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281.
Two cases are presented which illustrate the association of elevated maternal serum alpha feteprotein (MSAFP) levels and chorioangiomas. These cases emphasize the importance of ultrasound study of the placenta in MSAFP elevation evaluation. In addition, placentas from pregnancies with otherwise unexplained MSAFP elevations should be submitted for pathologic study. A definitive retrospective diagnosis may thus be provided. 相似文献
282.
We assayed maternal serum samples from 134 black and 268 white women from 16 to 18 weeks of gestation for intact human chorionic gonadotropin (hCG), and unconjugated oestriol (uE3). Serum from women with high ( ⩾ 2·5 MOMs) or low (risk for Down syndrome ⩾ 1/365) maternal serum alpha-fetoprotein (MSAFP) levels were excluded. After correcting for maternal weight, we found that median hCG levels were 16 per cent higher in black women but uE3 levels were not significantly different. These results confirm three other studies for hCG and one study for uE3. Corrections are recommended for both maternal serum hCG and AFP before calculating the risk for Down syndrome in black women. 相似文献
283.
284.
Eight patients were referred for prenatal diagnosis for suspected fetal cytomegalovirus infection (CMV): six for documented first-trimester infection and two for abnormal ultrasound evaluation suggestive of fetal infection. Three methods of diagnosis were employed: (1) amniotic fluid viral cultures and CMV-specific IgM in fetal serum; (2) amniotic fluid cultures and detection by polymerase chain reaction amplification of CMV-specific DNA in chorionic villi; and (3) detection of CMV-specific DNA in villus samples only. Amniotic fluid cultures detected all cases of infection, but CMV-specific IgM was not a reliable indicator of infection in any case. DNA analysis correlated well with both culture results and clinical outcome. 相似文献
285.
286.
This study evaluates the long-term pulmonary complications of 25 children from a prospective, matched-control, pilot study evaluating short-term complications of early (11–14 weeks' gestation) versus traditional (15 weeks' gestation and later) genetic amniocentesis. Five children in the early amniocentesis group were found to have various respiratory difficulties, a morbidity rate comparable to that of paediatric patients in the general population. These data identify the need for larger, multicentre trials. 相似文献
287.
Johannes M. Baveco Anne-Kari Bergjord Jarle W. Bjerke Magda E. Chudzińska Loïc Pellissier Caroline E. Simonsen Jesper Madsen Ingunn M. Tombre Bart A. Nolet 《Ambio》2017,46(2):210-223
Many goose species feed on agricultural land, and with growing goose numbers, conflicts with agriculture are increasing. One possible solution is to designate refuge areas where farmers are paid to leave geese undisturbed. Here, we present a generic modelling tool that can be used to designate the best locations for refuges and to gauge the area needed to accommodate the geese. With a species distribution model, locations are ranked according to goose suitability. The size of the area to be designated as refuge can be chosen by including more or less suitable locations. A resource depletion model is then used to estimate whether enough resources are available within the designated refuge to accommodate all geese, taking into account the dynamics of food resources, including depletion by geese. We illustrate this with the management scheme for pink-footed goose Anser brachyrhynchus implemented in Norway. Here, all geese can be accommodated, but damage levels appear to depend on weather, land use and refuge size. 相似文献
288.
Most European goose populations have increased exponentially, and this has increasingly brought them into conflict with human activities. To manage this conflict, we used multi-criteria decision analysis to help set population targets for a super-abundant population of greylag geese (Anser anser). We relied on expert elicitation to assess the consequences of varying goose abundance on nine ecological, economic, and societal objectives. Representatives from national governments and from non-governmental organizations then weighted the objectives based on their perceived relative importance, and we used a consensus-convergence model to reach stakeholder agreement on the tradeoffs among objectives. The preferred population targets for two management units represent about a 20% reduction from current abundances, which from a management perspective would require considerable effort above and beyond current population-control measures. We believe that multi-criteria decision analysis can provide a systematic and transparent framework for building consensus among diverse stakeholders in a wide array of human-wildlife conflicts. 相似文献
289.
Kathrine Hauge Madsen Peter Sandøe 《Journal of Agricultural and Environmental Ethics》2001,14(2):161-168
Risk assessment studies of herbicide resistant sugarbeet have revealed no risks to human health or the environment.Indeed it appears that commercial growth of this crop mightsecure benefits such as decreased pesticide use and increasedbiodiversity. However, widespread resistance to GM crops such asherbicide resistant sugar beet still persists in Europe. It isargued that this is not just because people do not know therelevant facts. Rather it is because popular resistance to GMfood is driven in part by concerns other than the fear ofnarrowly defined risks to health and the environment. These otherconcerns include an aversion to commercial monopoly and anegative view of pesticide use in general. Herbicide resistantsugar beet may also be perceived as a ``Trojan horse,' i.e., acrop whose licensing would create a precedent and make it morelikely that other, less environmentally friendly, crops will beapproved within the current strictly technical and science-basedrisk assessment procedures. To meet these public concerns, a kindof technology assessment reflecting factors such as benefits andconsumer choice is called for. 相似文献
290.
A cytogenetic survey and follow-up studies were made of 14 cases with supernumerary marker chromosomes, identified among 12 699 prenatal samples, investigated at our institution over a 10-year period from 1980 to 1990. FISH (fluorescence in situ hybridization) techniques were employed to identify the chromosomal origin of the marker chromosomes. Five cases were familial, all derived from acrocentric chromosomes, and all without apparent phenotypic effects in the children. Nine cases represented de novo aberrations. In two cases (one with a marker from chromosome 14 or 22, the other with a ring-like marker derived from chromosome 17), the pregnancies continued and apparently normal babies were delivered at term, but the child with a marker derived from chromosome 17 showed slight psychomotor retardation at 2 years of age. All other pregnancies with de novo markers were terminated. In three cases, significant abnormalities were found at autopsy. One of these had an isochromosome 12p and the phenotype was consistent with Pallister-Killian syndrome. In conclusion, marker chromosome identification, as well as clinical follow-up, is essential for the purpose of improving genetic counselling. 相似文献