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Maternal supplementation alone with Lactobacillus rhamnosus HN001 during pregnancy and breastfeeding does not reduce infant eczema 下载免费PDF全文
Kristin Wickens Christine Barthow Edwin A. Mitchell Thorsten V. Stanley Gordon Purdie Judy Rowden Janice Kang Fiona Hood Lieke van den Elsen Elizabeth Forbes‐Blom Isobel Franklin Phillipa Barnes Penny Fitzharris Robyn M. Maude Peter Stone Peter Abels Rinki Murphy Julian Crane 《Pediatric allergy and immunology》2018,29(3):296-302
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Aramandla Ramesh Michael Greenwood Frank Inyang Darryl B. Hood 《Inhalation toxicology》2013,25(6):533-553
Bioavailability and toxicokinetic studies are essential in order to establish dose-response relationships of widely distributed environmental toxicants such as benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon. Fischer 344 rats were exposed for 4 h (via nose-only inhalation) to aerosol exposure concentrations of 0.1, 1.0, and 2.5 mg/m3 of BaP absorbed onto carbon black particles using a state-of-the-art model aerosol generation system. Nominal and chamber concentrations of the particulate aerosol were determined gravimetrically with a seven-stage cascade impactor. The average aerosol for the 3 exposure concentrations used in this study exhibited a trimodal distribution with 93% cumulative mass less than 15.85 µm, 89% cumulative mass less than 10 µm, 55.3% cumulative mass less than 2.5 µm, and 38% less than 1 µm. Fifty-five percent of the aerosol had a cumulative mass less than PM2.5 相似文献
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Prasanthi Maddali Marc Moisi Jeni Page Parthasarathi Chamiraju Christian Fisahn Rod Oskouian R. Shane Tubbs 《Clinical anatomy (New York, N.Y.)》2017,30(3):342-346
Epidural anesthesia is a versatile technique widely used in treating lumbar spinal pain syndromes. Complications during these procedures can arise either from needle placement or from administration of medication. Potential risks include infection, hematoma, intravascular or subdural injections of medication, direct nerve trauma, air embolism, entry into a disc space, urinary retention, radiation exposure, and hypersensitivity reactions. The objective of this article is to review the complications of lumbar epidural injections and discuss the potential pitfalls related to these procedures. We searched Medline comprehensively for relevant case reports, clinical trials, and review articles. Complications from lumbar epidural injections are extremely rare. Most if not all of them can be avoided by careful techniques with accurate needle placement, sterile precautions, and a thorough understanding of the relevant anatomy and contrast patterns on fluoroscopic imaging. Clin. Anat. 30:342–346, 2017. © 2017 Wiley Periodicals, Inc. 相似文献
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Libani IV Guy EC Melchiori L Schiro R Ramos P Breda L Scholzen T Chadburn A Liu Y Kernbach M Baron-Lühr B Porotto M de Sousa M Rachmilewitz EA Hood JD Cappellini MD Giardina PJ Grady RW Gerdes J Rivella S 《Blood》2008,112(3):875-885
In β-thalassemia, the mechanism driving ineffective erythropoiesis (IE) is insufficiently understood. We analyzed mice affected by β-thalassemia and observed, unexpectedly, a relatively small increase in apoptosis of their erythroid cells compared with healthy mice. Therefore, we sought to determine whether IE could also be characterized by limited erythroid cell differentiation. In thalassemic mice, we observed that a greater than normal percentage of erythroid cells was in S-phase, exhibiting an erythroblast-like morphology. Thalassemic cells were associated with expression of cell cycle–promoting genes such as EpoR, Jak2, Cyclin-A, Cdk2, and Ki-67 and the antiapoptotic protein Bcl-XL. The cells also differentiated less than normal erythroid ones in vitro. To investigate whether Jak2 could be responsible for the limited cell differentiation, we administered a Jak2 inhibitor, TG101209, to healthy and thalassemic mice. Exposure to TG101209 dramatically decreased the spleen size but also affected anemia. Although our data do not exclude a role for apoptosis in IE, we propose that expansion of the erythroid pool followed by limited cell differentiation exacerbates IE in thalassemia. In addition, these results suggest that use of Jak2 inhibitors has the potential to profoundly change the management of this disorder. 相似文献
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BACKGROUND. Short-term cholesterol feeding has been shown to affect vasomotor tone and increase infarct size in anesthetized rabbits. The purpose of the study was to determine whether acute hypercholesterolemia reduced collateral flow to ischemic myocardium and increased infarct size in the awake dog. METHODS AND RESULTS. Acute myocardial infarction was produced in awake dogs by a 4-hour left anterior descending coronary artery occlusion followed by 6-hour reperfusion after either a cholesterol-supplemented diet (n = 14) or a control diet of dog chow (n = 15) for 10 days. Infarct size was determined using nitroblue tetrazolium staining. In two subgroups, a 15-minute transient occlusion of the left anterior descending coronary artery was produced before the diet treatments and was compared with occlusion after diet treatments, so that the effects of hypercholesterolemia of collateral flow could be determined by paired comparisons. Cholesterol feeding increased plasma cholesterol to 288 +/- 52 mg/dl, which was twofold to threefold that in the control group (127 +/- 35 mg/dl), but had no effects on baseline systemic hemodynamics and myocardial blood flow. Coronary artery occlusion produced similar increases in heart rate, mean aortic pressure, left atrial pressure, and plasma norepinephrine in both groups of animals. However, cholesterol feeding reduced collateral flow to ischemic myocardium and increased infarct size, compared with the control group. The infarct size correlated with ischemic myocardial blood flow in both groups, but the slopes of regression lines relating the two variables did not differ between the two groups. CONCLUSIONS. Short-term, diet-induced hypercholesterolemia increased infarct size in awake dogs. This change results, at least in part, from a decrease in collateral blood flow to ischemic myocardium during coronary artery occlusion. 相似文献