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排序方式: 共有355条查询结果,搜索用时 10 毫秒
101.
Paula Nagl Gustavo Hallwass Luís H. Tomazoni-Silva Pedro P. Nitschke Anais R. P. Rowedder Astrid Tatiana Romero-Martinez Renato A. M. Silvano 《水产资源保护:海洋与淡水生态系统》2021,31(10):2752-2771
- Frugivorous fish provide often conflicting ecosystem services of seed dispersal and food provisioning in tropical rivers. Fishing may reduce the size and abundance of frugivorous fish, thus affecting their potential as seed dispersers, which could affect the conservation of these fish and of floodplain forests.
- The goal of this study was to assess the influence of co-managed protected areas in the form of extractive reserves (RESEX) and small-scale fisheries on frugivorous fish in the Tapajós and Negro rivers, in the Brazilian Amazon. The study examined whether: (i) frugivorous fish are important for fisheries and selectively caught; and (ii) frugivorous fish abundance, size and fisheries catch per unit of effort are higher inside the RESEX than outside.
- The analyses included fisheries-dependent data (3,753 fish landings) and independent data (12,730 sampled fish) collected in 16 fishing communities (eight for each river). In both rivers, frugivorous fish are among the 10 species caught the most and frugivorous biomass was proportionately higher in landings than in samplings, indicating fisheries selectivity towards these fishes.
- In both rivers, catches of frugivorous fish were higher outside the RESEX than inside. Catch per unit effort and the proportion of frugivores in the catch were higher outside the RESEX in the Tapajós River but did not vary between sites inside and outside the RESEX in the Negro River. Frugivorous fish were larger inside the RESEX in the Negro, but smaller inside the RESEX in the Tapajós.
- The results indicated that the ecosystem services of seed dispersal and food source provided by frugivorous fish are not in conflict in the tropical rivers studied. Therefore, these clearwater and blackwater rivers in the Brazilian Amazon show a balance between fisheries and conservation of frugivorous fish, which play an essential role in the functioning of tropical floodplain forest ecosystems.
102.
103.
Martins Tda M da Paixão TA Costa ÉA Pires Ade C Santos RL Borges ÁM 《Veterinary immunology and immunopathology》2011,139(2-4):277-281
Toll-like receptors (TLRs) and β-defensins are important components of the innate immune system. This study aimed to evaluate endometrial mRNA levels of TLRs (1/6, 2, 4, and 5) and β-defensin 5 in Holstein cows by quantitative real time RT-PCR. Uterine biopsies were performed from 6 to 12 h after parturition, and cows were divided into two groups: (i) cows with placental retention and clinical signs of uterine infection until 45 days postpartum (n=10) or (ii) cows with normal puerperium (n=10). All cows had detectable levels of TLRs and β-defensin 5 mRNAs, but these levels did not differ between groups (P>0.05). Levels of TLR4 mRNA had a positive and significant correlation with the time required for uterine involution in both groups. 相似文献
104.
Souza-Lemos C de-Campos SN Teva A Porrozzi R Grimaldi G 《Veterinary immunology and immunopathology》2011,142(3-4):147-155
We have recently introduced a macaque (Macaca mulatta) model of Leishmania braziliensis-induced self-healing cutaneous leishmaniasis in which the T cell-mediated inflammatory response effectively promotes parasite clearance and granuloma resolution. Here we show that macaques infected with a highly pathogenic L. braziliensis strain displayed longstanding granulomatous lesions which lasted until the end of the observation period (52 weeks). Immunoperoxidase staining of representative tissue sections indicated that distinct cell populations (CD3, CD4, CD8, CD20, Foxp3, CD20, CD68, HLA-DR, CCL2, and CXCL-10) change uniformly during infection, suggesting that the same components of the local immune response are working in unison. This model also confirmed that granuloma formation is orchestrated by diverse inflammatory mediators that are important for T helper type 1 (Th1) cell development and macrophage effector functions. Cytometry analysis of ex vivo granuloma-derived leukocytes revealed accumulation of distinct functional subsets of effector and regulatory T cells into the inflamed skin. We provide evidence that local interleukin (IL)-10 production by both Foxp3(+) and Foxp3(-) CD4(+) T subsets is likely important in promoting lesional granuloma maintenance. Further studying the immune suppression mechanisms that induces granulomas in L. braziliensis-infected macaques may reveal new opportunities for therapeutic control of this important human disease. 相似文献
105.
