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排序方式: 共有818条查询结果,搜索用时 15 毫秒
811.
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
812.
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
813.
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
814.
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
815.
Joo V. Comasseto Leonardo F. Assis Leandro H. Andrade Iracema H. Schoenlein-Crusius Andr L.M. Porto 《Journal of Molecular Catalysis .B, Enzymatic》2006,39(1-4):24-30
Seven strains of the fungus Aspergillus terreus isolated from several provenances in Brazil, catalyzed biotransformations of ortho-, meta- and para-nitrophenyl compounds at different pH values. ortho-Nitroacetophenone and meta-nitroacetophenone were transformed into (S)-(+)-1-(ortho-nitrophenyl)ethanol and (S)-(−)-1-(meta-nitrophenyl)ethanol with high enantiomeric excess (e.e. ≥98%) and conversion (≥98%) by all the strains used. Deracemization of (RS)-1-(meta-nitrophenyl)ethanol was obtained with high selectivity (e.e. up to ≥98%) and good conversion (c 98%). The biotransformations in acidic medium using these fungus strains were more efficient than under basic or neutral conditions. 相似文献
816.
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
817.
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
818.
Mammillary body (Mb) cell structures were compared following four different procedures for fixation, in order to find one procedure which would be suitable both for silver impregnation methods and electron microscopy. Fixatives compared were: (1) formaldehyde (4% pH 5.5), Mb from a frozen-section; (2) formaldehyde (4% pH 7.2.), Mb from a frozen-section; (3) glutaraldehyde-formaldehyde (1%-4% pH 6.0), Mb from a frozen-section; and (4) glutaraldehyde-formaldehyde (3%-2% pH 7.2), unfrozen Mb. All solutions were perfused into the left ventricle of the heart of anesthetized rats, except for the animal from which the unfrozen tissue was obtained. The Mb was excised from the fresh brain and immediately placed in a fixative solution. After aldehyde fixation, the tissues were further fixed in 1% OsO4 (pH 7.4), dehydrated, embedded in Epon-Araldite and double-stained with uranyl acetate and lead citrate. Comparisons of mitochondria, myelin, synapses, neurofilaments and synaptic membranes indicated that the perfusion of 4% formaldehyde is suitable for both electron microscopy and silver impregnation, and was preferable to the other fixatives tested. 相似文献