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排序方式: 共有134条查询结果,搜索用时 7 毫秒
1.
L M Krista E E Pierson G R McDaniel E C Mora J A McGuire S L Bolden L E Miller 《British poultry science》1985,26(3):349-356
Twenty-one male Broad Breasted White turkeys which had been selected for high or low blood pressure were put on an exercise regimen to determine its effect on semen quality. Eleven were from the hypertensive line and 10 from the hypotensive line. Eleven (6 hypertensive and 5 hypotensive) turkeys were placed on an exercise regime of walking (herding) about 1 mile daily for 6 weeks before the experiment began, and then for a further 6 weeks during semen collection. Semen was collected from 11 turkeys on the exercise regime and 10 nonexercised control birds which were kept in their experimental pens during the trial. Both hypertensive and exercised groups showed an improved semen colour score at the first collection period (P less than or equal to 0.09). Only the exercised group showed a significantly (P less than or equal to 0.05) better score than the control group during periods 2 and 3. The hypertensive line showed significantly higher spermatozoa count than the hypotensive line during the first collection period. There was no effect of either exercise or selection for high or low blood pressure on semen volume. 相似文献
2.
R. M. Wallace D. Stanek S. Griese D. Krulak N. M. Vora L. Pacha V. Kan M. Said C. Williams T. H. Burgess S. S. Clausen C. Austin J. Gabel M. Lehman L. N. Finelli G. Selvaggi P. Joyce F. Gordin D. Benator A. Bettano S. Cersovsky C. Blackmore S. V. Jones B. D. Buchanan A. I. Fernandez D. Dinelli K. Agnes A. Clark J. Gill M. Irmler D. Blythe K. Mitchell T. J. Whitman M. J. Zapor S. Zorich C. Witkop P. Jenkins P. Mora D. Droller S. Turner L. Dunn P. Williams C. Richards G. Ewing K. Chapman C. Corbitt T. Girimont R. Franka S. Recuenco J. D. Blanton K. A. Feldman 《Zoonoses and public health》2014,61(8):560-570
This article describes and contrasts the public health response to two human rabies cases: one organ recipient diagnosed within days of symptom onset and the transplant donor who was diagnosed 18 months post‐symptom onset. In response to an organ‐transplant‐related rabies case diagnosed in 2013, organ donor and recipient investigations were conducted by multiple public health agencies. Persons with potential exposure to infectious patient materials were assessed for rabies virus exposure. An exposure investigation was conducted to determine the source of the organ donor's infection. Over 100 persons from more than 20 agencies spent over 2700 h conducting contact investigations in healthcare, military and community settings. The 564 persons assessed include 417 healthcare workers [5.8% recommended for post‐exposure prophylaxis (PEP)], 96 community contacts (15.6% recommended for PEP), 30 autopsy personnel (50% recommended for PEP), and 21 other persons (4.8% recommended for PEP). Donor contacts represented 188 assessed with 20.2% recommended for PEP, compared with 5.6% of 306 recipient contacts recommended for PEP. Human rabies cases result in substantial use of public health and medical resources, especially when diagnosis is delayed. Although rare, clinicians should consider rabies in cases of encephalitis of unexplained aetiology, particularly for cases that may result in organ donation. 相似文献
3.
Jér?me?MathieuEmail author Jean-Pierre?Rossi Michel?Grimaldi Philippe?Mora Patrick?Lavelle Corinne?Rouland 《Biology and Fertility of Soils》2004,40(5):300-305
The influence of three spatially hierarchical factors upon soil macrofauna biodiversity was studied in four pasture plots in eastern Amazonia. The first factor was the local depth of the soil. The second factor was the ground cover type on the soil samples (bare ground, grass tufts, dead trees lying on the ground). The third factor was the dimensions of the grass tufts sampled (size and shape). The effect of each factor upon the morphospecies richness and density of total soil macrofauna was analysed. Detailed results are given for earthworms, termites, ants, beetles and spiders. All factors significantly affected the morphospecies richness and/or density of the soil macrofauna. The type of ground cover had the strongest influence, affecting the total richness and density of the soil macrofauna and of almost all the groups represented. The soil depth affected only the density of the termites and the global morphospecies richness. Interactions between soil depth and ground cover type affected the total macrofauna morphospecies richness and the density of the earthworms. The dimensions of the grass tuft influenced the global morphospecies richness, the morphospecies richness of the ants and the density of the spiders. 相似文献
4.
Mora Campbell 《Agriculture and Human Values》1998,15(1):57-64
The metaphor of the food system,dominant in current research approaches to sustainableagriculture, mirrors the productionist paradigm, whichreduces our relationship to land and food to theproduction and consumption of commodities. Theenactment of the familiar values of nourishment andhospitality is what the goal of sustainableagriculture would amount to in terms of our day to daylived experience. The metaphor of an earthen bowl asa theory of food and agriculture can embody thesevalues such that broader change might be achievedthrough embracing the idea and practice of theories asnourishing and theorizing as hospitable. 相似文献
5.
6.
One of the main biochemical changes that take place during the processing of dry-cured ham is the degradation of the muscle protein fraction, mainly due to the action of muscle enzymes. In the present study, the isolation and tentative identification of 137 fragments from myosin light chain 1 (MLC 1), together with 88 fragments originated from myosin light chain 2 (MLC 2), have been achieved for the first time in Spanish dry-cured ham, proving the intense proteolysis experienced by myofibrillar proteins after dry-cured processing. This study was carried out by use of proteomic technology for peptide identification, and the possible enzymes contributing to the degradation of these proteins were also further discussed. 相似文献
7.
