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381.
De Pippo T Donadio C Guida M Petrosino C 《Environmental science and pollution research international》2006,13(3):184-191
Background, Aim and Scope Analysis of the morphological, geological and environmental characteristics of the Sarno River basin has shown the present
degraded condition of the area. Over the past thirty years, the supply of untreated effluent of domestic, agricultural and
industrial origin has ensured the presence of high concentrations of pollutants, including heavy metals. The geological context
of the catchment area has played a major part in determining the current ecological conditions and public health problems:
while human activity has modified the landscape, the natural order has indirectly contributed to increasing the environmental
impact.
Results and Discussion The health situation is precarious as the basin's inhabitants feed on agricultural and animal products, and use polluted
water directly or indirectly. The hazard of contracting degenerative illnesses of the digestive or respiratory apparatus,
bacterial infections or some neoplasia has gradually increased, especially in the last five years. Moreover, polluted basin
waters flowing into the Bay of Naples increase sea water contamination, thereby damaging tourism, public health and degrading
the local littoral quality.
Conclusion The overview presented shows how the environmental state of the Sarno River basin gives considerable cause for concern. The
basin's complex geomorphologic setting has a direct bearing on local environmental and health conditions. The analysis of
the available data demonstrates how the physical aspects of the area are closely linked to the diffusion and concentration
of the pollutants, and how the latter ones have a large influence on the hygienic-sanitary conditions of the local population.
Recommendation and Perspective Specific interventions need to be undertaken to monitor and improve the chemical, physical and microbiological conditions
of water and sediments, especially in light of the geomorphological vulnerability of the river basin. 相似文献
382.
A pregnant woman has two children affected by moderately severe Hb H disease due to compound heterozygosity of South-east Asian deletion and Constant Spring mutation. In her third pregnancy, transabdominal chorionic villus sampling was performed at the tenth gestational week to obtain fetal DNA. The polymerase chain reaction was used for detection of both the South-east Asian deletion and the Constant Spring mutation. Hb H disease was diagnosed in the fetus. After genetic counselling, the couple elected to have the pregnancy terminated. 相似文献
383.
384.
KELSEY J. RIPP MELANIE BERGER JANE CHEN JUSTIN DITTMEIER MAGGIE GOTER STEPHEN T. MCGARVEY ELIZABETH RYAN 《Conservation biology》2013,27(6):1378-1388
At local scales, infectious disease is a common driver of population declines, but globally it is an infrequent contributor to species extinction and endangerment. For species at risk of extinction from disease important questions remain unanswered, including when does disease become a threat to species and does it co‐occur, predictably, with other threats? Using newly compiled data from the International Union for Conservation of Nature (IUCN) Red List, we examined the relative role and co‐occurrence of threats associated with amphibians, birds, and mammals at 6 levels of extinction risk (i.e., Red List status categories: least concern, near threatened, vulnerable, endangered, critically endangered, and extinct in the wild/extinct). We tested the null hypothesis that the proportion of species threatened by disease is the same in all 6 Red List status categories. Our approach revealed a new method for determining when disease most frequently threatens species at risk of extinction. The proportion of species threatened by disease varied significantly between IUCN status categories and linearly increased for amphibians, birds, and all species combined as these taxa move from move from least concern to critically endangered. Disease was infrequently the single contributing threat. However, when a species was negatively affected by a major threat other than disease (e.g., invasive species, land‐use change) that species was more likely to be simultaneously threatened by disease than species that had no other threats. Potential drivers of these trends include ecological factors, clustering of phylogenetically related species in Red List status categories, discovery bias among species at greater risk of extinction, and availability of data. We echo earlier calls for baseline data on the presence of parasites and pathogens in species when they show the first signs of extinction risk and arguably before. La Amenaza de Enfermedades Incrementa a Medida que las Especies se Aproximan a la Extinción 相似文献
385.
The purpose of this paper is to explore the use of computer models, including artificial intelligence systems, in the context of risk assessment and management for wildfowl diseases. In particular, the paper focuses on avian cholera and botulism in U.S. wildfowl, which are a source of continuing concern to the U.S. Fish and Wildlife Service (USFWS). Severe outbreaks occur frequently, and some have been estimated to claim the lives of as many as 300 000 waterfowl. A potentially valuable support to the USFWS would be a set of models that assist in recognizing situations with high risk of an outbreak, assessing the anticipated severity of an outbreak, and advising on possible preventive measures. The USFWS has already initiated development of several potentially useful models. This paper reviews these as well as other related efforts, within the overall context of risk management for avian botulism and cholera. 相似文献
386.
