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Karim D. Kalache Roberto Romero Giancarlo Conoscenti Faisal Qureshi Suzanne M. Jacques Tinnakorn Chaiworapongsa Marjorie Treadwell Anthony Johnson 《黑龙江环境通报》2003,23(2):108-110
A case of dilated coronary sinus with persistent left superior vena cava diagnosed at 33 weeks in a fetus with trisomy 18 is reported. The features of this cardiac anomaly on prenatal ultrasonography and its association with trisomy 18 are discussed. Published in 2003 John Wiley & Sons, Ltd. 相似文献
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Incorporating fragmentation and non‐native species into distribution models to inform fluvial fish conservation
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Fluvial fishes face increased imperilment from anthropogenic activities, but the specific factors contributing most to range declines are often poorly understood. For example, the range of the fluvial‐specialist shoal bass (Micropterus cataractae) continues to decrease, yet how perceived threats have contributed to range loss is largely unknown. We used species distribution models to determine which factors contributed most to shoal bass range loss. We estimated a potential distribution based on natural abiotic factors and a series of currently occupied distributions that incorporated variables characterizing land cover, non‐native species, and river fragmentation intensity (no fragmentation, dams only, and dams and large impoundments). We allowed interspecific relationships between non‐native congeners and shoal bass to vary across fragmentation intensities. Results from the potential distribution model estimated shoal bass presence throughout much of their native basin, whereas models of currently occupied distribution showed that range loss increased as fragmentation intensified. Response curves from models of currently occupied distribution indicated a potential interaction between fragmentation intensity and the relationship between shoal bass and non‐native congeners, wherein non‐natives may be favored at the highest fragmentation intensity. Response curves also suggested that >100 km of interconnected, free‐flowing stream fragments were necessary to support shoal bass presence. Model evaluation, including an independent validation, suggested that models had favorable predictive and discriminative abilities. Similar approaches that use readily available, diverse, geospatial data sets may deliver insights into the biology and conservation needs of other fluvial species facing similar threats. 相似文献
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Monika Schlegel Alessandra Baumer Mariluce Riegel Ute Wiedemann Albert Schinzel 《黑龙江环境通报》2002,22(5):418-421
An Erratum has been published for this article in Prenatal Diagnosis 22(11) 2002: 1056. We report a case of maternal isodisomy 10 combined with mosaic partial trisomy 10 (p12.31-q11.1). Chromosome examinations from a CVS sample showed a karyotype 47,XY,+mar/46,XY. The additional marker chromosome which was present in 6/25 interphase nuclei was shown by fluorescence in situ hybridization (FISH) to have been derived from a pericentromeric segment of chromosome 10. DNA analysis was performed from umbilical cord blood from the fetus after termination of the pregnancy at 18 weeks. The results showed that the two structurally normal chromosomes 10 were both of maternal origin, whereas the marker chromosome derived from the father. Autopsy of the fetus revealed hypoplasia of heart, liver, kidneys and suprarenal glands, but, apart from a right bifid ureter, no structural organ abnormalities. This fetus represents the second reported instance of a maternal uniparental disomy (UPD) 10. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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必需脂肪酸及其代谢转化产物的营养生理功能研究进展 总被引:1,自引:0,他引:1
为了开发富含n-3多不饱和脂肪酸(n-3PUFA)这一功能性食品,需要我们更深入地认识n-3和n-6脂肪酸.必需脂肪酸α-亚麻酸和亚油酸分别是n-3和n-6多不饱和脂肪酸的母体,两者及其碳链延长产物是不能相互转化的.n-3和n-6脂肪酸的作用也不能相互替代.作为功能性食品成分的n-3和n-6脂肪酸具有预防心血管疾病、治疗高血脂症、轻度老年痴呆症、降低胆固醇血症的危险等作用.本文主要综述n-3和n-6脂肪酸的特殊作用、n-6和n-3脂肪酸之间的相互关系以及在开发富含n-3PUFA动物产品及食品方面的研究进展,并提出了今后尚待解决的问题. 相似文献
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Nancy Steinberg Warren Shirley Soukup Jennifer L. King Peter St. J. Dignan 《黑龙江环境通报》2001,21(13):1111-1113
A case of prenatally diagnosed non-mosaic trisomy 20 in cells cultured from a chorionic villus sample (CVS)is presented. The term placental karyotype was also non-mosaic trisomy 20. The karyotype of thenewborn was 46,XY/47,XY,+20 in foreskin cultures and in a second skin culture; blood lymphocyte culture was 46,XY. Aside from diffuse, hypopigmentary swirls along the lines of Blaschko observed on hisextremities and trunk, referred to as hypomelanosis of Ito, the patient is clinically normal at 8¾ years ofage. In addition, he is one of the oldest reported cases of mosaic trisomy 20 confirmed after birth forwhich the clinical outcome has been monitored. This case demonstrates that these trisomy 20 findings are compatible with normal psychomotor development and phenotype. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献