A. Rodríguez Rodríguez C.D. Arbelo J.A. Guerra J.L. Mora J.S. Notario C.M. Armas 《CATENA》2006,66(3):228-235
Soil organic carbon (SOC) plays a key role in the structural stability of soils and in their resistance against erosion. However, and as far as andic soils are concerned, these mechanisms and processes, as well as the influence of the different types of SOC on aggregate stability, are not fully understood. The targets of this paper are: (i) to determine the content and forms of SOC in Andosols under evergreen forest vegetation [laurel (Laurus) and heather (Erica) forest] and (ii) to find out the role of soil organic matter (SOM) in the aggregate stability and in the resistance of Andosols to water erosion. Soil samples have been collected in 80 sites in a 40 km2 area under udic soil moisture regime. In them, fulvic and humic acids, Walkley–Black SOC, pyrophosphate-extractable SOC, Fe and Al, potassium sulphate extractable SOC, dissolved SOC, acid oxalate-extractable Fe, Al and Si, USLE K-factor and aggregate stability have been determined. The Andosols over volcanic ash are Aluandic Andosols (non-allophanic Andosols), whereas over basaltic lava flows are Silandic Andosols (allophanic Andosols). The surface (0–30 cm) samples analyzed contain 9.5–30 kg C m− 2 being significantly higher in allophanic Andosols (p < 0.5). Organic carbon adsorbed onto the mineral fraction (extractable pyrophosphate, Cp) accounts for 35–55% of the total SOC. All samples show a high stability to slaking and raindrop impact, being the first one highly correlated (r = 0.6) with pyrophosphate extractable C (Cp), Fe (Fep), and Al (Alp) in allophanic Andosols, unlike non-allophanic ones. The stability to raindrop impact correlates with pyrophosphate extractable C (Cp) and Fe (Fep) in both types of soils (r = 0.3–0.6, p < 0.05). These findings suggest that the high stability to both slaking and water-drop impact is due to the occurrence of allophane–Fe–OC complexes, rather than to the total OC, and the active Fe and Al forms, generated by the weathering of volcanic materials, constitute an essential constituent responsible for C sequestration and resistance to degradation in these soils. 相似文献
8.
Little is known about the relationship between soil biological function and the physical and chemical characteristics of soil-feeding termite nests in the Lopé tropical rainforest (Gabon). We compared nine soil-feeding termite nests of Cubitermes of different ages (fresh to mature to old) and six surrounding soils that originated from three forests differing with respect to age and vegetative cover according to 14 physical and chemical variables and acid (pH 4) and alkaline (pH 9) phosphatase activities. Physical and chemical variables of the studied samples were influenced by the three factors tested: (1) forest age, (2) termite activity (nest versus soil), (3) termite nest age. Soils from the gallery forest were strongly discriminated from all the other soils studied notably due to their high organic matter contents. All mature nests showed significant increases in K, P, clay and fine silt, pH, and cationic exchange capacity compared to soils. Some nests also had increased amounts of organic matter and larger water retention capacities. Moreover, we observed that with age the termite nests possessed decreased values of these variables from fresh to mature to old. Likewise, phosphatase activities also differed according to the three factors tested. Due to its high organic matter contents, the highest phosphatase activities were noted in the gallery forest. Within each forest, phosphatase activities decreased in mature nests compared to soils and tended to be higher in fresh nests compared to mature nests. These differences might be due to an inhibition by high inorganic P contents, as mature nests were enriched in this element and to the quality of organic matter as nests are built with termite faeces. Termite activity has an important role in influencing physical and chemical variables and phosphatase activities. 相似文献
9.
Cortés C De la Fuente R Blanco J Blanco M Blanco JE Dhabi G Mora A Justel P Contreras A Sánchez A Corrales JC Orden JA 《Veterinary microbiology》2005,110(1-2):67-76
Faecal samples from 222 healthy dairy goats on 12 farms in Spain, as well as bulk tank milk samples of these farms, were screened for the presence of verotoxin-producing Escherichia coli (VTEC) and enteropathogenic E. coli (EPEC). VTEC and EPEC were isolated in 47.7 and 7.7% of the animals, respectively. VTEC were isolated more frequently from adults and replacement animals than from goat kids. In contrast, EPEC were detected more frequently from goat kids than from replacement animals and adults. VTEC or EPEC strains were not detected in the bulk tank milk samples. Although a selective enrichment protocol was used, the serotype O157:H7 was not detected. The most frequent serotypes among the 106 VTEC strains isolated from goats were O5:H-, O76:H19, O126:H8, O146:H21, ONT:H- and ONT:H21. None VTEC strain was eae-positive. The absence of the eae gene in the VTEC strains could indicate that these strains are less virulent for humans that the classical eae-positive enterohaemorrhagic E. coli types. However, 16% of VTEC strains isolated from healthy goats belonged to serotypes associated with haemolytic uraemic syndrome in humans. The ehxA gene was detected in 84.9 and 52.9% of the VTEC and EPEC from goats, respectively. The beta1, theta/gamma2 and zeta were the most frequent intimin types among the 17 EPEC strains studied and the most prevalent serotypes of these strains were O156:H25 and O177:H11. Our data show that in Spain healthy goats are an important reservoir of VTEC and EPEC, and a potential source of infection for humans. 相似文献
10.
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