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排序方式: 共有840条查询结果,搜索用时 15 毫秒
831.
Natália Coelho Couto de Azevedo Fernandes Paloma Martins do Nascimento Angélica M. Sánchez-Sarmiento Rodrigo A. Ressio Cinthya dos Santos Cirqueira Cristina Takami Kanamura Júlia de Carvalho Silvana Mello Pereira da Silva Amanda Rezende Peruchi Julio César de Souza Junior Zelinda Maria Braga Hirano José Luiz Catão-Dias 《Journal of medical primatology》2020,49(2):65-70
832.
833.
Carlos Borges Filho Lucian Del Fabbro Silvana P. Boeira Ana Flávia Furian Lucielli Savegnago Letiére Cabreira Soares Antonio Luiz Braga Cristiano R. Jesse 《Cell biochemistry and function》2013,31(2):152-158
From a pharmacological point of view, organoseleniums are compounds with important and interesting antioxidant and biological activities. The aim of this study was to evaluate the hepatoprotective effect of bis(4‐methylbenzoyl) diselenide (BMD) against carbon tetrachloride (CCl4)–induced oxidative damage in mice. The animals received BMD (25 mg/kg p.o., for 3 days), and after 1 day, CCl4 (1 mg/kg body weight) was administered by intraperitoneal route. One day after the CCl4 exposure, the animals were euthanized for biochemical and histological analysis. Treatment with BMD (25 mg/kg p.o.) protected against aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma‐glutamyl transferase and lactate dehydrogenase activity increases induced by CCl4 plasma exposure. Treatment with BMD (25 mg/kg) protected against increases in thiobarbituric reactive species and decreasing non‐protein thiols and ascorbic acid levels in liver of mice. Catalase and superoxide dismutase activity inhibition in the liver caused by CCl4 were protected by treatment with BMD (25 mg/kg). Glutathione S‐transferase activity was inhibited by CCl4 and remained unaltered even after treatment with BMD. Sections of liver from CCl4‐exposed mice presented an intense infiltration of inflammatory cells and loss of the cellular architecture. BMD (25 mg/kg) attenuated CCl4‐induced hepatic histological alterations. The results demonstrated the hepatoprotective effects of BMD in the mouse liver, possibly by modulating the antioxidant status. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
834.
Daniela Camargos Costa Vanessa Pecini da Cunha Gabriela Maria Pereira de Assis Júlio César de Souza Junior Zelinda Maria Braga Hirano Mércia Eliane de Arruda Flora Satiko Kano Luzia Helena Carvalho Cristiana Ferreira Alves de Brito 《Memórias do Instituto Oswaldo Cruz》2014,109(5):641-643
Blood infection by the simian parasite, Plasmodium simium, was
identified in captive (n = 45, 4.4%) and in wild Alouatta clamitans
monkeys (n = 20, 35%) from the Atlantic Forest of southern Brazil. A single malaria
infection was symptomatic and the monkey presented clinical and haematological
alterations. A high frequency of Plasmodium vivax-specific
antibodies was detected among these monkeys, with 87% of the monkeys testing positive
against P. vivax antigens. These findings highlight the possibility
of malaria as a zoonosis in the remaining Atlantic Forest and its impact on the
epidemiology of the disease. 相似文献
835.
Using the method of in situ hybridization of ribosomal DNA with DNA of isolated nuclei, a study was made of localization and relative content of ribosomal genes in the Purkinje cells and other cells of the rat cerebellum. It has been shown that various cells of cerebellum have, on the average, the same number of ribosomal genes. A subpopulation with amplified ribosomal genes have been found among the nuclei of Purkinje's cells. 相似文献
836.
Poliana de Oliveira Figueiredo André Tavares da Silva-Fernandes Bruno Eduardo Fernandes Mota Galileu Barbosa Costa Iara Apolinário Borges Paulo César Peregrino Ferreira J?natas Santos Abrah?o Erika Martins Braga Erna Geessien Kroon Giliane de Souza Trindade 《Memórias do Instituto Oswaldo Cruz》2015,110(6):804-808
Vaccinia virus naturally circulates in Brazil and is the causative agent of a
zoonotic disease known as bovine vaccinia (BV). We retrospectively evaluated two
populations from the Amazon and Southeast Regions. BV outbreaks had not been reported
in these regions before sample collection. Neutralising antibodies were found in 13
individuals (n = 132) with titres ranging from 100 ≥ 6,400 neutralising units/mL.
Univariate analysis identified age and vaccination as statistically significant risk
factors in individuals from the Southeast Region. The absence of detectable
antibodies in vaccinated individuals raises questions about the protection of
smallpox vaccine years after vaccination and reinforces the need for surveillance of
Orthopoxvirus in Brazilian populations without evidence of previous outbreaks. 相似文献
837.
