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11.
R H de Vos W van Dokkum P D Olthof J K Quirijns T Muys J M van der Poll 《Food and chemical toxicology》1984,22(1):11-21
Over a period of 2 yr 126 different food items of a market basket of 16-18-yr old males were purchased every 2 months. The foodstuffs were prepared as for eating, and were combined in 12 commodity groups. Twelves samples of each food group were homogenized and analysed for 78 different chemicals, including pesticides, PCBs, bromine, heavy metals, arsenic and selenium. Thirty-four of these chemicals were detected in the various samples and the means and ranges of residue concentrations found in each food group are reported. Most chemicals were found in concentrations below the Dutch residue tolerance limits, the two exceptions were omethoate and carbendazim. Using the concentrations found in the total diet samples the daily intakes of the various chemicals were calculated. The daily intake figures were evaluated with the aid of the Acceptable Daily Intakes (ADI) recommended by FAO/WHO. For practically all chemicals examined the mean and the maximum intakes were well below the ADI. 相似文献
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Miyuki Obata Satoshi Makino Kanako Takahashi Norikazu Watanabe Takayuki Yoshida 《Platelets》2015,26(4):364-369
AbstractWe describe a successful pregnancy and delivery in a patient with platelet disorder. Prophylactic platelet transfusions ensured that there were no bleeding complications during and after cesarean section. Following delivery, we performed whole exome sequencing, using next generation sequencing, to analyze the DNA samples of the patient and her family, and to identify the disease-causing mutation or variant. To identify de-novo mutations systematically, we also analyzed DNA isolated from the parents of the patient and the neonate. We successfully identified a causative novel mutation c.419?G?>?A (p.S140N) in RUNX1 in the patient and the neonate. Mutations of RUNX1 have been reported to be associated with familial platelet disorder and with a predisposition for myelodysplasia and/or acute myeloid leukemia. The patient and the neonate require careful long-term hematological follow-up. Identification of mutations by a through whole-exome analysis using next-generation sequencing may be useful in the determination of a long-term follow-up schedule for the patient. 相似文献
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In vitro screening of hERG channels are recommended under ICH S7B guidelines to predict drug-induced QT prolongation and Torsade de Pointes (TdP), whereas proarrhythmia is known to be evoked by blockage of other ion channels involved in cardiac contraction and compensation mechanisms. A consortium for drug safety assessment using human iPS cells-derived cardiomyocytes (hiPS-CMs), CSAHi, has been organized to establish a novel in vitro test system that would enable better prediction of drug-induced proarrhythmia and QT prolongation. Here we report the inter-facility and cells lot-to-lot variability evaluated with FPDc (corrected field potential duration), FPDc10 (10% FPDc change concentration), beat rate and incidence of arrhythmia-like waveform or arrest on hiPS-CMs in a multi-electrode array system.Arrhythmia-like waveforms were evident for all test compounds, other than chromanol 293B, that evoked FPDc prolongation in this system and are reported to induce TdP in clinical practice. There was no apparent cells lot-to-lot variability, while inter-facility variabilities were limited within ranges from 3.9- to 20-folds for FPDc10 and about 10-folds for the minimum concentration inducing arrhythmia-like waveform or arrests.In conclusion, the new assay model reported here would enable accurate prediction of a drug potential for proarrhythmia. 相似文献
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气相色谱法测定陈皮中有机磷农药的残留量 总被引:1,自引:0,他引:1
目的建立气相色谱法测定不同产地陈皮药材中14种有机磷农药的残留量。方法采用毛细管气相色谱法;色谱柱为HP-5毛细管色谱柱((30m×0.32mm×0.25μm);柱温50℃维持1min,以20℃/min升温至140℃,再以13℃/min升温至250℃,维持10min;检测器:FPD,温度:250℃。外标法测定陈皮中有机磷农药的残留量。结果建立的色谱方法在所考察的浓度范围内线性关系良好,各加样回收率符合要求。结论所建GC-FPD法能满足陈皮中14种有机磷农药残留定性、定量的检测要求。 相似文献
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目的:对血液中的毒鼠强进行提取和检测.方法:采用酸水解及GC/FPD、GC/MS分析的方法,研究酸水解过程中的水解温度、水解强度等方面的影响,并对毒鼠强的GC/MS图谱进行解析,建立了一个定性准确、提取效率高、干扰少的毒鼠强提取分析方法.结果:毒鼠强工作曲线在0.01~0.2μm/μl之间呈线性关系,相关系数r=0.9999.与传统的液-液提取方法相比,血液样品毒鼠强的检出率提高1.69倍.结论:本方法可应用于生物样品中毒鼠强的提取和检测. 相似文献
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Sanket R. Nagarkar Jorge Perdigão Wook-Jin Seong Nicole Theis-Mahon 《Journal of the American Dental Association (1939)》2018,149(2):139-147.e1
