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11.
BACKGROUND/AIMS: To evaluate whether the addition of 2 weeks of ranitidine to a 1-week oral triple therapy (OTT) regimen improved ulcer healing and H. pylori eradication. METHODOLOGY: Two hundred and eleven consecutive patients with an endoscopic diagnosis of active duodenal ulcer (DU) and a positive antrum biopsy for H. pylori were enrolled. Those attending the Hospital Vera Cruz (Group A, n=142) received a 14-day course of ranitidine (150 mg after breakfast and dinner) plus a 1-week OTT, consisting of bismuth subcitrate, (240 mg after the 3 meals), tetracycline (500 mg, 10 min before the three meals and at bedtime), and furazolidone (200 mg after breakfast and dinner). Patients from the Hospital das Clinicas (Group B, n=69) received the same OTT as Group A but without ranitidine. Patients underwent endoscopy again on average 40 days (range: 30-60 days) after completing therapy in order to assess ulcer healing and H. pylori status. RESULTS: Both schedules were equally efficient in eradicating H. pylori with 90% (128/142) eradication in group A, and 84% (58/69) in group B (p=0.2). In contrast, the addition of ranitidine to OTT improved ulcer healing when compared with OTT alone (96%, 137/142, vs. 70%, 48/69; p<0.001). CONCLUSIONS: Our results demonstrate that the association of acid suppression, obtained with 2 week ranitidine administration with OTT improved ulcer healing but did not enhance H. pylori eradication.  相似文献   
12.
Various amounts of carbon black (CB) and carbon nanofibres (CNF) were dispersed in an epoxy resin to prepare nanocomposites whose mechanical behaviour, under ramp and creep conditions, was monitored by electrical measurements. The electrical resistivity of the epoxy resin was dramatically reduced by both nanofillers after the percolation threshold (1 wt% for CB and 0.5 wt% for CNF), reaching values in the range of 10(3)-10(4) omega . cm for filler loadings higher than 2 wt%. Due to the synergistic effects between the nanofillers, an epoxy system containing a total nanofiller amount of 2 wt%, with a relative CB/CNF ratio of 90/10 was selected for the specific applications. A direct correlation between the tensile strain and the increase of the electrical resistance was observed over the whole experimental range, and also the final failure of the samples was clearly detected. Creep tests confirmed the possibility to monitor the various deformational stages under constant loads, with a strong dependency from the temperature and the applied stress. The obtained results are encouraging for a possible application of nanomodified epoxy resin as a matrix for the preparation of structural composites with sensing (i.e., damage-monitoring) capabilities.  相似文献   
13.
Acute pancreatitis is only rarely the first presentation of a cystic neoplasm of the pancreas. Mucinous cystadenomas have not been reported to be a cause of acute pancreatitis; however, we present two cases of mucinous cystadenoma of the pancreas which have caused acute pancreatitis. Both patients (female) presented acute abdominal pain, with serum amylase elevation and ultrasound scan (US) and computed tomography (CT) evidence of moderate pancreatitis, which resolved with medical treatment; fluid collection in the distal pancreas had been misinterpreted as a pseudocyst. There was no history of alcohol abuse or gallstone disease. After distal pancreatectomy the diagnosis of mucinous cystadenoma was confirmed; in one case a large pseudocyst was associated with this diagnosis. Pre-operative differential diagnosis between inflammatory and neoplastic cysts is difficult, especially when the patient's first presentation is due to an episode of acute pancreatitis. A neoplastic cyst should be considered when acute pancreatitis attacks occur in non-alcoholic women, who do not have gallstone disease.  相似文献   
14.

Water stress conditions associated with population growth, climate change, and groundwater contamination, represent a significant challenge for all stakeholders in the water sector. Increasing the resilience of Water Supply Systems (WSSs) becomes of fundamental importance: along with an adequate level of service, sustainability targets must be ensured. A long-term management strategy is strictly connected to a holistic approach, based on analyses at different scales. To this end, both groundwater modeling tools and water management models, with different spatial and temporal scales, are routinely and independently employed. Here, we propose a coupled approach combining: i) groundwater models (MODFLOW) to investigate different stress scenarios, involving climate change and anthropic activities; ii) water management models (Aquator), to assess the water resources availability and the best long-term management strategy for large-scale WSS. The management models are implemented starting from input and output flows derived by groundwater models: this leads to establish a comprehensive framework usually not defined in management models and including a quantitative characterization of the aquifer. The proposed methodology, general and applicable to any study area, is here implemented to the WSS of Reggio Emilia Province, and its main groundwater resource, the Enza aquifer, considering three different stress scenarios for groundwater models (BAU, ST1, and ST2), and for management strategies (BAU, BAURV2, ST2). Among the key results, we observe that coupling the two model types: i) allows evaluating water resources availability in connection with management rules; ii) leads to examining more realistic operation choices; iii) permits planning of infrastructures at basin scale.

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15.
