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1.
The hypocretin/orexin (Hcrt/orexin) unit affects the functions of the nervous, cardiovascular, gastrointestinal, and reproductive systems. Hcrt/orexin ligands and receptors have been localized to different parts of the central and peripheral nervous systems, cerebrospinal fluid and blood, exocrine (pancreas, salivary, lacrimal) as well as endocrine (pancreatic islets, pituitary, adrenal) glands. Several factors including stress, glucagon‐like peptide‐1 agonists, glutamate, nicotine, glucose, and hypoglycaemia stimulate the expression of Hcrt/orexin system, but it is inhibited by ageing, bone morphogenetic protein, hypoxia/hypercapnia, melanocortin receptor accessory protein 2, and glucagon. Literature reports show that Hcrt/orexin can significantly increase insulin secretion from normal and diabetic rat pancreata. Hcrt/orexin decreases blood glucose concentration and reduces insulin resistance partly via increased tissue expression of glucose transporter type 4. It reduces obesity by increasing browning of fat cells and energy expenditure. Taken together, Hcrt/orexin modulates obesity and the metabolism of glucose and insulin. The Hcrt/orexin system may thus be a target in the development of new therapies for the treatment of diabetes mellitus.  相似文献   
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Background

Fractures of acrylic resin dentures are a common occurrence in clinical dentistry. The denture may be fractured accidentally when dropped or while in service in the mouth due to flexural fatigue.

Objectives

The aim of this study was to compare the elastic modulus and the flexural strength between two heat-cured acrylic resins used in denture bases: a high-impact resin (Lucitone 199) and a traditional resin (Rodex).

Materials and methods

Rectangular strips of Lucitone 199 and Rodex (10 samples each) were fabricated and stored in artificial saliva at 37 °C for 2 weeks. The specimens were subjected to a three-point flexural test. The data were statistically analysed with Student’s t-test (p ⩽ .05).

Results

The high-impact acrylic resin had a lower elastic modulus (p = .000) and higher flexural strength (p = .001) compared to the traditional acrylic resin.

Conclusion

Within the limitations of this study, it can be concluded that the high-impact acrylic resin is a suitable denture base material for patients with clinical fracture of the acrylic denture.  相似文献   
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Objectives:To assess the usefulness of sonographically measured anogenital distance (AGD) in predicting fetal gender in Saudi fetuses during the first trimester and to provide normal reference centiles for AGD.Methods:A retrospective cohort study was conducted at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia between November 2020 and May 2021. The ultrasound scans of 313 singleton pregnancies between 11–13 plus 6 gestational weeks and their gender-at-birth were collected. Anogenital distance was measured from the inferior base of the genital tubercle to the rump. Binominal logistic regression and receiver operating characteristic curves (ROC) evaluated the predictive performance of AGD for determining fetal gender.Results:There was a significant difference of approximately 15% in mean AGD between female (5.92 mm [95% CI= 6.70, 6.14]) and male (6.80 mm [95% CI= 6.61,7.00]) fetuses (p<0.001). Anogenital distance significantly correlated with gestational age (r=0.573, p<0.001) and crown-rump length (r=0.562, p<0.001). The logistic regression determined AGD as a significant predictor of fetal gender (p<0.001). However, ROC analysis showed that overall accuracies were low at 68% (p=0.001) for 11 weeks, 70% (p<0.001) for 12 weeks, and 64% (p=0.017), and for 13 weeks. The average AGD of our Saudi cohort was longer than what the literature reported from other populations.Conclusion:The first-trimester ultrasound evaluation of AGD was feasible and reliable. It showed a difference between the genders but did not yield high predictive accuracy. Future research should consider racial factors when evaluating AGD.  相似文献   
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Objective

Traditionally vascular rings in infants and children are treated through an open thoracotomy. Recently, thoracoscopic surgery has been used for these complex procedures. This study reports our early experience with thoracoscopic division of vascular rings and evaluates the efficacy and safety of this approach.

Material and Methods

Patients who underwent thoracoscopic division of vascular rings at King Khalid University Hospital, Riyadh, Saudi Arabia, from December 2004 to January 2006 are included. Their data were carefully analyzed looking at demographics, clinical presentation, diagnostic modality, type of the anomaly, operative details, complications, and outcome.

