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61.
Similar to several other countries in the world, the epidemiology of hepatitis A virus changed from high to intermediate endemicity level in Tunisia, which led to the occurrence of outbreaks. This study aimed to determine the genetic and antigenic variability of HAV strains circulating in Tunisia during the last few years. Genotyping using complete VP1 gene and VP1-2A junction confirmed the predominance of genotype IA, with co-circulation of several genetic and antigenic variants. Phylogenetic analysis including Tunisian and strains from other regions of the world showed the presence of at least two IA-variants within IA subgenotype. Amino-acid analysis showed several mutations in or close to epitope regions in the VP1-region. This study provides a baseline on the genetic and antigenic variability of HAV circulating strains before the introduction of vaccination into the national immunization schedule.  相似文献   
62.
Sewage‐based epidemiology (SBE) employs the analysis of sewage to detect and quantify drug use within a community. While SBE has been applied repeatedly for the estimation of classical illicit drugs, only few studies investigated new psychoactive substances (NPS). These compounds mimic effects of illicit drugs by introducing slight modifications to chemical structures of controlled illicit drugs. We describe the optimization, validation, and application of an analytical method using liquid chromatography coupled to positive electrospray tandem mass spectrometry (LC‐ESI‐MS/MS) for the determination of seven NPS in sewage: methoxetamine (MXE), butylone, ethylone, methylone, methiopropamine (MPA), 4‐methoxymethamphetamine (PMMA), and 4‐methoxyamphetamine (PMA). Sample preparation was performed using solid‐phase extraction (SPE) with Oasis MCX cartridges. The LC separation was done with a HILIC (150 x 3 mm, 5 µm) column which ensured good resolution of the analytes with a total run time of 19 min. The lower limit of quantification (LLOQ) was between 0.5 and 5 ng/L for all compounds. The method was validated by evaluating the following parameters: sensitivity, selectivity, linearity, accuracy, precision, recoveries and matrix effects. The method was applied on sewage samples collected from sewage treatment plants in Belgium and Switzerland in which all investigated compounds were detected, except MPA and PMA. Furthermore, a consistent presence of MXE has been observed in most of the sewage samples at levels higher than LLOQ. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
63.
Background: The aim of this study was to test the impact of hot acids etching and two types of adhesive cement on the retention of zirconia crowns. Methods: Forty maxillary premolars were prepared, and zirconia crowns were designed and fabricated with proximal extensions, then divided into 4 groups (n = 10). Group AP; the crowns were air-abraded and cemented using Panavia SA Cement. Group AL; the crowns were air- abraded and cemented using GC LinkForce. Group AHP; the crowns were air-abraded, etched with the hot acids (48% hydrofluoric acid and 69% nitric acid), and cemented using Panavia SA Cement. Group AHL; the crowns were air-abraded, etched with the hot acids, and cemented using GC LinkForce. Each zirconia crown was pre-treated and bonded to its corresponding tooth. After thermocycling (5–55 °C/10,000), the retention test was performed and the load required to dislodge the crown was reported in Newton (N), and mode of failure was recorded. The retention strength (MPa) was calculated for each tested variable and statistically analyzed. Results: Group AHP showed the highest mean value of the retention strength, followed by group AP then group AHL. Group AL showed the lowest value. A statistically significant effect (p = 0.001) of the hot acids etching on the retention of zirconia crown was found. Also, there was a significant effect (p = 0.000) of the cement type. The interaction between surface treatment and the cement type has no significant impact (p = 0.882). The main mode of failure for Panavia SA Cement is mixed mode of failure, while for G-CEM LinkForce is adhesive failure. Conclusions: Hot acid etching pre-treatment improved the retention of zirconia crown. Usage of Panavia SA Cement with hot acids etching is effective can be used for adhesive cementation of zirconia crown.  相似文献   
64.
Endoscopic biliary stent insertion is a well-established minimally invasive procedure used in the management of hepatic, biliary or pancreatic disorders. Dislocation and migration of endoscopically inserted biliary stents is a late complication; it has a reported incidence of about 7%–10% of cases. Most of the migrated stents pass naturally without complications. Very occasionally, (less than 1%), the stent becomes stuck and produces gut perforation. Very few case reports in the literature describe plastic biliary stents perforating a bowel in a hernia. Herein, we report the case of a migrated plastic biliary stent that perforated an ileal loop inside a sac of a previously uncomplicated inguinal hernia.  相似文献   
65.

