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941.
Pinto AE André S Mendonça E Silva G Soares J 《The International journal of biological markers》2003,18(1):7-12
Fine-needle aspiration cytology (FNAC) is essential for making a diagnosis in advanced breast cancer. The determination of hormone receptors in the material obtained is useful for predicting patient response to endocrine therapy, but the prognostic value of hormone receptor expression as well as the clinical utility of DNA flow cytometry are controversial. The aim of this prospective study with long-term follow-up (median: 81 months) was to evaluate these biomarkers in relation to overall survival in a series of 392 patients with advanced breast cancer (stage IIB, n=106; IIIA, n=66; IIIB, n=174; and IV, n=46) using FNAC. Estrogen and progesterone receptor expression was found in 65.1% and 46.1% of the tumors, respectively. Hormone receptors were not found to be associated with clinical staging. DNA aneuploidy was present in 70.9% of the cases and the median S-phase fraction (SPF) was 9.4%. There was a significant correlation of aneuploidy and high SPF with lack of hormone receptors. In univariate analysis, advanced disease stage, absence of hormone receptors, DNA aneuploidy and high SPF showed a statistically significant correlation with poor clinical outcome. In multivariate analysis, disease stage, progesterone receptors and DNA ploidy retained independent prognostic significance in relation to overall survival. These data indicate that progesterone receptor expression and DNA ploidy are independent prognostic factors in advanced breast cancer. 相似文献
942.
Semedo T Santos MA Lopes MF Figueiredo Marques JJ Barreto Crespo MT Tenreiro R 《Systematic and applied microbiology》2003,26(1):13-22
The occurrence of several virulence traits (cytolysin, adhesins and hydrolytic enzymes) was investigated in a collection of 164 enterococci, including food and clinical isolates (from human and veterinary origin), as well as type and reference strains from 20 enterococcal species. Up to fifteen different cyl genotypes were found, as well as silent cyl genes. The occurrence of the cyl operon and haemolytic potential seems to be widespread in the genus. A significant association of this virulent trait with clinical isolates was found (p < 0.05). High levels of incidence were also observed for genes encoding surface adhesins (esp, efaA(fs), efaA(fm)), agg and gelE, irrespectively of species allocation and origin of strains. Although gelE behaves as silent in the majority of the strains, gelatinase activity predominates in clinical isolates, whereas lipase and DNase were mainly detected in food isolates pointing to their minor role as virulence determinants. No hyaluronidase activity was detected for all strains. Numerical hierarchic data analysis grouped the strains in three main clusters, two of them including a total of 50 strains with low number of virulence determinants (from 2 to 7) and the other with 114 strains with a high virulence potential (up to 12 determinants). No statistical association was found between virulence clusters and species allocation (p > 0.10), strongly suggesting that virulence determinants are a common trait in the genus Enterococcus. Clinical strains seem to be significantly associated with high virulence potential, whereas food, commensal and environmental strains harbour fewer virulence determinants (p < 0.01). A high level of relative diversity in virulence patterns was observed (Shannon's index varies from 0.95 to 1.0 among clusters), reinforcing the strain-specific nature of the association of virulence factors. Although a low risk seems to be associated with the use of enterococci in long-established artisanal cheeses, screening of virulence traits and their cross-synergies must be performed, particularly for commercial starters, probiotic strains and products to be used by high risk population groups. 相似文献
943.
Chrysanthemum: advances in tissue culture, cryopreservation, postharvest technology, genetics and transgenic biotechnology 总被引:8,自引:0,他引:8
Teixeira da Silva JA 《Biotechnology advances》2003,21(8):715-766
Members of the Chrysanthemum-complex include important floricultural (cut-flower) and ornamental (pot and garden) crops, as well as plants of culinary, medicinal and (ethno)pharmacological interest. The last 35 years have seen a tremendous emphasis on their in vitro tissue culture and micropropagation, while the latter 10–15 years has seen a surge in transformation experiments, all aimed at ameliorating aesthetic and growth characteristics of the plants. This review highlights all available literature that exists on ornamental Chrysanthemum in vitro cell, tissue and organ culture, micropropagation and transformation. 相似文献
944.
