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101.
102.
We evaluated changes in serum zinc (Zn) and copper (Cu) levels in two groups of children with chronic renal failure (CRF) – children with CRF who were on regular hemodialysis (Group 1, n=40) and children with CRF who were on conservative management (Group 2, n=31) – and in one group of healthy children (Group 3, n=30). All of the participants in the study were between 5–18 years old, and the composition of the three groups was almost identical with respect to age and sex. The length of time the children in Group 1 had been on hemodialysis varied between 3 and 52 months (mean: 20.97±14.8 months). To evaluate the impact of the duration of dialysis on serum levels of Zn, we further sub-divided Group 1 patients into two subgroups: Subgroup A patients (n=20) had been on hemodialysis therapy for less than 18 months (mean: 8.85±4.83 months); Subgroup B patients (n=20) had been on hemodialysis therapy for longer than 18 months (mean: 33.1±10.86 months). The PIXE (proton-induced X-ray emission) was used for measuring the trace elements. Results: The mean serum level of Zn was lower in the Group 1 (hemodialysis group) children than in the children of Group 2 (on conservative management) and group 3 (healthy children) (p<0.001), but the difference was not significant between Groups 2 and 3. No significant differences in serum levels of Cu were found among the three groups. The serum level of Zn was lower in Subgroup B than in Subgroup A (p<0.001). The correlation test showed that there was an inverse linear relation between the length of time the child was on the hemodialysis regimen and serum Zn levels. Conclusion: Chronic hemodialysis may lead to abnormalities in the serum levels of some trace elements in children with CRF that increase in severity with increasing duration of hemodialysis. Deficiencies of these trace elements – zinc in particular – may contribute to various conditions and symptoms in children undergoing chronic hemodialysis.  相似文献   
103.
Chan VW  Nova H  Abbas S  McCartney CJ  Perlas A  Xu DQ 《Anesthesiology》2006,104(2):309-14, discussion 5A
BACKGROUND: Few studies have examined the use of ultrasound for sciatic nerve localization. The authors evaluated the usefulness of low-frequency ultrasound in identifying the sciatic nerve at three locations in the lower extremity and in guiding needle advancement to target before nerve stimulation. METHODS: In this prospective observational study, 15 volunteers underwent sciatic nerve examination using a curved ultrasound probe in the range of 2-5 MHz and a Philips-ATL 5000 unit (ATL Ultrasound, Bothell, WA) in the gluteal, infragluteal, and proximal thigh regions. Thereafter, an insulated block needle was advanced inline with the ultrasound beam to reach the nerve target, which was further confirmed by electrical stimulation. The quality of sciatic nerve images, ease of needle to nerve contact, threshold stimulating current, and resultant motor response were recorded. RESULTS: The sciatic nerve was successfully identified in the transverse view as a solitary predominantly hyperechoic structure on ultrasound in all of the three regions examined. The target nerve was visualized easily in 87% and localized within two needle attempts in all patients. Nerve stimulation was successful in 100% after two attempts with a threshold current of 0.42 +/- 0.12 (mean +/- SD) eliciting foot plantarflexion or dorsiflexion. CONCLUSIONS: These preliminary data show that a curved 2- to 5-MHz ultrasound probe provides good quality sciatic nerve imaging in the gluteal, infragluteal, and proximal thigh locations. Ultrasound-assisted sciatic nerve localization is potentially valuable for clinical sciatic nerve blocks.  相似文献   
104.
105.
In this paper, the problem of persistent‐bounded disturbance rejection of linear continuous‐time systems with time‐varying delays is investigated using the tools of invariant set analysis and Lyapunov‐function methodology. We derive less conservative sufficient conditions on robust attractor for time‐delay systems in terms of strict linear matrix inequalities (LMIs) to guarantee the desired ??1‐performance. A robust output‐feedback controller is designed and the associated gain is determined using strict LMIs. The developed results are tested on two representative time‐delay examples. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
106.
Sadeghi M, Daniel V, Naujokat C, Schmidt J, Mehrabi A, Zeier M, Opelz G. Decreasing plasma soluble IL‐1 receptor antagonist and increasing monocyte activation early post‐transplant may be involved in pathogenesis of delayed graft function in renal transplant recipients
Clin Transplant 2010: 24: 415–423. © 2009 John Wiley & Sons A/S. Abstract: Delayed graft function (DGF) increases the risk of acute allograft rejection and may affect long‐term graft survival. We compared pre‐transplant, early post‐transplant, and late post‐transplant serum creatinine (Cr) and plasma levels of neopterin, cytokines, and cytokine receptors/antagonists in patients with DGF (n = 39), slow graft function (SGF) (n = 43), or immediate graft function (IGF) (n = 30). Three and eight days post‐transplant, plasma neopterin (p < 0.001; p < 0.001), Soluble Interleukin‐6 (IL‐6) receptor (R) (p = 0.002; p = 0.001), and IL‐10 (p = 0.003; p = 0.001) were higher in DGF than IGF patients. One month post‐transplant, plasma neopterin (p < 0.001) and IL‐10 (p < 0.001) were higher in DGF than IGF patients. Three days post‐transplant, the results indicated reduced sIL‐1 receptor antognist (RA) production in DGF patients (p = 0.001). Simultaneously, plasma sIL‐6R and IL‐10 increased in DGF (p < 0.001; p = 0.003) and SGF (p = 0.007; p = 0.030) patients, indicating increased production of sIL‐6R and IL‐10. Lower sIL‐1 production in DGF than IGF patients early post‐transplant might promote the increased production of monocyte‐derived neopterin, sIL‐6R, and IL‐10. This monocyte/macrophage activation might induce inflammation in the graft and subsequently cause an impairment of graft function. Blocking of monocyte activity after renal transplantation may be considered a potential approach for improving graft outcome.  相似文献   
107.
