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131.
C. Guillermo Couto José J. Cerón MD Parra Silvi Martínez‐Subiela M. Cristina Lazbik 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(2):219-223
Background: Retired racing Greyhounds are popular as pets. Greyhounds have several differences in physiological values compared with other breeds, including lower serum α‐ and β‐globulin concentrations. We hypothesized that lower acute phase protein (APP) concentrations could contribute to lower α‐ and β‐globulin concentrations in this breed. Objectives: The purpose of this study was to compare serum concentrations of several APPs in Greyhounds with those of other dog breeds. Methods: We measured the serum concentrations of C‐reactive protein (CRP), haptoglobin (Hp), acid‐soluble glycoprotein (ASG), ceruloplasmin (CP), and serum amyloid A (SAA) in 15 clinically healthy retired racing Greyhounds and 11 age‐ and gender‐matched healthy nonGreyhound controls using previously validated methods. Results were compared by Student's t‐tests. Results: The concentration of Hp by both colorimetric and immunoturbidimetric methods was significantly lower in Greyhounds than in nonGreyhound dogs (P=.0009 and .019, respectively). The concentration of ASG was also significantly (P=.007) lower in Greyhounds, but CRP and CP concentrations were not significantly different between groups. SAA concentration was below the detection limit of the method in all dogs. Conclusions: The low serum concentrations of Hp and ASG should be taken into consideration when interpreting APP results in Greyhounds. Because both Hp and some ASG migrate in the α‐globulin fraction, these results may explain the low α‐globulin concentrations in Greyhounds. 相似文献
132.
José Ángel Pulgar Lorenzo Guillermo Riesco Muñoz 《European Journal of Forest Research》2018,137(4):507-515
The laurel (Laurus nobilis L.) is a common species in southern Europe, but the properties of its wood are not well described in the literature and from that perspective any novel information is valuable. Because of that, a group of laurels was felled for the analysis of wood properties on small defect-free specimens (17 trees and 1250 valid specimens). The sampled wood was moderately heavy and unstable. The following mean values were obtained (density at 12% moisture content 699 kg m?3; basic density 566 kg m?3; total volumetric shrinkage 18.0%; volumetric shrinkage coefficient 0.59%). Highly significant inter-tree and intra-tree variation was observed for most of the properties considered. The inter-tree variation was attributed to tree dimensions, being remarkable that volumetric, radial and tangential shrinkage coefficients were significantly related to breast height diameter and slenderness. The trends of these variables suggest that in trees older than those used in the study (24–41 years old) the dimensional stability would increase. As regards the inter-tree variation, a low but highly significant decrease was found for density at highest positions in the tree. Volumetric and linear shrinkage diminish very significantly along the stem. Due to the uniformity of density and the increment of wood dimensional stability along the trunk, the harvesting of the full stem is advisable. 相似文献
133.
134.
Schinella GR Tournier HA Máñez S de Buschiazzo PM Del Carmen Recio M Ríos JL 《Fitoterapia》2007,78(1):1-6
Two flavonoids, gnaphaliin and tiliroside, isolated from Helichrysum italicum, were studied in vitro for their capacity to inhibit Cu(2+)-induced human low density lipoprotein (LDL) and diluted plasma oxidation. LDL oxidation was monitored by conjugated diene, thiobarbituric acid-reactive substances (TBARS) formation and electrophoretic mobility on agarose gel. Gnaphaliin and tiliroside increased the lag-phase for diene conjugate production in a dose-dependent manner. The reduction of TBARS production confirmed the antioxidant activity of gnaphaliin and tiliroside with 50% inhibitory concentration (IC(50)) values of 8.0+/-3.9 microM and 7.0+/-2.6 microM respectively. Furthermore, the flavonoids negated the Cu(2+)-induced increase in electrophoretic mobility of LDL. Antioxidant activity of gnaphaliin and tiliroside was significantly different when diluted plasma was oxidised by adding 1 mM CuSO(4). Although both flavonoids again reduced the TBARS production, tiliroside showed higher activity than gnaphaliin (IC(50)=10.6+/-2.5 microM vs. IC(50)>50 microM). In conclusion, tiliroside and gnaphaliin are antioxidants against in vitro Cu(2+)-induced LDL oxidation in the same order of magnitude compared to that of the reference drug, probucol. 相似文献
135.
Jose Alfredo Gutierrez-Reyes ;Estela Flores-Velazquez ;Guillermo Agustin Reyes-Escalona ;Joaquin BraulioDelgadillo-Alvarez ;Marcela Amalia Mercado-Pezzat ;Eli Tonatiuh Selva-Hernandez ;Alejandro Perera-Ortiz ;Jose Alberto Ordufia-Sumaran ;Cecilia Romero-Torres ;Luis Antonio Jimenez-Zamudio ;Ethel AwildaGarcfa-Latorre Citlatepetl Salinas-Lara 《农业科学与技术》2014,(4):277-290
Mexico is considered by different international organizations as a country where the bovine tuberculosis is an endemic problem. However, there are important and consistent improvements in eradicating the disease by the implementation of government policies and with the livestock organization support. The current situation of the program shows good results regarding decreasing the prevalence, and as a consequence, the risk of this disease for public health and animal health, as well as the improvement in animal production and international and national trade. Today, the bovine tuberculosis distribution is almost known in Mexico. In addition, a series of controls and indicators have been established, which allow maintain consistency and reliability in the data that are managed and analyzed. 相似文献
136.