Root distribution of a Mediterranean shrubland in Portugal 总被引:4,自引:0,他引:4
The distribution of roots of an Erica (Erica scoparia and Erica lusitanica) dominated Mediterranean maquis was studied using three different approaches: root counts on trench walls (down to 120 cm), estimation of the maximum rooting depth using an allometric relationship and estimation of fine root biomass and fine root length using soil cores (down to 100 cm). Roots were classified according to diameter (fine, 1.0 mm; small, 1.1–5.0 mm; medium, 5.1–10.0 mm; coarse, >10.0 mm) and species (Erica sp., Pteridium aquilinum, Rubus ulmifolius and Ulex jussiaei). The depth corresponding to 50% of all roots (D
50) was determined by fitting a new model to the cumulative root distribution. Fine roots represented 96% of root counts. Root counts of Erica represented 59%, Ulex 34%, Rubus 6% and Pteridium 1%. Overall root counts showed a D
50 of 26 cm. D
50 was higher for Ulex (40 cm) and Erica (22 cm), than for Pteridium (9 cm) and Rubus (3 cm). D
50 for fine roots was 27 cm, for small roots 11 cm, for medium roots 6 cm and for coarse roots 4 cm. The estimated average maximum rooting depth of the 28 deepest Erica roots was 222 cm. The deepest Erica root was estimated to reach 329 cm. A total of 82% of roots growing deeper than 125 cm were not reaching more than 175 cm. The overall fine root length density ranged from 4.6 cm/cm3 at 10 cm to 0.8 cm/cm3 at 80 cm. The overall fine root biomass ranged from 7.7 mg/cm3 at 10 cm to 0.6 mg/cm3 at 40 cm. D
50 for root biomass was 12 cm and D
50 for root length was 14 cm. Fine root biomass was estimated as 1.6 kg/m2 and the respective root length as 18.7 km/m2. 相似文献
945.
946.
947.
Yoshinari NH Abrão MG Bonoldi VL Soares CO Madruga CR Scofield A Massard CL da Fonseca AH 《Memórias do Instituto Oswaldo Cruz》2003,98(3):311-318
This paper reports a case of coinfection caused by pathogens of Lyme disease and babesiosis in brothers. This was the first case of borreliosis in Brazil, acquired in Cotia County, State of S o Paulo, Brazil. Both children had tick bite history, presented erythema migrans, fever, arthralgia, mialgia, and developed positive serology (ELISA and Western-blotting) directed to Borrelia burgdorferi G 39/40 and Babesia bovis antigens, mainly of IgM class antibodies, suggestive of acute disease. Also, high frequencies of antibodies to B. bovis was observed in a group of 59 Brazilian patients with Lyme borreliosis (25.4%), when compared with that obtained in a normal control group (10.2%) (chi-square = 5.6; p < 0.05). Interestingly, both children presented the highest titers for IgM antibodies directed to both infective diseases, among all patients with Lyme borreliosis. 相似文献
948.
dos Santos CM Jurberg J Galvão C Rocha Dda S Fernandez JI 《Memórias do Instituto Oswaldo Cruz》2003,98(7):939-944
The subfamily Triatominae is actually represented by 137 species distributed among 6 tribes and 19 genera. Within this subfamily, the genus Panstrongylus, Berg 1879, is composed by 13 species widespread in sylvatic, peridomestic, and domestic habitats of Neotropical regions. These species are vectors of Chagas disease and consequently are found associated with its main hosts, such as birds and mammals. Interest in species of this genus has been increasing in the last few years. Reports of several authors indicate these Triatominae to invade and colonize houses, increasing their epidemiological significance. Morphometry was used in this study to investigate correlations among possible closely related species. We measured 224 specimens among 13 species through a set of metric variables of the head. The results indicated that the genus Panstrongylus seems to be homogeneous since 10 of the 14 species were shown to be closely related. 相似文献
949.
de Araújo-Coutinho CJ Cunha Ade B Serra-Freire NM de Mello RP 《Memórias do Instituto Oswaldo Cruz》2003,98(5):697-702
The study was set up to evaluate the impact of two commercial larvicide formulations, Bacillus thuringiensis serovar israelensis base (Bti) at 15 ppm/1 min and temephos at 0.03 ppm of active ingredient, used to control Simulium pertinax populations, on associated non-target entomofauna occupying the same breeding sites. The experiments were carried out on the Pedra Branca and Muricana rivers, on the slopes of Serra do Mar massif, municipality of Paraty, state of Rio de Janeiro, Brazil. Bti was applied to the river Pedra Branca and temephosto theriver Muricana. On both rivers, treatment and control sections were labeled as such, each one with two observation posts: slow moving water and fast water regions respectively. Artificial substrata was used to evaluate the abundance of associated entomofauna. Attached immature stages of arthropods were removed from both of its surfaces fortnightly. Were collected, from the two rivers, 28 477 specimens of the entomofauna associated with S. pertinax. The families Hydropsychidae, Chironomidae, Bactidae, Simuliidae, Blephariceridae and Megapodagrionidae were represented. These was an impact of temephos on the entomofauna associated with S. pertinax only in Simuliidae and Chironomidae, and to Bti only in Simuliidae. However, the reduction in their numbers was not statistically significant. 相似文献
950.
Felippe-Bauer ML Cáceres AG Silva CS Valderrama-Bazan W Gonzales-Perez A 《Memórias do Instituto Oswaldo Cruz》2003,98(8):1051-1058
Two new species of the Culicoides paraensis species group, C. diversus Felippe-Bauer and C. peruvianus Felippe-Bauer, are described and illustrated based on female specimens from Amazonian region of Peru. A systematic key, table with numerical characters of females, and distribution of species of the C. paraensis group are given. 相似文献