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41.
Purpose: To determine whether prophylaxis with etanercept, an anti-inflammatory drug, would decrease the severity of lung injury in a neonatal rat model of bronchopulmonary dysplasia (BPD); Materials and Methods: Rat pups were divided into three groups: pups exposed to room air (group 1; n = 10), to hyperoxia + placebo (group 2; n = 9), and to hyperoxia + etanercept (group 3; n = 8). Lung morphology was assessed by alveolar surface area percentage, which is a measure of alveolar size. The severities of lung inflammation and antioxidant capacity were assessed by quantifying tumor necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β), malondialdehyde (MDA), and superoxide dismutase (SOD) from lung homogenate; Results: The percentage of alveolar surface areas were significantly higher in group 3 compared to group 2 (p = .004) and similar in both group 1 and group 3 (p = .21). The mean level of lung MDA was significantly higher in group 2 compared to group 1 and group 3 (p < .05 for both). Lung homogenate SOD activities in group 3 was significantly higher than group 2 (p < .001). Furthermore, group 3 pups had lower levels of TNF-α and TGF-β in lung homogenate than that in group 2 (p < .05 for both) but similar in both group 1 and group 3; Conclusion: Etanercept has favorable effects on alveolarization as well as inflammation and oxidative stress markers in a neonatal rat model of BPD.  相似文献   
42.
The feasibility of transabdominal near-infrared (NIR) spectroscopy for detecting and quantifying fetal hypoxia in utero is demonstrated in a pregnant ewe model. A frequency domain NIR spectroscopy probe, consisting of two detectors and six sources operating at three wavelengths (675, 786, and 830 nm), was placed on the maternal abdomen directly above the fetal head. Fetal hypoxia was indirectly induced through occlusion of uterine blood flow for approximately 3 min. NIR photon diffusion measurements were made during a baseline period, during hypoxia of the fetus, and during recovery. Fetal blood samples were drawn from the fetal brachial artery and jugular veins at several time points during the cycle. Seven hypoxic cycles were induced in a total of five pregnant ewes. The NIR measurements were analyzed by using a two-layer diffusion model to deconvolve the fetal blood saturation from that of the pregnant ewe. Fetal hypoxia was detected. Good agreement was found between fetal blood saturation determined by the transabdominal NIR method and arterial and venous fetal blood saturation quantified from fetal blood samples by using a hemoximeter.  相似文献   
43.

Introduction

Head-of-bed manipulation is commonly performed in the neurocritical care unit to optimize cerebral blood flow (CBF), but its effects on CBF are rarely measured. This pilot study employs a novel, non-invasive instrument combining two techniques, diffuse correlation spectroscopy (DCS) for measurement of CBF and near-infrared spectroscopy (NIRS) for measurement of cerebral oxy- and deoxy-hemoglobin concentrations, to monitor patients during head-of-bed lowering.

Methods

Ten brain-injured patients and ten control subjects were monitored continuously with DCS and NIRS while the head-of-bed was positioned first at 30° and then at 0°. Relative CBF (rCBF) and concurrent changes in oxy- (ΔHbO2), deoxy- (ΔHb), and total-hemoglobin concentrations (ΔTHC) from left/right frontal cortices were monitored for 5 min at each position. Patient and control response differences were assessed.

Results

rCBF, ΔHbO2, and ΔTHC responses to head lowering differed significantly between brain-injured patients and healthy controls (P < 0.02). For patients, rCBF changes were heterogeneous, with no net change observed in the group average (0.3 ± 28.2 %, P = 0.938). rCBF increased in controls (18.6 ± 9.4 %, P < 0.001). ΔHbO2, ΔHb, and ΔTHC increased with head lowering in both groups, but to a larger degree in brain-injured patients. rCBF correlated moderately with changes in cerebral perfusion pressure (R = 0.40, P < 0.001), but not intracranial pressure.

Conclusion

DCS/NIRS detected differences in CBF and oxygenation responses of brain-injured patients versus controls during head-of-bed manipulation. This pilot study supports the feasibility of continuous bedside measurement of cerebrovascular hemodynamics with DCS/NIRS and provides the rationale for further investigation in larger cohorts.  相似文献   
44.
45.
Hemophagocytic lymphohistiocytosis (HLH) is a clinical condition which result in cytotoxic Tcell and antigen presenting cell overproduction and also their cytokines. Hepatitis A Virus associated HLH is very rare condition among other viruses. This condition is often difficult to diagnose, so treatment is often delayed. Here we present a case of adolescent boy with secondary virus associated HLH diagnosis with Hepatitis A infection and successfull treatment by short course of intravenous immunoglobulin and steroid.  相似文献   
46.
47.

Objectives

To evaluate the cumulative effect of the abutment tooth and resin cement colour on the resultant optical properties of porcelain laminate veneers (PLVs) fabricated with leucite-based CAD/CAM blocks with different shades and thicknesses.

Methods

A total of 224 ceramic specimens were prepared from the IPS Empress CAD with four different shades of HT-A1, LT-A1, MT-A1 and Bl-1. Resin composite discs were prepared with shade A3.5. For the cementation, 4 different shades of light-cure resin cements were chosen. L*, a*, and b* values, as well as the chroma (C) and hue (h) values of each cemented ceramic and the A1 shade table, were recorded.

