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991.
Myocardial velocities have prognostic implications, and transmitral E wave to mitral annular early diastolic tissue velocity ratio (E/Em) is utilized to estimate left ventricular (LV) end-diastolic pressure (EDP). There are no reference values for 2-dimensional (2D) speckle tracking myocardial velocities (S(2D), E(2D), A(2D)), and it is unknown if they are comparable with color tissue Doppler imaging (TDI). Predictors of E/E(2D) ratios are unknown and E/E(2D) has not been validated with LVEDP. The myocardial velocities of 142 subjects were measured by TDI and 2D speckle tracking. Mean E/Em and E/E(2D) were calculated as transmitral E wave to mean 6 basal early diastolic myocardial velocities using TDI and 2D speckle tracking respectively, and compared with LVEDP during catheterizations (n = 20). Mean E(2D) was lower but mean S(2D) and A(2D) were higher than TDI (all p <0.001). When TDI sample volume was tracked throughout the cardiac cycle, this directional difference was no longer apparent with S(2D), E(2D), and A(2D) higher than TDI (all p <0.05). Age, systolic blood pressure, LV ejection fraction, and mean S(2D) were independent correlates of E/E(2D). Receiver-operator characteristic analysis showed E/E(2D) (p = 0.03), not E/Em, identified elevated LVEDP (>/=12 mm Hg). E/E(2D) of 11.6 had 83% sensitivity and 70% specificity to predict elevated LVEDP. In conclusion, TDI and 2D speckle tracking myocardial velocities are not comparable due to angle independency and ability for tissue tracking with the latter. LV systolic function, age, and afterload are independent correlates of E/E(2D). Only E/E(2D) identifies elevated LVEDP, and an E/E(2D) of 11.6 has the optimal sensitivity and specificity.  相似文献   
992.
Chemical insecticides have been widely used in Brazil for several years. This exposes mosquito populations to an intense selection pressure for resistance to insecticides. In 1999, the Brazilian National Health Foundation started the first program designed to monitor the resistance of Aedes aegypti to insecticides. We analyzed populations from 10 municipalities (from 84 selected in Brazil) in the states of Rio de Janeiro and Espírito Santo. Exposure of larvae to a diagnostic dose of temephos showed in alterations in susceptibility in all populations. Mosquitoes from eight municipalities exhibited resistance, with mortality levels ranging from 74% (Campos dos Goytacazes, Rio de Janeiro) to 23.5% (S?o Gon?alo, Rio de Janeiro). The resistance ratios of mosquitoes from three municipalities ranged from 3.59 to 12.41. Adults from only one municipality (Nova Igua?u, Rio de Janeiro) remained susceptible to both fenitrothion and malathion. These results are being used to define new local vector control strategies.  相似文献   
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The current study aimed to investigate the midterm (24 hour) response of 17-hydroxyprogesterone (17-OHP) and dehydroepiandrosterone sulphate (DHEA-S) to synthetic high-dose adrenocorticotropin (ACTH) in adrenal incidentalomas (Al). Seventeen patients with Al and 40 age- and sex-matched controls received synthetic ACTH (tetracosactide, 1000 microg, IM). Plasma, 17-OHP and DHEA-S were collected in basal conditions and after 1, 4, 6, 8 and 24 hours. (HPA) axis was also evaluated using circadian serum cortisol, urinary free cortisol and over-night 2 mg dexamethasone suppression. Basal plasma 17-OHP levels did not differ among the groups. However, the increment in plasma 17-OHP in patients both in terms of peak [13.76 +/- 2.52, 4.77 +/- 0.30ng/ml, mean +/- S.E.M, p < 0.001] and area under the curve [190 +/- 46, 96.75 +/- 32 ng/ml/h, p < 0.001] were significantly higher than that of the controls. Stimulated 17OH-P levels never reached 9.1 ng/ml in controls. Sixty-five (11/17) % of the patients were found to have exaggerated response. Three of the patients were found to have subclinical Cushing's syndrome and interestingly, two augmented their 17-OHP response to ACTH after unilateral adrenalectomy and normalisation of their HPA axis. Basal DHEA-S levels of the patients were significantly lower [99.21 +/- 45, 230.18 +/- 34 microg/dl, p < 0.01] and stayed persistently lower than that of the controls. Evidence of a heterozygous 21 hydroxylase deficiency, as indicated by the exaggerated 17-OHP response to ACTH, has been widely reported in Al patients. However, to our knowledge to date there is no report on augmented 17-OHP response to ACTH after adrenalectomy. Possible reasons for the augmentation were discussed.  相似文献   
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AIMS: Ablation of the atrial isthmus between the tricuspid annulus and the inferior vena cava changes P-wave morphology during low lateral right atrial pacing. For better understanding of the mechanism of this alteration, the sequence of activation of the inter-atrial septum and the left atrium were compared before and after ablation of the isthmus between the inferior vena cava and the tricuspid annulus. METHODS AND RESULTS: In 13 patients, left atrial mapping was performed using a duodecapolar electrode catheter advanced to the far distal coronary sinus. The inter-atrial septum was mapped using a right atrial duodecapolar electrode catheter. Conduction times were measured during low lateral right atrial pacing from the pacing artefact and during sinus rhythm from the earliest right atrial electrogram to every intra-cardiac electrogram before and after the ablation. During low lateral right atrial pacing, isthmus ablation resulted in a significant delay in every left atrial lead. Changes were maximal at the posterior aspect of the left atrium and minimal at its anterior aspect. No significant change was discernible on the inter-atrial septum. During sinus rhythm, atrial activations remained unchanged. CONCLUSION: Electrocardiographic changes of P-wave morphology result from alteration in the sequence of left atrial activation rather than that of the inter-atrial septum.  相似文献   
995.
Background: Patients with diabetes mellitus who undergo coronary stenting are at increased risk of restenosis. It is known that inflammation plays a crucial role in restenosis. Objective: We assessed the inflammatory response to elective coronary stent implantation (CSI) in stable diabetic and nondiabetic patients. Methods: C‐reactive protein (CRP), soluble (s) P‐selectin, and soluble intercellular adhesion molecule (sICAM)‐1 plasma levels were determined in diabetic (n = 51) and nondiabetic (n = 56) patients before and 48 hours and 4 weeks after bare metal stenting (BMS). Results: Diabetic patients presented significantly higher inflammatory marker levels before and after CSI. Nonetheless, diabetic and nondiabetic patients had postintervention peak of markers attained within 48 hours. At baseline, diabetic and nondiabetic patients presented CRP levels of 5.0 ± 20.1 (P ≤ 0.04) and 3.8 ± 9.4 μg/ml and, at 48 hours postintervention, 22.0 ± 20.2 (P = 0.001; P = 0.002) and 12.6 ± 11.3 (P ≤ 0.0001) μg/ml. Regarding sP‐selectin, diabetic and nondiabetic patients obtained levels of, at baseline, 182 ± 118 (P ≤ 0.04) and 105 ± 48 ng/ml and, at 48 hours, 455 ± 290 (P = 0.001; P ≤ 0.01) and 215 ± 120 (P ≤ 0.04) ng/ml. For diabetic and nondiabetic patients, sICAM‐1 levels were, at baseline, 248 ± 98 (P ≤ 0.04) and 199 ± 94 ng/ml and, at 48 hours, 601 ± 201 (P = 0.001; P ≤ 0.01) and 283 ± 220 (P = 0.001) ng/ml. At 4 weeks, for all patients, markers returned to preprocedural levels: versus before PCI: *P = 0.001, §P ≤ 0.0001; versus nondiabetic patients: #P ≤ 0.04, P = 0.002, ?P ≤ 0.01. Conclusions: Diabetic and nondiabetic patients exhibited a temporal inflammatory response after an elective BMS. However, diabetic patients present higher preprocedural levels of CRP, sP‐selectin, and sICAM‐1 and reveal a further exacerbated inflammatory response after intervention. The differences in inflammatory response may have implications in restenosis within these two sets of patients.  相似文献   
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Objectives