PurposeSurgical treatment in advanced-stage infantile Blount’s disease with medial plateau (MP) depression is challenging. Several osteotomies and fixation methods have been described with no established benchmark. We conducted this study to evaluate the efficacy and safety of a new single-stage technique for acute medial condyle elevation and metaphyseal osteotomies with internal fixation.MethodsA prospective case series of 19 consecutive patients (21 knees) with severe infantile Blount’s disease underwent a single-stage MP elevation and metaphyseal osteotomies, with internal fixation. The mean age was 10.3 years (8.2 to 13.6) and the mean follow-up was 5.1 years (3.2 to 8.3). The outcome measures included clinical and radiological parameters and patient-reported pediatric outcomes data collection instrument (PODCI) score.ResultsThe mean PODCI score improved significantly from 50% to 88%. The mean internal tibial torsion improved from -27° to 11°. All cases maintained full knee extension, no limitation in flexion range of movement and no signs of instability or lateral thrust gait. All the radiographic parameters improved significantly; the mean tibiofemoral angle improved from -29° to 7°, the metaphyseal-diaphyseal angle improved from 33.4° to 4.7° and the angle of depressed MP improved from 38.3° to 2.4° (p < 0.001). At the latest follow-up, no cases of deformity recurrence were identified, the final limb-length discrepancy was < 1 cm in all patients.ConclusionSingle-stage MP elevation and metaphyseal osteotomies with internal fixation significantly improved the clinical and radiographic parameters and PODCI score in advanced infantile Blount’s disease and precluded the use of external immobilization, with no evidence of deformity recurrence.Level of evidenceIV  相似文献   
108.
109.
Testicular torsion/detorsion is one of the important emergencies that requires fast surgical intervention. This study aimed to investigate the effects of Salvia miltiorrhiza hydroalcoholic extract combined with verapamil on testicular ischaemia/reperfusion damage in Wistar albino rats. All animals were distributed in 3 groups (n = 8), including the sham-operated group, torsion/detorsion (TD) group and torsion/detorsion + pretreatment with 200 mg/kg Salvia miltiorrhiza extract combined with 0.3 mg/kg verapamil (SMV) group. Oxidative stress biomarkers (MDA, GPx, CAT and TAC) both in plasma and testicular tissue, sperm parameters (motility, vitality, concentration and morphology) and histopathological parameters (MSTD, GECT, Johnson's score, Cosentino's score and testicular cell thickness) were assessed in all groups. Ischaemia/reperfusion significantly increased MDA and decreased GPx, CAT and TAC levels (p < .05). Pretreatment with SMV significantly increased GPx, CAT and TAC levels (p < .05). SMV group increased progressive sperm motility and vitality and reduced non-progressive motility of spermatozoon (p < .05). Testicular torsion significantly decreased all histopathological parameters compared to the sham group (p < .05). SMV pretreatment remarkably increased MSTD, GECT and Cosentino's score in comparison with the TD group (p < .05). A combination of Salvia miltiorrhiza with verapamil could reduce damages triggered by testicular torsion detorsion and improve sperm functionality parameters and oxidative stress defence systems.  相似文献   
110.
BACKGROUND AND OBJECTIVES: Glomangiomas are rare, vascular tumors consisting of an afferent artery, arteriovenous canal, neuro-reticular elements, collagen, and efferent veins, and are most often located in the soft tissue of the upper extremities. We describe how the use of ultrasound-guided nerve blockade altered the anesthetic management of a patient with multiple glomangiomatosis undergoing elective forearm surgery. ULTRASOUND FINDINGS: A 32-year-old man was scheduled for excision of painful glomangiomas from the ulnar aspect of his right wrist, with exploration of his ulnar nerve. The anesthetic concerns included (1) morbid obesity, (2) chronic pain syndrome and opioid intolerance, (3) a potentially difficult airway, and (4) obstructive sleep apnea. Ultrasound-guided supraclavicular blockade was the proposed anesthetic of choice. Ultrasound scan of the supraclavicular fossa revealed numerous vascular lesions surrounding the divisions of the brachial plexus. Color Doppler imaging confirmed these pulsatile lesions to be vascular in origin. Even under two-dimensional ultrasound guidance, we believed that the risk of vascular puncture and unintentional intravascular injection of local anesthetic was high, and therefore we abandoned the supraclavicular approach. A successful ultrasound-guided axillary brachial plexus blockade was performed uneventfully. CONCLUSIONS: Although multiple glomangiomatosis is a rare disease, this case illustrates the invaluable contribution that ultrasound has made to modern, regional anesthetic practice, especially for patients with aberrant anatomy in whom traditional nerve-localization techniques could result in serious complications.  相似文献   
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