Results

A total of 9 patients underwent thoracoscopic division of vascular rings. Age at surgery ranged between 2 and 108 months (mean, 24 months). Weight varied between 5.3 and 32 kg (mean, 10.3 kg). All patients were symptomatic. Computed tomographic scan was diagnostic and accurately defined the type of anomaly in all the patients. Four patients had a right aortic arch with an aberrant left subclavian artery and left ductus/ligamentum arteriosum, 2 had double aortic arches, and 3 had a right aberrant subclavian artery. One patient developed right-sided pneumothorax on the contralateral site, and another one developed apnea 12 hours after surgery, requiring mechanical ventilation. There was no mortality. Operative time ranged between 50 and 145 minutes, the mean being 107 minutes. The average hospital stay was 4 days. Five patients had their preoperative symptoms completely resolved, and the rest are showing steady improvement. The average follow-up period is 6 months.

Conclusion

Our early experience indicates that thoracoscopic division of vascular rings is safe and effective. Because it takes away the need for thoracotomy, it is likely that it can result in less postoperative pain and rapid convalescence. It also prevents the ill effects of thoracotomy and gives good cosmetic results.  相似文献   
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Statement of problem

The clinical applications of high-translucency monolithic zirconia restorations have increased. Chairside and laboratory adjustments of these restorations are inevitable, which may lead to increased roughness and reduced strength. The influence of grinding and polishing on high-translucency zirconia has not been investigated.

Purpose

The purpose of this in vitro study was to compare the roughness averages (Ra) of ground and polished zirconia and investigate whether roughness influenced strength after aging.

Material and methods

High-translucency zirconia disks were milled, sintered, and glazed according to the manufacturer’s recommendations. Specimens were randomized to 4 equal groups. Group G received only grinding; groups GPB and GPK received grinding and polishing with different polishing systems; and group C was the (unground) control group. All specimens were subjected to hydrothermal aging in an autoclave at 134°C at 200 kPa for 3 hours. Roughness average was measured using a 3-dimensional (3D) optical interferometer at baseline (Ra1), after grinding and polishing (Ra2), and after aging (Ra3). A biaxial flexural strength test was performed at a rate of 0.5 mm/min. Statistical analyses were performed using commercial software (α=.05).

Results

Group G showed a significantly higher mean value of Ra3 (1.96 ±0.32 μm) than polished and glazed groups (P<.001), which showed no statistically significant difference among them (GPB, 1.12 ±0.31 µm; GPK, 0.88 ±0.31 µm; C: 0.87 ±0.25 μm) (P>.05). Compared with baseline, the roughness of groups G and GPB increased significantly after surface treatments and after aging, whereas aging did not significantly influence the roughness of groups GPK or C. Group G showed the lowest mean value of biaxial flexural strength (879.01 ±157.99 MPa), and the highest value was achieved by group C (962.40 ±113.84 MPa); no statistically significant differences were found among groups (P>.05). Additionally, no significant correlation was detected between the Ra and flexural strength of zirconia.

Conclusions

Grinding increased the roughness of zirconia restorations, whereas proper polishing resulted in smoothness comparable with glazed surfaces. The results provide no evidence that grinding and polishing affect the flexural strength of zirconia after aging.  相似文献   
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Respiratory tract infections are a principal cause of illness and mortality in children worldwide and mostly caused by viruses. In this study, the epidemiology of 11 respiratory RNA viruses was investigated in a cohort of hospitalized children at a tertiary referral center in Riyadh from February 2008 to March 2009 using conventional and real‐time monoplex RT‐PCR assays. Among 174 nasopharyngeal aspirates, respiratory syncytial virus (RSV) was detected in 39 samples (22.41%), influenza A virus in 34 (19.54%), metapneumovirus (MPV) in 19 (10.92%), coronaviruses in 14 (8.05%), and parainfluenza viruses (PIVs) in 11 (6.32%). RSV, PIVs and coronaviruses were most prevalent in infants less than 6 months old, whereas MPV and influenza A virus were more prominent in children aged 7–24 and 25–60 months, respectively. The majority of the viruses were identified during winter with two peaks observed in March 2008 and January 2009. The presented data warrants further investigation to understand the epidemiology of respiratory viruses in Saudi Arabia on spatial and temporal basis. J. Med. Virol. 88:1086–1091, 2016 . © 2015 Wiley Periodicals, Inc.
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