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51.
Kawasaki PM Kano FS Tamekuni K Garcia JL Marana ER Vidotto O Vidotto MC 《Research in veterinary science》2007,83(3):347-354
Anaplasmosis, caused by Anaplasma marginale, results in significant economic losses of cattle in tropical and subtropical regions worldwide. Six major surface proteins (MSPs) were well characterized and designated as MSP1, MSP2, MSP3, MSP4, and MSP5. The objective of this study was to evaluate the humoral immune response of BALB/c mice against the recombinant MSPs, incorporated into immunostimulating complex (ISCOM). The recombinant proteins purified by Ni-NTA columns were incorporated into ISCOM and ISCOMATRIX by the lipid film hydration method. BALB/c mice immunized with ISCOM/rMSPs and ISCOMATRIX/rMSPs vaccines produced whole IgG, IgG1, and IgG2a, in contrast to the negative groups (PBS and ISCOMATRIX adjuvant). All groups that received antigen responded specifically against the rMSPs by Western blotting, showing the rMSP1a (60-105kDa), rMSP1b (100kDa), rMSP4 (47kDa), and rMSP5 (29kDa). Additional studies will have to be performed in cattle to evaluate the humoral and cellular mechanisms of this subunit vaccine and their possible use as protective vaccines against homologous and heterologous strains of A. marginale. 相似文献
52.
Larenza MP Bergadano A Iff I Doherr MG Schatzmann U 《American journal of veterinary research》2005,66(12):2135-2141
OBJECTIVE: To compare the cardiopulmonary effects of anesthesia maintained by continuous infusion of ketamine and propofol with anesthesia maintained by inhalation of sevoflurane in goats undergoing magnetic resonance imaging. ANIMALS: 8 Saanen goats. PROCEDURES: Goats were anesthetized twice (1-month interval) following sedation with midazolam (0.4 mg/kg, IV). Anesthesia was induced via IV administration of ketamine (3 mg/kg) and propofol (1 mg/kg) and maintained with an IV infusion of ketamine (0.03 mg/kg/min) and propofol (0.3 mg/kg/min) and 100% inspired oxygen (K-P treatment) or induced via IV administration of propofol (4 mg/kg) and maintained via inhalation of sevoflurane in oxygen (end-expired concentration, 2.3%; 1X minimum alveolar concentration; SEVO treatment). Cardiopulmonary and blood gas variables were assessed at intervals after induction of anesthesia. RESULTS: Mean +/- SD end-expired sevoflurane was 2.24 +/- 0.2%; ketamine and propofol were infused at rates of 0.03 +/- 0.002 mg/kg/min and 0.29 +/- 0.02 mg/kg/min, respectively. Overall, administration of ketamine and propofol for total IV anesthesia was associated with a degree of immobility and effects on cardiopulmonary parameters that were comparable to those associated with anesthesia maintained by inhalation of sevoflurane. Compared with the K-P treatment group, mean and diastolic blood pressure values in the SEVO treatment group were significantly lower at most or all time points after induction of anesthesia. After both treatments, recovery from anesthesia was good or excellent. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that ketamine-propofol total IV anesthesia in goats breathing 100% oxygen is practical and safe for performance of magnetic resonance imaging procedures. 相似文献
53.
Leonardo Manir Feitosa Lucas Pereira Martins Leandro Augusto de Souza Junior Rosangela Paula Lessa 《水产资源保护:海洋与淡水生态系统》2020,30(5):882-891
- Updated distribution ranges are crucial for conservation status assessments. Comprehensive analyses combining published literature and available data on historical catches and species distribution models (SDMs) are effective tools that could improve the prediction of more realistic scenarios for some species, especially those with limited information available and facing multiple threats.
- The present study aimed at generating an updated distribution for the smalltail shark Carcharhinus porosus, one of the most threatened and understudied shark species of the western Atlantic Ocean. Estimates of the key areas for this species conservation based on the SDMs, and trends in catch probabilities throughout its distribution range are provided.
- Four algorithms (BIOCLIM, Domain, Mahalanobis, and Maximum Entropy) were used to model the distribution of C. porosus and calculate its habitat suitability based on marine environmental variables. To assess historical catch probability trends, we built a generalized linear model from published and grey literature data. This analysis was used to estimate catch probability as an indication of population trends.
