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排序方式: 共有249条查询结果,搜索用时 109 毫秒
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Ricardo J. Soares Magalh?es Maria S. Salamat Lydia Leonardo Darren J. Gray Hélène Carabin Kate Halton Donald P. McManus Gail M. Williams Pilarita Rivera Ofelia Saniel Leda Hernandez Laith Yakob Stephen T. McGarvey Archie C. A. Clements 《PLoS neglected tropical diseases》2015,9(9)
BackgroundIn order to increase the efficient allocation of soil-transmitted helminth (STH) disease control resources in the Philippines, we aimed to describe for the first time the spatial variation in the prevalence of A. lumbricoides, T. trichiura and hookworm across the country, quantify the association between the physical environment and spatial variation of STH infection and develop predictive risk maps for each infection.Conclusions/SignificanceThis analysis revealed significant spatial variation in STH infection prevalence within provinces of the Philippines. This suggests that a spatially targeted approach to STH interventions, including mass drug administration, is warranted. When financially possible, additional STH surveys should be prioritized to high-risk areas identified by our study in Luzon. 相似文献
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Marília Lara Peixoto Leda Gonçalves Fernandes Matheus Araújo Cardoso Carvalho Milena Leite de Oliveira André Rodrigues dos Reis 《Biocontrol Science and Technology》2017,27(3):424-432
Agro-ecological diversification may increase natural biodiversity and decrease environmental impacts caused by the intensification of management practices, especially with respect to pest control. This study aimed to evaluate mite populations from surveys in commercial coffee (Coffea arabica) orchards managed in different ways. Four different cropping systems were compared: a conventional system (CS), non-pesticide system (NPS), organic system (OS) and organic agroforestry system (OAS). Mite samples were taken from 24 coffee plantations (n?=?6 for each management strategy). Six leaves per plant were collected from five sampling sites totalling 30 leaves from each plantation. Mites were removed from individual leaves, counted and identified to family level. Amongst the predatory mites, two families were detected; the Phytoseiidae was the most abundant family while the Stigmaeidae, generalist predatory mites, were only found in two management systems (NPS and AOS). Of the two families of phytophagous mites, the family Tenuipalpidae was the most abundant, but rarely found in AOS. The other phytophagous family, Tetranychidae, was less abundant in coffee crops than Tenuipalpidae, but the most abundant phytophagous family in CS. Understanding the relationship between mite populations and management practices can aid in choice of spraying strategies for different coffee management systems. 相似文献
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Carlos Romero F. Oliveira Leda Rita D'A. Faroni Raul Narciso C. Guedes Angelo Pallini 《BioControl》2003,48(5):503-513
Recent reports of the biocontrolpotential of the mite species Acarophenaxlacunatus (Cross & Krantz) (Prostigmata:Acarophenacidae) and the lack of biologicalstudies on this regulatory agent led to thepresent study carried out under laboratoryconditions. The objective of the investigationwas to assess the host range of A. lacunatus,so far only reported as egg parasite ofRhyzopertha dominica (F.) (Coleoptera:Bostrichidae). Four Coleoptera species ofstored cereals were used: R. dominica,Tribolium castaneum (Herbst) (Tenebrionidae),Cryptolestes ferrugineus (Stephens)(Laemophloeidae) and Oryzaephilus surinamensis (L.) (Cucujidae). The highest rates of eggparasitism were observed on R. dominica and T.castaneum, leading to a significant decrease ofpopulations of both species and reduced wheatweight loss. A. lacunatus was also able toparasitize eggs of C. ferrugineus, but not ofO. surinamensis. These results indicate abroader host range of A. lacunatus thaninitially suspected and also strengthen itspossibility of use in integrated pestmanagement programs in storage environments. 相似文献
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Maria Sole Cigoli Francesca Avemaria Stefano De Benedetti Giovanni P. Gesu Lucio Giordano Accorsi Stefano Parmigiani Maria Franca Corona Valeria Capra Andrea Mosca Simona Giovannini Francesca Notturno Fausta Ciccocioppo Lilia Volpi Margherita Estienne Giuseppe De Michele Antonella Antenora Leda Bilo Antonietta Tavoni Nelia Zamponi Enrico Alfei Giovanni Baranello Daria Riva Silvana Penco 《PloS one》2014,9(10)
