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Clinical Oral Investigations - The aim of this study was to investigate the effects of collagen cross-linking agents on nanomechanical and bonding properties of eroded dentin (ED), 24 h...  相似文献   
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Introduction

Left atrioventricular valve regurgitation is the most concerning residual lesion after surgical correction of atrioventricular septal defect.

Objective

To determine factors associated with moderate or greater left atrioventricular valve regurgitation within 30 days of surgical repair of incomplete atrioventricular septal defect.

Methods

We assessed the results of 51 consecutive patients 14 years-old and younger presenting with incomplete atrioventricular septal defect that were operated on at our practice between 2002 and 2010. The following variables were considered: age, weight, absence of Down syndrome, grade of preoperative left atrioventricular valve regurgitation, abnormalities on the left atrioventricular valve and the use of annuloplasty. The median age was 4.1 years; the median weight was 13.4 Kg; 37.2% had Down syndrome. At the time of preoperative evaluation, there were 23 cases with moderate or greater left atrioventricular valve regurgitation (45.1%). Abnormalities on the left atrioventricular valve were found in 17.6%; annuloplasty was performed in 21.6%.

Results

At the time of postoperative evaluation, there were 12 cases with moderate or greater left atrioventricular valve regurgitation (23.5%). The variation between pre- and postoperative grades of left atrioventricular valve regurgitation of patients with atrioventricular valve malformation did not reach significance (P=0.26), unlike patients without such abnormalities (P=0.016). During univariate analysis, only absence of Down syndrome was statistically significant (P=0.02). However, after a multivariate analysis, none of the factors reached significance.

Conclusion

None of the factors studied was determinant of a moderate or greater left atrioventricular valve regurgitation within the first 30 days of repair of incomplete atrioventricular septal defect in the sample. Patients without abnormalities on the left atrioventricular valve benefit more of the operation.  相似文献   
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The interest in non-invasive brain stimulation techniques is increasing in recent years. Among these techniques, transcranial direct current stimulation (tDCS) has been the subject of great interest among researchers because of its easiness to use, low cost, benign profile of side effects and encouraging results of research in the field. This interest has generated several studies and randomized clinical trials, particularly in psychiatry. In this review, we provide a summary of the development of the technique and its mechanism of action as well as a review of the methodological aspects of randomized clinical trials in psychiatry, including studies in affective disorders, schizophrenia, obsessive compulsive disorder, child psychiatry and substance use disorder. Finally, we provide an overview of tDCS use in cognitive enhancement as well as a discussion regarding its clinical use and regulatory and ethical issues. Although many promising results regarding tDCS efficacy were described, the total number of studies is still low, highlighting the need of further studies aiming to replicate these findings in larger samples as to provide a definite picture regarding tDCS efficacy in psychiatry.  相似文献   
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We made a retrospective longitudinal study from January 2000 to January 2003 to examine cases of immune reconstitution syndrome (IRS) and its incidence rate in tuberculosis (TB)-human immunodeficiency virus (HIV) co-infected patients. The incidence rate (IR) was calculated using a Poisson regression. The confidence interval (CI) that was stipulated was 95%. IRS occurred in 10/84 HIV and TB-positive patients; nine of them were on highly active anti-retroviral therapy (HAART) during a mean of 61.7 (+/- 59) days following the introduction of antiretrovirals. Lymph-node enlargement was the sole clinical manifestation. CD4 counts were <100 cells/mm(3)in 50% of the patients, at the time of TB diagnosis. All but two patients were treated with prednisone, and recovered from TB within a mean of 91 days (+/- 30 days). One relapse of TB was observed, but there were no IRS-related deaths. The incidence rate was higher (IR=11.18; CI, 1.41-88.76) in patients that had superficial lymph node enlargement at the moment of TB diagnosis (not associated with TB), extrapulmonary TB (IR=1.97; CI, 0.44-8.79), were antiretroviral naive (IR=1.85; CI, 0.48-7.16), and CD4 counts <100 cells/mm(3) (IR=1.50; CI, 0.40-5.59), although with a wide CI. IRS was frequent in our sample, occurred more frequently in HIV-naive patients with lymph-node enlargement and extrapulmonary TB. No cases of new pulmonary lesions or worsening of pulmonary infiltrates were observed.  相似文献   
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The aim of this study was to identify and characterize pituitary cells of Steindachneridion parahybae females in captivity, highlighting the possible relationship with reproductive disorders at this level, since this species shows oocyte final maturation, ovulation and spawning dysfunction in captivity. The localization and distribution of growth hormone (GH), prolactin (PRL), somatolactin (SL), β‐luteinizing hormone (β‐LH), and β‐follicle stimulating hormone (β‐FSH) immunoreactive (‐ir) cells in the adenohypophysis was studied by immunohistochemical and Western blot methods. In addition, cellular morphometric analyses and semi‐quantification of ir‐cells optical density (OD) during the annual reproductive cycle and after artificial induced spawning (AIS) were performed. Results showed that the distribution and general localization of pituitary cell types were similar to that of other teleost species. However, the morphometrical study of adenohypophysial cells showed differences along the reproductive cycle and following AIS. In general, females at the vitellogenic stage presented greater OD values for GH, PRL and SL than at other maturation stages (previtellogenic and regression stages), probably indicating an increased cellular activity during this stage. Conversely, β‐LH OD did not vary during the annual reproductive cycle. After AIS, β‐LH, SL and GH ir‐cells showed an increase in OD values suggesting a possible involvement on oocyte final maturation, ovulation and spawning or a feedback control on the brain‐pituitary‐gonads axis. Reproductive dysfunction in S. parahybae females in captivity may be due to alteration of the synthesis pathways of β‐LH. In addition, GH family of hormones could modulate associated mechanisms that influence the reproductive status in this species. Anat Rec, 298:1644–1658, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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