragastric pressure during pneumoperitoneum was no different between the 2 groups (P = .146) or over time (P = .094). The mean (standard deviation [SD]) pH of the SGA tip measured after operation was 6.7 (0.4), and a pH <4 was not observed. Relative risk of postoperative complications was significantly higher in the ETT group relative to the SGA group (sore throat, 5.5; cough,13.0).Conclusions:Use of SGA devices does not further increase intragastric pressure, even during prolonged upper abdominal laparoscopic surgery. Also, the frequency of postoperative sore throat and cough was significantly lower when the second-generation SGA device was used.  相似文献   
57.
Inflammation is involved in numerous diseases including cancer. Inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) play important roles in the development of certain inflammatory diseases. Eupatorium makinoi, which belongs to a family of Asteraceae plants, is used medicinally in East Asia. We investigated the effects of an ethanol extract of E. makinoi (EEM) on nuclear factor-kappa B (NF-κB) activation and the expression of iNOS and COX-2 with lipopolysaccharide (TLR4 agonist) in murine macrophages. EEM suppressed NF-κB activation and iNOS and COX-2 expression induced by LPS. These results suggest that EEM may regulate TLR4 signalling pathways and this may be a useful strategy for anti-inflammatory therapies.  相似文献   
58.
59.
Cosmetic facial filler-related ophthalmic artery occlusion is rare but is a devastating complication, while the exact pathophysiology is still elusive. Cerebral angiography provides more detailed information on blood flow of ophthalmic artery as well as surrounding orbital area which cannot be covered by fundus fluorescein angiography. This study aimed to evaluate cerebral angiographic features of cosmetic facial filler-related ophthalmic artery occlusion patients. We retrospectively reviewed cerebral angiography of 7 patients (4 hyaluronic acid [HA] and 3 autologous fat-injected cases) showing ophthalmic artery and its branches occlusion after cosmetic facial filler injections, and underwent intra-arterial thrombolysis. On selective ophthalmic artery angiograms, all fat-injected patients showed a large filling defect on the proximal ophthalmic artery, whereas the HA-injected patients showed occlusion of the distal branches of the ophthalmic artery. Three HA-injected patients revealed diminished distal runoff of the internal maxillary and facial arteries, which clinically corresponded with skin necrosis. However, all fat-injected patients and one HA-injected patient who were immediately treated with subcutaneous hyaluronidase injection showed preserved distal runoff of the internal maxillary and facial arteries and mild skin problems. The size difference between injected materials seems to be associated with different angiographic findings. Autologous fat is more prone to obstruct proximal part of ophthalmic artery, whereas HA obstructs distal branches. In addition, hydrophilic and volume-expansion property of HA might exacerbate blood flow on injected area, which is also related to skin necrosis. Intra-arterial thrombolysis has a limited role in reconstituting blood flow or regaining vision in cosmetic facial filler-associated ophthalmic artery occlusions.  相似文献   
60.
We conducted this study to investigate the synergistic effect of human urine-derived stem cells (USCs) and surface modified composite scaffold for bladder reconstruction in a rat model. The composite scaffold (Polycaprolactone/Pluronic F127/3 wt% bladder submucosa matrix) was fabricated using an immersion precipitation method, and heparin was immobilized on the surface via covalent conjugation. Basic fibroblast growth factor (bFGF) was loaded onto the heparin-immobilized scaffold by a simple dipping method. In maximal bladder capacity and compliance analysis at 8 weeks post operation, the USCs-scaffoldheparin-bFGF group showed significant functional improvement (2.34 ± 0.25 mL and 55.09 ± 11.81 µL/cm H2O) compared to the other groups (2.60 ± 0.23 mL and 56.14 ± 9.00 µL/cm H2O for the control group, 1.46 ± 0.18 mL and 34.27 ± 4.42 µL/cm H2O for the partial cystectomy group, 1.76 ± 0.22 mL and 35.62 ± 6.69 µL/cm H2O for the scaffold group, and 1.92 ± 0.29 mL and 40.74 ± 7.88 µL/cm H2O for the scaffoldheparin-bFGF group, respectively). In histological and immunohistochemical analysis, the USC-scaffoldheparin-bFGF group showed pronounced, well-differentiated, and organized smooth muscle bundle formation, a multi-layered and pan-cytokeratin-positive urothelium, and high condensation of submucosal area. The USCs seeded scaffoldheparin-bFGF exhibits significantly increased bladder capacity, compliance, regeneration of smooth muscle tissue, multi-layered urothelium, and condensed submucosa layers at the in vivo study.  相似文献   
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