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291.
We studied a family at risk for atypical TSD in which the index case showed, clinically, a late onset and a gradual psychomotor deterioration and biochemically, a residual hex. A activity in leucocytes. Two prenatal diagnoses of affected fetuses were made in this family, The first one on amniotic cells, the second one on trophoblast biopsy samples. Both of them were confirmed after abortion on cultured cells. Prenatal diagnosis of TSD, even of some atypical forms is possible using trophoblast biopsy, but formal confirmation should be obtained on cultured trophoblasts.  相似文献   
292.
Dutch disease and, more recently, resource curse thesis have been critical issues for development of resource abundant economies. This paper attempts a comparison between Indonesia and Mexico in their policy adjustments to the oil boom with special reference to the Dutch disease. There exists a striking contrast, especially in their fiscal, foreign borrowing, and exchange rate policies, and confirms the conventional understanding that a booming government should be conservative, as was the case in Indonesia, in its macroeconomic management to avoid the Dutch disease. Equally significant, investment use of oil revenues to strengthen the tradable sector is another factor responsible for Indonesian success. Mexico provides a clear-cut example of the resource curse thesis, but Indonesia is an exception.  相似文献   
293.
张颖琦 《安全》2019,40(8):52-55,60
为提高钢铁冶炼厂焦化作业时的职业健康呼吸防护水平、降低焦化作业中致癌性因素对人体的危害,本文分析了焦化生产中危害呼吸系统的主要职业因素,并以国内外职业健康呼吸防护相关标准和规章制度为评估依据,提出了正确选用、使用和维护呼吸防护用品的方法。相关成果可为相关行业提供指导和借鉴。  相似文献   
294.
The functioning of two foci of helminth diseases caused by trematodes Apophallus muehlingi and Rossicotrema donicum has been studied in the Volga Delta. The origin of these foci is related to the expansion of species ranges of Lithoglyphus snails, intermediate hosts of trematodes. Introduced mammal species, the raccoon dog Nyctereutes procyonoides and American mink Mustela vision, are involved in the circulation of the invasion.  相似文献   
295.
杉木对炭疽病的抗性与苯丙氨酸解氨酶的关系   总被引:11,自引:0,他引:11  
接种前的杉木(Cunninghamia lanceolata)针叶中,苯丙氨酸解氨酶(PAL)比活力与抗感病性之间不呈规律性相关。不同抗病性的杉木接种炭疽菌(Glomerella cingulata)后,PAL比活力均上升,接种5d后,抗病性强的杉木PAL比活力比抗病性弱的杉木高,接种前以及接种后的各个时间段内,木质素含量都是抗病杉木比感病杉木高。绿原酸的含量与杉木的抗病性之间不呈规律性的相关,从绿原酸对炭疽菌菌丝生长影响的测定结果可知,杉木针叶的绿原酸浓度不足以构成对炭疽菌的影响。可见,接种后针叶的PAL比活力以及接种前、后针叶的木质素含量可作为衡量杉木抗病性的指标。图3表2参14  相似文献   
296.
本文论述了现代规模化养殖场疫病综合防制应遵循的原则,并提出了对养殖场疫病的防制具有指导意义的具体的防制技术措施.  相似文献   
297.
