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11.
The capacity for binding dimethyl d-tubocurarine-C(14) was studied in isolated nerve-ending membranes from cerebral cortex and myelin. After treatment of the membrane with organic solvents most of the radioactivity was recovered in the extract. Preliminary evidence indicates that dimethyl d-tubocurarine-C(14) is not bound to lipids or glycolipids. While the proteolipids of myelin have a low binding capacity, the results obtained with the nerve-ending membranes rich in acetylcholinesterase suggest that the cholinergic receptor may be a special type of proteolipid. 相似文献
12.
Differences in alpha and beta bat diversity among montane rainforest and five shaded coffee plantations under different management regimes, as well as some environmental factors and vegetation parameters influencing bat richness, were evaluated for the first time in southeastern Chiapas, Mexico. In each site, bats were captured every 2 months from March 2004 to July 2005, with six mist-nets, during two nights, using the capture-recapture method. We captured 2970 individuals of 43 bat species. Montane rainforest had the greatest alpha diversity (H′ = 2.681; n = 37), whereas alpha diversity was similar among coffee plantations (H′ = 2.229-2.364; n = 23-26). The number of frugivorous and nectarivorous species was similar among the sites; the greatest exchange in species composition (beta diversity) occurred for insectivorous bats, which reduce their number in coffee plantations as pesticides are incorporated. Bat richness species was significantly related to the number of vegetation strata, height, and cover of trees. We suggest that coffee plantations could act as corridors, facilitating connection among different elements of the landscape in the Sierra Madre de Chiapas for some frugivorous and nectarivorous bats. 相似文献
13.
Perea-Ganchou F Soto Belloso E González Stagnaro C Soto Castillo G Hernández Fonseca H 《Tropical animal health and production》2005,37(7):559-572
To determine the relationship between first service conception rate (FSC) and the postpartum period (PP), 6160 calvings from
2250 crossbred dual-purpose cows were analysed. The effects of breed predominance (BT: Bos taurus and BI: Bos indicus), season of service (dry, intermediate and humid), parity (1 or 2 and more), agroecological region (Sub-humid and Dry Tropical
Forest) and milk production were studied. The postpartum period was grouped according to the calving–first service interval
as G1 ≤ 60 days (n = 1889); G2 > 60 ≤ 90 days (n = 1436); G3 > 90 ≤ 120 days (n = 1030); and G4 > 120 days (n = 1805). Data were analysed by chi-squared test. The overall mean for FSC was 58.2% and was lower in G1 (p < 0.01). All PP showed a breed effect on FSC, with mean values of 61.6% and 53.3% for BI and BT, respectively. Season of
service also affected FSC, which was significantly lower during the humid period: 51.2% versus 57.4% and 61.5% for the intermediate
and dry periods (p < 0.01), respectively. Parity and environmental effects were not observed on FSC. Levels of milk yield did influence the
FSC, which decreased from 66.7% and 61.0% for milk yields of < 1500 kg and between 1501 and 2000 kg to 46.0% in milk yields
> 2000 kg (p < 0.01). 相似文献
14.
Perea F Soto E Hernández H González D Palomares R De Ondiz A González C 《Tropical animal health and production》2006,38(4):353-363
The aim of this study was to examine the monthly variation of the first service conception (FSC) and oestrus frequency (OF)
from 8308 artificial inseminations (AI) of 2960 crossbred dual-purpose cows on three commercial farms with improved management
located in the Maracaibo Lake Basin, Venezuela. The effects of month of the year, agroecological area (from dry tropical forest
to sub-humid tropical forest on the three farms), predominant breed (BT, Bos taurus; BI, Bos indicus), and season (December–April}; May–August; and September–November) were considered. Data were analysed using logistic regression
(FSC) and GLM (OF) from SAS. The mean FSC was 55.4% overall and 48.7%, 57.0% and 58.3% for farms A, B and C, respectively
(p < 0.01). Within the three agroecological areas (farms A, B and C), the FSC was highest during the cooler and drier months
of the year (season 1), while the lowest FSC was obtained during the months of highest rainfall and humidity (season 3) (53.3%
vs 37.4%; 58.5% vs 49.0% and 63.0% vs 52.3% on farms A, B, C, respectively; p < 0.01). In the three studied farms, OF was
higher during the first 4 months of the year; with a diminishing trend towards the end of the year (p % 0.05). In general,
BI cows had a higher FSC than BT cows, especially during the second half of the year, when environmental conditions were characterized
by higher rainfall and humidity with lower wind velocity (58.8%a 55.5%b and 46.4%c in season 1, 2 and 3 respectively; a, b, c p < 0.01). 相似文献
15.
