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排序方式: 共有231条查询结果,搜索用时 15 毫秒
221.
The histopathology in Paulicea lutkeni naturally infected with Megathylacus brooksi and Jauela glandicephalus is described. Megathylacus brooksi attaches to the epithelium of the anterior intestine by means of suckers, resulting in damage to the epithelium, haemorrhages and lymphocyte infiltration. Jauela glandicephalus penetrates through all layers of the intestine. This penetration elicits an intense host-response resulting in the hyperplasy of connective tissue and formation of a nodule surrounding the scolex of the parasite. Lymphocyte infiltration was observed. Concurrent infections were found in some specimens. 相似文献
222.
de Abreu Filipe Vieira Santos Macedo Mariana Viana da Silva Alex Junio Jardim de Oliveira Cirilo Henrique de Ottone Vinícius Oliveira de Almeida Marco Antônio Barreto dos Santos Edmilson da Cardoso Jader Cruz Campos Aline Scarpellini da Silva Claudia Maria Dornelles da Silva Amanda Gonzales de Andrade Miguel Souza Bernis Valéria Magro Octaviano Bernis Filho Walter Octaviano de Trindade Giliane Souza Albuquerque George Rego da Sevá Anaiá Paixão Ribeiro Bergmann Morais Teixeira Danilo Simonini Campos Fabrício Souza Franco Ana Cláudia Roehe Paulo Michel de Oliveira Danilo Bretas 《EcoHealth》2021,18(4):414-420
EcoHealth - In 2019, a new coronavirus disease (COVID-19) was detected in China. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was capable to infect domestic and captive mammals like... 相似文献
223.
Muthulekha Swamydas Krista Ricci Stephen L. Rego Didier Dréau 《Cell Adhesion & Migration》2013,7(3):315-324
Stromal chemokine gradients within the breast tissue microenvironment play a critical role in breast cancer cell invasion, a prerequisite to metastasis. To elucidate which chemokines and mechanisms are involved in mammary cell migration we determined whether mesenchymal D1 stem cells secreted specific chemokines that differentially promoted the invasion of mammary tumor cells in vitro. Results indicate that mesenchymal D1 cells produced concentrations of CCL5 and CCL9 4- to 5-fold higher than the concentrations secreted by 4T1 tumor cells (P < 0.01). Moreover, 4T1 tumor cell invasion toward D1 mesenchymal stem cell conditioned media (D1CM), CCL5 alone, CCL9 alone or a combination CCL5 and CCL9 was observed. The invasion of 4T1 cells toward D1 mesenchymal stem CM was dose-dependently suppressed by pre-incubation with the CCR1/CCR5 antagonist met-CCL5 (P < 0.01). Furthermore, the invasion of 4T1 cells toward these chemokines was prevented by incubation with the broad-spectrum MMP inhibitor GM6001. Additionally, the addition of specific MMP9/MMP13 and MMP14 inhibitors prevented the MMP activities of supernatants collected from 4T1 cells incubated with D1CM, CCL5 or CCL9. Taken together these data highlight the role of CCL5 and CCL9 produced by mesenchymal stem cells in mammary tumor cell invasion. 相似文献
224.
Camila Ximenes Eduardo Brand?o Paula Oliveira Abraham Rocha Tamisa Rego Rafael Medeiros Ana Aguiar-Santos Jo?o Ferraz Christian Reis Paulo Araujo Luiz Carvalho Fabio L Melo 《Memórias do Instituto Oswaldo Cruz》2014,109(8):978-983
The Global Program for the Elimination of Lymphatic Filariasis (GPELF) aims to
eliminate this disease by the year 2020. However, the development of more specific
and sensitive tests is important for the success of the GPELF. The present study
aimed to standardise polymerase chain reaction (PCR)-based systems for the diagnosis
of filariasis in serum and urine. Twenty paired biological urine and serum samples
from individuals already known to be positive for Wuchereria bancrofti
were collected during the day. Conventional PCR and semi-nested PCR assays
were optimised. The detection limit of the technique for purified W.
bancrofti DNA extracted from adult worms was 10 fg for the internal
systems (WbF/Wb2) and 0.1 fg by using semi-nested PCR. The specificity of the primers
was confirmed experimentally by amplification of 1 ng of purified genomic DNA from
other species of parasites. Evaluation of the paired urine and serum samples by the
semi-nested PCR technique indicated only two of the 20 tested individuals were
positive, whereas the simple internal PCR system (WbF/Wb2), which has highly
promising performance, revealed that all the patients were positive using both
samples. This study successfully demonstrated the possibility of using the PCR
technique on urine for the diagnosis of W. bancrofti infection. 相似文献
225.
226.
Palaeocarpological (archaeobotanical) analysis of Neolithic and Bronze Age levels of the Buraco da Pala site (Bragança, Portugal) provides evidence of considerable agricultural activity. Triticum, Hordeum and Vicia predominated, though Pisum, Lens, Vitis, Linum and Papaver were also found. Most wheat grains were spheroidal and were identified as Triticum aestivum subsp. sphaerococcum, in disagreement with recent suggestions that taxa with spheroidal grains have never been present in the Iberian Peninsula. Quercus and Pinus seed indicated that gathering activities supplemented agricultural production. 相似文献
227.
228.
Fabrine Silva Alves José de Arimatéia Rodrigues Do Rego Marcondes Lima Da Costa Luiz Fernando Lobato Da Silva Renato Araújo Da Costa 《Journal of biomolecular structure & dynamics》2020,38(9):2792-2799
Communicated by Ramaswamy H. Sarma 相似文献
229.
230.
Letícia do Nascimento Andrade de Almeida Rego Kaio Cesar Chaboli Alevi Maria Tercília Vilela de Azeredo-Oliveira 《Fly》2016,10(1):47-52
The genus Zaprionus consists of approximately 60 species of drosophilids that are native to the Afrotropical region. The phylogenetic position of Zaprionus within the Drosophilidae family is still unresolved. In the present study, ultrastructural features of spermatozoa of 6 species of Zaprionus as well as the species Drosophila willistoni and Scaptodrosophila latifasciaeformis were analyzed. The ultrastructure revealed that the species have the same flagellar ultrastructure. Two mitochondrial derivatives, one larger than the other, close to the axoneme were present, primarily in D. willistoni (subgenus Sophophora). Except for Z. davidi and Z. tuberculatus, the analyzed species had paracrystalline material in both mitochondrial derivatives. Moreover, the testes showed 64 spermatozoa per bundle in all of the species. In the cluster analysis, 6 Zaprionus species were grouped closely, but there were some incongruent positions in the cladogram. The results indicated that sperm ultrastructure is an important tool for elucidating the phylogeny and taxonomy of insects. 相似文献