Plaisance H. Coddeville P. Guillermo R. Roussel I. 《Water, air, and soil pollution》1997,93(1-4):267-284
This article presents the setting-up of a validation procedure, especially adapted to the rainwater samples of the MERA and French WMO-GAW networks. A first study reveals that the ion and conductivity balances, usually used as quality criteria, depend on salinity. The statistical tool or “physico-chemical filter” proposed in this paper, includes two mathematical models based on 97th percentile of the ion and conductivity balances, from the 1991 and 1992 data taken as references. This dynamic validation uses the rejection limits which increase with salinity. Its application shows a significant decrease of the total rejection rate between the first and third year of running. This seems to be due to the improvement in quality of the analytical line. The rejected sample inspection does not reveal apparent bias errors for the filter. This kind of validation seems to be well adapted to screen the samples in a precipitation collection network such as MERA and WMO-GAW. 相似文献
137.
Svetaz L Tapia A López SN Furlán RL Petenatti E Pioli R Schmeda-Hirschmann G Zacchino SA 《Journal of agricultural and food chemistry》2004,52(11):3297-3300
The crude methanolic extract of Zuccagnia punctata was active toward the fungal pathogens of soybean Phomopsis longicolla and Colletotrichum truncatum. Assay guided fractionation led to the isolation of two chalcones, one flavanone and a new caffeoyl ester derivative as the compounds responsible for the antifungal activity. Another new caffeoyl ester derivative was isolated from the antifungal chloroform extract but proved to be inactive against the soybean infecting fungi up to 50 microg/mL 相似文献
138.
Daniel A. Presello Juliana Iglesias Grisela Botta Lana M. Reid Gladys A. Lori Guillermo H. Eyhérabide 《Euphytica》2006,147(3):403-407
Sources of resistance to Fusarium spp. are needed to develop maize hybrids resistant to the accumulation of fungal mycotoxins in the grain. In a search for
resistant germplasm in 1999 and 2000, a set of Argentinian maize populations was evaluated in Ottawa, Canada, for resistance
to ear rots after inoculation with local isolates of Fusarium verticillioides and F. graminearum. Sixteen of these populations, varying in observed resistance levels, were re-evaluated in 2003 and 2004 in Pergamino, Argentina,
using local isolates of the same fungi. Conidial suspensions of each fungal species were inoculated into the silk channel
of primary ears. Disease severity was assessed after physiological maturity using a scale based on the percentage of visibly
infected kernels. Genotype effect was more important than genotype-by-fungal species or genotype-by-fungal species-by-environment
interaction effects. In addition, disease severity levels associated with each fungal species were positively correlated (P < 0.05) (r = 0.90, r = 0.81, r = 0.87 and r = 0.53, in Ottawa 1999 and 2000, and Pergamino 2003 and 2004, respectively). Populations ARZM 01107, ARZM 07138, ARZM 10041,
ARZM 13031, ARZM 16002 and Pora INTA exhibited the highest and most stable resistance to both species. Considering that disease
resistance exhibited low specificity to the environment and to the fungal species in evaluations conducted in a wide range
of environments and with fungal isolates collected from different hemispheres, the most resistant populations are potential
sources of genes for stable resistance to these Fusarium spp. 相似文献
139.
140.
Andrés Rogberg-Muñoz Nadia S. Castillo María E. Zappa Julián A. Crespi Egle E. Villegas-Castagnasso Paula M. Gómez Pilar Peral-García Guillermo Giovambattista 《Reproduction in domestic animals》2020,55(9):1267-1270
Cattle are a monotocous species, despite naturally conceived multiple births are sometimes observed. Although the number of twins has consistently increased, triplet and quadruplet pregnancies represent 0.015% and 0.004% of the total births, respectively. Multiple births are the result of multiple ovulation and/or the spontaneous cleavage of one fertilized oocyte, which is known as monozygotic (MZ) twinning. In cattle, approximately 5% to 14% of all twin births are MZ, and births with more than two MZ calves are extremely rare. Monozygotic animals are genetically identical, and those derived from two or more zygotes are genetically different. Furthermore, the presence of placental vascular anastomosis can result in foetal chimerism. Notwithstanding, animals born as single calves can be chimeras when one of the foetal twins dies undetected in utero. Here, we used DNA testing to study the zygotic condition of an unusual female quadruplet born from a Braford cow bred in a multi-sire natural mating system without hormone stimulation. Two tissues with different embryological origin were sampled to test zygosity and possible chimerism. The results showed an identical genotype, confirming they all originated in an MZ pregnancy and suggesting the lack of chimerism in all animals. The use of MZ twins in breeding and selection systems provides an alternative to the conventional progeny testing. Some works have suggested a genetic background of MZ twins in humans. This female and her daughters could be the founders of a lineage to study the possible inheritance of MZ multiple births in cattle. 相似文献