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11.
Radan Elvis Matias de Oliveira Giovanna Almeida Santoro Augusto Carlos da Bôaviagem Freire Fernanda Löffler Niemeyer Attademo Stella Almeida Lima Aline da Costa Bomfim Ana Bernadete Lima Fragoso Flávio José de Lima Silva Simone Almeida Gavilan Moacir Franco de Oliveira 《Anatomia, histologia, embryologia》2020,49(1):25-30
The aortic arrangement is an important structure associated with the maintenance of homeostasis. Based on this information, this study was conducted to describe the collateral arteries of the aortic arch of Antillean manatee and define the standard model for the species. Three specimens, an adult male, adult female and a male neonate, all strandings on the coast of the state of Rio Grande do Norte, Brazil, were used. The study was performed in the Laboratory of Morphophysiology of Vertebrates of the Federal University of Rio Grande do Norte, where in situ photographs were taken to demonstrate their topography. Subsequently, their hearts were removed and fixed in 10% formaldehyde and after 72 hr were dissected and analysed, obtaining schematic drawings and photographs of the vascular arrangement. The aortic arch was represented by three collateral arteries identified as the brachiocephalic trunk, left common carotid artery and left subclavian artery. This arrangement was similar to that found for other sirenians, and yet, for other mammals like hooded seal, murine, margarita island capuchin, black-handed tamarin, Mongolian gerbil and human. The morphological similarity presented in this study with different species of mammals, including humans, may contribute valuable information from an evolutionary point of view. 相似文献
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CL SCHWARTZKOFF JR EGERTON† DJ STEWART‡ PR LEHRBACH§ TC ELLEMAN¶ PA HOYNE¶ 《Australian veterinary journal》1993,70(4):123-126
SUMMARY A multivalent footrot vaccine has been developed, containing pilus antigens produced in recombinant Pseudomonas aeruginosa and representing all nine serogroups of Dichelobacter (Bacteroides) nodosus commonly recognised in the field. The responses of sheep to the multivalent vaccine have been compared with those to monovalent vaccines representing only a single serogroup. Antigenie competition between serogroups occurred in sheep immunised with the multivalent formulation, but high levels of protection were still achieved. The study showed that in multivalent footrot vaccines, antigenic competition is predominantly due to the presence of a family of immunologically-related pilus antigens rather than to interference by extraneous proteins. 相似文献
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The purpose of the present study was the genetic characterization, sequencing and phylogenetic analysis of 18S rDNA sequences of Cryptosporidium isolates obtained from different animal hosts in Brazil. Fecal samples containing Cryptosporidium oocysts were obtained from chickens, ducks, quails, guinea pigs, dairy calves, dogs and cats. For amplification of 18S rDNA sequences the Secondary-PCR product of the extracted DNA from fecal suspension of each studied animal was utilized. The primary genetic characterization of Cryptosporidium sp. was performed using RFLP with the enzymes SspI and VspI. DNA samples were sequenced and subjected to phylogenetic analysis. The results showed C. baileyi infecting two ducks and one quail and C. melagridis infecting one chicken. The sequences obtained from Cryptosporidium sp. infecting guinea pigs were not identified within groups of known Cryptosporidium species. The isolates found parasitizing cats and one dog were diagnosed as C. felis and C. canis, respectively. One isolate of calf origin was identified as C. parvum. The phylogenetic analysis showed clear distribution of isolates between two Cryptosporidium sp. groups according to their gastric or intestinal parasitism. A great genetic distance was observed between C. felis and C. canis from Brazil when compared to the reference sequences obtained from GenBank. The results obtained during this study constitute the first report of rDNA sequences from C. baileyi, C. meleagridis, C. felis, C. canis and C. parvum isolated in Brazil. 相似文献
14.