Franco-Acuña DO Pinheiro J Oliveira-Menezes A Brandolini SV DaMatta RA de Souza W 《Veterinary parasitology》2011,183(1-2):72-78
CD154 is a cell surface molecule expressed by activated T cells. CD40 and CD154 interaction is critically important in regulating humoral and cell-mediated immune responses. In this study we have investigated whether a DNA vaccine encoding rhoptry protein 1 (ROP1) of Toxoplasma gondii, and encoding ovine CD154 induces an enhanced ROP1-specific immune response in sheep. Two groups of twelve animals received two intramuscular injections, of a DNA plasmid encoding T. gondii ROP1 antigen (group 1) or an ROP1 antigen fused to ovine CD154 (group 2). There were two control groups of sheep. One was injected with an empty vector (group 3) and the other received no injections at all (group 4). The injection of the plasmid containing ROP1 (group 1) at weeks 0 and 4 induced a significant IgG2 response at week 2 which was amplified at week 4 after the booster injection and persisted to week 8 compared to the control animals in groups 3 and 4. For IgG1, significant differences from the control animals were only observed from week 5 onwards. The fusion of CD154 and ROP1 elicited significant IgG1 and IgG2 responses from week 1 which were amplified from weeks 5 to 8 compared to the control animals in groups 3 and 4. The IgG1 response was significantly higher in group 2 animals receiving pROP1-CD154 compared to group 1 receiving pROP1 only. There was no significant difference in IgG2 responses between groups 1 and 2. Significant differences in IFN-γ levels were only observed in treatment group 1 at week 2 and treatment group 2 at weeks 1 and 2 compared to the control animals. The results demonstrated that an intramuscular injection of pROP1-CD154 gene to sheep significantly enhanced their immune response and induced a mixed Th1/Th2 response while the intramuscular injection of pROP1 only induced a Th1-specific immune response. 相似文献
106.
Finotello R Ressel L Verin R Di Lollo S Baroni G Piccinini R Poli A 《Journal of zoo and wildlife medicine》2011,42(1):134-138
The histologic and immunohistochemical features of a case of mammary gland carcinoma are described in a 14-yr-old female tiger (Panthera tigris). Immunoreactivity to estrogen receptor (ER), progesterone receptor (PR), tumoral protein 53 (p53), vascular endothelial growth factor (VEGF), human epidermal growth factor receptor 2 (HER-2), and cyclooxigenase-2 (COX-2) was investigated. Neoplastic cells were negative for ER, PR, and p53 but showed positivity for VEGF, HER-2, and COX-2, both in the primary and the metastatic lesions. Histopathologic findings and immunohistochemistry results suggested that the malignant behavior of the reported case could be comparable with some aggressive cat mammary carcinomas. 相似文献
107.
Cruz Jaqueline Matos Montagnolli Renato Nallin Bidoia Ederio Dino 《Water, air, and soil pollution》2020,231(8):1-16
Water, Air, &; Soil Pollution - Phytoremediation is a cost-effective and relatively cleaner method for remediating contaminated areas using plants. Certain plants, including some sunflower... 相似文献
108.