Cerebral cavernous malformations (CCMs) are vascular abnormalities that may cause seizures, intracerebral haemorrhages, and focal neurological deficits. Familial form shows an autosomal dominant pattern of inheritance with incomplete penetrance and variable clinical expression. Three genes have been identified causing familial CCM: KRIT1/CCM1, MGC4607/CCM2, and PDCD10/CCM3. Aim of this study is to report additional PDCD10/CCM3 families poorly described so far which account for 10-15% of hereditary cerebral cavernous malformations. Our group investigated 87 consecutive Italian affected individuals (i.e. positive Magnetic Resonance Imaging) with multiple/familial CCM through direct sequencing and Multiplex Ligation-Dependent Probe Amplification (MLPA) analysis. We identified mutations in over 97.7% of cases, and PDCD10/CCM3 accounts for 13.1%. PDCD10/CCM3 molecular screening revealed four already known mutations and four novel ones. The mutated patients show an earlier onset of clinical manifestations as compared to CCM1/CCM2 mutated patients. The study of further families carrying mutations in PDCD10/CCM3 may help define a possible correlation between genotype and phenotype; an accurate clinical follow up of the subjects would help define more precisely whether mutations in PDCD10/CCM3 lead to a characteristic phenotype. 相似文献
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Increased trade in non-timber forest products (NTFPs) has been promoted as one possible means to slow tropical deforestation by increasing the economic value of intact forest. A market survey of NTFPs occurring in the Capim River basin in eastern Amazonia, Brazil demonstrated that the reality for many smallholder communities in frontier and remote regions includes chronic transportation difficulties, high variability in fruit production, perishable products and lack of market expertise. In some communities, declining abundance of NTFPs due to logging and fire has resulted in a lack of forest products to even meet subsistence needs. In areas close to cities where transportation is assured and where forest clearing has eroded the natural occurrence of some valuable native NTFPs, smallholders who manage and successfully market native fruit and medicinal species are overcoming these obstacles. In frontier regions undergoing rapid transformation, however, decline in locally used and regionally marketed NTFPs currently pose detrimental consequences for communities. Findings suggest that an overemphasis on NTFP marketing has diverted attention from local livelihood, resource access and subsistence issues. 相似文献
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Lucyna Leda Dieter Korn Abbas Ghaderi Vachik Hairapetian Ulrich Struck Wolf Uwe Reimold 《Facies》2014,60(1):295-325
Permian–Triassic boundary sections in the Julfa (NW Iran) and Abadeh (Central Iran) regions display a succession of three characteristic rock units, (1) the Paratirolites Limestone with the mass extinction horizon at its top, (2) the ‘Boundary Clay’, and (3) the earliest Triassic Elikah Formation with the conodont P–Tr boundary at its base. The carbonate microfacies reveals a facies change, in the sections near Julfa, within the Paratirolites Limestone with an increasing number of intraclasts, Fe–Mn crusts, and biogenic encrustation. A decline in carbonate accumulation occurs towards the top of the unit with a sponge packstone in the sections, and finally resulting in a complete demise of the carbonate factory. The succession of the ‘Boundary Clay’ differs in the two regions; thin horizons of sponge packstone are present in the Julfa region and ‘calcite fans’ of probably inorganic origin in the Abadeh Region. The skeletal carbonate factory of the Late Permian was restored with the deposition of microbial carbonates at the base of the Elikah Formation, where densely laminated bindstone, floatstone with sparry calcite spheres, and oncoid wackestone/floatstone predominate. 相似文献
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Evidence for two waves of induction of DNA enzymes in stimulated human lymphocytes 总被引:5,自引:3,他引:2 下载免费PDF全文
Guido C. F. Pedrali Noy Leda Dalpra Antonia M. Pedrini Giovanni Ciarrocchi Elena Giulotto Fiorella Nuzzo Arturo Falaschi 《Nucleic acids research》1974,1(9):1183-1199
The stimulation of human lymphocytes with phytohaemoagglutinin induces the appearance or increase of several enzymes of DNA metabolism [Pedrini etal., Biochem. Biophys. Res. Comm., 47:1221(1972)]. With long times of stimulation, two phenomena are observed; an increase in the levels of DNA polymerase, of a DNase acting on single-stranded DNA, and of an endonuclease, occurring between the third and fourth day, in parallel with a wave of DNA synthesis;a second wave of increase of the same enzymes and of DNA ligase,occurring between the fifth and eight day when the DNA replication rate, as measured by thymidine-pulses, has decreased to values close to the background. 相似文献