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81.
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83.
This study aimed to investigate the influence of silicone oil on the retinal nerve fiber layer (RNFL) thickness in patients with primary rhegmatogenous retinal detachment who underwent vitreoretinal surgery. The study included 47 patients (eyes), who underwent a pars plana vitrectomy with the silicone oil tamponade. The control group included unoperated eye of all participants. Spectral-domain optical coherence tomography (SD-OCT) was used for the measurements of peripapilar and macular RNFL thickness. The average peripapillary RNFL thickness was significantly higher in the silicone oil filled eyes during endotamponade and after its removal. The eyes with elevated IOP had less thickening of the RNFL in comparison to the eyes with normal IOP. Central macular thickness and macular volume were decreased in the silicone oil filled eyes in comparison to the control eyes. In conclusion, silicone oil caused peripapilar RNFL thickening in the vitrectomized eyes during endotamponade and after silicone oil removal.  相似文献   
84.
A recent study showed that tetrahydrofuran (THF), a widely used solvent, is carcinogenic in experimental animals. Despite its carcinogenic activity, there is a paucity of information regarding cellular toxicity, biomolecular damage, and genotoxicity induced by THF. We describe here the structural characterization of adducts produced by the reaction of oxidized THF with 2'-deoxyguanosine (dGuo-THF 1 and dGuo-THF 2), 2'-deoxyadenosine (dAdo-THF), and 2'-deoxycytidine (dCyd-THF). Adducts were isolated from in vitro reactions by reverse-phase HPLC and fully characterized on the basis of spectroscopic measurements. The stable derivatives obtained by the reduction of adducts with NaBH(4) (the case of dGuo-THF 1, dCyd-THF, and dAdo-THF) and the stable adduct dGuo-THF 2 were used as standards for optimization of chromatographic separations for adduct detection in DNA through HPLC/ESI/MS-MS. Using this methodology, we successfully detected the four adducts in calf thymus DNA reacted with oxidized THF. The present study also provides evidence that rat liver microsomal monooxigenases oxidize THF to the reactive electrophilic compounds that are able to damage the DNA molecule, as indicated by a significant increase in adduct dGuo-THF 1 level when NADPH was added to the THF/microsomes/dGuo incubation mixtures. Our data point to DNA-THF adducts as possible contributing factors to the toxicological effects of THF exposure.  相似文献   
85.
This article is dedicated to investigating the properties of soil after its reinforcement with fiberglass elements through large-scale laboratory plate-load tests of various samples that varied in the numbers and lengths of the reinforcing elements. The investigation of the vertical elements considered the diameter increase at the bottom toe by using widening washers. The results were compared relative to each other and to the theoretical calculation results. The theoretical calculations for the settlements were undertaken based on the authors’ proposed method. The method considers the number, shape, area and material of the strengthening elements using a pre-proposed reinforcement area factor µ. This pre-established factor was calculated with reference to the elements’ geometry—the diameter of the vertical elements and the bottom’s washer diameter—which determined the reinforcement area. A comparison between the reinforced and reference soft sandy soil samples indicated a 25% increase in the deformation modulus after the reinforcement process at a pressure of 25 kPa. Samples with µ ranging from 1.20 to 1.43 were 55–65% stiffer than samples with µ equal to 0.69 at a pressure of 100 kPa. The comparative analysis of the calculated results and the actual laboratory PLT test results was adequate for use for further development.  相似文献   
86.
The aim of the present study is to develop and implement a methodology that accounts for parameter variability and uncertainty in the presence of qualitative and semi-quantitative information (fuzzy simulations) as well as when some parameters are better quantitatively defined than others (fuzzy-probabilistic approach). The fuzzy simulations method consists of (i) representing parameter uncertainty and variability by fuzzy numbers and (ii) simulating predictions by solving the pharmacokinetic model. The fuzzy-probabilistic approach includes an additional transformation between fuzzy numbers and probability density functions. To illustrate the proposed method a diazepam WBPBPK model was used where the information for hepatic intrinsic clearance determined by in vitro-in vivo scaling was semi-quantitative. The predicted concentration time profiles were compared with those resulting from a Monte Carlo simulation. Fuzzy simulations can be used as an alternative to Monte Carlo simulation.  相似文献   
87.
A eucaloric very low carbohydrate diet (EVLCD) is a diet with a daily caloric intake equal to the total daily energy expenditure (TDEE) with a carbohydrate content of <50 g/day. The literature on very low carbohydrate diets (VLCD) in type 1 diabetes (DM 1) is limited, although recently published scientific studies have highlighted their safety and efficacy in managing DM 1. In this retrospective analysis, we report the clinical data of 33 patients affected by DM 1 carrying out insulin therapy who switched voluntarily from their usual diet (high carb, low fat) to an EVLCD. Our aim is to evaluate the glycemic control, the amount of insulin needed in order to maintain glycemic control and safety of EVLCD. The switch improved glycemic control (mean glycated hemoglobin decreased from 8.3% to 6.8% (p < 0.01). The number of patients who reached a glycated hemoglobin value of <7% increased statistically from 12% to 57% (p < 0.01), and there was a statistically significant decrease (p < 0.01) in the units of daily insulin (from 36.7± 14.9 IU to 28.9 ±9.1 IU) A reduction from 54% to 24% in clinical level 2 hypoglycemia episodes was reported. No cases of severe hypoglycemia or ketoacidosis were observed. The results of the study support that EVLCD in DM 1 seems safe and effective when adopted under tight medical supervision.  相似文献   
88.
