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51.
Marcel Bachstez Ricardo J. Bustamente E. 《Plant foods for human nutrition (Dordrecht, Netherlands)》1954,1(4):372-374
Zusammenfassung Es werden die Charakteristiken und die Zusammensetzung des aus den Samen von Trichilia Specos (Napahuitl) gewonnenen Oels bestimmt.cf. Tesis, Universidad Nacional Autonoma de Mexico, 1946.Vorhergehende Mitteilungen erschienen in Ciencia, Mexico. 相似文献
52.
Spatial patterns of fire occurrence in Catalonia,NE, Spain 总被引:2,自引:0,他引:2
In this paper, we analyse spatial patterns of fire occurrence in Catalonia (NE Spain) during 1975–98. Fire scar maps, discriminated by means of 30–60 m resolution remote sensing imagery, have been used as a source of fire occurrence. We employ several visual or analytical approaches to interpret fire occurrence in this region, such as those of Minnich and Chou (1997), Ricotta et al. (2001) or Krummel et al. (1987). Crucial spatial patterns such as fire size distribution, fire frequency distribution, spots and residual vegetation islands are documented. In addition, several geographical layers were overlaid with burned area maps in order to determine interactions between fire occurrence and environmental parameters such as altitude, slope, solar radiation, and burned land cover. Assuming that fire occurrence is well determined by such a posteriori empirical factors we detect areas most prone to fire in this region and aim to enhance the local forest management and conservation plans. 相似文献
53.
54.
Influence of cover crops on potential nitrogen availability to succeeding crops in a Southern Piedmont soil 总被引:1,自引:0,他引:1
Harry H. Schomberg Dinku M. Endale Ademir Calegari Ricardo Peixoto Mário Miyazawa Miguel L. Cabrera 《Biology and Fertility of Soils》2006,42(4):299-307
Winter cover crops are essential in conservation tillage systems to protect soils from erosion and for improving soil productivity.
Black oat (Avena strigosa Schreb) and oilseed radish (Raphanus sativus L.) could be useful cover crops in the southeastern USA, but successful adoption requires understanding their influence on
N availability in conservation tillage systems. Black oat and oilseed radish were compared to crimson clover (Trifolium incarnatum L.) and rye (Secale cereale L.) for biomass production and effects on N mineralization during the summer crop growing season from fall 1998 through summer
2002 near Watkinsville, GA. Rye produced 40 to 60% more biomass, although N contents were less than the other cover crops.
Oilseed radish and black oat N contents were similar to crimson clover. Black oat, oilseed radish, and crimson clover C/N
ratios were less than 30, whereas rye averaged 39. Amount of N mineralized in 90 days (N
min90) measured with in situ soil cores was 1.3 to 2.2 times greater following black oat, crimson clover, and oilseed radish than
following rye. No differences in N
min90 were found between black oats, crimson clover, and oilseed radish in 1999 and 2000. The amount of potentially mineralizable
N (N
0) was not different due to cover crop, but was 1.5 times greater in 2000 and 2002 than in 1999. The rate of N mineralization
(k) was 20 to 50% slower following rye than the other three cover crops. Black oat and oilseed radish biomass production and
soil N mineralization dynamics were more similar to crimson clover than to rye, which indicates that they could be used as
cover crops in the southeast without significant changes in N recommendations for most crops.
相似文献
Harry H. SchombergEmail: |
55.
De la Mora A Trigo F Jaramillo L Garfias Y Solórzano C Agundis C Pereyra A Lascurain R Zenteno E Suárez-Güemes F 《Veterinary immunology and immunopathology》2006,113(1-2):148-156
In this work we identified specific bovine leukocytes that were bound by the Mannheimia haemolytica adhesin molecule (MhA) and the biological effect on the leukocytes. Histochemical staining and flow cytometry showed that MhA bind neutrophils (90%) and monocytes (5%). MhA induced an oxidative response in purified neutrophils; this effect was 1.5-fold higher than the effect observed with control cells activated with Zymosan. Cellular binding by MhA was inhibited with GlcNAc and its oligomers, as well as by glycoproteins containing tri- and tetra-antennary N-glycosydically linked glycans. MhA-induced oxidative burst was significantly inhibited by GlcNAc, iodoacetamide, superoxide dismutase, and piroxicam (p<0.05). Our findings suggest that among bovine leukocytes, neutrophils are the main target for MhA, inducing production of oxidative radicals by non-opsonic mechanism that seem to play an important role in tissue damage during mannheimiosis. 相似文献
56.
Evaluation of antiviral activity of phenolic compounds and derivatives against rabies virus 总被引:1,自引:0,他引:1
Chávez JH Leal PC Yunes RA Nunes RJ Barardi CR Pinto AR Simões CM Zanetti CR 《Veterinary microbiology》2006,116(1-3):53-59
Human rabies is a viral disease with a great impact on public health, mainly on account of its fatal course in the majority of cases. Despite the well-established prophylaxis by immunization, rabies is believed to be responsible for 40,000-70,000 human deaths per year, mostly in endemic areas. Palliative support and experimental protocols to avoid death have been employed with no expressive results, with the exception of a recent human case of recovery from rabies. No antiviral drugs are currently available to fight against this infection. In combination with the prophylaxis, an antiviral drug would be useful for human rabies treatment, providing enhanced protection against the encephalitis caused by the virus. Phenolic compounds are derived from the secondary plant metabolism, although they can also be obtained by synthetic processes. Many studies have shown a great range of pharmacological effects for these substances, including vasodilatation, antiallergenic, antiinflammatory and antiviral properties, among others. In this study, the potential in-vitro anti-rabies activity of 24 synthetic phenolic compounds was evaluated using McCoy cells and PV rabies strain. The cytotoxicity (CC50) was assayed by the MTT method and the antiviral activity (IC50) was estimated by the inhibition of viral cytopathic effects. Isoprinosine and ketamine were used as positive controls. The tested compounds showed selectivity indices (SI=CC50/IC50) ranging from 1.0 to 3.9. Six phenolic compounds failed to inhibit the cytopathic effect to any degree, and four showed SI > or = 3.0. According to these results, some probable structure-activity relationships are suggested. It was observed that the presence of free hydroxyl and ether groups influenced the anti-rabies activity. However, additional studies are required to establish these relationships. 相似文献
57.
