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71.
BACKGROUND: Clinical studies suggest low-dose ketamine may have preemptive effects on postoperative pain in adults. The objective of this study was to determine whether intraoperative low-dose S-ketamine reduces postoperative pain and morphine consumption in children undergoing major urological surgery. MATERIALS: Thirty children scheduled for major urological surgery were included in this prospective study. Anesthesia was performed as total intravenous anesthesia (TIVA) with alfentanil and propofol. Fifteen patients additionally received an intravenous bolus of S-ketamine (0.2 mg.kg-1) followed by a continuous infusion of 5 microg.kg-1.min-1, which was stopped immediately after skin closure (Ketamine Group). Another 15 patients received an infusion of saline (Control group). After transfer to the PACU, pain intensity was evaluated using a numeric rating scale (NRS). First patient controlled analgesia (PCA) request, cumulative morphine consumption and pain intensities within the first 72 h were compared. RESULTS: Morphine consumption was not significantly different during the first 72 h (Control: 0.4 mg.kg-1, 0.24-0.51 mg.kg-1, Ketamine: 0.32 mg.kg-1, 0.19-0.61 mg.kg-1; median, 25-75% percentile; n.s.). However, differences were found in pain intensity during the first postoperative hour (Control: 4.0, 3.2-4.6, Ketamine: 2.5, 1.3-3.5; median, 25-75% percentile; P<0.05) and in the time to first PCA use (Control: 37, 28-46 min, Ketamine: 62, 38-68 min; median, 25-75% percentile; P<0.05). CONCLUSIONS: Intraoperative low-dose S-ketamine had no effect on morphine consumption during the first 72 h after surgery. The differences in pain intensity and time to first PCA use probably reflect additional sedation and antinociceptive effects of S-ketamine rather than a true 'prevention' of pain.  相似文献   
72.
ObjectiveBisphosphonate-related osteonecrosis of the jaw (BRONJ) is a serious side-effect of bisphosphonate therapy. In the majority of cases BRONJ occurs in the mandible. As a consequence a detailed investigation of BRONJ of the maxilla and in particular of involvement of the maxillary sinus has largely so far been neglected. The aim of this study was to analyse the frequency of maxillary sinusitis and oro-antral fistulae in BRONJ of the maxilla.Subjects and methodsA retrospective multicentre analysis was carried out in three Departments of Oral and Maxillofacial Surgery focussing on patients suffering from BRONJ in the maxilla. The role of involvement of the maxillary sinus, in particular sinusitis and oro-antral fistula, was analysed.ResultsOut of a total of 170 patients suffering from BRONJ 53 cases (31.2%) with involvement of the maxilla were identified. At least one sign of maxillary sinusitis was present in 43.6% (23/53) and an oro-antral fistula in the course of the disease was detected in 35.8% (19/53) of those patients. The mean length of time of bisphosphonate intake was 36.16 ± 16.32 months. Zoledronate was most frequently associated (60.4%) with symptoms, followed by the combination of Zoledronate/Ibandronate (13.2%), and Zoledronate/Pamidronate or Pamidronate alone (both 7.5%).ConclusionMaxillary sinusitis and oro-antral fistulae are associated with a BRONJ manifestation in the upper jaw in approximately 44%. The involvement of the maxillary sinus should be given special attention and three-dimensional imaging modalities might be necessary, not only to evaluate the extent of necrosis, but also to exclude involvement of the maxillary sinus.  相似文献   
73.
PURPOSE: To compare the measures of corneal thickness measurements obtained by an optical scanning slit method with those obtained by an ultrasound (US) pachometer, with special interest in the mid-peripheral (2.5 mm from centre) and peripheral (4.5 mm from centre) region of the cornea. METHODS: Three measures of corneal thickness were taken using Orbscan II and then by US pachometry (under topical anaesthesia with benoxinate 0.4%) on 24 adults, aged 20-58 years and with up to 8.5 D of myopia. The full Orbscan topography maps were used to extract single point data along the horizontal corneal meridian for the geometric centre, 2.5 mm from centre (nasal and temporal) and 4.5 mm (nasal and temporal) from centre. No correction factor was used for the Orbscan data. The same set of measures were made with the US pachometer. In all cases, the averages of three (centre) or six (mid-periphery and periphery) readings were taken as the measurements from each cornea. RESULTS: Orbscan readings on the right eyes averaged 0.576, 0.632 and 0.712 mm for central, mid-peripheral and peripheral sites with average values for emmetropic subjects (<1 DS, n = 12) being marginally higher than for myopic subjects (average - 4.00 DS, n = 12). For US pachometry, the average values were however 0.522, 0.554 and 0.606 mm. Similar results were obtained on left eyes. Combining data from both eyes also showed that the mean difference between Orbscan II and US measures was not constant across the cornea, being 0.055 +/- 0.014 mm at the centre, 0.080 +/- 0.019 mm at mid-peripheral locations and 0.107 +/- 0.046 mm at the peripheral sites. These differences persisted after application of the generally recommended acoustic factor (x0.92) to all of the Orbscan readings. CONCLUSIONS: A single acoustic factor correction cannot be applied to all corneal thickness measures made with an Orbscan II to equate the measures to those made with an US pachometer.  相似文献   
74.
BACKGROUND: In malignant melanoma, recent studies have demonstrated an important role of matrix-metalloproteinase 2 (MMP-2), its co-activating enzyme membrane-type matrix-metalloproteinase 1 (MT1-MMP), and the endogenous inhibitor of MMP-2, tissue-inhibitor of matrix metalloproteinase 2 (TIMP-2). Melanocytic nevi are benign neoplasms of the melanocytic lineage, but may exhibit dysplastic features that can be difficult to distinguish from early stage melanoma. As shown in earlier studies, nevi show important morphological and phenotypical changes in response to ultraviolet light (UVB) irradiation. OBJECTIVE: To clarify the role of MMP-2, TIMP-2 and MT1-MMP in UVB-irradiated vs. non-irradiated melanocytic nevi. METHODS: Immunohistochemical comparison of the MMP-2, TIMP-2 and MT1-MMP expression pattern. RESULTS: MMP-2 is expressed by lesional keratinocytes and its expression is up-regulated by UVB-irradiation. MMP-2 expression was not observed in melanocytic cells. TIMP-2, by contrast, is predominantly expressed by melanocytic nevus cells, and its expression is in part down-regulated by UVB-irradiation. MT1-MMP is expressed by basal keratinocytes and to a weaker extent by melanocytic nevus cells. CONCLUSIONS: MMP-2 expression by keratinocytes in nevi probably represents the result of activation of keratinocyte turnover in lesional epidermis. MMP-2 could play a role in the downward movement of junctional nevus cells into the dermis. The reduction of TIMP-2 expression in melanocytic cells by UV-light together with the enhanced expression of MMP-2 in the adjacent epidermis may promote basement membrane degradation. The expression pattern of MT1-MMP in close proximity to epithelial-mesenchymal interfaces underlines the synergistic role of MT1-MMP in this process.  相似文献   
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77.
The 23S rRNA A2058G alteration mediates macrolide, lincosamide, and streptogramin B resistance in the bacterial domain and determines the selectivity of macrolide antibiotics for eubacterial ribosomes, as opposed to eukaryotic ribosomes. However, this mutation is associated with a disparate resistance phenotype: It confers high-level resistance to ketolides in mycobacteria but only marginally affects ketolide susceptibility in streptococci. We used site-directed mutagenesis of nucleotides within domain V of 23S rRNA to study the molecular basis for this disparity. We show that mutational alteration of the polymorphic 2057-2611 base pair from A-U to G-C in isogenic mutants of Mycobacterium smegmatis significantly affects susceptibility to ketolides but does not influence susceptibility to other macrolide antibiotics. In addition, we provide evidence that the 2057-2611 polymorphism determines the fitness cost of the 23S rRNA A2058G resistance mutation. Supported by structural analysis, our results indicate that polymorphic nucleotides mediate the disparate phenotype of genotypically identical resistance mutations and provide an explanation for the large species differences in the epidemiology of defined drug resistance mutations.  相似文献   
78.
Surgery for fulminating colitis during pregnancy   总被引:2,自引:1,他引:2  
Two cases of fulminating colitis presenting during pregnancy are described. In both cases, resectional surgery was performed. In the first case, cesarean section was combined with subtotal colectomy and ileostomy during the 32nd week of gestation. In the second case, cesarean section was performed during the 33rd week of gestation and proctocolectomy in the puerperium. In both cases, histopathologic examination showed colitis more consistent with Crohn's disease. It is concluded that if fulminating colitis appears during pregnancy it should be treated in the same manner as in the nonpregnant state.  相似文献   
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80.