- SDMs suggest that the northern coast of South America (NCSA) harbours the most suitable habitats for C. porosus in the world, which was expected given its historically high catch rate in this region. In addition, there was a continuously declining catch probability trend starting in the 1970s. However, the decline was smaller for the NCSA as compared with the Gulf of Mexico and the eastern South America coast.
- Results indicate that the NCSA should be considered the currently most important area in the world for this species conservation. Furthermore, the lack of data throughout Central and South American marine regions hampers the evaluation of extinction risk throughout its updated distribution. Thus, research in these areas is urgently required for a more comprehensive conservation status assessment.
54.
L F Karcher J L Le Net B F Turner T J Reimers B C Tennant 《The Cornell veterinarian》1990,80(2):153-162
An 18-year-old Appaloosa mare was examined because of squamous cell carcinoma of the vulva, anorexia with pronounced weight loss, and hypercalcemia. The tumor had developed rapidly over a period of 3 months and externally extended ventrally involving the perineum and the dorsal aspect of the udder. Necropsy examination demonstrated a large primary squamous cell carcinoma of the vulva, perineum, and mammary gland with metastases to the supramammary, sublumbar, deep inguinal, and mediastinal lymph nodes. No gross renal lesions were observed and, histologically, there was only mild vacuolation of renal tubular epithelium. Based on the normal concentration of serum parathyroid hormone, the absence of evidence of hypervitaminosis D, and normal renal function, a diagnosis was made of hypercalcemia of malignancy or pseudohyperparathyroidism. The mechanism responsible for hypercalcemia was not determined, but the histologic type of the neoplasm and the clinical course suggested possible production of a humoral hypercalcemic factor by the neoplasm, similar to that demonstrated in certain types of human squamous cell carcinoma. 相似文献
55.
56.
María del Mar Montiel‐Rozas Marco Panettieri Paula Madejn Engracia Madejn 《Land Degradation \u0026amp; Development》2016,27(3):620-629
The study of different natural carbon sinks has become especially important because of climate change effects. The restoration of contaminated areas can be an ideal strategy for carbon sequestration. The studied area was affected by toxic Aznalcóllar mine spill in 1998. Restoration process of the contaminated area was based, mainly, on the use of two organic amendments: leonardite (LE) and biosolid compost (BC). The objective of this study was to verify whether the application of these amendments promotes the long‐term carbon sequestration in this soil. Five treatments were established: untreated control, biosolid compost (doses 4 and 2) and leonardite (doses 4 and 2). The addition of amendments implied an improvement in soil quality that was directly related to the amendment dose: decrease in bulk density, increase in pH, higher respiration rates and an improvement in the stratification ratio. Dose‐dependent changes in the molecular composition of soil organic matter were shown by nuclear magnetic resonance analysis. Both amendments promoted carbon retention, although because of the low mineralization rates of soil organic matter in LE treatments, the carbon storage was higher. The dosage effect on the carbon balance was more important in LE treatments, whereas in the BC treatments, the balance was similar for both doses. Our findings suggest that LE4 significantly increased the total organic carbon and it was the most suitable treatment for long‐term carbon storage, because of its molecular composition rich in relatively stable aromatic and lignin‐derived compounds. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
57.
Paula Filomena Martins-Lopes Henrique Guedes-Pinto Olinda Pinto-Carnide John Snape 《Euphytica》2001,121(3):265-271
Barbela is an old Portuguese landrace of wheat that is highly genetically heterogeneous. Different Barbela populations when
subjected to aluminium stress show variable levels of tolerance. In order to study the inheritance of this character, doubled
haploid (DH) lines were developed. These DH were obtained by intergeneric crosses of 14 different lines of Barbela with maize.
During this process the efficiency of the technique was evaluated and suggestions for its improvement were obtained. Several
parameters were studied in the crosses: % of crossability, % of embryos per florets pollinated and % of embryos per seed set.
The different genotypes of Barbela showed significant variation for the parameters analysed. When the reciprocal crosses were
analysed, no differences were found, indicating that cytoplasm differences do not influence the parameters of DH production.
However, different spikelet positions (lower, middle and upper) gave highly significant differences in all parameters analysed.