The main focus of this study is to characterize the interfacial interactions between silica nanoparticles and polypropylene and to investigate how the surface properties and morphology of the silica nanoparticles affect the elastic response of the silica–polypropylene composites. The composites were prepared by melt compounding and injection molding. Both non‐functionalized and dimethyldichlorosilane‐functionalized silica nanoparticles were used. Three‐component composites were also prepared by including selected formulations of both poly(propylene‐g‐maleic anhydride) copolymer (PPgMA) and different types of silica. It was found that both silica types are nucleating agents for PP and significantly alter its crystallization behavior. A strong correlation between the glass transition temperature (Tg) and the tensile modulus in silica‐PP nanocomposites indicated the presence of a secondary reinforcing mechanism that is the pinning of the polymer chains on the silica surface. The presence of a complex constrained phase, represented by immobilized amorphous and transcrystalline phases, forming at the filler surface, was assessed by modulated differential scanning calorimetry and dynamic mechanical analysis. Finally, the interfacial interactions were correlated to the tensile and viscoelastic properties using the theoretical models proposed by Pukanszky and Sumita et al., respectively, and comparing the predictions of the models to experimental results. POLYM. COMPOS., 37:2018–2026, 2016. © 2015 Society of Plastics Engineers  相似文献   
16.
The Institute CIM for Sustainable Innovation (ICIMSI), being part of the University of Applied Sciences and Arts of Southern Switzerland (SUPSI), supports local industrial and service sectors through knowledge creation and transfer. In this framework, ICIMSI develops various initiatives in engineering education and learning both concerning continuous education and higher education. The paper presents the strategy followed by ICIMSI in each of these initiatives as well as the level and type of involvement of the industrial partners. The courses genesis, their structure and their contents are also pointed out.  相似文献   
17.
Between 1988 and 1994, eighty-eight trapeziometacarpal arthroplasties were performed on eighty-four patients (69 females and 15 males), with a mean age of 61 years (37 to 81). Forty-five Ledoux and forty-three De la Caffinière prosthesis were implanted. Of the 61 non-reoperated prosthesis, 51 were reviewed with a mean follow-up of 25 months for the Ledoux prosthesis and 63 months for the De la Caffinière prosthesis. Survival rate was 58.8% at 16 months for the Ledoux prosthesis and 66.4% at 68 months for the De la Caffinière prosthesis, with a statistically significant difference (p < 0.001). In the Ledoux group, 15% of the shafts and 46% of the cups were loose. In the De la Caffinière group 24% of the shafts and 28% of the cups were loose. The final outcome of both prosthesis was similar, and we therefore concluded that spherical prostheses fixed in the trapezium are inadequate for the trapeziometacarpal joint.  相似文献   
18.
19.
OBJECTIVES: The most used therapeutic schedule to eradicate Helicobacter pylori is the "triple therapy," which is based on the simultaneous use of a bismuth salt and two antibiotics. Sucralfate, a basic aluminum salt of sucrose sulfate, is supposed to have an antibacterial activity and is said to reduce the bacterial density of H. pylori. This randomized, prospective clinical trial compares the efficacy of an alternative oral triple therapy consisting of sucralfate, tinidazol, and tetracycline with a conventional therapy using ranitidine, with respect to H. pylori eradication and duodenal ulcer healing and recurrence in a 12-month follow-up. METHODS: Forty-three patients with active duodenal ulcers diagnosed at endoscopy were enrolled to receive either 1 g of sucralfate four times daily for 30 days, 500 mg of tetracycline four times daily, and 500 mg of tinidazol three times daily, for 10 days (group A; n = 23) or 150 mg of ranitidine twice daily for 30 days (group B; n = 20). The groups were age- and sex-matched and balanced for tobacco use and H. pylori status. Compliance assessed by post-treatment interviews was considered high (all patients declared that they had ingested at least 80% of the drugs). RESULTS: Both therapies were efficient in healing ulcers (group A, 95%; group B, 90%), the relapse rates were high in both groups (group A, 77%; group B, 89%), and the alternative triple therapy eradicated H. pylori in only 4% of the patients. CONCLUSION: Alternative oral triple therapy presented no significant advantage over ranitidine treatment of active ulcer disease.  相似文献   
20.
The differential diagnosis of recurrent hepatitis C following orthotopic liver transplantation (OLT) may be difficult. We evaluated the diagnostic significance of IgM anti-hepatitis C virus (anti-HCV) core antibodies in 27 patients undergoing OLT because of HCV-associated cirrhosis. Serial serum samples collected before and after OLT were tested for the presence of IgM anti-HCV core antibodies. Results were compared with the histological evidence of liver damage, the presence, level, and genotype of serum HCV RNA and the degree of immunosuppression. All patients underwent recurrent HCV infection. Recurrent hepatitis was diagnosed histologically in 21 patients an average of 48 weeks after OLT (range 2-209 weeks): 18 had persistence or (re-)appearance of the IgM anti-HCV core after OLT, one lost the IgM anti-HCV core after OLT, and two never secreted IgM anti-HCV core either before or after OLT. The remaining six patients did not develop recurrent hepatitis after a follow-up of 44-241 weeks from OLT; in these patients, IgM anti-HCV core either disappeared (1 case) or decreased (1 case) after OLT or were persistently negative throughout the study (4 cases). Thus, 18/21 patients with recurrent hepatitis, but only one of six without recurrent hepatitis, secreted IgM anti-HCV core after OLT (P < 0.05). The IgM anti-HCV core levels were not correlated with the level or genotype of serum HCV RNA or the degree of immunosuppression. In conclusion, secretion of IgM anti-HCV core antibodies after OLT seems associated with recurrence of HCV-associated liver disease and may have diagnostic significance.  相似文献   
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