Background

The right ventricular ejection fraction (RVEF) is a surrogate marker of right ventricular function in pulmonary hypertension (PH), but its measurement is complicated and time consuming. The tricuspid annular plane systolic excursion (TAPSE) measures only the longitudinal component of RV contraction while the right ventricular fractional area change (RVFAC) takes into account both the longitudinal and the transversal components. The aim of our study was to evaluate the relationship between RVEF, RVFAC, and TAPSE according to hemodynamic severity in two groups of patients with PH: pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH).

Methods and Results

Fifty-four patients with PAH (n?=?15) and CTEPH (n?=?39) underwent right heart catheterization and cardiac magnetic resonance (CMR). The ventricular volumes and areas, TAPSE, and eccentricity index were measured. The RVFAC was more strongly correlated with the RVEF (r?=?0.81, p?<?0.0001) than the TAPSE (r?=?0.63, p?<?0.0001). RVEF?<?35% was better predicted by the RVFAC than the TAPSE (TAPSE: AUC?=?0.77 and RVFAC: AUC?=?0.91; p?=?0.042). In the group with the worse hemodynamic status, the RVFAC correlated much better with the RVEF than the TAPSE. There were no significant differences in the CMR data analyzed between the groups of PAH and CETPH patients.

Conclusions

The RVFAC is a good index to estimate RVEF in PH patients; even better than the TAPSE in patients with more severe hemodynamic profile, possibly for including the transversal component of right ventricular function in its measurement. Furthermore, RVFAC performance was similar in the two PH groups (PAH and CTEPH).
  相似文献   
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