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91.
PURPOSE: To evaluate in vitro the curing effect of a very high intensity light-emitting diode (LED) unit and a conventional LED unit (including "soft-start" modes) on the microleakage of a pit and fissure sealant. METHODS: 120 intact caries-free human molars were randomly divided into six groups (n=20), sealed with Fissurit-F and polymerized using either a conventional halogen unit (Optilux) (Control group) in standard mode (40 seconds @ 600 mW/cm2); a very high intensity LED unit (Mini LED) in fast (10 seconds @ 1,100 mW/cm2) or soft-start mode (pulse mode: ten 1-second flashes @ 1,100 mW/cm2; exponential mode: exponential increase from 0 to 1,100 mW/cm2 within 10 seconds followed by 10 seconds @1,100 mW/cm2); or a conventional LED unit (Elipar Freelight) in standard (40 seconds @ 400 mW/cm2) or exponential mode (exponential increase from 0 to 400mW/cm2 within 12 seconds followed by 28 seconds @ 400 mW/cm2). Restored specimens were stored in distilled water at 37 degrees C for 24 hours. Specimens were then immersed in a 0.5% fuchsin dye solution for 24 hours, with half of the specimens from each group subjected to thermocycling (5/55 degrees C; x 1000) prior to dye immersion. After removal from the dye solution, specimens were sectioned and the degree of dye penetration scored. Data was statistically analyzed using the Kruskal-Wallis H test and the Mann-Whitney U-test (P< 0.05). RESULTS: There was no statistically significant difference in microleakage of pit and fissure sealant polymerized using various curing techniques. Thermocycling regimens had no effect on either LED- or halogen-cured specimens. 相似文献
92.
肝细胞肝癌是我国常见的恶性肿瘤之一,是指由肝细胞或肝内胆管细胞发生的癌肿,死亡率高[1]。肝细胞肝癌的病因和发病机理尚未明确,起病隐匿,病情发展迅速,早期手术切除是最有效的治疗方法[1-2]。异常凝血酶原(protein induced by vitamin K absence or antagonist-Ⅱ,PIVKA-Ⅱ)是指由于维生素K缺乏或者由于服用维生素K拮抗剂而产生的异常蛋白质。PIVKA-Ⅱ是凝血Ⅱ因子(凝血酶原)的PIVKA体,因此也被称为异常凝血酶原。 相似文献
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Kjetil Sagerup Kjetil Åsbakk Anuschka Polder Janneche U. Skaåre Geir W. Gabrielsen Robert T. Barrett 《Journal of toxicology and environmental health. Part A》2014,77(9-11):481-494
Have Although persistent organic pollutants (POPs) may affect the immune system, few field studies actually examined this effect. There are indications that POP exert effects on the immune system; however, in the Arctic ecosystem data are scarce. The aim of this study was to examine immune functions in two medium trophic-positioned seabirds, the black-legged kittiwakes (Rissa tridactyla) and Atlantic puffins (Fratercula arctica). Overall POP concentrations were higher in kittiwakes than puffins and males had significantly higher concentrations than females. Mean concentrations of total polychlorinated biphenyls (ΣPCB9) were 4700 ± 200 and 9600 ± 1400 ng/g lipid weight and 2800 ± 180 and 3900 ± 200 ng/g lipid weight in female and male kittiwake and puffin blood, respectively. Levels of immunoglobulin-Y (IgY) in blood of kittiwakes were not markedly affected by concentrations of POP. Similarly, the primary IgY response to tetanus toxoid was not affected by POP concentrations in a subsample of immunized kittiwakes. In puffins, there were significant correlations between the IgY-response and some of the POPs, but with low explanatory values. These results suggest that POPs concentrations were lower than, or just at the threshold level for effects of the proposed IgY biomarker. It is also conceivable that the IgY levels are not a suitable endpoint for evaluating perturbation of the immune system in free-living seabirds. 相似文献
97.
Virginia Gonzalez Kerstin Sandelin Anders Karlsson Wiveca Åberg Lars Löfgren Gabriela Iliescu Staffan Eriksson Brita Arver 《World journal of surgery》2014,38(7):1685-1693
Background
Breast magnetic resonance imaging (MRI) has shown high sensitivity in determining tumor extent, multifocality, and occult contralateral breast cancer. Low specificity, unnecessary mastectomies, and costs are arguments against MRI. The purpose of this study was to determine whether preoperative breast MRI would affect primary surgical management, reduce reexcision/reoperation procedures, and influence the choice of neoadjuvant treatment in patients with newly diagnosed breast cancer.Methods
This prospective, randomized, multicenter study included 440 breast cancer patients younger than aged 56 years from three, Swedish, large-volume breast units. Patients were randomly allocated on a 1:1 basis to either preoperative staging with breast MRI (n = 220) or no breast MRI (n = 220) (control group). Treatment planning of all patients was discussed at multidisciplinary team conferences.Results
In patients randomized to the MRI group, who had an observed higher percentage of planned breast-conserving surgery (BCS) compared with the control group, a change from suggested breast conservation to mastectomy occurred in 23 of 153 (15 %) patients. Breast MRI provided additional information in 83 of 220 (38 %) patients, which caused a change in treatment plan in 40 (18 %). The breast reoperation rate was significantly lower in the MRI group: 11 of 220 (5 %) versus 33 of 220 (15 %) in the control group (p < 0.001). The number of mastectomies, axillary reoperations, and the number of patients receiving neoadjuvant chemotherapy after definitive treatment did not differ significantly between the groups.Conclusions
Preoperative staging with breast MRI in women younger than age 56 years altered the treatment plan in 18 % of the patients. Although a higher MRI-related conversion rate from breast conservation to mastectomy was found, the final numbers of mastectomies did not differ between the two groups. The breast reoperation rate in the MRI group was significantly reduced. 相似文献98.
