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351.
锡矿山粉尘的危害与防治 总被引:1,自引:0,他引:1
介绍了锡矿山矿务局粉尘危害的情况和采取的防治措施 ,提醒人们对粉尘危害应重视 相似文献
352.
为查清贵州地氟病与碘缺乏病病源,对这两种地方病区地质环境及食物中氟与碘的含量进行研究.结果表明:高氟燃煤、磷块岩及富氟岩石是产生地氟病的氟源,其致病途径主要是高氟燃煤对室内空气与食物造成氟污染,其次是富氟岩、矿经风化形成富氟土壤,使其上种植的食物含氟高,从而产生氟中毒.碘缺乏病的病源是病区岩石中贫碘,导致土壤、水体及食物中碘低而致病.并探讨了这两种地方病在贵州呈互补性分布,是由氟与碘的地球化学性质相似性及贵州省岩石地层分布的地域性所引起的. 相似文献
353.
宁南霉素防治烟草花叶病的研究 总被引:15,自引:4,他引:15
在我国四川省和云南省进行的总面积901.86hm2多点防治试验、示范结果表明,农用抗生素宁南霉素对烟草花叶病的防治效果为69.4%~95.4%,平均增产效果为26.1%,均优于目前推广防治烟草花叶病的植病灵、菌毒清和83增抗剂,并可使烟叶的内在质量明显提高.在温室内施药间隔3~10d后,人工分别接种烟花叶病毒(TMV)、黄瓜花叶病毒(CMV)和马铃薯Y病毒(PYV),实验表明,宁南霉素对烟花叶病毒(TMV)和黄瓜花叶病毒(CMV)所引起的烟草花叶病的防治效果高达92.9%和90.9%,对马铃薯Y病毒(PYV)引起的烟草花叶病的防治效果达53.8%. 相似文献
354.
蚯蚓粪中拮抗微生物分析 总被引:19,自引:0,他引:19
实验证明,蚯蚓对有机废弃物进行生物降解的产物一蚯蚓粪,在一定程度上能够控制一些蔬菜类植物苗期土传病害的发生.对此现象的一种解释是蚯蚓粪中含有一些拮抗微生物.从以牛粪为饵料生产的蚯蚓粪中分离出两株拮抗活性强、范围广的拮抗微生物并得到鉴定:0103A球孢链霉菌(Streptomyces globisporus)和0104A丁香苷链霉菌(Streptomyces syringini),该菌及其发酵液对多种病原菌的抑菌谱及胚根、盆栽生物测定实验表明:两株拮抗菌在蚯蚓粪对蔬菜苗期病害的控制中起重要作用.表8参17 相似文献
355.
Alexandra L. DeCandia Andrew P. Dobson Bridgett M. vonHoldt 《Conservation biology》2018,32(4):798-807
Pathogens pose serious threats to human health, agricultural investment, and biodiversity conservation through the emergence of zoonoses, spillover to domestic livestock, and epizootic outbreaks. As such, wildlife managers are often tasked with mitigating the negative effects of disease. Yet, parasites form a major component of biodiversity that often persist. This is due to logistical challenges of implementing management strategies and to insufficient understanding of host–parasite dynamics. We advocate for an inclusive understanding of molecular diversity in driving parasite infection and variable host disease states in wildlife systems. More specifically, we examine the roles of genetic, epigenetic, and commensal microbial variation in disease pathogenesis. These include mechanisms underlying parasite virulence and host resistance and tolerance, and the development, regulation, and parasite subversion of immune pathways, among other processes. Case studies of devil facial tumor disease in Tasmanian devils (Sarcophilus harrisii) and chytridiomycosis in globally distributed amphibians exemplify the broad range of questions that can be addressed by examining different facets of molecular diversity. For particularly complex systems, integrative molecular analyses present a promising frontier that can provide critical insights necessary to elucidate disease dynamics operating across scales. These insights enable more accurate risk assessment, reconstruction of transmission pathways, discernment of optimal intervention strategies, and development of more effective and ecologically sound treatments that minimize damage to the host population and environment. Such measures are crucial when mitigating threats posed by wildlife disease to humans, domestic animals, and species of conservation concern. 相似文献
356.
Global insect pollinator declines have prompted habitat restoration efforts, including pollinator-friendly gardening. Gardens can provide nectar and pollen for adult insects and offer reproductive resources, such as nesting sites and caterpillar host plants. We conducted a review and meta-analysis to examine how decisions made by gardeners on plant selection and garden maintenance influence pollinator survival, abundance, and diversity. We also considered characteristics of surrounding landscapes and the impacts of pollinator natural enemies. Our results indicated that pollinators responded positively to high plant species diversity, woody vegetation, garden size, and sun exposure and negatively to the separation of garden habitats from natural sites. Within-garden features more strongly influenced pollinators than surrounding landscape factors. Growing interest in gardening for pollinators highlights the need to better understand how gardens contribute to pollinator conservation and how some garden characteristics can enhance the attractiveness and usefulness of gardens to pollinators. Further studies examining pollinator reproduction, resource acquisition, and natural enemies in gardens and comparing gardens with other restoration efforts and to natural habitats are needed to increase the value of human-made habitats for pollinators. 相似文献
357.