Highest success frequencies were obtained for pollinated spikelets in the middle of the spike. This can indicate that concentrating
on the middle part of the spike can increase the frequency of DHs obtained using inter generic crosses of wheat with maize.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
58.
Paula Brown 《Asia Pacific viewpoint》2005,46(2):135-142
Abstract: This paper discusses my collaboration with Harold Brookfield in the study of Chimbu land and society. We began in 1958 at the Australian National University and worked together until 1965 in joint fieldwork and writing, and then collaborated occasionally after that. It began both of our professional contributions that continued throughout our professional careers. The work could never have been done by one person, either geographer or anthropologist. Our joint paper of 1990 may be the only multigenerational land study in anthropology/geography. Our long‐term study of the Mintima area is a constant reminder of the hazards of short‐sighted development projections. Brookfield always knew what he wanted to find out, and always constructed original methods of research and analysis. The Chimbu–Mintima maps were redrawn many times with many different measuring methods, new air photography and increasing precision. He always connected any specific study and report of work to general theory and would compare a wide range of related findings in other places. His work is a model of scientific method and its place in geographical theory. 相似文献
59.
Reddy GV Tossavainen P Nerg AM Holopainen JK 《Journal of agricultural and food chemistry》2004,52(13):4185-4191
Cabbage, Brassica oleracea subsp. capitata (cv. Lennox and Rinda), and oilseed rape, Brassica rapa subsp. oleifera (cv. Valo and Tuli), plants were grown under ambient CO(2) (360 ppm) or elevated CO(2) (720 ppm) at 23/18 degrees C and under a photoperiod of 22/2 h light (250 micromol m(-)(2) s(-)(1))/dark regime for up to 5 weeks. Afterward, the performance of the crucifer specialist Plutella xylostella (Lepidoptera: Plutellidae) and the generalist Spodoptera littoralis (Lepidoptera: Noctuidae) on those plants was studied. The mean relative growth rate (RGR) of P. xylostella larvae, feeding on both cultivars of oilseed rape or on the Lennox cultivar of cabbage leaves grown at an elevated CO(2) concentration, was significantly reduced as compared to ambient CO(2). A negative larval growth rate at elevated CO(2) was observed for P. xylostella on both oilseed rape cultivars, but the growth rate was reduced but positive on cabbage. Conversely, the RGR of S. littoralis on either plant species was not affected by CO(2) treatment but was lower on cabbage cv. Rinda than on cv. Lennox. The mortality of the larvae was not affected by CO(2) treatment either. At the same time, elevated CO(2) significantly decreased the concentrations of leaf phytochemical constituents in oilseed rape, i.e., total phenolics and total nitrogen, but not in cabbage. The effect of elevated CO(2) on the leaf glucosinolate concentrations of both plant species was marginal. In addition, the observed significant changes in individual glucosinolate concentrations of oilseed rape leaves were not consistent among cultivars. However, our results demonstrate for the first time quite strong effects of CO(2) enrichment on the larval performance of P. xylostella, which is an important pest of Brassica plants around the world. Further studies are still required to increase our understanding of why elevated CO(2) differently affects the performance of specialist and generalist insect herbivores on Brassica plants. 相似文献
60.
Mata-Haro V Cekic C Martin M Chilton PM Casella CR Mitchell TC 《Science (New York, N.Y.)》2007,316(5831):1628-1632
The inflammatory toxicity of lipopolysaccharide (LPS), a component of bacterial cell walls, is driven by the adaptor proteins myeloid differentiation factor 88 (MyD88) and Toll-interleukin 1 receptor domain-containing adapter inducing interferon-beta (TRIF), which together mediate signaling by the endotoxin receptor Toll-like receptor 4 (TLR4). Monophosphoryl lipid A (MPLA) is a low-toxicity derivative of LPS with useful immunostimulatory properties, which is nearing regulatory approval for use as a human vaccine adjuvant. We report here that, in mice, the low toxicity of MPLA's adjuvant function is associated with a bias toward TRIF signaling, which we suggest is likely caused by the active suppression, rather than passive loss, of proinflammatory activity of this LPS derivative. This finding may have important implications for the development of future vaccine adjuvants. 相似文献