In stabilized dunesAmmophila arenaria (marram grass) degenerates due to a process involving soil-borne pathogens and parasites. This leads to exposure of the sand surface so that wind erosion may create blowouts.Ammophila rejuvenates on the edges of the blowouts, where the sand has accumulated. We tested the hypothesis that such rejuvenation of plants may be related to a reduction of the plant-parasitic nematodes and fungal propagules during the process of wind-driven transport. Field measurements in blowouts during storm events indicated that the drifted sand contained relatively low numbers of plant pathogenic fungi and plant-parasitic nematodes. A wind tunnel experiment showed that drifting sand may indeed reduce the numbers of fungi and nematodes. Although most fungi were attached to sand particles, they were also affected by the wind-borne sand movement. Sand that had been deposited by wind was made up of a larger proportion of large-sized particles. In our experiment the relatively small particles were lost during transport. Stirring the soil (part of the forces of natural winds) by mixing for 15 min. with a propeller mixer at 1500 rpm significantly reduced the number of nematodes and fungi. Both sand movement in the wind tunnel and intensive stirring of the sand enhanced the growth ofAmmophila test plants in a bioassay. It was concluded that in wind-blown sand the pathogen inoculum is reduced. Therefore, serious consideration should be given to allowing controlled reactivation of blowouts to rejuvenate decliningAmmophila in stabilized foredunes. Implications for dune management are briefly discussed. Nomenclature: van der Meijden (1990) for vascular plants. Nematodes were identified to the genus level according to Bongers (1988). The allocation of nematodes to feeding groups was according to Yeates et al. (1993). Nomenclature of fungi according to Domsch et al. (1980) was used throughout this study except forFusarium. Species of the latter genus were identified according to Nelson et al. (1983).  相似文献   
298.
Enumeration of Legionella pneumophila in cooling tower water systems   总被引:3,自引:0,他引:3  
Legionella pneumophila, the causative agent of Legionnaires disease, is known to colonise and frequently grow in cooling tower waters. Disease is acquired by inhaling aerosol contaminated by legionellae. Determination of the count of Legionella pneumophila in cooling tower waters may, therefore, be useful for risk assessment. In our survey, 103 water samples from 50 cooling towers were examined over a five-year period to indicate the seasonal distribution and the ecology of L. pneumophila, as regards temperature and pH. L. pneumophila serogroup 1 was found in 44% of the isolated strains, which is primarily responsible for the majority of Legionnaires disease. The large majority of examined towers had levels of L. pneumophila in the high-risk category. These cooling towers have been linked to many outbreaks of Legionnaires disease.  相似文献   
299.
In this article a comprehensive approach for the evaluation of possible health effects in an environmental impact assessment (EIA) is described, illustrated with the example of Amsterdam Airport Schiphol. Unlike many EIAs, we estimated quantitatively the impact of aircraft-related pollution in terms of the number of affected people for aircraft noise annoyance, odour annoyance and hypertension. In addition, an analysis of health registry data on cardiovascular and respiratory diseases and a short survey on annoyance and risk perception were carried out. The scope of a health impact assessment depends on the situation, available knowledge and data, concern in the population about the impact and the number of people concerned. It is important to pay attention to the perception of risks and concerns from all parties involved. Moreover, the results demonstrate that far more people outside the area for which standards apply were affected than inside.  相似文献   
300.
The exploitation of mineral wealth can amplify the problems of the transition economies in three basic ways. First, the rebound of the real exchange rate that characterises a successful transition may be augmented by the capital inflow required to expand mineral production. This can cause both recession in the short-run and lower growth in the medium-term. Second, when the mineral revenues expand, the Dutch Disease effects may intensify the transition-related shrinkage of the non-mining tradeable sector, thereby retarding economic diversification and rendering the economy vulnerable to external shocks. Third, a mineral boom tends to concentrate revenue on the government, which may use it to postpone difficult decisions on economic reform and/or dissipate the revenue due to weak financial markets and inadequate public accountability. Kazakstan, like oil-rich Azerbaijan, is a late reformer and displays evidence of a faster transition rebound than other less resource-rich countries in the CIS do. However, Kazakstan has two advantages over Azerbaijan. First, Kazakstan has a more diversified mineral endowment with which to counter any trend towards single commodity specialization. Second, Kazakstan is making a later start on oil expansion so that it can learn from the experience of Azerbaijan. Priorities for Kazakstan are the continuation of prudent economic policies, the creation of institutions to enhance the transparency of the revenue flows, and the use of environmental accounting to provide a rationale for the deployment of the oil rents.  相似文献   
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