Carlos A. Alvarez-González José L. Ortiz-Galindo Silvie Dumas Sergio F. Martínez-Díaz Dora E. Hernández-Ceballos Tanos Grayeb -Del Alamo Manuel Moreno-Legorreta Renato Penta-Martínez Roberto Civera-Cerecedo 《Journal of the World Aquaculture Society》2001,32(1):130-137
Abstract.— The effect on growth and survival of the initial stocking density (50, 100, 150, and 200 larvae/ L) in larval rearing of spotted sand bass was evaluated over 30 d in a closed recirculating system. Larvae were fed with rotifers, copepods, nauplii and adult Artemia , and spotted sand bass yolk-sac larvae. Water quality was monitored daily. The notochordal or standard length of sampled larvae was measured by image analysis. Specific growth rates at each density were compared by covariance analysis. Survival was estimated from day 15 to the end of the experiment, when a resistance test was used to evaluate the juvenile quality among densities. At the end of the experiment, mean standard length of larvae at lower densities was significantly larger ( P < 0.05) than at higher densities. Higher specific growth rates were found at lower densities. Significantly higher survival ( P < 0.05) was recorded for the lowest density, but the highest number of harvested fish was obtained with the highest densities (150 and 200 larvae/L). The lowest density also showed the significantly ( P < 0.05) higher survival after using a resistance test. We conclude the highest density can be used in larval rearing of spotted sand bass. However, better survival, growth, and seed quality are obtained at the lowest density. To recommend an optimal density for this specie, it is necessary to improve the water quality in the culture system and to make a cost-benefit study. 相似文献
109.
Borgarelli M Tarducci A Zanatta R Haggstrom J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(1):61-67
BACKGROUND: Systolic dysfunction associated with chronic mitral valve insufficiency (CMVI) has been demonstrated in experimental animal models and large breed (LB) dogs but has been reported as an uncommon finding in small breed (SB) dogs with naturally occurring disease. It has been suggested the myocardial failure could be, in part, because of an insufficient increase in left ventricular mass. HYPOTHESIS: To test if SB and LB dogs with CMVI and moderate heart failure have systolic dysfunction and if they have adequate eccentric hypertrophy. ANIMALS: Data from 38 SB and 18 LB dogs affected with CMVI were compared retrospectively with results from 2 groups of normal dogs (17 SB and 32 LB). METHODS: Systolic function was investigated echocardiographically by using percentage fractional shortening (FS), the ratio between observed and expected end-systolic diameter (ESD/ESDe), and end-systolic volume index (ESVI). Left ventricular hypertrophy was estimated by using the ratio between the thickness of the left ventricular free wall and the radius in diastole (h/R). RESULTS: Both affected SB and LB dogs had a significantly increased FS and ESVI (FS% SB 45.6 + 8.04 versus 40.06 + 8.9, P < .05; FS% LB 33.64 + 8.61 versus 27.3 + 7.3 P < .05; ESVI SB 30.0 +/- 2.3 mL/m2 versus 21.18 +/- 13.9 mL/m2, P < .05; ESVI LB 83.22 +/- 43.84 mL/m2 versus 36.43 +/- 13.30 mL/m2 versus P < .001). The h/R in affected animals was decreased (0.53 +/- 0.11 versus 0.41 +/- 0.12, P < .05 SB; 0.47 +/- 0.11 versus 0.38 +/- 0.09, P < .05, LB). CONCLUSIONS AND CLINICAL IMPORTANCE: Data from this study indicate that dogs with moderate heart failure caused by CMVI have systolic dysfunction. Inadequate hypertrophy of the left ventricle may be, in part, responsible for this finding. 相似文献
110.
Jaqueline Matos Cruz Ivo Shodji Tamada Paulo Renato Matos Lopes Renato Nallin Montagnolli Ederio Dino Bidoia 《Water, air, and soil pollution》2014,225(5):1-9
Biogas must be pretreated before its use; thus, both physical and chemical methods have been implemented to remove the fuel’s principal pollutants (CO2 and H2S). Additional removal methods that use microorganisms’ biological processes to eliminate pollutants have also emerged. A selection was made from six bacterial isolates to obtain consortia that removed CO2 and eventually H2S through the enrichment of cultures and the construction of clone libraries of gene 16S ribosomal DNA (rDNA). The results indicate that the principal differences between consortia were determined in the culture medium. C5 and C6 consortia had photosynthetic biomass 1.42 and 1.52 μg/ml, respectively, and concentration of dissolved CO2 100.6 and 99.1 mg/l, respectively. The clone libraries showed that Rhodopseudomonas sp. had percentages 46.6, 42.5, and 86.8 % in C4, C5, and C6, respectively; Xanthobacter sp., 24.5 %, Castellaniella sp., 18 % in C5, and Sphingobium sp., 39.2 % in C4. 相似文献