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991.
Journal of Autism and Developmental Disorders - Oxidative stress has been proposed as being important in the pathophysiology of autism spectrum disorders (ASD), and heightened levels of oxidative...  相似文献   
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Previous experimental studies have demonstrated that aortic valve disease is associated with significant downstream turbulence (T). In this study, we developed a noninvasive method on the basis of Doppler velocity recording for quantitating aortic blood flow T in patients with aortic valve disease. The instantaneous blood velocity at a point in the aorta is equal to the sum of a mean periodic velocity component with a random or turbulent velocity component. According to the ensemble average method, time mean absolute T intensity is the root-mean-square value of turbulent velocity averaged over time and T is better quantitated by the relative T intensity (TIr), which is the ratio of absolute T intensity to the ensemble average velocity averaged over time. We computed TIr in 18 patients with mild to severe aortic stenosis and in 13 healthy volunteers from instantaneous modal velocities of 70 cycle length-matched heart beats recorded in the proximal part of the descending aorta by pulsed Doppler using an ultrasound system with an output port for online digital data transfer into a microcomputer. TIr was greater in patients with aortic valve disease (18.4 +/- 5.1%, range 11.2%-28.9%) than in control patients (7.9 +/- 1.9%, range 4.8%-9.8%; P =.0001). In patients with aortic valve disease, TIr was better linearly related to the ratio of postvalvular aorta to valvular orifice cross-sectional areas (r = 0.89, P =.0001) than to other parameters of valve restriction: transvalvular pressure gradient (r = 0.78, P =.0001); valve area (r = -0.56, P =.01); and valve resistance (r = 0.72, P =.0002). Thus, T that can be computed noninvasively from direct digital transfer of Doppler velocity data appears to be linearly related to indices of aortic valve restriction. Our data support the concept of the postvalvular aorta to valvular orifice cross-sectional areas ratio as a new important hemodynamic parameter in patients with aortic valve disease.  相似文献   
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Purpose: Implant infections are severe complications in orthopedic surgery. Treatment using antibiotics is often unsuccessful without removing the implant due to biofilm formation. In this context, antiseptics may be a potential option. These solutions have a wide antimicrobial spectrum but often cause damage to the local cell populations. In these cases, electrochemically activated solutions (ECAS) may be an alternative.

Methods: Staphylococcus aureus was cultured overnight on polyethylene platelets under different growing conditions (standard-/-different biofilm inducing conditions). The samples were treated with an ECAS (0%–30%) and analyzed with regard to their antimicrobial efficacy and their effect on biofilm structures by determining the living bacterial count and scanning electron microscopy.

Osteoblast and chondrocyte cell lines (MG-63, and CAL-78, respectively) were cultured to confluence and treated with an ECAS. Total cell count, metabolic activity using FDA staining, and proliferation using Ki67 staining were analyzed.

Results: ECAS showed antimicrobial activity in concentrations <1%. In cases of biofilm formation, bacterial toxicity could be detected at concentrations from 3.75 –7.5%. At these same concentrations, a visible change in biofilm structure was observed. Regarding biocompatibility rates, up to 7.5% (of osteoblasts) and 3.75% (of chondrocytes) had little influence on metabolic activity and proliferation.

Conclusion: ECAS provide good antimicrobial efficacy while maintaining high biocompatibility. These results suggest that these solutions may provide promising alternatives in the treatment of implant-associated infections.  相似文献   

997.

Purpose

Postoperative pain management for living liver donors has become a major concern as a result of the increasing number of living liver donations. Transversus abdominis plane (TAP) block has been known to provide effective analgesia for abdominal surgery. The aim of this study was to evaluate the efficacy of ultrasound-guided continuous subcostal TAP block as a part of a multimodal analgesic regimen in comparison with conventional intravenous (IV) fentanyl-based analgesia in living liver donors.

Methods

Thirty-two donors were retrospectively classified into either the continuous subcostal TAP block group (TAP group) or the IV fentanyl-based analgesia group (control group). TAP group donors received bilateral continuous subcostal TAP infusion of 0.125 % levobupivacaine at 6 ml/h. Control group donors did not receive any neural blockade.

Results

Cumulative fentanyl consumption was significantly lower in the TAP group for 48 h (P < 0.01) as compared to the control group. Further, the donors in the TAP group had significantly lower incidence of nausea and vomiting during 24–48 h postoperatively (P < 0.01) and fewer delays in the initiation of oral intake than those in the control group (P = 0.02).

Conclusions

In conclusion, continuous subcostal TAP block provided an effective opioid-sparing analgesia for living liver donors.
  相似文献   
998.

Background

The benefit of post-urinary tract infection (UTI) sonography to detect clinically significant renal abnormalities remains a subject open to debate. Decision curve analysis (DCA) is a novel method for evaluating the clinical usefulness of diagnostic tests. Our objective was to determine, using DCA, the benefit of post-UTI sonography and of post-UTI sonography with biological markers of inflammation to predict the risk of recurrence of febrile UTI in children aged 2 to 24 months without known uropathy.

Methods

We retrospectively analyzed all children aged 2 to 24 months, without known uropathy, who presented with a first episode of febrile UTI between 2009 and 2012 and followed them for 30 months. We then used DCA to estimate the benefit of post-UTI sonography or post-UTI sonography + biological markers of inflammation for detecting the risk of recurrence.

Results

A total of 318 children [144 boys (45.3 %) and 174 girls (54.7 %)], with a mean age of 6.9?±?5.6 months, were identified. Of these, 210 children presented with a significant inflammation [66.2 %; 95 % confidence interval (CI) 61.0–71.4], and 30 (9.4 %; 95 % CI 6.2–12.6) presented with abnormal post-UTI sonographic findings. Eighteen (5.7 %; 95 % CI 3.1–8.2) children presented with recurrent UTI at 30 months.

Conclusions

There were significantly more recurrences in those children who presented with abnormal sonographic findings than in those who did not (relative risk?7.68; 95 % CI 3.03–19.46). However, taking into account the effect of false-positives and false negatives, the DCA revealed that for threshold probabilities of >30 %, at which patients/doctors are concerned about unnecessary interventions (whether tests or treatments), neither post-UTI sonography nor post-UTI sonography + biological markers of inflammation have sufficient value to improve care.
  相似文献   
999.

Introduction and hypothesis

The aim of the study was to correlate histological and biomechanical characteristics of the vaginal wall in women with pelvic organ prolapse (POP).

Methods

Tissue samples were collected from the anterior [point Ba; POP Questionnaire (POP-Q)] and/or posterior (point Bp; POP-Q) vaginal wall of 15 women who underwent vaginal surgery for POP. Both histological and biomechanical assessments were performed from the same tissue samples in 14 of 15 patients. For histological assessment, the density of collagen and elastin fibers was determined by combining high-resolution virtual imaging and computer-assisted digital image analysis. For biomechanical testing, uniaxial tension tests were performed to evaluate vaginal tissue stiffness at low (C0) and high (C1) deformation rates.

Results

Biomechanical testing highlights the hyperelastic behavior of the vaginal wall. At low strains (C0), vaginal tissue appeared stiffer when elastin density was low. We found a statistically significant inverse relationship between C0 and the elastin/collagen ratio (p?=?0.048) in the lamina propria. However, at large strain levels (C1), no clear relationship was observed between elastin density or elastin/collagen ratio and stiffness, likely reflecting the large dispersion of the mechanical behavior of the tissue samples.

Conclusion

Histological and biomechanical properties of the vaginal wall vary from patient to patient. This study suggests that elastin density deserves consideration as a relevant factor of vaginal stiffness in women with POP.
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