Effects of supplementation of medium with different antioxidants during in vitro maturation of bovine oocytes on subsequent embryo production 
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下载免费PDF全文 TC Sovernigo PR Adona PS Monzani S Guemra FDA Barros FG Lopes CLV Leal 《Reproduction in domestic animals》2017,52(4):561-569
The aim of this study was to assess the effects of different antioxidants on the levels of reactive oxygen species (ROS) and glutathione (GSH) in oocytes during in vitro maturation (IVM), as well as on the production of embryos. Oocyte of slaughterhouse‐derived cattle ovaries were placed in IVM with different antioxidants: quercetin (2 μM), cysteamine (100 μM), carnitine (0.5 mg/ml), vitamin C (50 μg/ml) or resveratrol (2 μM). Oocytes matured without any antioxidant supplementation were used as control. The oocytes were assessed for maturation rates and for ROS and GSH levels by fluorescence staining in 2′,7′‐dichlorodihydrofluorescein diacetate and Cell Tracker Blue, respectively. Embryo production was assessed in terms of cleavage, blastocysts and hatching rates and embryo cell numbers. The results expressed in arbitrary fluorescence units showed ROS reduction (p < .05) in the groups with quercetin (27.5 ± 3.4), vitamin C (27.1 ± 3.0) or resveratrol (28.1 ± 4.7), in comparison with those with cysteamine (34.9 ± 4.5), carnitine (34.6 ± 3.8) or to the control group (36.5 ± 5.2). GSH levels increased (p < .05) in cysteamine (63.5 ± 5.5) or carnitine (60.8 ± 4.4) groups in comparison with quercetin (52.7 ± 5.1), vitamin C (53.0 ± 3.8), resveratrol (53.1 ± 4.4) or to the control (49.6 ± 4.5). Nuclear maturation cleavage and hatched blastocysts rates did not differ (p > .05) between groups. However, blastocyst rates after in vitro fertilization in quercetin (53.5 ± 3.9%), vitamin C (52.1 ± 3.1%) resveratrol (54.2 ± 4.0%), cysteamine (52.4 ± 2.7%) or carnitine (54.2 ± 3.1%) groups were higher (p < .05) than in the control (47.2 ± 2.7%). Total cell numbers in embryos from the vitamin C, resveratrol, cysteamine or carnitine groups were higher than in quercetin and control groups, which were similar to each other. The results suggest that using antioxidants during IVM may reduce oxidative stress either by decreasing ROS levels directly or by increasing GSH levels in oocytes, depending on the type of antioxidant used. Overall, oxidative stress control during IVM with the antioxidants examined here improved blastocyst development with similar efficacy. 相似文献
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Nagib M. A. Nassar Dalva G. Ribeiro Nayra N. Bomfim Pollyanna T. C. Gomes 《Genetic Resources and Crop Evolution》2011,58(6):831-835
A new species of Manihot has been collected from Fortaleza, Ceará state, Brazil. It was grown at the living collection in the experimental station,
University of Brasilia since 1980 and left for natural reproduction. It bred true during all these years giving rise to identical
typical plants of the ancestor one. The closest species to it is M. glaziovii. Apparently this new species was formed by sporadic hybridization between M. glaziovii and cassava itself in its natural habitat, Ceará. It possesses morphological marker gene of the latter one which is ribbed
fruit that is found only in cassava. Interspecific hybrids produced experimentally between M. glaziovii and cassava showed similar morphological markers. Exam of its ovules revealed formation of multiple embryos, an indicator
of apomixis. Grafting it with common cassava was compatible, giving increased root size up to seven times. 相似文献
17.
Shape-Controlled Synthesis of Colloidal Platinum Nanoparticles 总被引：1，自引：0，他引：1
TS Ahmadi ZL Wang TC Green A Henglein MA El-Sayed 《Science (New York, N.Y.)》1996,272(5270):1924-1926
The shapes and sizes of platinum nanoparticles were controlled by changes in the ratio of the concentration of the capping polymer material to the concentration of the platinum cations used in the reductive synthesis of colloidal particles in solution at room temperature. Tetrahedral, cubic, irregular-prismatic, icosahedral, and cubo-octahedral particle shapes were observed, whose distribution was dependent on the concentration ratio of the capping polymer material to the platinum cation. Controlling the shape of platinum nanoparticles is potentially important in the field of catalysis. 相似文献
18.
In order to compare natural infection by Cyptosporidium sp. and Giardia sp. in clinically healthy dogs living in two situations (animal shelter and household pets), we conducted 166 faecal exams using the technique of centrifugation-flotation in a sugar-saturated solution. Of the faecal samples, 94 came from shelter dogs and 72 from house pets. Eighty-two (49.4%) contained parasite eggs, cysts or oocysts. Of these, four (2.41%) contained Cryptosporidium sp. oocysts and 52 (31.33%) contained Giardia sp. cysts. There was no statistically significant difference between the origin of the dogs and Cryptosporidium sp. infection. Infection by Cryptosporidium sp. was not associated with the living conditions and sex. With respect to Giardia sp., we observed a statistically significant difference (p < 0.001) between the shelter dogs (45%) and the household pets 12.3%. There was no association of infection by Giardia sp. with age or sex. 相似文献
19.
Dispersions of colloidal particles in cholesteric liquid crystals form an unusual solid by stabilizing a network of linear defects under tension in the ideal layered structure of the cholesteric. The large length scales of the cholesteric liquid crystals allowed direct observation of the network structure, and its properties were correlated with rheological measurements of elasticity. This system serves as a model for a class of solids formed when particles are mixed with layered materials such as thermotropic and lyotropic smectic liquid crystals and block copolymers. 相似文献
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Direct electrical transport measurements in a diamond anvil cell provide evidence for the metallization of cesium iodide (CsI) at a pressure of 115 gigapascals. A drop in the temperature dependence of the resistance was found at pressures above 180 gigapascals, indicating that the CsI was superconductive. The superconductivity changed under the influence of a magnetic field to a lower critical temperature and disappeared above 0.3 tesla. The highest critical temperature at which superconductivity was observed was 2 kelvin, and the critical temperature decreased with increasing pressure. 相似文献