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61.
Objectives: Recently, both the number and the complexity with associated increased technical difficulty of therapeutic ERCP procedures have significantly increased resulting in longer procedural and fluoroscopy times. During ERCP, the patient is exposed to ionizing radiation and the consequent radiation dose depends on multiple factors. The aim of this study was to identify factors affecting fluoroscopy time and radiation dose in patients undergoing ERCP.

Materials and methods: Data related to patient demographics, procedural characteristics and radiation exposure in ERCP procedures (n?=?638) performed between August 2013 and August 2015 was retrospectively reviewed and analyzed. Statistically significant factors identified by univariate analyses were included in multivariate analysis with fluoroscopy time (FT) and dose area product (DAP) as dependent variables. Effective dose (ED) was estimated from DAP measurements using conversion coefficient.

Results: The factors independently associated with increased DAP during ERCP were age, gender, radiographer, complexity level of ERCP, cannulation difficulty grade, bile duct injury and biliary stent placement. In multivariate analysis the endoscopist, the complexity level of ERCP, cannulation difficulty grade, pancreatic duct leakage, bile duct dilatation and brushing were identified as predictors for a longer FT. The mean DAP, FT, number of acquired images and ED for all ERCP procedures were 2.33 Gy·cm2, 1.84?min, 3 and 0.61 mSv, respectively.

Conclusions: Multiple factors had an effect on DAP and FT in ERCP. The awareness of these factors may help to predict possible prolonged procedures causing a higher radiation dose to the patient and thus facilitate the use of appropriate precautions.  相似文献   
62.
This paper presents the impact of accelerated aging on selected mechanical and thermal properties of isotactic polypropylene (iPP) composites filled with sedimentary hybrid natural filler-Opoka rock. The filler was used in two forms: an industrial raw material originating as a subsieve fraction natural material, and a rock calcinated at 1000 °C for production of phosphorous sorbents. Fillers were incorporated with constant amount of 5 wt % of the resulting composite, and the material was subjected to accelerated weathering tests with different exposition times. The neat polypropylene and composites with calcium carbonate as a reference filler material were used for comparison. The aim of the research was to determine the possibility of using the Opoka rock as a new hybrid filler for polypropylene, which could be an alternative to the widely used calcium carbonate and silica. The thermal, mechanical, and structural properties were evaluated by means of differential scanning calorimetry (DSC), tensile tests, scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy with attenuated total reflectance (FTIR/ATR) prior to and after accelerated aging. As a result, it was found that the composites of polypropylene with Opoka were characterized by similar or higher functional properties and higher resistance to photodegradation compared to composites with conventional calcium carbonate. The results of measurements of mechanical properties, structural and surface changes, and the carbonyl index as a function of accelerated aging proved that Opoka was an effective ultraviolet (UV) stabilizer, significantly exceeding the reference calcium carbonate in this respect. The new hybrid filler of natural origin in the form of Opoka can therefore be used not only as a typical powder filler, but above all as a UV blocker/stabilizer, thus extending the life of polypropylene composites, especially for outdoor applications.  相似文献   
63.
In this study, syntheses of acrylate copolymers were performed based on the monomers butyl acrylate (BA), 2-ethylhexyl acrylate (2-EHA), and acrylic acid (AA) and the second-type unsaturated photoinitiator 4-acryloyloxybenzophenone (ABP). The structure of the obtained copolymers was confirmed via FT-IR spectroscopic analysis, and the viscosity and the content of non-volatile substances were determined. The adhesive films were then coated and cross-linked using ultraviolet radiation in the UV-C range at various doses (5–50 mJ/cm2). Due to the dependence of the self-adhesive properties of the adhesive layer on the basis weight, various basis weights of the layer in the range of 30–120 g/m2 were tested. Finally, the self-adhesive properties were assessed: tack, peel adhesion, shear strength (cohesion) at 20 °C and 70 °C, as well as the SAFT test and shrinkage. The aim of the study was to determine the effect of the type of monomer used, the dose of ultraviolet radiation, and the basis weight on the self-adhesive and usable properties of the obtained self-adhesive tapes.  相似文献   
64.
Objective. The analysis of genetic markers of rheumatoid arthritis (RA) in a population in which the DR4 serotype is not strongly associated with the disease. Methods. Chilean RA patients (56 seropositive and 22 seronegative) and 141 controls were studied by serotyping. Southern blot analysis of Bam HI restriction fragment length polymorphism (RFLP) was done in genomic DNA from 46 patients with seropositive RA, 17 patients with seronegative RA, and 45 controls, using a complementary DNA probe specific for DRB1 genes. Results. The prevalence of the HLA—DR9 haplotype was strikingly higher in seropositive RA patients (21%) than in controls (3%) (Pcorr < 0.0008, by Fisher's exact test; relative risk [RR] = 9.34). The prevalence of DR4 and DR1 haplotypes, although slightly increased, did not achieve a significant preponderance. The simultaneous presence of two Bam HI fragments (3.6 kb and 4.5 kb) was found with higher prevalence in seropositive patients (83%; RR = 9; Pcorr < 0.00002) than in controls (36%), and seemed higher in seronegative RA patients as well (71%; RR = 4). Furthermore, its prevalence remained increased in comparisons of DR4 positive controls (36%) with DR4 positive seropositive patients (100%; RR = 67; Pcorr < 0.0002) and DR4 positive seronegative patients (100%; RR = 36; Pcorr < 0.006), even after excluding the DR9 positive individuals. A tendency toward higher association with DR1 seropositive RA patients (67%; RR = 12), a group with no DR4 or DR9 positive individuals, than in DR1 positive controls (14%), was also observed. Conclusion. The HLA—DR9 haplotype was definitively consolidated as a very strong genetic marker exclusively for seropositive RA in Chilean patients, as suggested by our previous observations. RFLP analysis showed that the simultaneous presence of 3.6-kb and 4.5-kb Bam HI fragments constituted a better RA marker than did any of the heretofore studied haplotypes. These fragments together would be linked to RA independently of the DR1, DR4, and DR9 haplotypes. The overall evidence indicates that Chilean seropositive RA patients display a genetic background that is different from that underlying RA susceptibility in other populations and suggests the existence of common, as well as distinct, genetic elements predisposing to seronegative and seropositive RA.  相似文献   
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68.
Suppressed immune status facilitates immune escape mechanisms that allow chronic lymphocytic leukemia cells to proliferate and expand. The expression of HLA-G could effectively inhibit the immune response. In immune response inhibitory signals follow activation of immune system which might be occur during bacterial or viral infection in CLL patients. In the current study we characterized two components of immune system, inhibitory molecule HLA-G with its receptor – CD85j and Toll-like receptor 9.  相似文献   
69.