Background
The primary objective of this systematic review was to investigate the survival of full-coverage restorations fabricated by using digital impressions (DIs) versus that of those fabricated by using conventional impressions. The authors also compared secondary outcomes of marginal and internal fit and occlusal and interproximal contacts.Types of Studies Reviewed
The authors conducted a systematic literature search in multiple databases to identify clinical trials with no restrictions by publication type, date, or language. The authors assessed study-level risk of bias and outcome-level strength of evidence. The authors performed a meta-analysis by using a random-effects model.Results
Ten studies met the inclusion criteria. The authors identified no studies in which the investigators compared the impression techniques with respect to survival of full-coverage restorations. Mean differences for marginal gap and internal gap were ?9.0 micrometers (95% confidence interval, ?18.9 to 0.9) and ?15.6 μm (95% confidence interval, ?42.6 to 11.4), respectively. Studies assessing internal gap were substantially heterogeneous (I2 = 72%; P = .003).Conclusions and Practical Implications
Research is lacking to draw robust conclusions about the relative benefits of DIs in terms of restoration survival. Low-quality evidence for marginal fit and internal fit suggested similar performance for both techniques. Evidence quality for interproximal contact and occlusal contact was very low and insufficient to draw any conclusions regarding how the impression techniques compared. Given the uncertainty of the evidence, results should be interpreted with caution. With increasing popularity and adoption of digital scanners by dentists, pragmatic practice-based trials involving standardized, patient-centered outcomes may improve confidence in the comparative effectiveness of DIs. 相似文献17.
Karl Martin Lehmann Michael Weyhrauch Monika Bjelopavlovic Herbert Scheller Henning Staedt Peter Ottl Peer W. Kaemmerer Stefan Wentaschek 《Materials》2021,14(10)
Background: CAD/CAM systems enable the production of fixed partial dentures with small and reproducible internal and marginal gaps. Purpose: The purpose of this study was to evaluate the reproducibility of the marginal and internal adaptations of four-unit fixed partial denture frameworks produced using four CAD/CAM systems. Materials and Methods: Prepared dies of a master model that simulated the loss of the first left molar were measured. Fifteen frameworks were manufactured using four CAD/CAM systems (A–D). The internal fit was determined by the replica technique, and the marginal gap was determined by microscopy. ANOVA was carried out to detect significant differences, and the Bonferroni adjustment was performed. The global level of significance was set at 5%. Results: The mean gap size ranged from 84 to 132 µm (SD 43–71 µm). The CAD/CAM systems showed significant variance (p < 0.001), and system A (VHF) showed the smallest gaps. The smallest gaps for each system were in the molar part and in the marginal region of the frameworks (p < 0.001). Conclusions: The CAD/CAM systems showed significantly different gap sizes, particularly between premolars and molars and among the marginal, axial and occlusal regions. All of the systems are suitable for clinical application. 相似文献
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Claudia V. Turco Jenin El-Sayes Mitchell J. Savoie Hunter J. Fassett Mitchell B. Locke Aimee J. Nelson 《Brain stimulation》2018,11(1):59-74
Transcranial magnetic stimulation (TMS) is an ideal technique for non-invasively stimulating the brain and assessing intracortical processes. By delivering electrical stimuli to a peripheral nerve prior to a TMS pulse directed to the motor cortex, the excitability and integrity of the sensorimotor system can be probed at short and long time intervals (short latency afferent inhibition, long latency afferent inhibition). The goal of this review is to detail the experimental factors that influence the magnitude and timing of afferent inhibition in the upper limb and these include the intensity of nerve and TMS delivery, and the nerve composition. Second, the neural mechanisms of SAI are discussed highlighting the lack of existing knowledge pertaining to LAI. Third, the usage of SAI and LAI as a tool to probe cognition and sensorimotor function is explored with suggestions for future avenues of research. 相似文献