As apex predators disappear worldwide, there is escalating evidence of their importance in maintaining the integrity and diversity of the ecosystems they inhabit. The largest extant marsupial carnivore, the Tasmanian devil (Sarcophilus harrisii) is threatened with extinction from a transmissible cancer, devil facial tumor disease (DFTD). The disease, first observed in 1996, has led to apparent population declines in excess of 95% in some areas and has spread to more than 80% of their range. We analyzed a long‐term Tasmania‐wide data set derived from wildlife spotlighting surveys to assess the effects of DFTD‐induced devil decline on populations of other mammals and to examine the relative strength of top–down and bottom–up control of mesopredators between 2 regions with different environmental conditions. Collection of the data began >10 years before DFTD was first observed. A decrease in devil populations was immediate across diseased regions following DFTD arrival, and there has been no indication of population recovery. Feral cats (Felis catus) increased in areas where the disease was present the longest, and feral cat occurrence was significantly and negatively associated with devils. The smallest mesopredator, the eastern quoll (Dasyurus viverrinus), declined rapidly following DFTD arrival. This result suggests the species was indirectly protected by devils through the suppression of larger predators. Rainfall deficiency was also a significant predictor of their decline. Environmental variables determined the relative importance of top–down control in the population regulation of mesopredators. In landscapes of low rainfall and relatively higher proportions of agriculture and human settlement, top–down forces were dampened and bottom–up forces had the most effect on mesopredators. For herbivore prey species, there was evidence of population differences after DFTD arrival, but undetected environmental factors had greater effects. The unique opportunity to assess population changes over extensive temporal and spatial scales following apex predator loss further demonstrated their role in structuring ecosystems and of productivity in determining the strength of top–down control. Cascadas Tróficas Después de la Declinación Inducida por Enfermedad de un Depredador Apical, el Demonio de Tasmania 相似文献
358.
PETR CIVIŠ JIRI VOJAR ATTILA HETTYEY ENDRE SÓS RÓBERT DANKOVICS ROBERT JEHLE DITTE G. CHRISTIANSEN FRANCES CLARE MATTHEW C. FISHER TRENTON W. J. GARNER JON BIELBY 《Conservation biology》2014,28(1):213-223
Amphibians are globally threatened, but not all species are affected equally by different threatening processes. This is true for the threat posed by the chytridiomycete fungus (Batrachochytrium dendrobatidis). We compiled a European data set for B. dendrobatidis to analyze the trends of infection in European amphibians. The risk of infection was not randomly distributed geographically or taxonomically across Europe. Within countries with different prevalence, infection was nonrandom in certain amphibian taxa. Brown frogs of the genus Rana were unlikely to be infected, whereas frogs in the families Alytidae and Bombinatoridae were significantly more likely to be infected than predicted by chance. Frogs in the 2 families susceptible to B. dendrobatidis should form the core of attempts to develop spatial surveillance studies of chytridiomycosis in Europe. Ideally, surveys for B. dendrobatidis should be augmented by sampling the widespread genus Pelophylax because this taxon exhibits geographically inconsistent overinfection with B. dendrobatidis and surveillance of it may facilitate recognition of factors causing spatial variability of infection intensity. Several European amphibian taxa were not represented in our data set; however, surveillance of unsampled species should also occur when warranted. Evaluación de Riesgo y Orientación para el Monitoreo de Batrachochytrium dendrobatidis en Europa Mediante la Identificación de la Selectividad Taxonómica de la Infección 相似文献
359.
Thomas J. Simpson Mitsuhiko Koresawa W. Allen Hogge Wolfgang Holzgreve Dr. Mitchell S. Golbus 《黑龙江环境通报》1987,7(9):639-652
A reliable and sensitive microassay for the measurement of liver glucose-6-phosphatase is described. Human fetal liver was assayed for glucose-6-phosphatase activity from 7.5 to 24 weeks of gestation and was found to have a mean activity of 2.11 nmol per min per mg of protein. This was approximately 30 per cent of the postnatal controls assayed by the same method, but there was no evidence of a change in activity during the gestational period examined. If fetal liver tissue can be reliably obtained, it may be possible to determine a deficiency of glucose-6-phosphatase in fetuses who are at risk. 相似文献
360.
Nicola Rizzo Sandro Gabrielli Gianluigi Pilu Antonella Perolo Alfredo Cacciari Remigio Domini Luciano Bovicelli 《黑龙江环境通报》1987,7(2):109-118
Multicystic dysplastic kidney disease (MDKD) is one of the most common congenital renal anomalies. We report 16 consecutive cases of MDKD recognized in the antenatal period by sonography. Diagnosis is usually easy as MDKD has in the vast majority of cases a striking ultrasound appearance including enlargement of the kidney and multiple renal cysts. However, differentiation from obstructive uropathy may be difficult, and we made a total of five erroneous diagnoses. Unilateral MDKD has almost invariably a good prognosis. However, severe life-threatening associated anomalies were found in six cases. Therefore, a detailed survey of fetal anatomy and determination of karyotype are strongly recommended. 相似文献