Low-grade systemic inflammation is associated with a range of conditions. Diet may modulate inflammation and public health strategies are needed to guide consumers’ dietary choices and help prevent diet-related disease. The Food Standards Agency nutrient profiling system (FSAm-NPS) constitutes the basis of the five-colour front-of-pack Nutri-Score labelling system. No study to date has examined FSAm-NPS dietary index associations with biomarkers of inflammation. Therefore, our objective was to test relationships between the FSAm-NPS and a range of inflammatory biomarkers in a cross-sectional sample of 2006 men and women aged 46–73 years. Individual participant FSAm-NPS scores were derived from food frequency questionnaires. Pro-inflammatory cytokine, adipocytokine, acute-phase response protein, coagulation factor and white blood cell count concentrations were determined. Correlation and linear regression analyses were used to examine FSAm-NPS relationships with biomarker levels. In crude and adjusted analyses, higher FSAm-NPS scores, reflecting poorer nutritional quality, were consistently and positively associated with biomarkers. In fully adjusted models, significant associations with concentrations of complement component 3, c-reactive protein, interleukin 6, tumour necrosis factor alpha, resistin, white blood cell count, neutrophils, eosinophils and the neutrophil-to-lymphocyte ratio persisted. These results suggest that dietary quality, determined by Nutri-Score rating, is associated with inflammatory biomarkers related to health.  相似文献   
89.
Fetal stroke is an important cause of cerebral palsy but is difficult to diagnose unless imaging is undertaken in pregnancies at risk because of known maternal or fetal disorders. Fetal ultrasound or magnetic resonance imaging may show haemorrhage or ischaemic lesions including multicystic encephalomalacia and focal porencephaly. Serial imaging has shown the development of malformations including schizencephaly and polymicrogyra after ischaemic and haemorrhagic stroke. Recognised causes of haemorrhagic fetal stroke include alloimmune and autoimmune thrombocytopaenia, maternal and fetal clotting disorders and trauma but these are relatively rare. It is likely that a significant proportion of periventricular and intraventricular haemorrhages are of venous origin. Recent evidence highlights the importance of arterial endothelial dysfunction, rather than thrombocytopaenia, in the intraparenchymal haemorrhage of alloimmune thrombocytopaenia. In the context of placental anastomoses, monochorionic diamniotic twins are at risk of twin twin transfusion syndrome (TTTS), or partial forms including Twin Oligohydramnios Polyhydramnios Sequence (TOPS), differences in estimated weight (selective Intrauterine growth Retardation; sIUGR), or in fetal haemoglobin (Twin Anaemia Polycythaemia Sequence; TAPS). There is a very wide range of ischaemic and haemorrhagic injury in a focal as well as a global distribution. Acute twin twin transfusion may account for intraventricular haemorrhage in recipients and periventricular leukomalacia in donors but there are additional risk factors for focal embolism and cerebrovascular disease. The recipient has circulatory overload, with effects on systemic and pulmonary circulations which probably lead to systemic and pulmonary hypertension and even right ventricular outflow tract obstruction as well as the polycythaemia which is a risk factor for thrombosis and vasculopathy. The donor is hypovolaemic and has a reticulocytosis in response to the anaemia while maternal hypertension and diabetes may influence stroke risk. Understanding of the mechanisms, including the role of vasculopathy, in well studied conditions such as alloimmune thrombocytopaenia and monochorionic diamniotic twinning may lead to reduction of the burden of antenatally sustained cerebral palsy.  相似文献   
90.
An adolescent with complaints of fatigue, tachycardia, abdominal discomfort, and blood-stained diarrhea is presented. Clinical and laboratory evaluation revealed a microcytemic anemia with iron deficiency, beta thalassemia, and thyrotoxicosis with thyroid antibodies. Crohn’s disease was confirmed on endoscopy. A rapid normalization of clinical and laboratory parameters was observed following the initiation of therapy and further exacerbation of her illness was prevented. Although the simultaneous occurrence of Crohn’s disease, autoimmune thyroiditis, and a beta-thalassemia trait is likely to be coincidental, the combination of an autoimmune thyroid disease and Crohn’s disease is rare in pediatrics. Several issues of importance in the treatment of these conditions are discussed. Rectal blood loss associated with Crohn’s disease may lead to severe iron deficiency, especially in patients with preexistent beta-thalassemia trait, and those with thyroiditis are prone to developing hypothyroidism following treatment, requiring that they be monitored closely.  相似文献   
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