The objective of the present study was to evaluate the influence of proximal box elevation on microtensile bond strength (mTBS) of composite inlays to the proximal box floor, using either a total-etch or a self-adhesive resin cement.

Materials and methods

Twenty-five human molars were selected, and a class II OM (inlay) cavity preparation was performed in each tooth. Cavities were randomly assigned into four experimental groups, according to the location of the proximal cervical margin (located 1 mm below cementoenamel junction (CEJ), or with proximal box elevation with composite resin) and the resin cement used for luting (a total-etch resin cement RelyX ARC or a self-adhesive resin cement G-Cem). After 1-week water storage, samples were subjected to mTBS test. Results were analyzed by Kruskal–Wallis and Mann–Whitney U tests (p < 0.05).

Results

Kruskal–Wallis revealed statistically significant differences among experimental groups (p = 0.007). Both resin cements showed similar bond strength values when cervical margin was located below CEJ. The proximal box elevation improved the bond strength of composite inlays for both resin cements. However, only for G-Cem was this improvement statistically significant.

Conclusions

The proximal box elevation improved the bond strength attained by G-Cem resin cement. For RelyX ARC, the position of the cervical margin did not affect composite inlays bond strength.

Clinical relevance

Proximal box elevation does not decline bond strength of composite inlays to the proximal floor when a total-etch or a self-adhesive resin cement is used.

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