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51.
Clinical Rheumatology - To evaluate the impact of the coronavirus disease 2019 (COVID-19) pandemic on rheumatology practice. A cross-sectional web survey was designed by the members of the Arab...  相似文献   
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Vascular calcification (VC) is a risk factor for cardiovascular mortality in the setting of chronic kidney disease (CKD). Pyrophosphate (PPi), an endogenous molecule that inhibits hydroxyapatite crystal formation, has been shown to prevent the development of VC in animal models of CKD. However, the possibility of harmful effects of exogenous administration of PPi on bone requires further investigation. To this end, we examined by histomorphometry the bone of CKD mice after intraperitoneal PPi administration. After CKD creation or sham surgery, 10-week-old female apolipoprotein-E knockout (apoE?/?) mice were randomized to one non-CKD group or 4 CKD groups (n = 10–35/group) treated with placebo or three distinct doses of PPi, and fed with standard diet. Eight weeks later, the animals were killed. Serum and femurs were sampled. Femurs were processed for bone histomorphometry. Placebo-treated CKD mice had significantly higher values of osteoid volume, osteoid surface and bone formation rate than sham-placebo mice with normal renal function. Slightly higher osteoid values were observed in CKD mice in response to very low PPi dose (OV/BV, O.Th and ObS/BS) and, for one parameter measured, to high PPi dose (O.Th), compared to placebo-treated CKD mice. Treatment with PPi did not modify any other structural parameters. Mineral apposition rates, and other parameters of bone formation and resorption were not significantly different among the treated animal groups or control CKD placebo group. In conclusion, PPi does not appear to be deleterious to bone tissue in apoE?/? mice with CKD, although a possible stimulatory PPi effect on osteoid formation may be worth further investigation.  相似文献   
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In Lebanon and many other countries where structures are vulnerable to impact loads caused by accidental rock falls due to landslides, specifically bridges with hollow core slab, it is mandatory to develop safe and efficient design procedures to design such types of structures to withstand extreme cases of loading. The structural response of concrete members subjected to low velocity high falling weight raised the interest of researchers in the previous years. The effect of impact due to landslide falling rocks on reinforced concrete (RC) slabs has been investigated by many researchers, while very few studied the effect of impact loading on pre-stressed structures, noting that a recent study was conducted at Beirut Arab University which compared the dynamic behavior of reinforced concrete and post-tensioned slabs under impact loading from a 605 kg impactor freely dropped from a height of 20 m. Hollow core slabs are widely used in bridges and precast structures. Thus, studying their behavior due to such hazards becomes inevitable. This study focuses on these types of slabs. For a better understanding of the behavior, a full scale experimental program consists of testing a single span hollow core slab. The specimen has 6000 mm × 1200 mm × 200 mm dimensions with a 100 mm cast in a place topping slab. Successive free fall drops cases from 14 m height will be investigated on the prescribed slab having a span of 6000 m. This series of impacts will be held by hitting the single span hollow core slab at three different locations: center, edge, and near the support. The data from the testing program were used to assess the structural response in terms of experimental observations, maximum impact and inertia forces, structural damage/failure: type and pattern, acceleration response, and structural design recommendations. This research showed that the hollow core slab has a different dynamic behavior compared to the post tensioned and reinforced concrete slabs mentioned in the literature review section.  相似文献   
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Background

The purpose of this study was to compare long‐term outcomes of primary transport (PT) and secondary transport (ST) in patients with STEMI.

Method

We assigned consecutive 869 patients referred for STEMI during a 2‐year period (2008‐2009). The primary endpoint was to compare long‐term outcomes and mortality of PT to a catheterization laboratory and ST from regional hospitals to a catheterization laboratory. Six hundred seventy‐seven patients (77.9%) were enrolled for the final evaluation, 192 (22.1%) having been excluded.

Results

The median DBT was 34 ± 15.92 min for PT patients (n = 354) and 100 ± 28.82 min for ST patients (n = 323) (P < 0.005). One‐month mortality was 3.95% in the PT group versus 9.46% in the ST group (P = 0.002). One‐year mortality in the PT was 7.35% and 20.51% in the ST group (P < 0.005). Eight‐year mortality was in the PS 26.8% versus 32.6% in the ST group (P = 0.035). Left ventricular ejection fraction (LVEF) was 45 ± 12.14% versus 45 ± 12.48% (P = 0.21); creatine kinase (CK) was 22.78 ± 78.69 ukat/L versus 23.21 ± 82.61 ukat/L, (P = 0.58); and length of hospitalization was 4.98 ± 4.61 days in the PT group versus 5.25 ± 5.86 days in the ST group (P = 0.22). The air transport was used in the PT group (RR 0.85, 95% CI 0.63‐1.09); and ST group (RR 1.17, 95% CI 0.91‐1.40); P = 0.22). Time distribution of cardiac arrest median for PT 1432 days (n = 25) versus ST 266 (n = 31) P = 0.24.

