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排序方式: 共有672条查询结果,搜索用时 15 毫秒
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Elisa Doné Leonardo Gucciardo Tim Van Mieghem Jacques Jani Mieke Cannie Dominique Van Schoubroeck Roland Devlieger Luc De Catte Philipp Klaritsch Steffi Mayer Veronika Beck Anne Debeer Eduardo Gratacos Kypros Nicolaides Jan Deprest 《黑龙江环境通报》2008,28(7):581-591
Congenital diaphragmatic hernia (CDH) can be associated with genetic or structural anomalies with poor prognosis. In isolated cases, survival is dependent on the degree of lung hypoplasia and liver position. Cases should be referred in utero to tertiary care centers familiar with this condition both for prediction of outcome as well as timed delivery. The best validated prognostic indicator is the lung area to head circumference ratio. Ultrasound is used to measure the lung area of the index case, which is then expressed as a proportion of what is expected normally (observed/expected LHR). When O/E LHR is < 25% survival chances are < 15%. Prenatal intervention, aiming to stimulate lung growth, can be achieved by temporary fetal endoscopic tracheal occlusion (FETO). A balloon is percutaneously inserted into the trachea at 26–28 weeks, and reversal of occlusion is planned at 34 weeks. Growing experience has demonstrated the feasibility and safety of the technique with a survival rate of about 50%. The lung response to, and outcome after FETO, is dependent on pre-existing lung size as well gestational age at birth. Early data show that FETO does not increase morbidity in survivors, when compared to historical controls. Several trials are currently under design. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
194.
Thermal treatments of five different types of non-ferrous metallurgical wastes, under a controlled atmosphere, were carried out at temperatures lower than 800°C for the separation of their toxic compounds and the concentration of valuable metals in the treatments residues. The best results were obtained by the treatments in air or hydrogen, or both successively. Simple treatments, using air or hydrogen, of three samples allowed the elimination of more than 95% of their toxic elements and almost doubled their valuable metals concentration. For the rest of the samples, a combined treatment was necessary for their efficient decontamination. In this case, the valuable metals content in the treatment's residue was increased to a reasonable value. Most of the solids issuing from these treatments can be recycled in current non-ferrous metallurgical processes. 相似文献
195.
A.H. El‐Sebae M.E. Abdel‐Ghanv D. Shalloway M.M. Abou Zeid J. Blancato M.A. Saleh 《Journal of environmental science and health. Part. B》2013,48(6):763-777
Abstract Phosphorylation is an indispensable process for energy and signal transduction in biological systems. AlCl3 at 10 nM to 10 uM range activated in‐vitro [γ‐32P)ATP phosphorylation of the brain (tau) T protein in both normal human or E.coli expressed T forms; in the presence of the kinases P34, PKP, and PKC. However, higher concentrations of ALCl3 inhibited the T phosphorylation with P34, PKP, and PKC to a maximum at 1 mM level. AlCl3 at 100 uM to 500 uM range induced non‐enzymatic phosphorylation of T with γ‐ATP, γ‐GTP, and α‐GTP. AlCl3 activated histone phosphorylation by P34 in a similar pattern. The hyperphosphorylation of T by Al3+ was accompanied by molecular shift and mobility retardation in SDS‐PAGE. This may demonstrate the mechanism of the longterm neurological effect of Al3+ in human brain leading to the formation of the neurofibrillary tangles related to Alzeheimer's disease. 相似文献
196.
M.J. Villarroel M.D. Ferrando E. Sancho E. Andreu 《Journal of environmental science and health. Part. B》2013,48(2):211-227
Abstract Two Daphnia magna offsprings (animals from the first and third brood) whose parentals (F0‐generation) were exposed during 21 days to different tetradifon (4‐chlorophenyl 2,4,5‐trichlophenyl sulfone) concentrations, were transferred to a pesticide free medium during 21 days (recovery period). The algae Nannochloris oculata (5x105 cells/mL) was used as food. In this recovery study, survival, growth and reproduction (mean total young per female, mean brood size, onset of reproduction and mean number broods per female) were assessed as individual parameters and the intrinsic rate of natural increase (r) as population parameter, for F1 generation (1st and 3rd broods). Reproduction was still reduced in F1 (1st and 3rd broods) generation daphnids from parentals (F0) exposed to 0.18 mg/L tetradifon and higher concentrations even after 21 days in clean water. However, survival was not significantly different (p>0.05) in those F1 offsprings from parentals pre‐exposed to the acaricide. Growth was still reduced in F1 daphnids from parentals pre‐exposed to 0.10–0.44 mg/L tetradifon. The intrinsic rate of natural increase (r) was still affected in Fl generation daphnids, specially in those from the third brood. Therefore, Fl generation D. magna offsprings from a parental generation (F0) previously exposed to the acaricide tetradifon were not able to recuperate completely when a recovery period of 21 days was allowed. 相似文献
197.
本文选择了紫背浮萍、四尾栅藻、蚤状溞和稀有鮈鲫4种本土水生生物,开展了阳离子表面活性剂、织物三防整理剂、C4三防整理剂和C6三防整理剂4种全氟辛烷磺酸盐(PFOS)替代品的安全性评估,为筛选理想PFOS化学替代品提供科学依据。急性毒性结果发现阳离子表面活性剂对4种水生生物均未显示出急性毒性;织物三防整理剂、C4三防整理剂和C6三防整理剂对蚤状溞的LC50值分别为17.97、64.61和85.58 mg·L-1,显示出低的急性毒性。另外,织物三防整理剂对四尾栅藻的半数抑制浓度(EC50)值为88.32 mg·L-1,而对稀有鮈鲫半致死浓度(LC50)值为14.79 mg·L-1,均存在急性毒性。短期生长抑制试验结果发现阳离子表面活性剂、织物三防整理剂、C4三防整理剂和C6三防整理剂对稀有鮈鲫生长抑制最低可见效应浓度(LOEC)值分别为20、1.5、100和50 mg·L-1,表明4种PFOS替代品均显示低慢性毒性。急慢性综合分析可知C4和C6三防整理剂相对较安全,可能成为理想的PFOS替代品。 相似文献
198.
One hundred and twenty-five fetuses were identified as having an AVSD with normal venous connections, normal arterial connections and normal cardiac situs on fetal echocardiography. Fetal karyotype was known in 111 of these cases. The relative risk of fetal trisomy 21 at mid-trimester was 107 (95% CI 87–127) times the expected number of cases compared with risk from maternal age alone, and that for trisomy 21,18 or 13 was 95 (95% CI 79–109). This data may be useful in counselling pregnant women about risk of fetal karyotypic abnormality after a diagnosis of fetal AVSD. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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