María Dolores Romero-de Soto Patricia García-Salas Salvador Fernández-Arroyo Antonio Segura-Carretero Francisco Fernández-Campos Beatriz Clares-Naveros 《Plant foods for human nutrition (Dordrecht, Netherlands)》2013,68(2):200-206
A dehydrated vegetables mixture loaded in four pharmaceutical dosage forms as powder, effervescent granulate, sugar granulate and gumdrops were investigated for their antioxidant capacity using 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging capacity assay, oxygen radical absorbance capacity assay and ferric reducing antioxidant potential assay. Total phenolic content of dehydrated vegetables powder mixture was also measured by the Folin-Ciocalteu method, so as to evaluate its contribution to their total antioxidant function. The effect of different temperatures on stability of these systems after 90 days storage was also evaluated. These formulations presented strong antioxidant properties and high phenolic content (279 mg gallic acid equivalent/g of sample) and thus could be potential rich sources of natural antioxidants. Antioxidant properties differed significantly among selected formulations (p?<?0.05). Generally, the losses were lower in samples stored under refrigeration. To interpret the antioxidant properties a kinetic approach was performed. Degradation kinetics for the phenolic content and antioxidant capacity followed a zero-order function. Effervescent granulate was the formulation which underwent faster degradation. Contrary, sugar granulate and gumdrops were much more slowly. Time required to halve the initial amount of phenolic compounds was 589?±?45 days for samples stored at 4?º C, and 312?±?16 days for samples stored at room temperature. These developed dosage forms are new and innovative approach for vegetable intakes in population with special requirements providing an improvement in the administration of vegetables and fruits. 相似文献
16.
17.
Sonia A. Soto‐Rodriguez Rodolfo Lozano‐Olvera Daniel A. Palacios‐Gonzalez Carmen Bolan‐Mejia Karla G. Rendon‐Aguilar 《Journal of the World Aquaculture Society》2019,50(5):1002-1015
The phenotypic characteristics and growth kinetics at several temperatures, salinities, and pH values of three Vibrio parahaemolyticus (Vp) strains with different virulence and one nonpathogenic strain were evaluated. Independent of the virulence of the strain, a high metabolic diversity was found, which yielded different colored phenotypes on the CHROMagar? Vibrio. All strains were resistant to ampicillin and carbenicillin, and Vp AHPND+ organisms were the most sensitive to enrofloxacin. The exponential growth of Vp strains started at 1–2 hr of incubation, although no relationship was observed between the bacterial density and degree of virulence. Moreover, the growth of the most virulent strain was independent of the nutrients in the incubation media during the initial hour postinoculation. No strain grew at 4°C in 0% NaCl and pH 4, but only Vp AHPND+ grew at 44°C. For all strains, the lag phase was proportional to the NaCl concentration, and the growth was better at pH 8–9. However, the Vp AHPND? strain displayed a greater variability, was more sensitive to extreme conditions, and showed a lag phase of 9 hr independent of the pH. 相似文献
18.
19.
Felipe Pierezan Khalid Shahin Taylor I. Heckman June Ang Barbara A. Byrne Esteban Soto 《Journal of fish diseases》2020,43(4):485-490
Outbreaks of an infectious disease affecting cultured white sturgeon (Acipenser transmontanus) were investigated. Clinical signs included erratic swimming, arching of the back and mortality. Necropsy findings included poorly demarcated yellow to dark-red and friable lesions in the epaxial muscle, ulcerative skin lesions and haemorrhages in the swim bladder and coelomic wall. Histological evaluation revealed areas of necrotizing and heterophilic myositis with aggregates of bacterial cocci. The lumen of blood vessels in the dermis, under ulcerated areas, and in the posterior kidney, was occluded by fibrin thrombi. Aggregates of Gram-positive cocci were observed in the muscle lesions and within the fibrin thrombi in the dermis and kidney. Genetically homogeneous Streptococcus iniae strains were recovered from affected fish from different outbreaks. The isolates shared high degree of similarity at gene locus (gyrB) with previously characterized S. iniae from cultured fish in California, confirming the emergence of this particular strain of S. iniae in US aquaculture. 相似文献
20.
Katherinne Valderrama Manuel Soto‐Dvila Cristopher Segovia Ignacio Vsquez My Dang Javier Santander 《Journal of fish diseases》2019,42(11):1601-1608
Aeromonas salmonicida subsp. salmonicida (hereafter A. salmonicida) is the aetiological agent of furunculosis in marine and freshwater fish. Once A. salmonicida invade the fish host through skin, gut or gills, it spreads and colonizes the head kidney, liver, spleen and brain. A. salmonicida infects leucocytes and exhibits an extracellular phase in the blood of the host; however, it is unknown whether A. salmonicida have an intraerythrocytic phase. Here, we evaluate whether A. salmonicida infects Atlantic salmon (Salmo salar) erythrocytes in vitro and in vivo. A. salmonicida did not kill primary S. salar erythrocytes, even in the presence of high bacterial loads, but A. salmonicida invaded the S. salar erythrocytes in the absence of evident haemolysis. Naïve Atlantic salmon smolts intraperitoneally infected with A. salmonicida showed bacteraemia 5 days post‐infection and the presence of intraerythrocytic A. salmonicida. Our results reveal a novel intraerythrocytic phase during A. salmonicida infection. 相似文献