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This aim of this study was to determine the effect of anaesthetic agents on stapedius reflex (SR) thresholds and transient evoked otoacoustic emissions (TEOAE). Fifty patients who were scheduled for operation and who had normal hearing were included in the study. All were given midazolam for premedication and propofol for induction. Anaesthesia was maintained in five different ways in each group of 10 patients. Groups I-IV received inhalational anaesthesia: group I received 70 per cent N2O plus 30 per cent O2, group II sevoflurane, group III desflurane and group IV halothane. Group V received total intravenous anaesthesia with propofol plus sufentanil. The SR and TEOAE of the patients were measured four times: on the day before surgery (first measurement), after premedication (second measurement), after induction of anaesthesia (third measurement) and during maintenance of anaesthesia (fourth measurement). Midazolam significantly increased ipsilateral and contralateral SR thresholds and decreased TEOAE wave reproducibility. Propofol significantly increased only the SR thresholds. The other anaesthetic agents significantly increased only the contralateral reflex thresholds. Of these, the highest increase was seen after sevoflurane and the lowest after halothane. The changes in TEOAE wave reproducibility due to anaesthetic agents used for maintenance were not significant. We concluded that midazolam premedication may affect audiological evaluation with SR and TEOAE tests, and sevoflurane should not be used when it is necessary to measure SR under general anaesthesia.  相似文献   
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Background

Standard radiographs are limited in the evaluation of fracture characteristics and preoperative planning of OTA/AO 43C3 fractures. Therefore, CT imaging is an accepted as a useful method. CT is however expensive and has high radiation, and traction radiographs could be an alternative. This study aimed to compare fracture fragment and comminution zone visualization between traction radiographs and CT and any potentially resulting differences in consecutive treatment and surgical approach recommendations.

Methods

Twenty orthopaedic surgeons assessed traction radiographs and CT images of 12 OTA/AO 43C3 type fractures. Each observer was required to identify the anterolateral, posterolateral, and medial malleolus fragments and the lateral, central, and medial shoulder comminution zones. They then had to recommend treatment (nonoperative, ORIF, closed reduction and external fixation, percutaneous screw fixation, or primary tibiotalar arthrodesis) with the best surgical approach (medial, anterolateral, posterolateral, posteromedial, or combined). Intra- and interobserver reliability, correct identification of fracture fragments and comminution zones on both images, and consistency of treatment recommendations and surgical approaches were analyzed.

Results

The agreement of each observer’s assessment of the presence or absence of specific fracture fragments and comminution zones was substantially increased for CT as compared to traction radiographs, particularly for the posterolateral (p?=?0.000) and anterolateral fragment (p?=?0.000), and the lateral (p?=?0.000), central (p?=?0.000), and medial shoulder comminution zone (p?=?0.000). The interobserver reliability when assessing the three fracture fragments and comminution zones on the traction radiographs was moderate, whereas it was substantial when assessing these characteristics on CT. The medial malleolus fragment was more often correctly identified on traction radiographs than CT images (p?=?0.001). The ability to correctly identify lateral, central, and medial shoulder comminution zones was higher for CT than traction radiographs (p?=?0.000). The treatment and surgical approach recommendations after traction radiograph and CT evaluation were similar (p?<?0.05).

Conclusions

Traction radiographs may be a useful alternative to CT imaging in the preoperative planning of pilon fracture repair. Despite less reliable fracture fragment and comminution zone identification on traction radiographs, treatment recommendations and surgical approach were not influenced.  相似文献   
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Background: It is well known that arterial stiffness is associated with hypertension. Recent studies have shown that adiponectin +276 G/T, ACE I/D, AGTR1 A1166C, and eNOS E298D polymorphisms are likely to be risk factors for arterial stiffness. In this study, we aimed to investigate possible associations between these single-nucleotide polymorphisms (SNPs) and essential hypertension in a Turkish population. Methods: The study population consisted of 170 patients who were diagnosed with essential hypertension and 170 sex- and age-matched controls. Genotyping of adiponectin +276 G/T, ACE I/D, AGTR1 A1166C, and eNOS E298D SNPs were performed using real-time polymerase chain reaction and commercially produced kits. Results: The percentage of the adiponectin +276 T allele carriers was significantly higher in the patients with hypertension (33%) than in the controls (25%, p < 0.011). Through multiple logistic regression analysis, the adiponectin +276 T allele carrier was found to be associated with an increased risk of hypertension (TT vs. GG and TG: odds ratio = 3.318, p = 0.014, 95% confidence interval: 1.269–8.678). The genotype distributions or allelic frequencies of ACE I/D, AGTR1 A1166C, and eNOS E298D SNPs did not significantly differ between the patients with hypertension and the controls. Conclusion: The present study demonstrated that the adiponectin +276 G/T SNP is likely to be a risk factor for essential hypertension in a Turkish population.  相似文献   
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Oxidative stress may play an important role in the pathogenesis of psoriasis. Glutathione S‐transferases (GSTs) make up a group of antioxidant enzymes. Cytochrome p450 (CYP) enzymes can influence oxidation and reduction reactions. We investigated the potential effects of GST and CYP enzymes in the pathogenesis of psoriasis. The study included 32 psoriasis patients and 22 healthy subjects. Psoriasis patients were administered 20 sessions of narrowband ultraviolet B phototherapy. Expressions of GST and CYP enzymes were assessed by immunohistochemical staining. Expression levels of GSTK1, GSTM1, and GSTT1 were significantly higher in psoriasis than in control tissues (P = 0.022, P = 0.001, and P = 0.006, respectively). Pre‐ and post‐treatment expression was similar. Expression of CYP1A1 and CYP2E1 was significantly higher in pre‐ (P = 0.003 and P = 0.001, respectively) and post‐treatment (P = 0.003 and P = 0.001, respectively) psoriatic tissues than in control tissues. No significant differences in CYP1B1 levels between the study and control groups were detected before treatment (P > 0.05). However, CYP1B1 levels were higher in post‐treatment psoriatic tissue than in control tissue (P = 0.045). The significant increases in expression of GSTK1, GSTM1, and GSTT1 in psoriasis may reflect the increased activation of GST in response to excessive free radical formation from activated neutrophils or ultraviolet exposure to maintain antioxidant capacity in psoriasis. Furthermore, expressions of CYP1A1 and CYP2E1 represent important enzymatic systems in psoriasis. These findings suggest that psoriasis is an oxidative stress condition, although phototherapy does not affect these enzymatic systems. Further investigation is required.  相似文献   
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