T. Ueland H. Rollag A. Hartmann A. G. Jardine A. Humar A. E. Michelsen A. A. Bignamini A. Åsberg P. Aukrust 《American journal of transplantation》2014,14(1):210-215
We evaluated secreted wingless (Wnt) modulators during cytomegalovirus (CMV) infection in solid organ transplant recipients (SOTr). The major findings were: (i) Plasma levels of Dickkopf‐1 (DKK‐1) were significantly lower in patients with CMV DNAemia above lower level of quantification at baseline. (ii) Receiver operating characteristic analysis indicated that low DKK‐1 and increased secreted frizzled related protein‐3 levels were predictors of poor virological outcomes during follow‐up. Our findings demonstrate an imbalanced pattern of circulating secreted Wnt modulators in SOTr with poor virological outcomes following treatment for CMV disease, and may suggest a role for dysregulated Wnt signaling on viral pathogenesis during CMV infection. 相似文献
99.
Ingrid Lunde Sara Bremer Karsten Midtvedt Beata Mohebi Miriam Dahl Stein Bergan Anders Åsberg Hege Christensen 《European journal of clinical pharmacology》2014,70(6):685-693
Purpose
Tacrolimus (Tac) and cyclosporine (CsA) are mainly metabolized by CYP3A4 and CYP3A5. Several studies have demonstrated an association between the CYP3A5 genotype and Tac dose requirements. Recently, CYP3A4, PPARA, and POR gene variants have been shown to influence CYP3A metabolism. The present study investigated potential associations between CYP3A5*3, CYP3A4*22, PPARA c.209-1003G>A and c.208?+?3819A>G, and POR*28 alleles and dose-adjusted concentrations (C/D) of Tac and CsA in 177 renal transplant patients early post-transplant.Methods
All patients (n?=?177) were genotyped for CYP3A4*22, CYP3A5*3, POR*28, PPARA c.209-1003G>A, and PPARA c.208?+?3819A>G using real-time polymerase chain reaction (PCR) and melting curve analysis with allele-specific hybridization probes or PCR restriction fragment length polymorphisms (RFLP) methods. Drug concentrations and administered doses were retrospectively collected from patient charts at Oslo University Hospital, Rikshospitalet, Norway. One steady-state concentration was collected for each patient.Results
We confirmed a significant impact of the CYP3A5*3 allele on Tac exposure. Patients with POR*28 and PPARA variant alleles demonstrated 15 % lower (P?=?0.04) and 19 % higher (P?=?0.01) Tac C0/D respectively. CsA C2/D was 53 % higher among CYP3A4*22 carriers (P?=?0.03).Conclusion
The results support the use of pre-transplant CYP3A5 genotyping to improve initial dosing of Tac, and suggest that Tac dosing may be further individualized by additional POR and PPARA genotyping. Furthermore, initial CsA dosing may be improved by pre-transplant CYP3A4*22 determination. 相似文献100.
Strain differences influence timing and magnitude of both acute and late inflammatory reactions after intratracheal instillation of an alkylating agent in rats 下载免费PDF全文
Åsa Gustafsson Linda Svensson‐Elfsmark Johnny C. Lorentzen Anders Bucht 《Journal of applied toxicology : JAT》2014,34(3):272-280
The acute pulmonary responses after exposure to sulfur and nitrogen mustards are well documented whereas the late pulmonary effects are not. With a novel focus on the immune system this paper investigate whether late phase pulmonary effects developed in rats exposed to the nitrogen mustard melphalan are linked to the acute responses and whether the reactions are genetically regulated. The DA rat strain was used to establish a lung exposure model. Five other inbred rat strains (PVG, PVG.1AV1, LEW, WF and F344) were compared within the model at selected time points. All rat strains displayed a biphasic pattern of leukocyte infiltration in the lungs, dominated by neutrophils 2 days after exposure and a second peak dominated by macrophages 29 days after exposure. The number of macrophages was higher in the DA rat compared with the other strains. The infiltration of lymphocytes in the lungs varied in both time of appearance and magnitude between strains. The quantity of collagen deposition in the lungs varied between strains at day 90; LEW and WF displayed high collagen content which coincided with an increased level of cytotoxic T cells. LEW further displayed an increased number of T helper cells and natural killer (NK) T cells in the lungs. The results in this study suggest there is a link between the development of lung fibrosis and high cytotoxic cell responses and that there is a genetic influence, as there are variations in acute and late adverse reactions between rat strains in both timing and magnitude. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献