Conclusion

The mortality benefits of PT to a PCI capable hospital persist throughout an 8‐year follow‐up.
  相似文献   
58.
Ultrasound-guided fine-needle aspiration and thyroid disease   总被引:2,自引:0,他引:2  
BACKGROUND: Fine-needle aspiration represents a critical diagnostic test in determining proper management of thyroid disease and the use of ultrasound-guided fine-needle aspiration (USGFNA) has increased over the years. METHODS: A retrospective chart review of patients undergoing USGFNA. Two hundred fifteen patients underwent 234 procedures with 362 nodules aspirated within a 2 (1/2)-year period. RESULTS: The mean ages of women and men were 51.9 and 57.8, respectively. The average size of nodules was 2.1 cm. A difficult to assess gland or nodule was the most common indication for USGFNA (33%). The sensitivity was 88.2%, specificity was 80.0%, the PPV was 65.2%, the negative predictive value was 94.1%, and the accuracy was 82.5%. The cancer yield, inadequacy, and complication rates were 44%, 10.5%, and 8.5%, respectively. CONCLUSIONS: USGFNA aspiration is a safe and effective diagnostic modality in the management of thyroid disease, especially for nodules that are difficult to palpate.  相似文献   
59.
PURPOSE: To estimate which combination of restorative materials resulted in the most homogeneous stress and strain distributions in post-and-core treated teeth. MATERIALS AND METHODS: Eight experimental finite element models with different material configurations were simulated; both indirect and direct restorations were considered. An arbitrary load of 50 N was applied on the palatal surface of the crown at a 60-degree angle to the tooth's longitudinal axis to simulate tearing function. RESULTS: In all the models, the values of both strain and stress recorded in the middle third of the buccal aspect of the root surface were off the scale. In contrast, the minimum values were noticed at the level of both the apical portion of the post and the root apex. CONCLUSION: The mechanical properties of the crown and core materials influenced both the position of concentration areas and the level of stress and strain along the dentin/cement/post interfaces.  相似文献   
60.
Introduction: New QT correction formulae derived from large populations are available such as Rautaharju’s [QTcRTH?=?QT * (120?+?HR)/180] and Dmitrienko’s [QTcDMT?=?QT/RR0.413]. These formulae were derived from 57,595 and 13,039 cases, respectively. Recently, a study has shown that they did not experience errors across a wide range of heart rates compared to others.

Objectives: (1) To determine the best cut-off value of QTcRTH and QTcDMT as a predictor of torsade de pointes (TdP) and (2) to compare the sensitivity and specificity using the cut-off value of QTcRTH with those of the QTcBazett (QTcBZT), QTcFridericia (QTcFRD), and QT nomogram.

Methods: Data were derived from two data sets. All cases aged over 18 years with an exposure to QT-prolonging drugs. Group-1, all cases developed TdP. Data in Group-1 were obtained from systematic review of reported cases from Medline since its establishment until 10 December 2015. Group-2 is composed of those who overdosed on QT prolonging drugs but did not develop TdP. This data set was previously extracted from a chart review of three medical centers from January 2008 to December 2010. Data from both groups were used to calculate QTcRTH and QTcDMT. The cut-off values from QTcRTH and QTcDMT that provided the best sensitivity and specificity to predict TdP were then selected. The same method was applied to find those values from QTcBZT, QTcFRD, and QT nomogram. The receiver operating characteristic curve (ROC) was applied where appropriate.

Results: Group-1, 230 cases of drug-induced TdP were included from the systematic review of Medline. Group-2 (control group), which did not develop TdP, consisted of 292 cases. After applying all of the correction methods to the two datasets, the best cut-off values that provided the best accuracy (Ac) with the best sensitivity (Sn) and specificity (Sp) for each formula were as follows: QTcRTH at 477 milliseconds (ms), Ac?=?89.08%, Sn?=?91.30% (95%CI?=?86.89–94.61), Sp?=?87.33%(95%CI?=?82.96–90.92); QTcDMT at 475?ms, Ac?=?88.31%, Sn?=91.30% (95%CI?=?86.89–94.61), Sp?=?85.96%(95%CI?=?81.44–89.73); QTcBZT at 490?ms, Ac?=?86.97%, Sn?=?88.26% (95%CI?=?83.38–92.12), Sp?=?85.96% (95%CI?=?81.44–89.73); QTcFRD at 473?ms, Ac?=?88.89%, Sn?=?89.13% (95%CI?=?84.37–92.84), Sp =88.70% (95%CI?=?84.50–92.09). We found a significant difference (p-value?=?0.0020) between area under the ROC of the QTcRTH (0.9433) and QTcBZT (0.9225) but not QTcFRD (0.9338). The Ac, Sn, and Sp of the QT nomogram were 89.08%, 91.30% (95%CI?=?86.89–94.61), and 87.33% (95%CI?=?82.96–90.92), respectively, and they were all equal to those of QTcRTH.

Conclusion: Rautaharju method not only produced minimal errors for QT interval correction but also at QTcRTH 477?ms, it could predict TdP as accurately as QT nomogram and was better than the QTcBZT.  相似文献   
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