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1.
Chinese Journal of Radiological Health ; (6): 507-511, 2022.
Article Dans Chinois | WPRIM | ID: wpr-965828

Résumé

Objective To investigate the correlation between the features of multimodal magnetic resonance imaging (MRI) and the expression of human epidermal growth factor receptor-2 (HER-2) in ductal carcinoma in situ (DCIS). Methods A total of 53 patients with DCIS confirmed by surgery and pathology in Dezhou Second People’s Hospital from September 2018 to June 2021 were analyzed retrospectively. The patients were divided into HER-2 positive group (29 cases) and HER-2 negative group (24 cases). MRI features were compared between the two groups. Results There were significant differences in the internal enhancement characteristics, microvascular sign, and time-intensity curve type between the two groups (P < 0.05). There were no significant differences in lesion morphology, non-mass-like enhancement pattern, and apparent diffusion coefficient value (P > 0.05). The HER-2 positive group showed clumped enhancement (65.5%), type Ⅱ (48.1%) andtype Ⅲ (29.6%) time-intensity curves, and microvascular sign (89.7%). The HER-2 negative group showed clusteredring enhancement (50.0%), type Ⅱ (45.8%) and type I (54.2%) time-intensity curves, and microvascular sign (54.2%). A combination of clumped enhancement, microvascular sign, and type Ⅲ time-intensity curve showed 100% specificity and 100% positive predictive value for the diagnosis of HER-2 positive DCIS. Conclusion Clumped enhancement, microvascular sign, and type Ⅱ or Ⅲ time-intensity curve on MRI can largely reflect the expression of HER-2 in DCIS. The three can be used in combination to improve the diagnostic efficiency of HER-2 positive DCIS.

2.
Rev. biol. trop ; 62(1): 47-58, ene.-mar. 2014. ilus, mapas, tab
Article Dans Anglais | LILACS | ID: lil-715413

Résumé

Additive partitioning of species diversity is a promising approach for analyzing patterns of diversity in mollusk communities, especially their spatial distribution. Our aims were to assess the distribution of mollusk communities in Southern Brazilian streams, and to evaluate the partitioning of community diversity at different spatial scales. The study was carried out in the lower course of the Toropi River, one of the main tributaries of the Ibicuí River Basin, in Southern Brazil. Four microbasins were considered: Sertão da Mata, Ribeirão, Tororaipi and Chiniquá, and sampling were undertaken in autumn, April and May 2009. Six sites were sampled in each stream: two in 1st-order segments, two in 2nd-order segments, and two in 3rd-order segments. All species found and the community as a whole, exhibited a clumped distribution. However, the variance-to-mean ratios for the Drepanotrema kermatoides and Heleobia bertoniana were higher than those of other species, suggesting a higher degree of aggregation. The additive partitioning of the species richness showed that the observed richness at smallest scale (α=within streams) represented 20.7%, and among-streams (β1) represented 10.5% of the total richness. The richness and Shannon diversity index observed at the alpha scale, were higher than those observed at the first level of beta diversity scale (β1=among-streams). The interaction between passive dispersal, tolerance to changes in some environmental variables, abiotic factors, and clumped distribution might have determined the spatial distribution of the communities studied. The greatest variation at the larger scales of analysis, involving among-orders and among-microbasins (β2 and β3, respectively) components, was expected, considering that the increase in distance leads to greater differences in richness (higher beta diversity). In conclusion, our results showed that the clumped distribution influenced the partition of the diversity of the mollusk communities in the streams studied. Dispersal methods and tolerance to variations in abiotic factors also have important roles in determining high alpha diversity. The partitioning of diversity showed that to preserve limnetic mollusks, it is important to preserve local areas, i.e., streams. Accordingly, conservation of streams on a local scale will contribute to conservation of the entire basin and maintenance of regional diversity (gamma).


La partición aditiva de la diversidad de especies es un enfoque prometedor para el análisis de los patrones de diversidad en las comunidades de moluscos, especialmente su distribución espacial. Nuestros objetivos fueron evaluar la distribución de las comunidades de moluscos en los arroyos en el Sur de Brasil, y evaluar la partición de diversidad de la comunidad en diferentes escalas espaciales. El muestreo se llevó a cabo en cuatro cuencas del curso inferior del río Toropi, Brasil. Todas las especies encontradas, y también la comunidad en su conjunto mostraron una distribución agregada. La partición aditiva de la riqueza de especies mostró que la riqueza observada en menor escala (α=dentro de los arroyos) representó el 20.7%, y entre los arroyos (β1) representó el 10.5% de la riqueza total. La riqueza y diversidad de Shannon observadas en escala alfa (α=dentro de los arroyos) fueron mayores que las observadas en el primer nivel de escala de la diversidad beta (β1=entre los arroyos). La mayor variación en las grandes escalas de análisis, con la participación de los componentes entre- órdenes y entre-microcuencas (β2 y β3, respectivamente) fue la esperada, ya que el aumento de la distancia conduce a mayores diferencias de riqueza (mayor diversidad beta). En conclusión, nuestros resultados muestran que la dispersión agregada tuvo influencia en la partición de la diversidad de las comunidades de moluscos en los arroyos estudiados. Los métodos de dispersión y tolerancia a las variaciones de los factores abióticos también juegan un papel importante para determinar la diversidad alfa. Así, la conservación de los arroyos a nivel local contribuirá a la conservación de la cuenca y al mantenimiento de la diversidad regional (gamma).


Sujets)
Animaux , Biodiversité , Mollusca/classification , Brésil , Densité de population , Dynamique des populations , Rivières
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