Results

L*, Cab* and hab* values of the cemented ceramics were influenced by ceramic shade, ceramic thickness, cement shade, and interaction terms of the three variables. There were significant differences between the 1-mm-thick ceramic veneers that exhibited higher L* and lower Cab* values compared with veneers that were 0.5 mm in thickness. Using the Tr shade cement resulted in lower L* and higher Cab* values for all thicknesses and ceramic shades, whereas the WO shade cement resulted in higher values.

Conclusions

The selected colour of a laminate restoration is significantly affected by the ceramic shade, ceramic thickness and resin cement shade. Using the WO shade resin cement seems to be more effective in masking the discoloured abutment tooth. Clinicians should also select the translucency level of the ceramic block with the shade when a leucite-based CAD/CAM system is chosen to treat a discoloured tooth.  相似文献   
48.
The aim of this study was to evaluate respiratory function tests, total eosinophil counts, serum immune globulin E (IgE), and serum concentrations of soluble intercellular adhesion molecule (sICAM)1, soluble vascular cell adhesion molecule (sVCAM) 1, and soluble P-selectin (sP-selectin) levels in the children with mild and/or moderate asthma before and 3 months after inhaled steroids and to determine whether adhesion molecule levels showed any difference between asthmatic and healthy children and whether these levels changed with disease activity. A total of 28 children with bronchial asthma and 24 children as a control group were included in the study. All of the patients in the study group were administered inhaled budesonide treatment. The patients were reevaluated 3 months later. Respiratory functions tests were performed and total eosinophil count and serum total IgE level were determined. Serum levels of sICAM-1, sVCAM-1, and sP-selectin were determined and skin-prick tests were performed. Significant difference paralleled to clinical improvement was found in the study group for respiratory function tests, total eosinophil count, serum IgE level, and sICAM-1 levels determined before and after the treatment. However, no significant difference was found for sP-selectin and sVCAM-1 levels before and after the treatment. The higher level of sICAM-1 before the treatment suggests that leukocyte-endothelial adhesion have a role in bronchial asthma, which is an inflammatory airway disease. Reduction in the level of sICAM-1 after the treatment may be related to the decreased inflammation in response to therapy. However, no strong relationships were found between the determinants representing the inflammation and respiratory function tests.  相似文献   
49.
Objective: To determine the characteristics and risk factors of drug dependence among patients who were administered drugs with addictive potential (DAP) in an emergency department (ED).Methods: This retrospective cross-sectional study included patients who were administered DAP 3 or more times in the emergency room between September 1, 2019 and March 1, 2020. The demographic and baseline information were recorded. All the prescibed DAP, the reasons to use these drugs, secondary drug dependence, the department where DAP were first prescribed, types of doctors who preferred to prescribed DAP, and the risk factors for the development of drug dependence were determined. Results: A total of 3000 patients were screened from medical records, and among them, 80 patients developed drug dependence. Drug dependence only developed for tramadol (n=57, 71.3%), diazepam (n=11, 13.8%), and biperiden (n=12, 15.0%). Tramadol was the most frequently prescribed drug (n=57, 71.3%). The most common reason for drug dependence was psychiatric disorders (n=29, 36.3%). Drug dependence developed in renal colic patients due to the administration of tramadol (n=7, 100%). On the contrary, dependence to biperiden were mainly developed in patients with psychiatric complaints (n=12, 41.4%). The rate of secondary drug dependence was 15% (n=12). Of the Biperiden users, 41.7% developed secondary drug dependence on diazepam. Most DAP were first prescribed in the ED (n=52, 65%), and the specialist preferred to prescribe DAP (n=43, 53.8%). For the development of dependence, the presence of renal colic (OR: 3.387, 95% confidence interval (CI): 1.473-7.788, P=0.004) and low back pain (OR: 5.778, 95% CI: 2.779-12.014, P<0.001) were the risk factors. Conclusions: Most DAP were first prescribed in the ED compared to other departments, and specialist are preferred to use DAP. Tramadol is the most commonly used drugs caused drug dependence. Psychiatric disorder patients are easier to develope drug dependence. Furthermore, renal colic and low back pain patients needs more attention to avert drug dependence.  相似文献   
50.
Context: In the present study, cisplatin (CP) induced eye toxicity and the beneficial effect of hesperidin (HP) was investigated.

Methods: Twenty-eight rats were equally divided into four groups; the first group was kept as control. In the second and third group, CP and HP were given at the doses of 7?mg/kg and 50?mg/kg/d, respectively. In the fourth group, CP and HP were given together at the same doses. Tissue samples were collected on day 14 of CP treatment.

Results: The results demonstrated that CP caused a significant increase in thiobarbituric acid reactive substances (TBARS) levels and decrease of glutathione levels and antioxidant enzyme activity (catalase, superoxide dismutase and glutathione peroxidase) in eye tissues compared to other groups, HP prevented these effects of CP. Besides, CP led to histopathological damage in the retina and cornea. On the other hand, HP treatment prevented histopathological effects of CP.

Conclusion: CP had severe dose-limiting toxic effects and HP treatment can be beneficial against the toxic ocular effects of CP. Thus, it appears that co-administration of HP with CP may be a useful approach to attenuate the negative effects of CP on the eye.  相似文献   
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