Jorge Alfaro-Montoya André Braga Maribelle Vargas Rodolfo Umaña-Castro 《Invertebrate reproduction & development.》2017,61(1):9-17
The present study demonstrates ultrastructurally the model of Litopenaeus vannamei male sexual maturation and spermatozoal capacitation. The results show that phase 1 of the model occurred in the seminiferous tubules and includes spermatogenesis. In this phase, throughout differentiation of spermatogonia into late spermatids the following processes were observed: (1) decondensation of chromatin; (2) rupture of the nuclear envelope; (3) reduction of the cytoplasm and degeneration of organelles; (4) formation of the acrosome via fusion of cytoplasmic vesicles. Phase 2 comprised of spermatozoal maturation, a process that started with the transfer of late spermatids into the seminiferous ducts and ended with the formation of the acrosomal spike in the terminal ampoules. During this phase, development of the subacrosomal region and lateral electron-dense particles occurred in the seminiferous ducts, which is a novel finding of this species. Phase 3 was observed after spermatophore placement on the female thelycum and was mainly characterized by ultrastructural changes in the nucleus and the subacrosomal region. These results are in agreement with the model of male sexual maturation and spermatozoal capacitation proposed for L. vannamei. 相似文献
838.
Some moths species are considered good indicators of habitat quality because they are very responsive to human disturbance, vegetation type, and successional processes. However, Saturniidae moths have not yet been considered as indicators of environmental quality. Little is known on the distribution of moth species in different vegetation types and the moths’ seasonal variations in the Brazilian savannah. Therefore, this study aims to describe the spatial distribution and temporal patterns of moths belonging to the Saturniidae family in two vegetation types—Cerrado sensu stricto on rocky outcrops and semi-deciduous forest—in both the rainy and dry seasons. It addresses the influence of the climatic seasons and vegetation types on abundance, richness, and species composition to describe the temporal and spatial distribution patterns and the relationship between the ecological aspects and the life history of these moths. This study was conducted in the Cerrado phytogeographical domain, in Pireneus State Park, Goiás, Brazil. The results revealed that most Saturniidae species sampled are present during the rainy season and typically found in forest habitats. Furthermore, a clear positive connection was found between the abundance pattern and rainfall seasonality and humid habitats; this is apparently related to the physiological tolerance of these moths, due to rudimentary mouthparts during their adulthood. Thus, rainfall and a forest habitat are important to and fundamental requirements for the persistence of the Saturniidae species in the Cerrado domain. Based on the results of this study, we suggest the use of saturniid species as indicators of changes in vegetation and climatic conditions. 相似文献
839.
AIM: To evaluate height, bone growth, areal bone mineral density (aBMD), volumetric bone mineral density (vBMD) and markers of bone turnover in a group of patients affected by congenital adrenal hyperplasia (CAH). PATIENTS: There were 50 patients (23 males, 27 females), aged 1-28 years, affected by CAH due to 21-hydroxylase deficiency: 27 with the salt-wasting (SW); 14 with the simple virilizing (SV), and 9 with the nonclassical (NC) forms. METHODS: Bone morphometry was evaluated with the metacarpal index (MI) and lumbar aBMD and vBMD (L2-L4) by dual energy X-ray absorptiometry. Serum osteocalcin was used as a marker of bone formation, while urinary cross-linked N-telopeptides of type-I collagen and free deoxypyridinoline levels were evaluated as indexes of bone resorption. RESULTS: The height standard deviation score (SDS) was -0.41 +/- 1.4 in SW patients, -0.01 +/- 1.9 in SV patients, and -0.01 +/- 2.3 in NC patients. There was no significant difference among groups and against zero. The MI SDS was also not different between groups and against zero. aBMD was significantly lower in the pubertal patients compared with normal values, but only when patients with the SW and SV forms were considered together (p < 0.05). vBMD was significantly reduced in all patients with the classical form. Bone markers were not different in patients and controls. CONCLUSION: Our study shows that normal height can be attained in CAH patients; however, an impairment in bone growth and mineralization may be found in adolescents and young adults affected by the classical form. 相似文献
840.
O A Kuprianova V A Mordvinov I P Ivanova O L Krugleeva E A Braga V V Nosikov V A Kozlov V P Lozovo? 《Biulleten' eksperimental'no? biologii i meditsiny》1991,112(12):619-621
We investigated cytoplasmic RNA from the peripheral blood cells of pollinosis patients. Increased levels of IL-I mRNA were registered in neutrophils of patients suffering from pollinosis for a long time. Neutrophils from patients at the time of exacerbation of pollinosis responded to stimuli less than the cells from healthy donors. During remission the activated neutrophils from pollinosis patients and those from healthy donors had same levels of IL-I mRNA. 相似文献