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901.
Congenital nephrosis of the Finnish type (CNF) is rare outside Finland, where the incidence may be as high as 1 in 2000 live births. Neonates with the disorder develop renal failure within the first months of life and without renal transplantation, the prognosis is extremely poor. This case report describes a woman's three pregnancies, two of which were affected with CNF. 相似文献
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Philip DeKoninck Julio Jimenez Francesca M. Russo Ryan Hodges Eduard Gratacós Jan Deprest 《黑龙江环境通报》2014,34(10):977-981
906.
Dr David A. Aitken Gary McCaw Jennifer A. Crossley Esther Berry J. Michael Connor Kevin Spencer James N. Macri 《黑龙江环境通报》1993,13(8):681-689
Alpha-fetoprotein (AFP), unconjugated oestriol (UE3), intact human chorionic gonado-trophin (intHCG), and the free β subunit of chorionic gonadotrophin (FβHCG) were investigated in a series of 21 chromosomally abnormal and 14 open neural tube defect pregnancies ascertained from a series of 14 000 prospectively collected maternal serum samples at 6–14 weeks' gestation. In 16 cases of Down's syndrome, significant reductions were found for AFP (0.65 multiples of the normal median) and UE3 (0.67 MOM). IntHCG levels were unaltered (0.97 MOM) but a significant increase was found for FβHCG (1.96 MOM). Significant correlations were found for AFP and UE3 in the controls and for int HCG and FβHCG in both the control and the Down's syndrome pregnancies. In a group of five trisomy 18 pregnancies, median MOMs were for AFP 0. 71 , for UE3 0. 34 , for intHCG 0. 27 , and for FβHCG 0.15. None of 13 pregnancies with open neural tube defects at 8-13 weeks gestation had elevated maternal serum AFP levels, whereas matched second-trimester samples from the same pregnancies at 16-18 weeks gestation all had significantly elevated AFP levels. Thus, biochemical screening for chromosome abnormalities may be practicable in the first trimester using free β human chorionic gonadotrophin in combination with AFP and maternal age. However, a separate screening protocol using AFP at 15-18 weeks gestation would still be required for effective detection of neural tube defects. 相似文献
907.
Characterizing fish responses to a river restoration over 21 years based on species’ traits 下载免费PDF全文
Stefanie Höckendorff Jonathan D. Tonkin Peter Haase Margret Bunzel‐Drüke Olaf Zimball Matthias Scharf Stefan Stoll 《Conservation biology》2017,31(5):1098-1108
Understanding restoration effectiveness is often impaired by a lack of high‐quality, long‐term monitoring data and, to date, few researchers have used species’ trait information to gain insight into the processes that drive the reaction of fish communities to restoration. We examined fish‐community responses with a highly resolved data set from 21 consecutive years of electrofishing (4 years prerestoration and 17 years postrestoration) at multiple restored and unrestored reaches from a river restoration project on the Lippe River, Germany. Fish abundance peaked in the third year after the restoration; abundance was 6 times higher than before the restoration. After 5–7 years, species richness and abundance stabilized at 2 and 3.5 times higher levels relative to the prerestoration level, respectively. However, interannual variability of species richness and abundance remained considerable, illustrating the challenge of reliably assessing restoration outcomes based on data from individual samplings, especially in the first years following restoration. Life‐history and reproduction‐related traits best explained differences in species’ responses to restoration. Opportunistic short‐lived species with early female maturity and multiple spawning runs per year exhibited the strongest increase in abundance, which reflected their ability to rapidly colonize new habitats. These often small‐bodied and fusiform fishes typically live in dynamic and ephemeral instream and floodplain areas that river‐habitat restorations often aim to create, and in this case their increases in abundance indicated successful restoration. Our results suggest that a greater consideration of species’ traits may enhance the causal understanding of community processes and the coupling of restoration to functional ecology. Trait‐based assessments of restoration outcomes would furthermore allow for easier transfer of knowledge across biogeographic borders than studies based on taxonomy. 相似文献
908.
Rachael Martin Kim Dowling Dora C. Pearce Singarayer Florentine Stafford McKnight Eduard Stelcer David D. Cohen Attila Stopic John W. Bennett 《Environmental geochemistry and health》2017,39(3):549-563
Mine wastes and tailings are considered hazardous to human health because of their potential to generate large quantities of highly toxic emissions of particulate matter (PM). Human exposure to As and other trace metals in PM may occur via inhalation of airborne particulates or through ingestion of contaminated dust. This study describes a laboratory-based method for extracting PM2.5–10 (coarse) and PM2.5 (fine) particles from As-rich mine waste samples collected from an historical gold mining region in regional, Victoria, Australia. We also report on the trace metal and metalloid content of the coarse and fine fraction, with an emphasis on As as an element of potential concern. Laser diffraction analysis showed that the proportions of coarse and fine particles in the bulk samples ranged between 3.4–26.6 and 0.6–7.6 %, respectively. Arsenic concentrations were greater in the fine fraction (1680–26,100 mg kg?1) compared with the coarse fraction (1210–22,000 mg kg?1), and Co, Fe, Mn, Ni, Sb and Zn were found to be present in the fine fraction at levels around twice those occurring in the coarse. These results are of particular concern given that fine particles can accumulate in the human respiratory system. Our study demonstrates that mine wastes may be an important source of metal-enriched PM for mining communities. 相似文献
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910.
Dr Christopher J. Danpure Patricia R. Jennings Richard J. Penketh Pauline J. Wise Penelope J. Cooper Charles H. Rodeck 《黑龙江环境通报》1989,9(4):271-281
Primary hyperoxaluria type 1 (PH1) is caused by a deficiency of the hepatic peroxisomal enzyme alanine: glyoxylate aminotransferase (AGT, EC 2.6.1.44) (Danpure and Jennings, FEBS Lett., 201 , 20–24, 1986). The activity of AGT has been measured in fetal livers of gestational age 14–21 weeks. Activity increases up to 17 weeks and then levels off between 17 and 21 weeks. At this time, the mean AGT activity is about 30 per cent of the mean normal postnatal level. As in adult liver, the AGT enzyme activity and the AGT immunoreactive protein are peroxisomal. Prenatal diagnosis has been performed by measuring AGT enzyme activity and immunoreactive AGT protein on liver biopsies from two fetuses at risk for primary hyperoxaluria type 1. One was unaffected and one was affected. 相似文献