Alba Valéria da Silva Pereira Ricardo Brainer Martins Sami Jorge Michereff Marcelo Bezerra da Silva Marcos Paz Saraiva Camara 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(4):489-498
Stem rot caused by Lasiodiplodia theobromae is an important postharvest disease of papaya in Brazil, responsible for reducing the quality and quantity of fruits. Fungicide
use is one of the main disease management measures. However, there are no estimates available of pathogen sensitivity to commonly
employed fungicides. Therefore, the EC50 from 120 isolates of L. theobromae from northeastern Brazil, representative of six populations of the pathogen, was estimated in vitro for fungicides of the
methyl benzimidazole carbamates—MBC (benomyl and thiabendazole) and demethylation-inhibiting—DMI (imazalil, prochloraz, tebuconazole)
groups. Mycelial growth on fungicide-free media and virulence on papaya fruits of the MBC-sensitive and non-sensitive isolates
were compared. For MBCs, 8.4% of isolates were non-sensitive to fungicides. For the remaining 91.6%, the mean EC50 ranged from 0.002 to 0.13 μg ml−1 and 0.36 to 1.27 μg ml−1 for benomyl and thiabendazole, respectively. For DMIs, the mean EC50 range for imazalil was 0.001 to 2.27 μg ml−1, 0.04 to 1.75 μg ml−1 for prochloraz, and 0.14 to 4.05 μg ml−1 for tebuconazole. The EC50 values of non-sensitive isolates were significantly (P≤0.05) higher those for the sensitive isolates for each of the DMI fungicides. Differences (P≤0.05) were found in the levels of sensitivity to DMI fungicides among the isolate populations associated with orchards. The
populations from two orchards were less sensitive to DMIs. No solid evidence was found for fitness costs relating to MBC non-sensitive
isolates because mycelial growth in fungicide-free media and virulence on papaya fruits were similar to those of sensitive
isolates. 相似文献
58.
59.
Paulo Ricardo Gherardi Hein José Tarcísio Lima Joseph Gril Ant?nio Marcos Rosado Lo?c Brancheriau 《Wood Science and Technology》2012,46(4):621-635
The aim of this study was to establish the relationship between the stiffness of scantlings, approaching structural size materials, and small specimens of 6-year-old Eucalyptus urophylla?×?grandis wood using a resonance technique. The correlation between the elastic modulus (E) of the scantlings in longitudinal vibration and small specimens in flexural vibration was r?=?75 when comparing the scantling values with the averaged values of the specimens per scantling. However, when the E of each single specimen was compared with its respective scantling, the coefficient of correlation decreased to r?=?0.64 in the longitudinal tests and r?=?0.61 in the flexural tests. A roughly linear correlation (r?=?0.59) between specific modulus and loss tangent was obtained for the small specimens of Eucalyptus. In short, the resonance technique rapidly provided a large, accurate data set of mechanical wood properties as required for high-throughput phenotyping in recent genetic studies. 相似文献
60.
Manzano-Román R Díaz-Martín V Oleaga A Siles-Lucas M Pérez-Sánchez R 《Veterinary parasitology》2012,185(2-4):248-259
Subolesin/akirin is a well characterized protective antigen highly conserved across vector species and thus potentially useful for the development of a broad-spectrum vaccine for the control of arthropod infestations including hard ticks, mosquitoes, sand flies and the poultry red mite Dermanyssus gallinae. Soft ticks could be also targeted by this vaccine if proved that the soft tick subolesin orthologs are conserved and induce protective immune responses too. However, to date no soft tick subolesin orthologs have been fully characterized nor tested as recombinant antigens in vaccination trials. The objectives of the present work were to clone and characterize the subolesin orthologs from two important vector species of soft ticks as Ornithodoros erraticus and O. moubata, to evaluate the effect of subolesin gene silencing by RNAi, and to test the protective value of the recombinant antigens in vaccination trials. The obtained results demonstrate that both soft tick subolesins are highly conserved showing more than 69% and 74% identity with those of hard ticks in their nucleotide and amino acid sequences, respectively. Additionally, we demonstrate that both soft ticks possess fully operative RNAi machinery, and that subolesin gene silencing by dsRNA injection inhibits oviposition indicating the involvement of subolesin in tick reproduction. Finally, vaccination with the recombinant soft tick subolesins induced a partial protective effect resulting in the reduction of the oviposition rate. These preliminary results encourage further studies on the use of recombinant subolesins as vaccines for the control of soft tick infestations, either alone or in combination with other specific molecules. 相似文献