387.
Prenatal diagnosis of Gaucher disease, the most prevalent glycolipid storage disease, is based on a reliable enzyme assay of cells from amniocentesis or chorionic villous samples. However, this method cannot differentiate among the various forms of the disease. This report details four cases of prenatal diagnosis of Gaucher disease, three of which predate the use of molecular diagnosis. DNA mutation analysis to determine the genotype was predictive of the phenotypic status of the fetus and conformed to the genotype of an affected proband where available. 相似文献
388.
The condition of coral reefs in South Florida (2000) using coral disease and bleaching as indicators 总被引:2,自引:0,他引:2
Santavy DL Summers JK Engle VD Harwell LC 《Environmental monitoring and assessment》2005,100(1-3):129-152
The destruction of coral reef habitats has occurred at unprecedented levels during the last three decades. Coral disease and bleaching in the Caribbean and South Florida have caused extensive coral mortality with limited recovery, often coral reefs are being replaced with turf algae. Acroporids were once dominant corals and have diminished to the state where they are being considered as endangered species. Our survey assessed the condition of reef corals throughout South Florida. A probability-based design produced unbiased estimates of the spatial extent of ecological condition, measured as the absence or presence and frequency or prevalence of coral diseases and bleaching intensity over large geographic regions. This approach allowed us to calculate a quantifiable level of uncertainty. Coral condition was estimated for 4100 hectares (ha) (or 41.0 km2) of coral reefs in South Florida, including reefs in the Florida Keys National Marine Sanctuary (FKNMS), New Grounds, Dry Tortugas National Park (DTNP), and Biscayne National Park (BNP). The absence or presence of coral disease, causal coral bleaching, partial bleaching and coral paling were not good indicators of overall coral condition. It was more useful to report the prevalence of anomalies that indicated a compromised condition at both the population and community levels. For example, 79% of the area in South Florida had less than 6% of the coral colonies diseased, whereas only 2.2% (97.15 ha) of the sampled area had a maximum prevalence of 13% diseased coral colonies at any single location. The usefulness of causal bleaching might be more important when considering the prevalence of each of the three different states at a single location. For example, paling was observed over the entire area, whereas bleaching and partial bleaching occurred at 19 and 41% of the area, respectively. An index for coral reef condition might integrate the prevalence and species affected by each bleaching state at individual locations. By establishing these baselines, future surveys can examine changes and trends in the spatial distribution of coral conditions in South Florida and able to score the reefs as to their health status. 相似文献
389.
An investigation on the organic degradation products and selenium in the pathogenesis of Kaschin-Beck disease was carried out. The results demonstrated that the organic degradation products existed in food and drinking water were the pathogens of the KBD; their leading pathological process of cells would be "membrane injury" due to peroxide. As GSH-Px is a selenium contained enzyme, therefore insufficient selenium would be one of the most important conditions to cause KBD. 相似文献
390.
The effect of exposure to crude oil contaminated diet on the blood antioxidant defence system, lipid peroxidation, lipid profile
as well as possible protective roles of vitamins E and C were studied in rabbits. Oxidative stress induction by crude oil
was indicated by significantly (P < 0.05) increased lipid peroxidation and a non-significant (P < 0.05) decrease in superoxide dismutase and catalase activities. A similar pattern was also detected in the lipid profile:
total cholesterol and LDL-cholesterol insignificantly (P < 0.05) increased while HDL-cholesterol and triglyceride significantly decreased relative to rabbits fed normal diet. The
reciprocal relationship between HDL-cholesterol and LDL-cholesterol in addition to compromised antioxidant enzymes could predispose
exposed animals to coronary heart disease. However, pre-treatment of the diet with vitamins C and E exhibited a protective
role on the toxic effect of crude oil on lipid profile, lipid peroxidation as well as antioxidant enzymes. The order of protection
was vitamin E + C > vitamin E > vitamin C. These observations seemed to suggest that the protective role of vitamins C and
E is synergistic. The protective role of the vitamins is probably time-dependent as significant (P < 0.05) restoration of lipid profile as well as antioxidant enzymes activities to control values was effected after four
weeks of exposure. It is therefore suggested that toxic effect of crude oil may be reduced by dietary supplementation of vitamins
C and E. 相似文献