Background

The long-term efficacy of laparoscopic Roux-en-Y gastric bypass (RYGB) in the treatment of morbid obesity has been demonstrated. Laparoscopic sleeve gastrectomy (SG) as a single procedure has shown promising short-term results, but the long-term efficacy of SG has not yet been demonstrated. The aim of this study was to determine the preliminary 30-day morbidity and mortality of RYGB and SG in a prospective multicenter randomized setting.

Methods

A total of 240 morbidly obese (BMI?=?35–66?kg/m2) patients evaluated by a multidisciplinary team were randomized to undergo either RYGB or SG. There were 117 patients in the RYGB group and 121 in the SG group; two patients had to be excluded after randomization. Both study groups were comparable regarding age, gender, BMI, and comorbidities.

Results

There was no 30-day mortality. The median operating time was significantly shorter in the SG group (66?min vs. 94?min, p?p?=?0.292). Nine (7.4 %) SG patients and 20 (17.1 %) RYGB patients had minor complications (p?=?0.023). The overall morbidity was 13.2 % after SG and 26.5 % after RYGB (p?=?0.010). There were three (2.5 %) early reoperations after SG and four (3.3 %) after RYGB (p?=?0.719).

Conclusions

At 30-day analysis SG is associated with a shorter operating time and fewer early minor complications compared to RYGB. There were no significant differences in major complications or early reoperations. Long-term follow-up is required to determine the effect on weight loss, resolution of obesity-related comorbidities, and improvement of quality of life.  相似文献   
70.
Even in experienced hands, a common problem at endoscopic retrograde cholangiopancreatography (ERCP) is difficulty in reaching a selective cannulation of the common bile duct or pancreatic duct. The success rate of biliary cannulation has improved markedly in many centers after the adoption of double-guidewire-assisted cannulation technique in cases in which the guidewire repeatedly passes into the pancreatic duct although the common bile duct is intended. Here, we describe 2 novel applications of the double-guidewire technique for difficult cannulation in ERCP. In particular, we emphasize that in addition to difficult biliary cannulation, double-guidewire technique may prove useful in difficult pancreatic cannulation. The double-guidewire technique is feasible also in cases in which the guidewire repeatedly passes into the cystic duct instead of the intended common hepatic duct and intrahepatic radicals. ERCP endoscopists should be aware of all modifications of double-guidewire technique to further increase the success rates of selective cannulations in ERCP.  相似文献   
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