Background:

The biological effects of hemostatic agends on the physiological healing process need to be tested. The aim of this study was to assess the effects of oxidized cellulose (surgicel) and bone wax on bone healing in goats’ feet.

Materials and Methods:

Three congruent circular bone defects were created on the lateral aspects of the right and left metacarpal bones of ten goats. One defect was left unfilled and acted as a control; the remaining two defects were filled with bone wax and surgicel respectively. The 10 animals were divided into two groups of 5 animals each, to be sacrificed at the 3rd and 5th week postoperatively. Histological analysis assessing quality of bone formed and micro-computed tomography (MCT) measuring the quantities of bone volume (BV) and bone density (BD) were performed. The results of MCT analysis pertaining to BV and BD were statistically analyzed using two-way analysis of variance (ANOVA) and posthoc least significant difference tests.

Results:

Histological analysis at 3 weeks showed granulation tissue with new bone formation in the control defects, active bone formation only at the borders for surgicel filled defects and fibrous encapsulation with foreign body reaction in the bone wax filled defects. At 5 weeks, the control and surgicel filled defects showed greater bone formation; however the control defects had the greatest amount of new bone. Bone wax filled defects showed very little bone formation. The two-way ANOVA for MCT results showed significant differences for BV and BD between the different hemostatic agents during the two examination periods.

Conclusion:

Surgicel has superiority over bone wax in terms of osseous healing. Bone wax significantly hinders osteogenesis and induces inflammation.  相似文献   
66.
67.
Background:Isokinetic training (IKT) and core stabilization training (CST) are commonly used for balance training in musculoskeletal conditions. The knowledge about the effective implementation of these training protocols on radiological and biochemical effects in university football players with chronic low back pain (LBP) is lacking.Objective:To find and compare the effects of isokinetic training and CST on radiological and biochemical effects in university football players with chronic LBP.Design:Randomized, double-blinded controlled study.Setting:University hospital.Participants:60 LBP participants were randomized into isokinetic group (IKT; n = 20), core stabilization group (CST; n = 20) and the control group (n = 20) and received respective exercises for 4 weeks.Outcome measures:Radiological (muscle cross sectional area & muscle thickness) and biochemical (C-reactive protein, tumor necrosis factor -α, interleukin [IL]-2, IL-4, IL-6) values were measured at baseline and after 4 weeks (immediate effect).Results:The reports of the IKT, CST and control group were compared between the groups. Four weeks following training IKT group shows more significant changes in muscle cross sectional area (Psoas Major, Quadratus Lumborum, Multifidus and Erector Spinae muscles) and muscle thickness (Multifidus) than CST and control groups (p < 0.001). Biochemical measures such as C-reactive protein, tumor necrosis factor -α, IL-2, IL-4 and IL-6 also show significant improvement in IKT group than the other 2 groups (P < .001).Conclusion:Training through Isokinetic is an effective treatment program than conventional exercise programs in the aspect of radiological and biochemical analysis in university football players with chronic LBP, which may also help to prevent further injury. The present study can be used to improve the physical therapist''s knowledge and clinical decision skills on LBP in football players.  相似文献   
68.
Clinical Rheumatology - Diabetic neuropathy (DN) is a common and serious complication of diabetes. DN patients are suffering from anxiety, depression, and impairment of functional capacity. Rare...  相似文献   
69.

BACKGROUND

Malignant fibrous histiocytoma, a subtype of primary lung sarcoma is a very rare disease. It usually presents as a lung nodules and the final diagnosis is made by immunohistochemical studies.

METHODS

A 45-year-old patient presented with progressive dyspnea, dry cough and right shoulder pain. Chest X-ray revealed complete opacification of the right hemithorax. Chest computed tomography confirmed the presence of a heterogeneous lesion occupying the whole right hemithorax causing a mass effect on the trachea. Ultrasound guided biopsy was done and final pathology was suggestive of malignant fibrous histiocytoma.

CONCLUSION

Progressive dyspnea in young otherwise healthy patients should be investigated early on. In our case the presence of right shoulder pain indicates advance disease illustrated by the singular imaging findings.  相似文献   
70.
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